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娘惹文化的影视剧建构与区域化传播 被引量:1
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作者 彭雨晴 海诚 《中华女子学院学报》 2022年第1期80-86,共7页
海外华人文学和艺术作品大多离不开文化认同和时代感召下的进步意识问题,而教育、语言、服饰、饮食等层面都是体现这两个命题的主要维度。就此而言,娘惹形象的建构则更容易在上述维度找到切入点。以娘惹影视剧传播为例,通过对教育、语... 海外华人文学和艺术作品大多离不开文化认同和时代感召下的进步意识问题,而教育、语言、服饰、饮食等层面都是体现这两个命题的主要维度。就此而言,娘惹形象的建构则更容易在上述维度找到切入点。以娘惹影视剧传播为例,通过对教育、语言、服饰、饮食等层面的展示,表现出“娘惹”与中华文化既亲近又疏离的矛盾,反映了海外华人文化根性焦虑本质。娘惹文化正在经历以下三方面的调适:一是在全球化过程中始终坚守自身的文化内核,二是凭借丰富的传播形式以适应不同时代的审美需求,三是擅长借鉴各国优秀文化因子。这种调试为娘惹文化的在地书写和区域传播做出了开拓性实践,也为影视剧对华人女性文化的建构与传播实践提供了参考经验。 展开更多
关键词 娘惹文化 文化认同 文化疏离 在地书写 区域化传播
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Catalytic hydrotreatment of humins into cyclic hydrocarbons over solid acid supported metal catalysts in cyclohexane
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作者 Junmin Sun hai cheng +5 位作者 Yao Zhang Yinmin Zhang Xunfeng Lan Yongfeng Zhang Qineng Xia Daqian Ding 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期329-339,I0011,共12页
Humins are common undesirable sideproducts during many acid-catalyzed reactions in renewable biomass platform conversion. However, few studies have been reported to the efficient utilization of humins.For the first ti... Humins are common undesirable sideproducts during many acid-catalyzed reactions in renewable biomass platform conversion. However, few studies have been reported to the efficient utilization of humins.For the first time, the selective catalytic conversion of biomass-derived humins into cyclic hydrocarbons with high conversion rate and selectivity is presented using a home-made Ru/W-P-Si-O bifunctional catalyst. The multistage polymerization structure of humins was studied through controlled experiments.Results show that the CAC bond network can be efficiently depolymerized at a mild reaction temperature of 340–380 °C, catalyzed by the cooperative catalysis of nano-Ru particles and porous strong Lewis solid acid. Particularly, 95.4% conversion of humins was achieved under the optimal condition with up to 88.3%yield of cyclic hydrocarbons. The detailed composition after liquefaction was also analyzed. This study paves the way for the efficient production of cyclic and aromatic hydrocarbons from furan-derived humin polymer through Lewis acid-catalyzed Diels–Alder reactions between furan rings. 展开更多
关键词 Humins HYDROTREATMENT HYDRODEOXYGENATION Bifunctional catalyst Diels–Alder reaction Retro aldol condensation
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Understanding Interannual Variations of the Local Rainy Season over the Southwest Indian Ocean
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作者 Hanying LI Peng HU +2 位作者 Qiong ZHANG Ashish SINHA hai cheng 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第11期1852-1862,共11页
Located at the southern boundary of the tropical rainfall belt within the South Africa monsoon regime,Rodrigues Island,~2500 km east of East Africa,is ideally located to investigate climatic changes over the southwest... Located at the southern boundary of the tropical rainfall belt within the South Africa monsoon regime,Rodrigues Island,~2500 km east of East Africa,is ideally located to investigate climatic changes over the southwest Indian Ocean(SWIO).In this study,we investigate the climatic controls of its modern interannual rainfall variability in terms of teleconnection and local effects.We find that increased rainfall over the SWIO tends to occur in association with anomalously warm(cold)SSTs over the equatorial central Pacific(Maritime Continent),resembling the central Pacific El Niño,closely linked with the Victoria mode in the North Pacific.Our analyses show that the low-level convergence induced by warm SST over the equatorial central Pacific leads to anomalous low-level divergence over the Maritime Continent and convergence over a large area surrounding the Rodrigues Island,which leads to increased rainfall over the SWIO during the rainy season.Meanwhile,the excited Rossby wave along the tropical Indian Ocean transports more water vapor from the tropical convergence zone into the SWIO via intensified northwest wind.Furthermore,positive feedback induced by the Rossby wave response to the increased rainfall in the region contributes to the large interannual variations over the SWIO. 展开更多
关键词 southwest Indian Ocean interannual rainfall variability PACIFIC Walker Circulation Rossby wave positive feedback
