高能、长循环寿命和高充放电速率的阴极材料是限制发展静态稳定电能存储和动力电源用先进锂电池的关键材料问题。基于脱嵌锂过程的层状锂过渡金属氧化物、过渡金属磷酸锂和富锂氧化物的阴极材料的容量发展遇到了瓶颈,因此探索基于新电...高能、长循环寿命和高充放电速率的阴极材料是限制发展静态稳定电能存储和动力电源用先进锂电池的关键材料问题。基于脱嵌锂过程的层状锂过渡金属氧化物、过渡金属磷酸锂和富锂氧化物的阴极材料的容量发展遇到了瓶颈,因此探索基于新电化学过程的新型高容量阴极材料的研究非常重要。基于硫(S)和Li2S的阴极材料具有高的理论容量(1673mA h g-1和1166mA h g-1),成为发展高容量和高能锂离子电池阴极材料研究的重点。综述了解决硫阴极材料面临的电子和锂离子传导能力差、充放电过程中可溶性硫的溶解及体积变化等关键科学问题的新思路和新方法,为发展新型硫阴极材料提供参考和启发。展开更多
Human body communication is proposed as a promising body proximal comanunication tech- nology for body sensor networks. To achieve low power and slmll volume ill the sensor nodes, a Ra-dio Frequency (RF) application...Human body communication is proposed as a promising body proximal comanunication tech- nology for body sensor networks. To achieve low power and slmll volume ill the sensor nodes, a Ra-dio Frequency (RF) application-specific integrated circuit transceiver tbr Human Body Commnunication (HBC) is presented and the characteristics of HBC are investigated. A high data rate On-Off Keying (OOK)/Frequency-Shift Keying (FSK) modulation protocol and an OOK/FSK delrodulator circuit are introduced in this paper, with a data-rate-to-carrier-frequency ratio up to 70%. A low noise amplifier is proposed to handle the dynamic range problem and improve the sensitivity of the receiver path. In addi-tion, a low power autonmatic-gain-control system is realized using a novel architecture, thereby render-ing the peak detector circuit and loop filter unneces-sary. Finally, the complete chip is fabricated. Simula-tion results suggest receiver sensitivity to be-75 dBm. The transceiver shows an overall power con-smxption of 32 mW when data rate is 5 Mbps, de-livering a P1dB output power of - 30 dBm.展开更多
文摘高能、长循环寿命和高充放电速率的阴极材料是限制发展静态稳定电能存储和动力电源用先进锂电池的关键材料问题。基于脱嵌锂过程的层状锂过渡金属氧化物、过渡金属磷酸锂和富锂氧化物的阴极材料的容量发展遇到了瓶颈,因此探索基于新电化学过程的新型高容量阴极材料的研究非常重要。基于硫(S)和Li2S的阴极材料具有高的理论容量(1673mA h g-1和1166mA h g-1),成为发展高容量和高能锂离子电池阴极材料研究的重点。综述了解决硫阴极材料面临的电子和锂离子传导能力差、充放电过程中可溶性硫的溶解及体积变化等关键科学问题的新思路和新方法,为发展新型硫阴极材料提供参考和启发。
基金This study was supported partially by the Projects of National Natural Science Foundation of China under Crants No. 60932001, No.61072031 the National 863 Program of China un-der Crant No. 2012AA02A604+3 种基金 the National 973 Program of China under Cwant No. 2010CB732606 the Next Generation Communication Technology Major Project of National S&T un-der Crant No. 2013ZX03005013 the "One-hundred Talent" and the "Low-cost Healthcare" Programs of Chinese Academy of Sciences and the Guangdong Innovation Research Team Funds for Low-cost Healthcare and Irrage-Guided Therapy.
文摘Human body communication is proposed as a promising body proximal comanunication tech- nology for body sensor networks. To achieve low power and slmll volume ill the sensor nodes, a Ra-dio Frequency (RF) application-specific integrated circuit transceiver tbr Human Body Commnunication (HBC) is presented and the characteristics of HBC are investigated. A high data rate On-Off Keying (OOK)/Frequency-Shift Keying (FSK) modulation protocol and an OOK/FSK delrodulator circuit are introduced in this paper, with a data-rate-to-carrier-frequency ratio up to 70%. A low noise amplifier is proposed to handle the dynamic range problem and improve the sensitivity of the receiver path. In addi-tion, a low power autonmatic-gain-control system is realized using a novel architecture, thereby render-ing the peak detector circuit and loop filter unneces-sary. Finally, the complete chip is fabricated. Simula-tion results suggest receiver sensitivity to be-75 dBm. The transceiver shows an overall power con-smxption of 32 mW when data rate is 5 Mbps, de-livering a P1dB output power of - 30 dBm.