The battery management system is employed to monitor the external temperature of the lithium-ion battery in order to detect any potential overheating.However,this outside–in detection method often suffers from a lag ...The battery management system is employed to monitor the external temperature of the lithium-ion battery in order to detect any potential overheating.However,this outside–in detection method often suffers from a lag and is therefore unable to accurately predict the battery’s real-time state.Herein,an inside–out frequency response approach is used to accurately monitor the battery’s state at various temperatures in real-time and correlate it with the solid electrolyte interphase(SEI)evolution of the graphite electrode.The SEI evolution at temperatures of−15,25,60,and 90℃exhibits certain regular characteristics with temperature change.At a temperature of−15℃,the Li^(+)-solvent interaction of lithium-ion slowed down,resulting in a significant reduction in performance.At 25℃,a LiF-rich inorganic SEI was identified as forming,which facilitated lithium-ion transportation.However,high temperatures would induce decomposition of lithium hexafluorophosphate(LiPF_(6))and lithium-ion electrolyte.At the extreme temperature of 90℃,the SEI would be organic-rich,and Li_(x)P_(y)F_(z),a decomposition product of lithium salts,was further oxidized to Li_(x)PO_(y)F_(z),which led to a surge in the charge-transfer resistance at SEI(R_(sei))and a reduction in Coulombic efficiency(CE).This changing relationship can be recorded in real time from the inside out by electrochemical impedance spectroscopy(EIS)testing.This provides a new theoretical basis for the structural evolution of lithium-ion batteries and the regular characterization of EIS.展开更多
This paper discusses ancestral hall architecture within the context of the Cantonese folk lineage in the Pearl River Delta.Using a typological research approach and chronological analysis,various factors that have inf...This paper discusses ancestral hall architecture within the context of the Cantonese folk lineage in the Pearl River Delta.Using a typological research approach and chronological analysis,various factors that have influenced the evolution of ancestral hall architecture are analyzed.The study specifically investigates the features of ancestral halls during the Ming and Qing dynasties.Three periods of ancient China are analyzed:The transition from Ming to Qing,the mid-Qing dynasty,and the late Qing dynasty.The variables of each period and how they influence the evolution of architectural typological features are identified.Based on our analysis,architectural features are related to economic and social factors,materials available,and craftsmanship of the construction workers.展开更多
The Yellow River has a vast catchment area and historically it is the mother river of the Chinese nation. Now it serves as one of the main theatres for the on-going national campaign to develop China's western... The Yellow River has a vast catchment area and historically it is the mother river of the Chinese nation. Now it serves as one of the main theatres for the on-going national campaign to develop China's western hinterland.……展开更多
Purpose:This paper aims to address the limitations in existing research on the evolution of knowledge flow networks by proposing a meso-level institutional field knowledge flow network evolution model(IKM).The purpose...Purpose:This paper aims to address the limitations in existing research on the evolution of knowledge flow networks by proposing a meso-level institutional field knowledge flow network evolution model(IKM).The purpose is to simulate the construction process of a knowledge flow network using knowledge organizations as units and to investigate its effectiveness in replicating institutional field knowledge flow networks.Design/Methodology/Approach:The IKM model enhances the preferential attachment and growth observed in scale-free BA networks,while incorporating three adjustment parameters to simulate the selection of connection targets and the types of nodes involved in the network evolution process Using the PageRank algorithm to calculate the significance of nodes within the knowledge flow network.To compare its performance,the BA and DMS models are also employed for simulating the network.Pearson coefficient analysis is conducted on the simulated networks generated by the IKM,BA and DMS models,as well as on the actual network.Findings:The research findings demonstrate that the IKM model outperforms the BA and DMS models in replicating the institutional field knowledge flow network.It provides comprehensive insights into the evolution mechanism of knowledge flow networks in the scientific research realm.The model also exhibits potential applicability to other knowledge networks that involve knowledge organizations as node units.Research Limitations:This study has some limitations.Firstly,it primarily focuses on the evolution of knowledge flow networks within the field of physics,neglecting other fields.Additionally,the analysis is based on a specific set of data,which may limit the generalizability of the findings.Future research could address these limitations by exploring knowledge flow networks in diverse fields and utilizing broader datasets.Practical Implications:The proposed IKM model offers practical implications for the construction and analysis of knowledge flow networks within institutions.It provides a valuable tool for understanding and managing knowledge exchange between knowledge organizations.The model can aid in optimizing knowledge flow and enhancing collaboration within organizations.Originality/value:This research highlights the significance of meso-level studies in understanding knowledge organization and its impact on knowledge flow networks.The IKM model demonstrates its effectiveness in replicating institutional field knowledge flow networks and offers practical implications for knowledge management in institutions.Moreover,the model has the potential to be applied to other knowledge networks,which are formed by knowledge organizations as node units.展开更多