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The Water Problem and Its Solution in Gansu, China
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作者 Yuke Li Luyi Wang hai cheng 《Applied Mathematics》 2017年第10期1515-1528,共14页
Based on such severe situation, we need to work out a way that enables us to analyze the current and future ability of a region to provide clean water to meet the needs of its population, and to develop a reasonable s... Based on such severe situation, we need to work out a way that enables us to analyze the current and future ability of a region to provide clean water to meet the needs of its population, and to develop a reasonable strategy to optimize the utilization of water resources in this area. This paper has worked out a resolution model and input the data of China, the United States, Russia, Laos and Afghanistan to do national testing. Then, we use the policy from “diaper incident” to do policy testing. The calculation results of the model are in conformity with the reality. Therefore, the model is effective. At last this model is used to resolve Gansu’s water problem and provide effective advices for the local government. 展开更多
关键词 WATER SCARCITY WATER Supply EFFECT China RESOURCES PROBLEMS
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An annually laminated stalagmite from the eastern Qinghai-Tibetan Plateau provides evidence of climate instability during the early MIS5e in the Asian summer monsoon
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作者 Tao GAO Pingzhong ZHANG +7 位作者 hai cheng Leilei ZHANG Xinhu LI Hongyu SHI Wei JIA Youfeng NING Hanying LI R.Lawrence EDWARDS 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第5期1147-1164,共18页
The Marine Isotope Stage(MIS5e)is characterized by a warmer climate than that of the pre-industrial period,and serves as an analog for the Current Warm Period(CWP).However,uncertainties persist regarding its climatic ... The Marine Isotope Stage(MIS5e)is characterized by a warmer climate than that of the pre-industrial period,and serves as an analog for the Current Warm Period(CWP).However,uncertainties persist regarding its climatic stability.Here,we retrieved a stalagmite(WXB075)from Wanxiang Cave in the eastern Qinghai-Tibetan Plateau,and employed abs-olute^(230)Th dating and relative annual layer data to establish a high-precision chronological framework for reconstructing the history of the Asian summer monsoon(ASM)and environmental evolution during early MIS5e with multiple proxies.The findings indicate that the annually laminated stalagmite was formed during Cooling Event 27(C27).The deposition of WXB075 experienced a hiatus(~125.58 ka BP)due to a significant cooling event in the North Atlantic,which may be linked to the unstable climate in the Northern Hemisphere.Additionally,the impact of meltwater discharge in high northern latitudes results in a two-phase evolution of the ASM,i.e.,an initial weaker stage followed by a gradual increase(with exception of deposition hiatus).The climatic instability of ASM is generally characterized by a quasi-60 year cycle that affects vegetation conditions,biological productivity,and karst hydroclimate dynamics.However,the increase in meltwater and decrease in temperature in the Northern Hemisphere have led to a weakened ASM and subsequent reduction in precipitation.Consequently,vegetation degradation above the cave has occurred along with a slowdown of karst hydroclimate.The vegetation conditions,organic matter content,and wet/drought of the karst hydroclimate were affected by both the large-scale monsoon circulation and local environment during extreme weakening(strengthening)of the monsoon when high-frequency climatic events of ASM occurred.A comparison ofδ^(18)O records between early MIS5e and the past 2000 years reveals that the climate during early MIS5e differed significantly from that of CWP,Medieval Warm Period(MWP),and Dark Age Cold Period(DACP)but was similar to Little Ice Age(LIA).Comparison with other geological records from the Northern Hemisphere indicates that climate instability was a widespread phenomenon during MIS5e.The power spectrum analysis of WXB075δ^(18)O reveals significant quasi-60 and 35 a cycles during the early MIS5e,which is consistent with the Atlantic Multidecadal Oscillation(AMO).The comprehensive results demonstrate that the ASM in the early MIS5e was closely linked to solar activity,Intertropical Convergence Zone(ITCZ)position,and Atlantic Meridional Overturning Circulation(AMOC). 展开更多
