The Pearl River Mouth Basin(PRMB)is one of the most petroliferous basins on the northern margin of the South China Sea.Knowledge of the thermal history of the PRMB is significant for understanding its tectonic evoluti...The Pearl River Mouth Basin(PRMB)is one of the most petroliferous basins on the northern margin of the South China Sea.Knowledge of the thermal history of the PRMB is significant for understanding its tectonic evolution and for unraveling its poorly studied source-rock maturation history.Our investigations in this study are based on apatite fission-track(AFT)thermochronology analysis of 12 cutting samples from 4 boreholes.Both AFT ages and length data suggested that the PRMB has experienced quite complicated thermal evolution.Thermal history modeling results unraveled four successive events of heating separated by three stages of cooling since the early Middle Eocene.The cooling events occurred approximately in the Late Eocene,early Oligocene,and the Late Miocene,possibly attributed to the Zhuqiong II Event,Nanhai Event,and Dongsha Event,respectively.The erosion amount during the first cooling stage is roughly estimated to be about 455-712 m,with an erosion rate of 0.08-0.12 mm/a.The second erosion-driven cooling is stronger than the first one,with an erosion amount of about 747-814 m and an erosion rate between about 0.13-0.21 mm/a.The erosion amount calculated related to the third cooling event varies from 800 m to 3419 m,which is speculative due to the possible influence of the magmatic activity.展开更多
In the late Ming period,Xu Guangqi and other Catholic literati were actively involved with military affairs because of the invasion of the Manchu forces and the threat of uprisings.The story of how they imported Europ...In the late Ming period,Xu Guangqi and other Catholic literati were actively involved with military affairs because of the invasion of the Manchu forces and the threat of uprisings.The story of how they imported European cannons and gunners from Macao is now quite famous.However,the introduction of European fortifications,mainly the trace Italienne,in the same period is still relatively unknown.Xu Guangqi and his student Sun Yuanhua exerted considerable efforts in advocating European-style bastions.Xu not only received help from Jesuits,but also support from some Fujianese who were familiar with Intramuros,the Spanish walled city of Manila.In addition to Xu and Sun,Han Lin and Han Yun(also Xu’s students)prepared a Chinese treatise on European fortification architecture based on Italian sources and tried to put the knowledge into practice.Another relevant figure is Ma Weicheng,who allegedly directed the building of 32 angled bastions in three cities around 1640.Although a few recorded writings and practices of constructing European-style fortification appeared in the first half of the seventeenth century,soon afterwards the art of trace Italienne met its end prematurely in China.To a great extent,the swift collapse of the Ming dynasty eliminated the possibility of spreading the new defense technology.Throughout the eighteenth century,the Qing dynasty enjoyed long-term peace,and the warfare at the frontiers brought few threats to the city walls.There was thus little urgency to develop innovative defensive works and European fortification sunk into oblivion until the mid-nineteenth century.展开更多
The cause of substorm onset is not yet understood. Chen CX(2016) proposed an entropy switch model, in which substorm onset results from the development of interchange instability. In this study, we sought observationa...The cause of substorm onset is not yet understood. Chen CX(2016) proposed an entropy switch model, in which substorm onset results from the development of interchange instability. In this study, we sought observational evidence for this model by using Time History of Events and Macroscale Interactions during Substorms(THEMIS) data. We examined two events, one with and the other without a streamer before substorm onset. In contrast to the stable magnetosphere, where the total magnetic field strength is a decreasing function and entropy is an increasing function of the downtail distance, in both events the total magnetic field strength and entropy were reversed before substorm onset. After onset, the total magnetic field strength, entropy, and other plasma quantities fluctuated. In addition, a statistical study was performed. By confining the events with THEMIS satellites located in the downtail region between ~8 and ~12 Earth radii, and 3 hours before and after midnight, we found the occurrence rate of the total magnetic field strength reversal to be 69% and the occurrence rate of entropy reversal to be 77% of the total 205 events.展开更多
This essay examines current-event plays( shishiju 时事剧) and their social functions in late Ming China. Drawing on awide range or primary sources and built on secondary scholarship on information history,the essay of...This essay examines current-event plays( shishiju 时事剧) and their social functions in late Ming China. Drawing on awide range or primary sources and built on secondary scholarship on information history,the essay offered a complete picture of the booming,features,social functions and the decline of the current-event plays. The essay argues that many current-event plays addressed on credibility,timeliness and easy accessibility,which enabled current-event plays to play an important role in information circulation. This essay further exposes the current-event plays not only opened a forum for public discussion but also influenced public opinions greatly from literate elites to the masses in Ming China. Through analyzing current-event plays in the context of Ming society,this essay expands the realm of studying information history.展开更多
The Ming dynasty (13681644) inherited the long-standing culture in China, of course including the textile technology. Besides a large amount of single color damask silk, many pattern woven silk including dragon robes,...The Ming dynasty (13681644) inherited the long-standing culture in China, of course including the textile technology. Besides a large amount of single color damask silk, many pattern woven silk including dragon robes, patterned costumes and luxurious silk textiles are found in complicated and colorful pattern woven brocade called zhuang hua. It was prevailed in Ming dynasty when compared with the frequency of the name zhuang hua recorded in related historical documents. These pattern silk and brocade were produced by the advanced pattern weaving technology, which was well developed in Ming dynasty. From historical documents of “Tian gong kai wu”, Exploitation of the works of nature, there is the detailed description of the draw loom (hua lo ji) which can weave normal patterned textiles. It also indicated that to produce dragon robes needed much more high technique, similar to the hua lo ji but more complicated and difficult. A big draw loom is found to weave Nanjing Yun brocade today inherits the technology to weave zhuang hua brocade. After sorting the historical documents, it is found that some records are coincident with the existed materials, both the silk textiles and weaving technology. With these evidences research and exploration, this dissertation tries to unravel the pattern weaving technology in the Ming dynasty.展开更多
基金This study is financially supported by the National Natural Science Foundation of China(42072181).
