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991.
Development of aqueous rechargeable zinc ion battery is an important direction towards grid energy storage sought in various applications.At present,the efficient utilization of aqueous rechargeable zinc ion batteries has been seriously affected due to the defects nature of the cathode materials,such as poor capacity,limited rate performance,and limited cycle stability.Therefore,the search for high-performance cathode materials is a main challenge in this field.Herein,we in-situ prepared graphdiyne-wrapped K0.25·MnO2(K0.25·MnO2@GDY)hybrid nanowall arrays as the cathode of aqueous rechargeable zinc ion battery.The hybridnanowall arrays have obviously alleviated the pulverization and sluggish kinetic process of MnO2 cathode materials and shown high specific capacity(520 mA·h/g at a current density of 55 mA/g),which is near-full two-electron capacity.The high specific capacity was resulted from more than one Zn2+(de)intercalation process occurring per formula unit,in which we observed a structural evolution that partially stemmed from ion exchange between the intercalated K+and Zn2+ions during the discharge process.The present investigation not only provides a new material for the aqueous rechargeable Zn ion batteries,also contributes a novel route for the development of next generation aqueous rechargeable Zn ion batteries with high capacity. 相似文献
992.
Zinc-ion hybrid super-capacitors are regarded as promising safe energy storage systems. However, the relatively low volumetric energy density has become the main bottlenecks in practical applications of portable electronic devices. In this work, the zinc-ion hybrid super-capacitor with high volumetric energy density and superb cycle stability had been constructed which employing the high-density three-dimensional graphene hydrogel as cathode and Zn foil used as anode in 1 mol/L ZnSO4 electrolyte. Benefiting from the abundant ion transport paths and the abundant active sites for graphene hydrogel with high density and porous structure, the zinc-ion hybrid super-capacitor exhibited an extremely high volumetric energy density of 118.42 Wh/L and a superb power density of 24.00 kW/L, as well as an excellent long cycle life (80% retention after 30,000 cycles at 10 A/g), which was superior to the volumetric energy density of the reported zinc-ion hybrid super-capacitors. This device, based on the fast ion adsorption/desorption on the capacitor-type graphene cathode and reversible Zn2+ plating/stripping on the battery-type Zn anode, which will inspire the development of zinc-ion hybrid super-capacitor in miniaturized devices. 相似文献
993.
BaTiO3 dielectric capacitors, one of the important energy storage devices, play critical roles in storing electricity from renewable energies of water, wind, solar, etc. The synthesis of BaTiO3 ceramics with weak temperature dependence and a high dielectric constant at room temperature (εRT′) is an urgent problem to meet the miniaturization and large capacity of dielectric capacitors. Doping rare earth elements into BaTiO3 can solve this problem, but it is still challenging. In this work, we adopt a synergistic strategy of increasing εRT′ and improving the temperature stability by codoping Gd3+ and Ho3+, respectively, to address this challenge. By carefully adjusting the synthesis conditions in the solid-state reaction, codoping 7% Gd3+ and 7% Ho3+ in BaTiO3 (BGTH7) ceramics were synthesized. The temperature-dependent dielectric constant reveals that the obtained optimal BGTH7 ceramic satisfies the X7U specification and displays a stable ε′ in the temperature range of −55~125 °C. The optimal BGTH7 ceramic after sintering at 1400 °C for 6 h exhibits a high dielectric constant of 5475 and low dielectric loss (tan δ) of 0.0176, hitherto exhibiting the best performance in X7U ceramics. The findings in this work are conducive to the miniaturization and stabilization of dielectric energy storage devices. 相似文献
994.
995.
本文依据有壳梯黑(35/65)装药部件的贮存检测数据,应用统计回归分析,拟合出该装药的密度下降规律,以及年均体膨胀率,发现该装药在贮存过程中的体积长大确是一个不容忽视的问题,特别是当具有坚固外壳时,这种体胀率会转化成内应力,所以必须给予充分的重视。 相似文献
996.
对PEOS功率倍增装置进行了物理设计与模拟计算并进行了脉冲等离子体枪实验。给出装置参数的选择方法,包括电路参数与PEOS参数的选择。为得到要求的功率倍增和能量传输效率,分析指出注入等离子体密度n_p与速度v_d的乘积要大而n_p相对要小,v_d要大;而且为断路快、阴极半径r要适当小;模拟计算结果证实了这一分析。对装置关键部件脉冲等离子体枪进行设计、研制和实验,在距枪60cm处测得碳离子速度v_d~5×10~(?)cm/s,离子密度n_p~4×10(?)/cm。 相似文献
997.
氧钒酞菁在激光光盘系统中的应用研究 总被引:3,自引:0,他引:3
氧钒酞菁在激光光盘系统中的应用研究董长征,沈永嘉,任绳武(华东理工大学精细化工研究所上海200237)袁海俊(中国科学院上海光学精密机械研究所上海201800)关键词:信息储存,激光光盘,功能染料,氧钒酞菁自1972年Philips公司推出激光光盘(... 相似文献
998.
高密度数字视盘(HD-DVD)是一种新型蓝光存储技术,可以满足数字高清视频节目的播放要求.介绍了用于HD-DVD驱动器中的刀口法调焦方案,基于菲涅耳公式和标量衍射理论,推导了刀口法调焦的HD-DVD驱动器中聚焦误差信号与离焦量之间关系的计算模型.应用该计算模型,分析了不同离焦量时探测器上光强分布情况.计算得到的聚焦误差信号与离焦量之间的关系曲线与实验测得的“S型”曲线相一致,证明了计算模型的正确性.进一步分析了正焦点时由于记录符调制而引起的聚焦误差的干扰信号,计算结果表明这种干扰的强度小于4.5%.分析表
关键词:
光存储
刀口法
聚焦误差
标量衍射 相似文献
999.
MlNi4Al和MlNi4Mn贮氢电极性能的研究*赵东江马松艳(绥化师专化学系绥化152061)关键词贮氢电极循环寿命自放电中图分类号O646.54镍/氢化物(Ni/MH)二次电池以其洁净、安全、高容量、大功率及长寿命等特点受到极大关注。贮氢电极材料... 相似文献
1000.
In this work, convex diffractive microlenses are designed for fabrication in GaN-based material with a gray-level mask. The aspect ratios of the surface relief of plano-convex and double-convex microlenses for different numerical apertures are compared to reduce the fabrication difficulty. The results show that for the numerical aperture less than 0.6, the aspect ratio of the double-convex diffractive microlenses is around half of the plano-convex diffractive microlenses. For the numerical aperture higher than 0.6, the aspect ratio of the plano-convex diffractive microlenses is similar to the double-convex diffractive microlenses. The error of the surface relief of the microlens occurring during the fabrication process is also discussed. 相似文献