Coastal wetlands are located in the ecotone of interaction between the land surface and sea,and anthropogenic activities extensively interfere with these wetlands through the reclamation of large tidal wetlands and de...Coastal wetlands are located in the ecotone of interaction between the land surface and sea,and anthropogenic activities extensively interfere with these wetlands through the reclamation of large tidal wetlands and destruction of the function of the ecosystems.In this study,we investigated the dynamic evolutionary characteristics of the Bohai Rim coastal area over the past 40 years using the Modified Normalized Difference Water Index,the fractal dimension,object-oriented classification,the land-use transfer trajectory,and regression analysis.Additionally,we quantified and monitored the evolution of reclamation and analyzed the correlation between reclamation and coastal wetlands based on 99 Landsat-2,-5,and-8 images(at 60 m and 30 m spatial resolution) over the period 1980–2019.The results are as follows.(1) The coastline of the Bohai Rim increased by 1 631.2 km from 1980 to2019 with a zigzag variation.The artificial coastline increased by 2 946.1 km,whereas the natural coastline decreased by 90%.(2) The area of man-made wetlands increased by 3 736.9 km~2,the area of construction land increased by 1 008.4 km~2,and the natural wetland area decreased by 66%.The decrease of tidal flats is the main contributor to the decrease of natural wetland area(takes account for 91.1%).Coastal areas are affected by intense human disturbance,which was taken place across a large area of tidal flats and caused the landscape to fragment and be more heterogeneous.The coastal zone development activities were primarily concentrated in the southern Laizhou Bay,the Yellow River Delta,the Bohai Bay,the northern Liaodong Bay,and the Pulandian Bay.The solidified shorelines and increase in sea level have resulted in intertidal wetlands decreasing and impaired wetland ecology.(3) There is a good agreement between reclamation and the size of the coastal wetlands.Both land reclamation and the reduction in coastal wetland areas are significantly related to the population size,fishery output value,and urbanization rate.In summary,human activities,such as the construction of aquaculture ponds and salt pans,industrialization,and urbanization,are the primary forces that influence the environmental changes in the coastal region.This study is beneficial for establishing and improving the systems for the rational development and utilization of natural resources,and provides theoretical references for restoring wetland ecology and managing future reclamation activities in other coastal zone-related areas.展开更多
Crop domestication has fundamentally altered the course of human history,causing a shift from huntergatherer to agricultural societies and stimulating the rise of modern civilization.A greater understanding of crop do...Crop domestication has fundamentally altered the course of human history,causing a shift from huntergatherer to agricultural societies and stimulating the rise of modern civilization.A greater understanding of crop domestication would provide a theoretical basis for how we could improve current crops and develop new crops to deal with environmental challenges in a sustainable manner.Here,we provide a comprehensive summary of the similarities and differences in the domestication processes of maize and rice,two major staple food crops that feed the world.We propose that maize and rice might have evolved distinct genetic solutions toward domestication.Maize and rice domestication appears to be associated with distinct regulatory and evolutionary mechanisms.Rice domestication tended to select de novo,loss-of-function,coding variation,while maize domestication more frequently favored standing,gain-offunction,regulatory variation.At the gene network level,distinct genetic paths were used to acquire convergent phenotypes in maize and rice domestication,during which different central genes were utilized,orthologous genes played different evolutionary roles,and unique genes or regulatory modules were acquired for establishing new traits.Finally,we discuss how the knowledge gained from past domestication processes,together with emerging technologies,could be exploited to improve modern crop breeding and domesticate new crops to meet increasing human demands.展开更多
