For researching the spatio-temporal variation of the stable isotopic composition of the riverine dissolved inorganic carbon(DIC),we had carried out a survey throughout the hydrologic year during which theδ^13CDIC o...For researching the spatio-temporal variation of the stable isotopic composition of the riverine dissolved inorganic carbon(DIC),we had carried out a survey throughout the hydrologic year during which theδ^13CDIC of the surface water and its physicochemical parameter were examined along the Xijiang River Inner Estuarine waterway from September 2006 to June 2007.There was a striking seasonal variation on the averageδ^13CDIC,as the averageδ^13CDIC in summer(-13.91‰)or autumn(-13.09‰)was much less than those in spring(-11.71‰)or winter(-12.26‰).The riverineδ13C DIC was controlled by decomposed condition of the riverine organic matter linking the seasonal variation of the physicochemical parameter in the surface water according to the correlation analysis which indicated notable relations betweenδ^13CDIC and water temperature(p=0.000;r=-0.569)or betweenδ^13CDIC and oxide-reduction potential(p=0.000;r=0.646).The striking positive correlation between δ^13CDIC and the sampling distance happened in the summer rainy season,while striking negative correlation happened in the spring dry season,indicating that river-sea interaction influenced water physicochemical parameters and controlled the riverine DIC property in the survey waterway.In view of the riverineδ^13CDIC decreasing for the decomposition of the terrestrial organic matter in the rainy season in summer and increasing for the briny invaded zone extending in the spring dry season along the waterway from the Makou gauging station to the Modaomen outlet,theδ^13CDIC spatio-temporal variation was closely related to the geographical environment of the Xijiang drainage basin.展开更多
Dike failure caused by overtopping is likely to result in major casualties and property losses.Aiming at this fact,a series of physical model experiments were conducted on stable thickness of masonry block on the inne...Dike failure caused by overtopping is likely to result in major casualties and property losses.Aiming at this fact,a series of physical model experiments were conducted on stable thickness of masonry block on the inner slope of the dike.According to the erosion of block embankment with different thicknesses,the relation between the stable thickness of masonry block pitching of the inner slope and the average overtopping discharge is discussed.New equations subject to irregular waves are presented for average overtopping discharge,based upon the analysis of mean overtopping discharge and comparison of present overtopping discharge formulas at domestic and abroad.Finally,a calculation equation of the stable thickness of the dry masonry block stone of inner slope subject to irregular waves is given.In conclusion,the formula matches well with the experiment result,which is capable of functioning as an important reference for structure designs of the dike in China.展开更多
Rechargeable lithium metal batteries own the highest energy density among all electrochemical energy storage devices.Lithium metal anode in those cell system acts as paramount role in promoting high energy density[1]....Rechargeable lithium metal batteries own the highest energy density among all electrochemical energy storage devices.Lithium metal anode in those cell system acts as paramount role in promoting high energy density[1].However,lithium anode tends to form dendrite morphology and exhibits huge volume expansion and high reactivity,which induces ultra-low columbic efficiency and out of tolerance cycle performance and even safety hazards[2,3].The lithium dendrite growth behavior is mainly decided by the high surface energy and diffusion barriers for Li ions in lithium batteries which is ascribed to thermodynamics factors and uneven electronic field distribution[1,4,5].During the repeated plating/stripping process,the structure and components of solid–liquid interphase are significantly determined by the deposition thermodynamics and kinetics.In the recent years,advances in characterization technology and the development of high-performance computing method have driven the rapid exploration of the fundamental theory of solid–liquid interphase in lithium batteries.展开更多
Central-south Inner Mongolia, China, is highly sensitive to the cultural interactions between sedentary agriculturalists and nomadic pastoralists during the Eastern Zhou Period(770–256 BC). The previous pattern of mu...Central-south Inner Mongolia, China, is highly sensitive to the cultural interactions between sedentary agriculturalists and nomadic pastoralists during the Eastern Zhou Period(770–256 BC). The previous pattern of multiple cultures and diverse ethnic groups has been transformed to the increasingly dominated cultural system of Central Plain since the middle and late Warring States Period, when the states of Zhao and Qin have conquered the most parts of central-south Inner Mongolia.However, the variation of subsistence strategies during this historical process has never been evaluated. Particularly, as the typical representative of Central Plain cultures, the effect of intensive millet agriculture is still unknown in the process of population integration and culture interaction. Thus, to explore the shift of subsistence pattern, carbon and nitrogen stable isotope analysis of bone collagen from Dabaoshan site(410–180 BC) have been performed. The isotopic result indicates a large amount of C_4-based animal protein consumed by Dabaoshan humans. According to the archaeological backgrounds, we propose the Dabaoshan persons intensively relied on the millet agriculture and developed the agro-pastoral economy, which hinted the comprehensive influences from Central plain civilizations in late Warring States Period. Further compared with other published isotopic data in the same region during different periods, we suggest the millet agriculture has played the positive role in the process of population integration and culture fusion in central-south Inner Mongolia during the Eastern Zhou Period.展开更多