关键词 Eastern Qinghai-Tibetan Plateau Climate instability Wanxiang Cave stalagmite Asian summer monsoon Environmental response Deposition hiatus
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Harnessing science,technology,and innovation to drive synergy between climate goals and the SDGs
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作者 Lei Huang Ranjula Bali Swain +11 位作者 Erik Jeppesen hai cheng Panmao Zhai Baojing Gu DamiàBarceló Jianhua Lu Ke Wei Lei Luo Fang Wang haijun Wang Jiangyuan Zeng Huadong Guo 《The Innovation》 EI 2024年第6期1-2,共2页
The United Nations passed two important resolutions,Transforming our World:The 2030 Agenda for Sustainable Development and the Paris Agreement,in 2015 to change our world.The 17 Sustainable Development Goals(SDGs)were... The United Nations passed two important resolutions,Transforming our World:The 2030 Agenda for Sustainable Development and the Paris Agreement,in 2015 to change our world.The 17 Sustainable Development Goals(SDGs)were adopted as the core of the 2030 Agenda for Sustainable Development,which set out a 15-year plan to achieve the goals. 展开更多
关键词 SUSTAINABLE SDGs HARNESS
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Chinese stalagmite paleoclimate researches: A review and perspective 被引量:19
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作者 hai cheng haiwei ZHANG +3 位作者 Jingyao ZHAO Hanying LI Youfeng NING Gayatri KATHAYAT 《Science China Earth Sciences》 SCIE EI CAS CSCD 2019年第10期1489-1513,共25页
Stalagmite is one kind of secondary carbonates formed in limestone caves(speleothem). After cave water droplets containing Ca2+and HCO3 drip onto floor, carbonate in the water might become supersaturated due to CO2 de... Stalagmite is one kind of secondary carbonates formed in limestone caves(speleothem). After cave water droplets containing Ca2+and HCO3 drip onto floor, carbonate in the water might become supersaturated due to CO2 degassing under certain conditions, resulting in the formation of stalagmite in a process year after year. Stalagmite is one of important geological archives for paleoclimate research. The advantages include wide spatial distribution, suitable for U-Th and U-Pb dating, enriched in climate proxies, continuity, long time span, comparability and lower sampling cost etc. These factors have propelled stalagmite paleoclimate research to the forefront of global paleoclimatology with an irreplaceable role. The stalagmite paleoclimate study started in the western countries, mainly in Europe and America in 1960 s–1970 s, while the relevant research in China was progressively developed in the 1980 s–1990 s after the Reform and Opening up. Although there was a huge gap between the overall research level in China and western countries, a solid research foundation, as well as a number of talent teams were established during the period. In the 21 st century, starting from the publication of stalagmite records from Hulu Cave in Nanjing in 2001, the stalagmite paleoclimate research in China has ushered in a flourishing development and a real leap on the basis of international cooperation, resulting in significant international impacts. The landmark achievements, including establishment of the world’s longest(640000 years) East Asian monsoon stalagmite record, as well as the longest Indian monsoon(280000 years),South American monsoon(250000 years), North American westerly climate(330000 years), Central Asian westerly climate(135000 years), and northwestern China westerly climate(500000 years), have laid a milestone in the paleoclimate study in these climate domains. Importantly, these stalagmite records have revealed the relationship of Asian monsoon variations with solar insolation climate change in polar regions, and the South American monsoon changes on orbital-suborbital timescales, which have provided new geological observations for the development of orbital-suborbital climate theory;elaborated coupling and differentiation relationships between the Asian monsoon and the westerly climate;reconstructed the history of Asian monsoon changes in the Holocene in detail, and thus the hydrological and climate variances behind Chinese and Indian civilizationcultural evolutions. Furthermore, a large number of high-resolution stalagmite records over the past 2000 years have been reconstructed, which are important for understanding short-term climate variability and magnitude, events, cycles, and thus the future climate projection. The achievements have also involved the improvements of a number of important techniques, such as U-Th dating method, the establishments of various hydroclimatic proxies, as well as the contributions to the reconstruction of the atmosphere14C variation history over the past ~54000 years. On the perspective of the future, the Chinese stalagmite community should continue to develop key techniques, further clarify the hydroclimatic significance of stalagmite proxies, impel the integration of related disciplines, and concentrate on key scientific issues in global climate change and major social demands. 展开更多