The low-level jet (LLJ) is closely related to severe rainfall events, air pollution, wind energy utilization, aviation safety, sandstorms, forest fire, and other weather and climate phenomena. Therefore, it has attr...The low-level jet (LLJ) is closely related to severe rainfall events, air pollution, wind energy utilization, aviation safety, sandstorms, forest fire, and other weather and climate phenomena. Therefore, it has attracted considerable attention since its discovery. Scientists have carried out many studies on LLJs and made significant achievements during the past five or six decades. This article summarizes and assesses the current knowledge on this subject, and focuses in particular on three aspects: 1) LLJ classification, definition, distribution, and structure; 2) LLJ formation and evolutionary mechanisms; and 3) relationships between LLJ and rainfall, as well as other interdisciplinary fields. After comparing the status of LLJ research at home (China) and abroad, we then discuss the shortcomings of LLJ research in China. We suggest that this includes: coarse definitions of the LLJ, lack of observations and inadequate quality control, few thorough explorations of LLJ characteristics and formation mechanisms, and limited studies in interdisciplinary fields. The future prospects for several LLJ research avenues are also speculated.展开更多
The rapid development of high-speed rail(HSR) is influencing regional development, regional structure, commuting, and regional integration. East Asia is the region with the world's first and largest current operati...The rapid development of high-speed rail(HSR) is influencing regional development, regional structure, commuting, and regional integration. East Asia is the region with the world's first and largest current operating and planned HSR network. In this paper, we examine the evolutionary mechanism and impacts on the transport circle and accessibility of HSR in East Asia. The results indicate that the HSR network first follows a "core-core" model and then forms a corridor in Japan, South Korea, and China Taiwan, but then forms a complete network in China Mainland. The current operating HSR lines are mostly distributed in regions with developed economies and dense populations, and more than half of the population and GDP in China can be served by HSR within 1 hour's travel time. The planned HSR network will expand to the western region of China and Japan and the southern region of South Korea. The development of the current operating and planned HSR network considerably enlarges the transport circle of core cities, especially cities along trunk HSR lines. This 1 h transport circle of core cities has formed continuous regions in the Yangtze River Delta, the Pearl River Delta, Tokyo, Seoul, and along trunk HSR lines. The HSR network will bring about substantial improvement in accessiblity, but also increase the inequality of nodal accessibility in China Mainland. Spatially, the spatial patterns of the weighted shortest travel time of cities in China Mainland, Japan, and South Korea all present the "core-peripheral structure", taking Zhengzhou, Tokyo, and Seoul, respectively, as core cities, and cities located along the trunk HSR lines gain large improvement in accessibility.展开更多
基金supported by Natural Science Foundation of Chongqing(No.2022NSCQ-MSX4268)National Natural Science Foundation of China(No.22209075).
文摘The battery management system is employed to monitor the external temperature of the lithium-ion battery in order to detect any potential overheating.However,this outside–in detection method often suffers from a lag and is therefore unable to accurately predict the battery’s real-time state.Herein,an inside–out frequency response approach is used to accurately monitor the battery’s state at various temperatures in real-time and correlate it with the solid electrolyte interphase(SEI)evolution of the graphite electrode.The SEI evolution at temperatures of−15,25,60,and 90℃exhibits certain regular characteristics with temperature change.At a temperature of−15℃,the Li^(+)-solvent interaction of lithium-ion slowed down,resulting in a significant reduction in performance.At 25℃,a LiF-rich inorganic SEI was identified as forming,which facilitated lithium-ion transportation.However,high temperatures would induce decomposition of lithium hexafluorophosphate(LiPF_(6))and lithium-ion electrolyte.At the extreme temperature of 90℃,the SEI would be organic-rich,and Li_(x)P_(y)F_(z),a decomposition product of lithium salts,was further oxidized to Li_(x)PO_(y)F_(z),which led to a surge in the charge-transfer resistance at SEI(R_(sei))and a reduction in Coulombic efficiency(CE).This changing relationship can be recorded in real time from the inside out by electrochemical impedance spectroscopy(EIS)testing.This provides a new theoretical basis for the structural evolution of lithium-ion batteries and the regular characterization of EIS.
文摘This paper discusses ancestral hall architecture within the context of the Cantonese folk lineage in the Pearl River Delta.Using a typological research approach and chronological analysis,various factors that have influenced the evolution of ancestral hall architecture are analyzed.The study specifically investigates the features of ancestral halls during the Ming and Qing dynasties.Three periods of ancient China are analyzed:The transition from Ming to Qing,the mid-Qing dynasty,and the late Qing dynasty.The variables of each period and how they influence the evolution of architectural typological features are identified.Based on our analysis,architectural features are related to economic and social factors,materials available,and craftsmanship of the construction workers.
