Using the extensively studied V_(2)O_(3) as a prototype system, we investigate the role of percolation in metal-insulator transition(MIT). We apply scanning microwave impedance microscopy to directly determine the met...Using the extensively studied V_(2)O_(3) as a prototype system, we investigate the role of percolation in metal-insulator transition(MIT). We apply scanning microwave impedance microscopy to directly determine the metallic phase fraction p and relate it to the macroscopic conductance G, which shows a sudden jump when p reaches the percolation threshold. Interestingly, the conductance G exhibits a hysteretic behavior against p, suggesting two different percolating processes upon cooling and warming. Based on our image analysis and model simulation, we ascribe such hysteretic behavior to different domain nucleation and growth processes between cooling and warming, which is likely caused by the decoupled structural and electronic transitions in V_(2)O_(3) during MIT. Our work provides a microscopic view of how the interplay of structural and electronic degrees of freedom affects MIT in strongly correlated systems.展开更多
Cassava,a tropical food,feed and biofuel crop,has great capacity for biomass accumulation and an extraordinary efficiency in water use and mineral nutrition,which makes it highly suitable as a model plant for tropical...Cassava,a tropical food,feed and biofuel crop,has great capacity for biomass accumulation and an extraordinary efficiency in water use and mineral nutrition,which makes it highly suitable as a model plant for tropical crops.However,the understanding of the metabolism and genomics of this important crop is limited.The recent breakthroughs in the genomics of cassava,including whole-genome sequencing and transcriptome analysis,as well as advances in the biology of photosynthesis,starch biosynthesis,adaptation to drought and high temperature,and resistance to virus and bacterial diseases,are reviewed here.Many of the new developments have come from comparative analyses between a wild ancestor and existing cultivars.Finally,the current challenges and future potential of cassava as a model plant are discussed.展开更多
基金Fudan University was supported by the National Natural Science Foundation of China (Grant Nos. 12074080, 11804052, 11827805,11725521, and 12035004)the National Postdoctoral Program for Innovative Talents (Grant No. BX20180079)+5 种基金the Shanghai Science and Technology Committee Rising-Star Program (Grant No. 19QA1401000)the Science and Technology Commission of Shanghai Municipality (Grant No.20JC1414700)the Major Project (Grant No. 2019SHZDZX01)the Ministry of Science and Technology of China (Grant Nos. 2017YFA03030002021YFA1400100)(synthesis, structural characterization and global transport of V2O3) at University of California San Diego was supported by the US Air Force Office of Scientific Research (Grant No.FA9550-20-1-0242)。
文摘Using the extensively studied V_(2)O_(3) as a prototype system, we investigate the role of percolation in metal-insulator transition(MIT). We apply scanning microwave impedance microscopy to directly determine the metallic phase fraction p and relate it to the macroscopic conductance G, which shows a sudden jump when p reaches the percolation threshold. Interestingly, the conductance G exhibits a hysteretic behavior against p, suggesting two different percolating processes upon cooling and warming. Based on our image analysis and model simulation, we ascribe such hysteretic behavior to different domain nucleation and growth processes between cooling and warming, which is likely caused by the decoupled structural and electronic transitions in V_(2)O_(3) during MIT. Our work provides a microscopic view of how the interplay of structural and electronic degrees of freedom affects MIT in strongly correlated systems.
基金This work was funded by the National Basic Research Program of China(2010CB126601)the National Natural Science Foundation of China(31261140363 and 31171230)+2 种基金the China Agriculture Research System(CARS-12)the National International Science and Technology Cooperation Plan(2011DFB31690)the National High Technology Research and Development Program of China(2012AA101204-2).
文摘Cassava,a tropical food,feed and biofuel crop,has great capacity for biomass accumulation and an extraordinary efficiency in water use and mineral nutrition,which makes it highly suitable as a model plant for tropical crops.However,the understanding of the metabolism and genomics of this important crop is limited.The recent breakthroughs in the genomics of cassava,including whole-genome sequencing and transcriptome analysis,as well as advances in the biology of photosynthesis,starch biosynthesis,adaptation to drought and high temperature,and resistance to virus and bacterial diseases,are reviewed here.Many of the new developments have come from comparative analyses between a wild ancestor and existing cultivars.Finally,the current challenges and future potential of cassava as a model plant are discussed.