关键词 CAVE STALAGMITES Oxygen isotope Asian MONSOON WESTERLY Global climate change
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Great flood in the middle-lower Yellow River reaches at 4000 a BP inferred from accurately-dated stalagmite records 被引量:20
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作者 Liangcheng Tan Chuan-Chou Shen +2 位作者 Yanjun Cai hai cheng R.Lawrence Edwards 《Science Bulletin》 SCIE EI CSCD 2018年第4期206-208,共3页
Recently,Wu et al.[1]suggested an earthquake-induced landslide dam outburst flood on the eastern Tibetan Plateau at 1920BCE(3870 a BP,BP denotes year before 1950 CE)caused the Great Flood in the middle-lower Yellow Ri... Recently,Wu et al.[1]suggested an earthquake-induced landslide dam outburst flood on the eastern Tibetan Plateau at 1920BCE(3870 a BP,BP denotes year before 1950 CE)caused the Great Flood in the middle-lower Yellow River reaches,and resulted in the founding of Xia Dynasty at 3850 a BP.This age is$150–300younger than the previously estimated age of the Xia Dynasty[2].While the geological evidence of the outburst flood。 展开更多
关键词 石笋记录 活动范围 大洪水 BP 黄河 黄土高原 BCE 幻灯片
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Megadrought and cultural exchange along the proto-silk road 被引量:10
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作者 Liangcheng Tan Guanghui Dong +12 位作者 Zhisheng An RLawrence Edwards haiming Li Dong Li Robert Spengler Yanjun Cai hai cheng Jianghu Lan Rustam Orozbaev Ruiliang Liu Jianhui Chen hai Xu Fahu Chen 《Science Bulletin》 SCIE EI CSCD 2021年第6期603-611,M0004,共10页
Arid Central Asia(ACA), with its diverse landscapes of high mountains, oases, and deserts, hosted the central routes of the Silk Roads that linked trade centers from East Asia to the eastern Mediterranean.Ecological p... Arid Central Asia(ACA), with its diverse landscapes of high mountains, oases, and deserts, hosted the central routes of the Silk Roads that linked trade centers from East Asia to the eastern Mediterranean.Ecological pockets and ecoclines in ACA are largely determined by local precipitation. However, little research has gone into the effects of hydroclimatic changes on trans-Eurasian cultural exchange. Here,we reconstruct precipitation changes in ACA, covering the mid-late Holocene with a U-Th dated, ~3 a resolution, multi-proxy time series of replicated stalagmites from the southeastern Fergana Valley,Kyrgyzstan. Our data reveal a 640-a megadrought between 5820 and 5180 a BP, which likely impacted cultural development in ACA and impeded the expansion of cultural traits along oasis routes. Instead,it may have diverted the earliest transcontinental exchange along the Eurasian steppe during the 5 th millennium BP. With gradually increasing precipitation after the megadrought, settlement of peoples in the oases and river valleys may have facilitated the opening of the oasis routes, ‘‘prehistoric Silk Roads", of trans-Eurasian exchange. By the 4 th millennium BP, this process may have reshaped cultures across the two continents, laying the foundation for the organized Silk Roads. 展开更多
关键词 Megadrought Trans-Eurasian exchange Silk Roads Arid Central Asia MID-HOLOCENE
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Application of Avaatech X-ray fluorescence core-scanning in Sr/Ca analysis of speleothems 被引量:8
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作者 Dong LI Liangcheng TAN +9 位作者 Fei GUO Yanjun CAI Youbin SUN Gang XUE Xing cheng Hong YAN hai cheng R.Lawrence EDWARDS Yongli GAO Jessica KELLEY 《Science China Earth Sciences》 SCIE EI CAS CSCD 2019年第6期964-973,共10页
