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131.
132.
张曼曼;努尔买买提·莫明;王虹;布佐日古丽·喀迪尔;姜彦成 《植物研究》2013,33(1):7-17
利用光学显微镜和扫描电子显微镜,观察了新疆委陵菜属(Potentilla L.)锥状花柱组(Sect.Conostylae(Wolf)Yü et Li)15种委陵菜植物叶表皮的微形态特征。对其叶表皮毛的类型、表皮细胞的形状及大小、气孔器的分布、气孔器类型、气孔形状、气孔大小、气孔密度、气孔指数、气孔外拱盖形态及其纹饰等指标进行分析:有几种植物叶的上表皮无气孔,而下表皮均有气孔器的分布,形状为长椭圆形、椭圆形、宽椭圆形和近圆形;气孔器的类型多为短平列四细胞型、无规则四细胞型、无规则型、围绕型和辐射型;表皮毛的类型为针状毛、带状柔毛和腺毛;表皮细胞分为不规则形和多边形;表皮毛特征、叶片表皮细胞的形状、垂周壁式样、气孔器的形状类型、气孔密度指数及蜡质纹饰等存在差异,可作为亚属间及种间分类的依据。 相似文献
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Wenbin Fu Enbo Zhao Ruiying Ma Zifei Sun Yang Yang Marta Sevilla Antonio B. Fuertes Alexandre Magasinski Gleb Yushin 《Liver Transplantation》2020,10(2)
Li‐ion hybrid supercapacitors (Li‐HSCs) hold great promise in future electrical energy storage due to their relatively high power and energy density. However, a major challenge lies in the slow kinetics of Li‐ion intercalation/extraction within metal‐oxide electrodes. Here, it is shown that ultrafast charge storage is realized by confining anatase TiO2 nanoparticles in carbon nanopores to enable a high‐rate anode for Li‐HSCs. The porous carbon with interconnected pore walls and open channels not only works as a conductive host to protect TiO2 from structural degradation but also provides fast pathways for ion/electron transport. As a result, the assembled cells exhibit remarkable rate capabilities with a specific capacity of ≈140 mAh g?1 at a slow charge and ≈60 mAh g?1 at a 3.5 s fast charge. While the charge/discharge process can be completed as fast as that of state‐of‐the‐art electrical double‐layer capacitors (EDLCs), the produced nanocomposites show three to seven times higher volumetric capacitance than activated carbons used in commercial EDLCs with acetonitrile‐based electrolytes. Equally important for some applications in cold climates or the space, the Li‐HSCs can operate at subzero temperatures as low as ?40 °C, which is likely only limited by thermal properties of the acetonitrile (melting point of ?45 °C). 相似文献
137.
Yipeng Sun Maedeh Amirmaleki Yang Zhao Changtai Zhao Jianneng Liang Changhong Wang Keegan R. Adair Junjie Li Teng Cui Guorui Wang Ruying Li Tobin Filleter Mei Cai Tsun‐Kong Sham Xueliang Sun 《Liver Transplantation》2020,10(28)
Lithium metal is regarded as the “Holy Grail” of anode materials due to its low electrochemical potential and high theoretical capacity. Unfortunately, its unstable solid electrolyte interphase (SEI) leads to low Coulombic efficiency (CE) and serious safety issues. Herein, a hybrid nanoscale polymeric protective film with tunable composition and improved stiffness is developed by incorporating aluminum crosslinkers into the polymer chains. The Li plating/stripping process is regulated through the protective coating and the dendrite growth is effectively suppressed. Promisingly, the protected Li can deliver stable performance for more than 350 h with a cycling capacity of 2 mAh cm?2 without a notable increase in overpotential. Moreover, a stable charge/discharge cycling in Li–O2 batteries with the protected Li can be maintained for more than 600 h. This work provides guidance on the rational design of electrode interfaces and opens up new opportunities for the fabrication of next‐generation energy storage systems. 相似文献
138.
Han Deng Zhi Chang Feilong Qiu Yu Qiao Huijun Yang Ping He Haoshen Zhou 《Liver Transplantation》2020,10(12)
Safe rechargeable batteries of improved energy density and high power performance are urgently needed for the development of large electric devices. Herein, an Li‐based organic liquid anode is proposed, and an organic oxygen battery with a metal organic framework membrane separator is realized, which is able to conduct Li ions and separate other large species in the system. Equipped with the dual redox mediator strategy, the organic oxygen battery exhibits superior rate performance with long cycling life and low overpotential. A “solid electrolyte interface”‐like layer is observed between the organic liquid anode and the ion conducting separator. This work not only introduces a new type of anode for Li‐based batteries, but also provides fundamental insights for the better application of biphenyl‐based liquid anodes. 相似文献
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Microcalorimetry was employed to investigate the action of Li(I) to aquatic ecosystem from the point view of bioenergetics. Tetrahymena thermophila BF5 was chosen as the model organism. The power-time curves of T. thermophila BF5 growth metabolism in the absence and presence of Li(I) were obtained. The corresponding thermokinetic parameters were derived. The generation time was calculated as 592.3 min, which was consistent with the biomass values. Low concentration of Li(I) (1-20 mmol l-1) stimulated the growth of T. thermophila BF5, whereas the inhibition effect was observed in high concentration (30-100 mmol l-1). The value of IC50 was 52.8 mmol l-1. In the concentration range of 30-100 mmol l-1, the growth rate constants (k) and the maximum heat out power (P max) decrease with the concentration of Li(I), whereas the heat output (Q) increases slightly compared to the control. Other than the classic mechanism of inositol-phosphate cycle, the involvement of mitochondria mechanism was discussed and suggested. 相似文献