文摘The Pearl River Mouth Basin(PRMB)is one of the most petroliferous basins on the northern margin of the South China Sea.Knowledge of the thermal history of the PRMB is significant for understanding its tectonic evolution and for unraveling its poorly studied source-rock maturation history.Our investigations in this study are based on apatite fission-track(AFT)thermochronology analysis of 12 cutting samples from 4 boreholes.Both AFT ages and length data suggested that the PRMB has experienced quite complicated thermal evolution.Thermal history modeling results unraveled four successive events of heating separated by three stages of cooling since the early Middle Eocene.The cooling events occurred approximately in the Late Eocene,early Oligocene,and the Late Miocene,possibly attributed to the Zhuqiong II Event,Nanhai Event,and Dongsha Event,respectively.The erosion amount during the first cooling stage is roughly estimated to be about 455-712 m,with an erosion rate of 0.08-0.12 mm/a.The second erosion-driven cooling is stronger than the first one,with an erosion amount of about 747-814 m and an erosion rate between about 0.13-0.21 mm/a.The erosion amount calculated related to the third cooling event varies from 800 m to 3419 m,which is speculative due to the possible influence of the magmatic activity.
文摘In the late Ming period,Xu Guangqi and other Catholic literati were actively involved with military affairs because of the invasion of the Manchu forces and the threat of uprisings.The story of how they imported European cannons and gunners from Macao is now quite famous.However,the introduction of European fortifications,mainly the trace Italienne,in the same period is still relatively unknown.Xu Guangqi and his student Sun Yuanhua exerted considerable efforts in advocating European-style bastions.Xu not only received help from Jesuits,but also support from some Fujianese who were familiar with Intramuros,the Spanish walled city of Manila.In addition to Xu and Sun,Han Lin and Han Yun(also Xu’s students)prepared a Chinese treatise on European fortification architecture based on Italian sources and tried to put the knowledge into practice.Another relevant figure is Ma Weicheng,who allegedly directed the building of 32 angled bastions in three cities around 1640.Although a few recorded writings and practices of constructing European-style fortification appeared in the first half of the seventeenth century,soon afterwards the art of trace Italienne met its end prematurely in China.To a great extent,the swift collapse of the Ming dynasty eliminated the possibility of spreading the new defense technology.Throughout the eighteenth century,the Qing dynasty enjoyed long-term peace,and the warfare at the frontiers brought few threats to the city walls.There was thus little urgency to develop innovative defensive works and European fortification sunk into oblivion until the mid-nineteenth century.
基金supported by the National Natural Science Foundation of China(Grant No.NSFC41974204)。
文摘The cause of substorm onset is not yet understood. Chen CX(2016) proposed an entropy switch model, in which substorm onset results from the development of interchange instability. In this study, we sought observational evidence for this model by using Time History of Events and Macroscale Interactions during Substorms(THEMIS) data. We examined two events, one with and the other without a streamer before substorm onset. In contrast to the stable magnetosphere, where the total magnetic field strength is a decreasing function and entropy is an increasing function of the downtail distance, in both events the total magnetic field strength and entropy were reversed before substorm onset. After onset, the total magnetic field strength, entropy, and other plasma quantities fluctuated. In addition, a statistical study was performed. By confining the events with THEMIS satellites located in the downtail region between ~8 and ~12 Earth radii, and 3 hours before and after midnight, we found the occurrence rate of the total magnetic field strength reversal to be 69% and the occurrence rate of entropy reversal to be 77% of the total 205 events.
文摘This essay examines current-event plays( shishiju 时事剧) and their social functions in late Ming China. Drawing on awide range or primary sources and built on secondary scholarship on information history,the essay offered a complete picture of the booming,features,social functions and the decline of the current-event plays. The essay argues that many current-event plays addressed on credibility,timeliness and easy accessibility,which enabled current-event plays to play an important role in information circulation. This essay further exposes the current-event plays not only opened a forum for public discussion but also influenced public opinions greatly from literate elites to the masses in Ming China. Through analyzing current-event plays in the context of Ming society,this essay expands the realm of studying information history.
文摘The Ming dynasty (13681644) inherited the long-standing culture in China, of course including the textile technology. Besides a large amount of single color damask silk, many pattern woven silk including dragon robes, patterned costumes and luxurious silk textiles are found in complicated and colorful pattern woven brocade called zhuang hua. It was prevailed in Ming dynasty when compared with the frequency of the name zhuang hua recorded in related historical documents. These pattern silk and brocade were produced by the advanced pattern weaving technology, which was well developed in Ming dynasty. From historical documents of “Tian gong kai wu”, Exploitation of the works of nature, there is the detailed description of the draw loom (hua lo ji) which can weave normal patterned textiles. It also indicated that to produce dragon robes needed much more high technique, similar to the hua lo ji but more complicated and difficult. A big draw loom is found to weave Nanjing Yun brocade today inherits the technology to weave zhuang hua brocade. After sorting the historical documents, it is found that some records are coincident with the existed materials, both the silk textiles and weaving technology. With these evidences research and exploration, this dissertation tries to unravel the pattern weaving technology in the Ming dynasty.