Application of X-ray fluorescence core-scanning(XRF-CS) on both marine and lake sediments has achieved remarkable results. However, its application has not been widely extended to the research on speleothems. In this ... Application of X-ray fluorescence core-scanning(XRF-CS) on both marine and lake sediments has achieved remarkable results. However, its application has not been widely extended to the research on speleothems. In this study, we measure the Sr abundance and the Sr/Ca ratios of three stalagmites(two aragonite stalagmites, one calcite stalagmite) using the state-of-the-art fourth-generation Avaatech high-resolution XRF core scanner. Through comparisons among different scan paths and among different scan resolutions, as well as comparisons with inductively coupled plasma optical emission spectrometer(ICP-OES), Itrax XRF, and Artax XRF results, we confirm that the Avaatech XRF core scanner could precisely, quickly, and nondestructively analyze the high-resolution Sr abundance of speleothems. Furthermore, we combine the stalagmite δ^(18)O records to explore the paleoclimatic significance of the measured stalagmite Sr/Ca. 展开更多
关键词 Avaatech XRF SPELEOTHEM Sr/Ca PALEOCLIMATE
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Earliest parietal art:hominin hand and foot traces from the middle Pleistocene of Tibet 被引量:9
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作者 David D.Zhang Matthew R.Bennett +15 位作者 hai cheng Leibin Wang haiwei Zhang Sally C.Reynolds Shengda Zhang Xiaoqing Wang Teng Li Tommy Urban Qing Pei Zhifeng Wu Pu Zhang Chunru Liu Yafeng Wang Cong Wang Dongju Zhang R.Lawrence Edwards 《Science Bulletin》 SCIE EI CSCD 2021年第24期2506-2515,M0004,共11页
At Quesang on the Tibetan Plateau we report a series of hand and foot impressions that appear to have been intentionally placed on the surface of a unit of soft travertine.The travertine was deposited by water from a ... At Quesang on the Tibetan Plateau we report a series of hand and foot impressions that appear to have been intentionally placed on the surface of a unit of soft travertine.The travertine was deposited by water from a hot spring which is now inactive and as the travertine lithified it preserved the traces.On the basis of the sizes of the hand and foot traces,we suggest that two track-makers were involved and were likely children.We interpret this event as a deliberate artistic act that created a work of parietal art.The travertine unit on which the traces were imprinted dates to between~169 and 226 ka BP.This would make the site the earliest currently known example of parietal art in the world and would also provide the earliest evidence discovered to date for hominins on the High Tibetan Plateau(above 4000 m a.s.l.).This remarkable discovery adds to the body of research that identifies children as some of the earliest artists within the genus Homo. 展开更多
关键词 TIBET Parietal art ICHNOLOGY HOMININ
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Orbital-scale Asian summer monsoon variations:Paradox and exploration 被引量:8
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作者 hai cheng haiwei ZHANG +11 位作者 Yanjun CAI Zhengguo SHI Liang YI chenglong DENG Qingzhen HAO Youbing PENG Ashish SINHA Hanying LI Jingyao ZHAO Ye TIAN Jonathan BAKER Carlos PEREZ-MEJIAS 《Science China Earth Sciences》 SCIE EI CSCD 2021年第4期529-544,共16页
The Asian summer monsoon(ASM) is a vast climate system, whose variability is critical to the livelihoods of billions of people across the Asian continent. During the past half-century, much progress has been made in u... The Asian summer monsoon(ASM) is a vast climate system, whose variability is critical to the livelihoods of billions of people across the Asian continent. During the past half-century, much progress has been made in understanding variations on a wide range of timescales, yet several significant issues remain unresolved. Of note are two long-standing problems concerning orbital-scale variations of the ASM.(1) Chinese loess magnetic susceptibility records show a persistent glacial-interglacial dominated ~100 kyr(thousand years) periodicity, while the cave oxygen-isotope(δ18 O) records reveal periodicity in an almost pure precession band(~20 kyr periodicity)—the "Chinese 100 kyr problem".(2) ASM records from the Arabian Sea and other oceans surrounding the Asian continent show a significant lag of 8–10 kyr to Northern Hemisphere summer insolation(NHSI), whereas the Asian cave δ18 O records follow NHSI without a significant lag—a discrepancy termed the "sea-land precession-phase paradox". How can we reconcile these differences? Recent and more refined model simulations now provide spatial patterns of rainfall and wind across the precession cycle, revealing distinct regional divergences in the ASM domain, which can well explain a large portion of the disparities between the loess, marine, and cave proxy records. Overall, we also find that the loess, marine, and cave records are indeed complementary rather than incompatible, with each record preferentially describing a certain aspect of ASM dynamics. Our study provides new insight into the understanding of different hydroclimatic proxies and largely reconciles the "Chinese 100 kyr problem" and "sea-land precession-phase paradox". 展开更多