文摘 The Yellow River has a vast catchment area and historically it is the mother river of the Chinese nation. Now it serves as one of the main theatres for the on-going national campaign to develop China's western hinterland.……
基金supported in part by the National Natural Science Foundation of China under Grant 72264036in part by the West Light Foundation of The Chinese Academy of Sciences under Grant 2020-XBQNXZ-020+1 种基金Social Science Foundation of Xinjiang under Grant 2023BGL077the Research Program for High-level Talent Program of Xinjiang University of Finance and Economics 2022XGC041,2022XGC042.
文摘Purpose:This paper aims to address the limitations in existing research on the evolution of knowledge flow networks by proposing a meso-level institutional field knowledge flow network evolution model(IKM).The purpose is to simulate the construction process of a knowledge flow network using knowledge organizations as units and to investigate its effectiveness in replicating institutional field knowledge flow networks.Design/Methodology/Approach:The IKM model enhances the preferential attachment and growth observed in scale-free BA networks,while incorporating three adjustment parameters to simulate the selection of connection targets and the types of nodes involved in the network evolution process Using the PageRank algorithm to calculate the significance of nodes within the knowledge flow network.To compare its performance,the BA and DMS models are also employed for simulating the network.Pearson coefficient analysis is conducted on the simulated networks generated by the IKM,BA and DMS models,as well as on the actual network.Findings:The research findings demonstrate that the IKM model outperforms the BA and DMS models in replicating the institutional field knowledge flow network.It provides comprehensive insights into the evolution mechanism of knowledge flow networks in the scientific research realm.The model also exhibits potential applicability to other knowledge networks that involve knowledge organizations as node units.Research Limitations:This study has some limitations.Firstly,it primarily focuses on the evolution of knowledge flow networks within the field of physics,neglecting other fields.Additionally,the analysis is based on a specific set of data,which may limit the generalizability of the findings.Future research could address these limitations by exploring knowledge flow networks in diverse fields and utilizing broader datasets.Practical Implications:The proposed IKM model offers practical implications for the construction and analysis of knowledge flow networks within institutions.It provides a valuable tool for understanding and managing knowledge exchange between knowledge organizations.The model can aid in optimizing knowledge flow and enhancing collaboration within organizations.Originality/value:This research highlights the significance of meso-level studies in understanding knowledge organization and its impact on knowledge flow networks.The IKM model demonstrates its effectiveness in replicating institutional field knowledge flow networks and offers practical implications for knowledge management in institutions.Moreover,the model has the potential to be applied to other knowledge networks,which are formed by knowledge organizations as node units.
基金The National Social Science Foundation of China under contract No.21BGL026。
文摘Coastal wetlands are located in the ecotone of interaction between the land surface and sea,and anthropogenic activities extensively interfere with these wetlands through the reclamation of large tidal wetlands and destruction of the function of the ecosystems.In this study,we investigated the dynamic evolutionary characteristics of the Bohai Rim coastal area over the past 40 years using the Modified Normalized Difference Water Index,the fractal dimension,object-oriented classification,the land-use transfer trajectory,and regression analysis.Additionally,we quantified and monitored the evolution of reclamation and analyzed the correlation between reclamation and coastal wetlands based on 99 Landsat-2,-5,and-8 images(at 60 m and 30 m spatial resolution) over the period 1980–2019.The results are as follows.(1) The coastline of the Bohai Rim increased by 1 631.2 km from 1980 to2019 with a zigzag variation.The artificial coastline increased by 2 946.1 km,whereas the natural coastline decreased by 90%.(2) The area of man-made wetlands increased by 3 736.9 km~2,the area of construction land increased by 1 008.4 km~2,and the natural wetland area decreased by 66%.The decrease of tidal flats is the main contributor to the decrease of natural wetland area(takes account for 91.1%).Coastal areas are affected by intense human disturbance,which was taken place across a large area of tidal flats and caused the landscape to fragment and be more heterogeneous.The coastal zone development activities were primarily concentrated in the southern Laizhou Bay,the Yellow River Delta,the Bohai Bay,the northern Liaodong Bay,and the Pulandian Bay.The solidified shorelines and increase in sea level have resulted in intertidal wetlands decreasing and impaired wetland ecology.(3) There is a good agreement between reclamation and the size of the coastal wetlands.Both land reclamation and the reduction in coastal wetland areas are significantly related to the population size,fishery output value,and urbanization rate.In summary,human activities,such as the construction of aquaculture ponds and salt pans,industrialization,and urbanization,are the primary forces that influence the environmental changes in the coastal region.This study is beneficial for establishing and improving the systems for the rational development and utilization of natural resources,and provides theoretical references for restoring wetland ecology and managing future reclamation activities in other coastal zone-related areas.
