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921.
922.
923.
Jianwen Liang Xiaona Li Yang Zhao Lyudmila V. Goncharova Weihan Li Keegan R. Adair Mohammad Norouzi Banis Yongfeng Hu Tsun‐Kong Sham Huan Huang Li Zhang Shangqian Zhao Shigang Lu Ruying Li Xueliang Sun 《Liver Transplantation》2019,9(38)
Li metal is a promising anode material for all‐solid‐state batteries, owing to its high specific capacity and low electrochemical potential. However, direct contact of Li metal with most solid‐state electrolytes induces severe side reactions that can lead to dendrite formation and short circuits. Moreover, Li metal is unstable when exposed to air, leading to stringent processing requirements. Herein, it is reported that the Li3PS4/Li interface in all‐solid‐state batteries can be stabilized by an air‐stable LixSiSy protection layer that is formed in situ on the surface of Li metal through a solution‐based method. Highly stable Li cycling for over 2000 h in symmetrical cells and a lifetime of over 100 cycles can be achieved for an all‐solid‐state LiCoO2/Li3PS4/Li cell. Synchrotron‐based high energy X‐ray photoelectron spectroscopy in‐depth analysis demonstrates the distribution of different components within the protection layer. The in situ formation of an electronically insulating LixSiSy protection layer with highly ionic conductivity provides an effective way to prevent Li dendrite formation in high‐energy all‐solid‐state Li metal batteries. 相似文献
924.
Yin Hu Wei Chen Tianyu Lei Bin Zhou Yu Jiao Yichao Yan Xinchuan Du Jianwen Huang Chunyang Wu Xuepeng Wang Yang Wang Bo Chen Jun Xu Chao Wang Jie Xiong 《Liver Transplantation》2019,9(7)
Significant progress has achieved for developing lithium–sulfur (Li–S) batteries with high specific capacities and excellent cyclic stability. However, some critical issues emerge when attempts are made to raise the areal sulfur loading and increase the operation current density to meet the standards for various industrial applications. In this work, polyethylenimine‐functionalized carbon dots (PEI‐CDots) are designed and prepared for enhancing performance of the Li–S batteries with high sulfur loadings and operation under high current density situations. Strong chemical binding effects towards polysulfides and fast ion transport property are achieved in the PEI‐CDots‐modified cathodes. At a high current density of 8 mA cm?2, the PEI‐CDots‐modified Li–S battery delivers a reversible areal capacity of 3.3 mAh cm?2 with only 0.07% capacity decay per cycle over 400 cycles at 6.6 mg sulfur loading. Detailed analysis, involving electrochemical impedance spectroscopy, cyclic voltammetry, and density functional theory calculations, is done for the elucidation of the underlying enhancement mechanism by the PEI‐CDots. The strongly localized sulfur species and the promoted Li+ ion conductivity at the cathode–electrolyte interface are revealed to enable high‐performance Li–S batteries with high sulfur loading and large operational current. 相似文献
925.
Ming‐Jian Zhang Xiaobing Hu Maofan Li Yandong Duan Luyi Yang Chong Yin Mingyuan Ge Xianghui Xiao Wah‐Keat Lee Jun Young Peter Ko Khalil Amine Zonghai Chen Yimei Zhu Eric Dooryhee Jianming Bai Feng Pan Feng Wang 《Liver Transplantation》2019,9(43)
Transition metal layered oxides have been the dominant cathodes in lithium‐ion batteries, and among them, high‐Ni ones (LiNixMnyCozO2; x ≥ 0.7) with greatly boosted capacity and reduced cost are of particular interest for large‐scale applications. The high Ni loading, on the other hand, raises the critical issues of surface instability and poor rate performance. The rational design of synthesis leading to layered LiNi0.7Mn0.15Co0.15O2 with greatly enhanced rate capability is demonstrated, by implementing a quenching process alternative to the general slow cooling. In situ synchrotron X‐ray diffraction, coupled with surface analysis, is applied to studies of the synthesis process, revealing cooling‐induced surface reconstruction involving Li2CO3 accumulation, formation of a Li‐deficient layer and Ni reduction at the particle surface. The reconstruction process occurs predominantly at high temperatures (above 350 °C) and is highly cooling‐rate dependent, implying that surface reconstruction can be suppressed through synthetic control, i.e., quenching to improve the surface stability and rate performance of the synthesized materials. These findings may provide guidance to rational synthesis of high‐Ni cathode materials. 相似文献
926.
Yanting Hu Ping Zhao Yuqing Huang Liwei Zhu Guangyan Ni Xiuhua Zhao Zhihong Huang 《Journal of Plant Ecology》2019,12(6):982
Aims
Land cover changes can disrupt water balance and alter the partitioning of precipitation into surface runoff, evapotranspiration and groundwater recharge. The widely plantedEucalyptustrees in south-western China have the potential to bring about hydrologic impacts. Our research aims to elucidate the hydrologic balance characteristics of the introduced exoticEucalyptus grandis×Eucalyptus urophyllaplantation and to assess whether its high productivity results from high water use efficiency (WUE) or large water consumption. 相似文献
927.
Guangyi Fan Yaolei Zhang Xiaochuan Liu Jiahao Wang Zeguo Sun Shuai Sun He Zhang Jianwei Chen Meiqi Lv Kai Han Xiaoxuan Tan Jie Hu Rui Guan Yuanyuan Fu Shanshan Liu Xi Chen Qiwu Xu Yating Qin Longqi Liu Jie Bai Ou Wang Jingbo Tang Haorong Lu Zhouchun Shang Bo Wang Guohai Hu Xia Zhao Yan Zou Ao Chen Meihua Gong Wenwei Zhang Simon M.‐Y. Lee Songhai Li Junnian Liu Zhen Li Yishan Lu Jamal S. M. Sabir Mumdooh J. Sabir Muhummadh Khan Nahid H. Hajrah Ye Yin Karsten Kristiansen Huanming Yang Jian Wang Xun Xu Xin Liu 《Molecular ecology resources》2019,19(4):944-956
Marine mammals are important models for studying convergent evolution and aquatic adaption, and thus reference genomes of marine mammals can provide evolutionary insights. Here, we present the first chromosome‐level marine mammal genome assembly based on the data generated by the BGISEQ‐500 platform, for a stranded female sperm whale (Physeter macrocephalus). Using this reference genome, we performed chromosome evolution analysis of the sperm whale, including constructing ancestral chromosomes, identifying chromosome rearrangement events and comparing with cattle chromosomes, which provides a resource for exploring marine mammal adaptation and speciation. We detected a high proportion of long interspersed nuclear elements and expanded gene families, and contraction of major histocompatibility complex region genes which were specific to sperm whale. Using comparisons with sheep and cattle, we analysed positively selected genes to identify gene pathways that may be related to adaptation to the marine environment. Further, we identified possible convergent evolution in aquatic mammals by testing for positively selected genes across three orders of marine mammals. In addition, we used publicly available resequencing data to confirm a rapid decline in global population size in the Pliocene to Pleistocene transition. This study sheds light on the chromosome evolution and genetic mechanisms underpinning sperm whale adaptations, providing valuable resources for future comparative genomics. 相似文献
928.
929.