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排序方式: 共有506条查询结果,搜索用时 15 毫秒
501.
Shinichi Komaba Wataru Murata Toru Ishikawa Naoaki Yabuuchi Tomoaki Ozeki Tetsuri Nakayama Atsushi Ogata Kazuma Gotoh Kazuya Fujiwara 《Advanced functional materials》2011,21(20):3859-3867
Recently, lithium‐ion batteries have been attracting more interest for use in automotive applications. Lithium resources are confirmed to be unevenly distributed in South America, and the cost of the lithium raw materials has roughly doubled from the first practical application in 1991 to the present and is increasing due to global demand for lithium‐ion accumulators. Since the electrochemical equivalent and standard potential of sodium are the most advantageous after lithium, sodium based energy storage is of great interest to realize lithium‐free high energy and high voltage batteries. However, to the best of our knowledge, there have been no successful reports on electrochemical sodium insertion materials for battery applications; the major challenge is the negative electrode and its passivation. In this study, we achieve high capacity and excellent reversibility sodium‐insertion performance of hard‐carbon and layered NaNi0.5Mn0.5O2 electrodes in propylene carbonate electrolyte solutions. The structural change and passivation for hard‐carbon are investigated to study the reversible sodium insertion. The 3‐volt secondary Na‐ion battery possessing environmental and cost friendliness, Na+‐shuttlecock hard‐carbon/NaNi0.5Mn0.5O2 cell, demonstrates steady cycling performance as next generation secondary batteries and an alternative to Li‐ion batteries. 相似文献
502.
Komaba S Ishikawa T Yabuuchi N Murata W Ito A Ohsawa Y 《ACS applied materials & interfaces》2011,3(11):4165-4168
Fluoroethylene carbonate is an efficient electrolyte additive to improve the reversibility of electrochemical sodium insertion for hard-carbon and NaNi(1/2)Mn(1/2)O(2) electrodes in aprotic Na cells. The additive is also capable of the electrochemical deposition/dissolution of metallic Na with higher reversibility because of improved passivation and suppression of side reactions between Na metal and propylene carbonate solution containing Na salts. 相似文献
503.
504.
Yasuyoshi Yokokohji Yoshihiro Kawai Mizuho Shibata Yasumichi Aiyama Shinya Kotosaka Wataru Uemura 《Advanced Robotics》2019,33(17):876-899
ABSTRACTThe World Robot Summit (WRS) is a robotic ‘challenge and exposition’ organized by the Japanese government to accelerate social implementation, research and development of robots working in realistic daily life, society, and industrial fields. In this paper, we introduce a robot competition of the Industrial Robotics Category of the WRS, called ‘Assembly Challenge’, which is organized by the WRS Industrial Robotics Competition Committee in order to promote the development of the next-generation production systems that can respond to new production demands in agile and lean manners. Prior to the main competition in 2020, a pre-competition was held in 2018 with 16 participating teams from around the world. In this paper, we introduce the contents and results of this pre-competition, analyze the results, and give a perspective for the 2020 main competition. 相似文献
505.
Horie Junpei Noguchi Wataru Iizuka Hiroyuki Yamamoto Masahito 《Artificial Life and Robotics》2023,28(1):148-157
Artificial Life and Robotics - Multimodal learning of motion and text tries to find the correspondence between skeletal time-series data acquired by motion capture and the text that describes the... 相似文献
506.
Wataru Kuriyama Yasunori Ino Osamu Ogata Noboru Sayo Takao Saito 《Advanced Synthesis \u0026amp; Catalysis》2010,352(1):92-96
A ruthenium complex was found to catalyze the hydrogen reduction of esters under mild and neutral conditions. A variety of optically active esters can be reduced to the corresponding alcohols in excellent yield without loss of their optical purity or causing undesirable side reactions. Hydrogen reduction needs such simple operations – reaction, concentration, and purification – that the violent quench step and extraction step, which accompany conventional sodium borohydride or lithium aluminum hydride reduction, can be omitted. 相似文献