关键词 ASM Orbital cycles Precession phase Different climatic proxies
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A multiple-proxy stalagmite record reveals historical deforestation in central Shandong, northern China 被引量:2
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作者 Liangcheng TAN Wen LIU +12 位作者 Tianli WANG Peng cheng Jingjie ZANG Xiqian WANG Le MA Dong LI Jianghu LAN R.Lawrence EDWARDS hai cheng hai XU Li AI Yongli GAO Yanjun CAI 《Science China Earth Sciences》 SCIE EI CAS CSCD 2020年第10期1622-1632,共11页
Evaluating anthropogenic impacts on regional vegetation changes during historical time is not only important for a better understanding of the Anthropocene but also valuable in improving the vegetation-climate models.... Evaluating anthropogenic impacts on regional vegetation changes during historical time is not only important for a better understanding of the Anthropocene but also valuable in improving the vegetation-climate models.In this study,we analyzed stable isotopes(δ^18O,δ^13C)and trace elements(Mg/Ca,Sr/Ca)of a stalagmite from Huangchao Cave in central Shandong,northern China.230Th and AMS14C dating results indicate the stalagmite deposited during 174BC and AD1810,with a hiatus between AD638 and 1102.Broad similarities of theδ^18O and trace elements in the stalagmite suggest they are reliable precipitation indexes.Theδ^13C of the stalagmite,a proxy of vegetation change,was generally consistent with local precipitation and temperature variations on a centennial-scale before the 15th century.It typically varied from–9.6‰to–6.3‰,indicating climate controlled C3 type vegetation during this period.However,a persistent and marked increasing trend in theδ^13C record was observed since the 15th century,resulting inδ^13C values from–7.7‰to–1.6‰in the next four centuries.This unprecedentedδ^13C change caused by vegetation deterioration cannot be explained by climate change but is fairly consistent with the dramatically increasing population and farmland in Shandong.We suggest that the increasing deforestation and reclamation in central Shandong began to affect vegetation in the mountain region of central Shandong since the 15th century and severely destroyed or even cleared the forest during the 16th–18th century. 展开更多
关键词 SPELEOTHEM Stable isotopes Trace elements DEFORESTATION Human activity 16th century
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Human activity and climate change triggered the expansion of rocky desertification in the karst areas of Southwestern China 被引量:1
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作者 Chaojun CHEN Daoxian YUAN +11 位作者 hai cheng Tsailuen YU Chuanchou SHEN RLawrence EDWARDS Yao WU Siya XIAO Jian ZHANG Tao WANG Ran HUANG Ziqi LIU Tingyong LI Junyun LI 《Science China Earth Sciences》 SCIE EI CSCD 2021年第10期1761-1773,共13页
It is conducive to the sustainable development of human beings in karst regions to research the mechanism of karst rocky desertification(KRD)expansion.Whether the large-scale KRD in southwestern China is caused by cli... It is conducive to the sustainable development of human beings in karst regions to research the mechanism of karst rocky desertification(KRD)expansion.Whether the large-scale KRD in southwestern China is caused by climate change or human activities is still controversial.In this study,the evolution of the KRD in southwestern China over the past 2000 years was reconstructed through the high-precisionδ^(13)C record of stalagmites from Shijiangjun(SJJ)Cave,Guizhou Province,China.Theδ^(13)C of the stalagmites from SJJ Cave exhibited heavy values from the Medieval Warm Period(MWP)to the Little Ice Age(LIA).Furthermore,theδ^(13)C records of other stalagmites and tufa from southwestern China also showed the same significant heavy trend.Because the stalagmiteδ^(13)C could record the