基金This work was supported by the National Natural Science Foundation of China(32025027 and 31971892)the National Key Research and Exploiting Maize and Rice Domestication Development Program of China(2016YFD0100303)the Recruitment Program of Global Experts,and the Fundamental Research Funds for the Central Universities to F.T.Q.C.was supported by US NSF grant IOS 1934865 to John Doebley.
文摘Crop domestication has fundamentally altered the course of human history,causing a shift from huntergatherer to agricultural societies and stimulating the rise of modern civilization.A greater understanding of crop domestication would provide a theoretical basis for how we could improve current crops and develop new crops to deal with environmental challenges in a sustainable manner.Here,we provide a comprehensive summary of the similarities and differences in the domestication processes of maize and rice,two major staple food crops that feed the world.We propose that maize and rice might have evolved distinct genetic solutions toward domestication.Maize and rice domestication appears to be associated with distinct regulatory and evolutionary mechanisms.Rice domestication tended to select de novo,loss-of-function,coding variation,while maize domestication more frequently favored standing,gain-offunction,regulatory variation.At the gene network level,distinct genetic paths were used to acquire convergent phenotypes in maize and rice domestication,during which different central genes were utilized,orthologous genes played different evolutionary roles,and unique genes or regulatory modules were acquired for establishing new traits.Finally,we discuss how the knowledge gained from past domestication processes,together with emerging technologies,could be exploited to improve modern crop breeding and domesticate new crops to meet increasing human demands.
基金Supported by the National Natural Science Foundation of China(40905049)China Meteorological Administration Special Public Welfare Research Fund(GYHY201306016 and GYHY200906020)
文摘The low-level jet (LLJ) is closely related to severe rainfall events, air pollution, wind energy utilization, aviation safety, sandstorms, forest fire, and other weather and climate phenomena. Therefore, it has attracted considerable attention since its discovery. Scientists have carried out many studies on LLJs and made significant achievements during the past five or six decades. This article summarizes and assesses the current knowledge on this subject, and focuses in particular on three aspects: 1) LLJ classification, definition, distribution, and structure; 2) LLJ formation and evolutionary mechanisms; and 3) relationships between LLJ and rainfall, as well as other interdisciplinary fields. After comparing the status of LLJ research at home (China) and abroad, we then discuss the shortcomings of LLJ research in China. We suggest that this includes: coarse definitions of the LLJ, lack of observations and inadequate quality control, few thorough explorations of LLJ characteristics and formation mechanisms, and limited studies in interdisciplinary fields. The future prospects for several LLJ research avenues are also speculated.
基金National Natural Science Foundation of China,No.41171107,No.41371143,No.4401121
文摘The rapid development of high-speed rail(HSR) is influencing regional development, regional structure, commuting, and regional integration. East Asia is the region with the world's first and largest current operating and planned HSR network. In this paper, we examine the evolutionary mechanism and impacts on the transport circle and accessibility of HSR in East Asia. The results indicate that the HSR network first follows a "core-core" model and then forms a corridor in Japan, South Korea, and China Taiwan, but then forms a complete network in China Mainland. The current operating HSR lines are mostly distributed in regions with developed economies and dense populations, and more than half of the population and GDP in China can be served by HSR within 1 hour's travel time. The planned HSR network will expand to the western region of China and Japan and the southern region of South Korea. The development of the current operating and planned HSR network considerably enlarges the transport circle of core cities, especially cities along trunk HSR lines. This 1 h transport circle of core cities has formed continuous regions in the Yangtze River Delta, the Pearl River Delta, Tokyo, Seoul, and along trunk HSR lines. The HSR network will bring about substantial improvement in accessiblity, but also increase the inequality of nodal accessibility in China Mainland. Spatially, the spatial patterns of the weighted shortest travel time of cities in China Mainland, Japan, and South Korea all present the "core-peripheral structure", taking Zhengzhou, Tokyo, and Seoul, respectively, as core cities, and cities located along the trunk HSR lines gain large improvement in accessibility.