基金National Natural Science Foundation of China, No.40671027 No.40471120+2 种基金 Guangdong Provincial Natural Science Foundation, No.7003669 Specialized Research Fund for the Doctoral Program of Higher Education, No.20040558025 The Program for New Century Excellent Talents in University
文摘For researching the spatio-temporal variation of the stable isotopic composition of the riverine dissolved inorganic carbon(DIC),we had carried out a survey throughout the hydrologic year during which theδ^13CDIC of the surface water and its physicochemical parameter were examined along the Xijiang River Inner Estuarine waterway from September 2006 to June 2007.There was a striking seasonal variation on the averageδ^13CDIC,as the averageδ^13CDIC in summer(-13.91‰)or autumn(-13.09‰)was much less than those in spring(-11.71‰)or winter(-12.26‰).The riverineδ13C DIC was controlled by decomposed condition of the riverine organic matter linking the seasonal variation of the physicochemical parameter in the surface water according to the correlation analysis which indicated notable relations betweenδ^13CDIC and water temperature(p=0.000;r=-0.569)or betweenδ^13CDIC and oxide-reduction potential(p=0.000;r=0.646).The striking positive correlation between δ^13CDIC and the sampling distance happened in the summer rainy season,while striking negative correlation happened in the spring dry season,indicating that river-sea interaction influenced water physicochemical parameters and controlled the riverine DIC property in the survey waterway.In view of the riverineδ^13CDIC decreasing for the decomposition of the terrestrial organic matter in the rainy season in summer and increasing for the briny invaded zone extending in the spring dry season along the waterway from the Makou gauging station to the Modaomen outlet,theδ^13CDIC spatio-temporal variation was closely related to the geographical environment of the Xijiang drainage basin.
基金Supported by the National Key R&D Program of China(No.2016YFC1402002)the National Natural Science Foundation of China(No.51579156)the Major Project of Nanjing Hydraulic Research Institute Funds(Nos.Y218005,Y218006)
文摘Dike failure caused by overtopping is likely to result in major casualties and property losses.Aiming at this fact,a series of physical model experiments were conducted on stable thickness of masonry block on the inner slope of the dike.According to the erosion of block embankment with different thicknesses,the relation between the stable thickness of masonry block pitching of the inner slope and the average overtopping discharge is discussed.New equations subject to irregular waves are presented for average overtopping discharge,based upon the analysis of mean overtopping discharge and comparison of present overtopping discharge formulas at domestic and abroad.Finally,a calculation equation of the stable thickness of the dry masonry block stone of inner slope subject to irregular waves is given.In conclusion,the formula matches well with the experiment result,which is capable of functioning as an important reference for structure designs of the dike in China.
文摘Rechargeable lithium metal batteries own the highest energy density among all electrochemical energy storage devices.Lithium metal anode in those cell system acts as paramount role in promoting high energy density[1].However,lithium anode tends to form dendrite morphology and exhibits huge volume expansion and high reactivity,which induces ultra-low columbic efficiency and out of tolerance cycle performance and even safety hazards[2,3].The lithium dendrite growth behavior is mainly decided by the high surface energy and diffusion barriers for Li ions in lithium batteries which is ascribed to thermodynamics factors and uneven electronic field distribution[1,4,5].During the repeated plating/stripping process,the structure and components of solid–liquid interphase are significantly determined by the deposition thermodynamics and kinetics.In the recent years,advances in characterization technology and the development of high-performance computing method have driven the rapid exploration of the fundamental theory of solid–liquid interphase in lithium batteries.
基金supported by National Natural Science Foundation of China (Grant No. 41373018)National Social Science Foundation of China (Grant No. 10CKG001)
文摘Central-south Inner Mongolia, China, is highly sensitive to the cultural interactions between sedentary agriculturalists and nomadic pastoralists during the Eastern Zhou Period(770–256 BC). The previous pattern of multiple cultures and diverse ethnic groups has been transformed to the increasingly dominated cultural system of Central Plain since the middle and late Warring States Period, when the states of Zhao and Qin have conquered the most parts of central-south Inner Mongolia.However, the variation of subsistence strategies during this historical process has never been evaluated. Particularly, as the typical representative of Central Plain cultures, the effect of intensive millet agriculture is still unknown in the process of population integration and culture interaction. Thus, to explore the shift of subsistence pattern, carbon and nitrogen stable isotope analysis of bone collagen from Dabaoshan site(410–180 BC) have been performed. The isotopic result indicates a large amount of C_4-based animal protein consumed by Dabaoshan humans. According to the archaeological backgrounds, we propose the Dabaoshan persons intensively relied on the millet agriculture and developed the agro-pastoral economy, which hinted the comprehensive influences from Central plain civilizations in late Warring States Period. Further compared with other published isotopic data in the same region during different periods, we suggest the millet agriculture has played the positive role in the process of population integration and culture fusion in central-south Inner Mongolia during the Eastern Zhou Period.