change of ecological environment,it indicated that the consistent change of the stalagmitesδ^(13)C may record the process of KRD expansion in the karst regions of southwestern China.During the MWP,the stronger Asian summer monsoon and the northward movement of the rain belt led to a dry period in southwestern China and a wet period in northern China.In contrast,it was wet in southwestern China and dry in northern China during the LIA.In addition,after the Jing-Kang event(JK event,AD1127)occurred at the end of the Northern Song dynasty,the political and economic center of China migrated to southern China for the first time,which changed the population distribution pattern of larger population in the north and smaller population in the south.Therefore,the expansion of KRD in southwestern China was exacerbated in the MWP due to the change of climate in southwestern China,the migration of a large number of people,wars,the large-scale reclamation of arable land,and the cultivation of large areas of crops. 展开更多
关键词 Karst rocky desertification Jing-Kang event Stalagmiteδ13C record Medieval Warm Period Little Ice Age
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ENSO-Like Pacing of the Asian Summer Monsoon during the Early Holocene 被引量:1
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作者 Xiaohua SHAO Tao WANG +3 位作者 Yongjin WANG hai cheng Kan ZHAO Xinggong KONG 《Journal of Meteorological Research》 SCIE CSCD 2020年第2期325-335,共11页
We present a230Th-dated stalagmite oxygen isotope(δ^18O)record from Loushanguan Cave in the Yangtze River valley,China.The^δ18O record,if viewed as a proxy of the Asian summer monsoon(ASM)intensity,provides an ASM h... We present a230Th-dated stalagmite oxygen isotope(δ^18O)record from Loushanguan Cave in the Yangtze River valley,China.The^δ18O record,if viewed as a proxy of the Asian summer monsoon(ASM)intensity,provides an ASM history for the early Holocene with clear centennial-scale variability.A significant approximately 200-yr cycle between 10.2 and 9.1 ka BP(before present,where"present"is defined as the year AD 1950),as revealed by spectral power analyses,is of global significance and is probably forced by the Suess or de Vries cycle of solar activity.Here,we explore a physical mechanism to explain the relationship between the solar activity and the ASM.A strong coherence between the ASM and El Ni?o–Southern Oscillation(ENSO)has been observed by performing crosswavelet analyses on this cycle.Our study suggests that a strong(weak)ASM state corresponds to a warm(cold)ENSO,which is consistent with modern meteorological observations but contrasts with previous studies on regions far from the Meiyu rainbelt.We argue that the centennial fluctuations of the ASM are a fundamental characteristic forced by the solar activity,with the ENSO variability as a mediator.The relationship between ENSO and the ASM displayed spatial heterogeneity on the centennial scale during the early Holocene,which is a more direct analogue to the observed modern interannual variability of the ASM. 展开更多
关键词 isotope records Asian summer monsoon El Nino-Southern Oscillation centennial scale solar activity Yangtze River valley early Holocene
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Future Earth and Sustainable Developments 被引量:10
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作者 hai cheng 《The Innovation》 2020年第3期50-51,共2页
Our planet has been undergoing continuous warming since the industrial revolution(1850 CE),such that its mean temperature has risen-1C,and continues to rise to the present day.This is mainly due to human activity,par... Our planet has been undergoing continuous warming since the industrial revolution(1850 CE),such that its mean temperature has risen-1C,and continues to rise to the present day.This is mainly due to human activity,particularly CO_(2) emissions,resulting in far-reaching and mostly irreversible consequences to the Earth's systems.These include dominant negative changes in the atmosphere,hydrosphere,lithosphere,cryosphere,and biosphere.Since human influence has now overwhelmingly exceeded natural forces on a globe scale,some Earth scientists have proposed a geological epoch called the“Anthropocene”:a new epoch in the history of our planet,named after the significant influences of humanity on the globe.1 Indeed,our planet's climate is changing rapidly in the Anthropocene,and so climate change will become the defining challenge of our time,and its impacts will affect generations to come. 展开更多
关键词 EARTH EPOCH mostly
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Summer Monsoon Rainfall Variability in Central China over the Past 4700 Years and Its Possible Link to Solar Activity
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作者 Jingwei ZHANG Kan ZHAO +6 位作者 Xinggong KONG Yongjin WANG Xianfang WANG Shushuang LIU Zhenjun WANG hai cheng R.Lawrence EDWARDS 《Journal of Meteorological Research》 SCIE CSCD 2021年第4期594-606,共13页
Based on 467 pairs ofδ^(18)O andδ^(13)C records and 8230 Th dates from a stalagmite(BF4)from Xiniu Cave,central China,we present a reconstruction of 9-yr resolution monsoon rainfall record for the past 4700 years.Ou... Based on 467 pairs ofδ^(18)O andδ^(13)C records and 8230 Th dates from a stalagmite(BF4)from Xiniu Cave,central China,we present a reconstruction of 9-yr resolution monsoon rainfall record for the past 4700 years.Ourδ^(18)O record shows good coherence with East Asian summer monsoon(EASM)rainfall proxies from adjacent regions during the overlapping intervals,suggesting thatδ^(18)O signal in BF4 can be interpreted as a monsoon rainfall proxy.Theδ^(13) C variations are related to changes in local processes at the cave site,and regional rainfall and temperature changes.Based on theδ18 O record,a series of dry periods can be identified at 4500-4200,3500-3200,2800-2500,1900-1600,1400-1200,700-500,and 400-200 yr BP,while a series of wet periods can be identified at 4200-3600,2400-2200,3200-2800,1100-900,600-400,and 200-100 yr BP.Power spectrum analysis on ourδ^(18) O record reveals significant cycles at 470 and 80 yr,coinciding with the typical solar periodic variations.This result suggests that changes in solar activity play a dominant role in driving centennial-decadal monsoon rainfall variation in central China.Due to minor changes in solar irradiance(less than 1.5 W m^(-2))over the past 4700 years,our record was further compared to the El Nino-Southern Oscillation(ENSO)and Pacific Decadal Oscillation(PDO)proxies,confirming that solar forcing on monsoon rainfall changes might be amplified by the ENSO and PDO variations.From 600 to 150 yr BP(the Little Ice Age,LIA),a positive shift of 2‰can be revealed in both theδ^(18)O andδ^(13)C records,indicating a cold/dry climatic pattern.By comparing ourδ^(18)O andδ^(13)C records with historical documents,we suggest that the climatic deteriorations between 450 and 250 yr BP may have caused serious social unrest at the end of the Ming Dynasty. 展开更多
关键词 stalagmite record Xiniu Cave solar activity El Nino-Southern Oscillation(ENSO) Pacific Decadal Oscillation(PDO) amplify mechanism Little Ice Age(LIA)
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Ice-volume and insolation influences on hydroclimate changes in central eastern China during the antepenultimate glacial period
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作者 Quan WANG Shayue YUAN +10 位作者 Yijia LIANG Kan ZHAO Qingfeng SHAO Zhenqiu ZHANG Junji ZHU Xinggong KONG Yongjin WANG Jianghu LAN hai cheng chengwei XIA Yi LI 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第1期71-79,共9页
The rainfall changes in East Asian summer monsoon(EASM)regions on the orbital timescale remain controversial due to the lack of reliable rainfall records.Here,we present new multiproxy records(δ^(18)O,δ^(13)C,Sr/Ca ... The rainfall changes in East Asian summer monsoon(EASM)regions on the orbital timescale remain controversial due to the lack of reliable rainfall records.Here,we present new multiproxy records(δ^(18)O,δ^(13)C,Sr/Ca and Mg/Ca)of a230Thdated stalagmite from Hulu Cave in central eastern China.Multiproxy records reconstruct a regional hydroclimate history from 340 to 261 kyr BP(thousand years before present),approximately covering the antepenultimate glacial period.Theδ^(18)O record is dominated by the precessional cycles,suggesting that EASM responds to changes in Northern Hemisphere summer insolation(NHSI)on the orbital timescale.Significant correlations amongst theδ^(13)C,Sr/Ca and Mg/Ca suggest that a common factor,i.e.,the local hydrological cycle,controlled their variability,and their leading principal component can be used as a proxy linked to regional rainfall.This composite record bears a good similarity to those from the Chinese Loess Plateau,showing a gradually decreasing rainfall during the antepenultimate glacial period,consistent with changes in global ice volume.Superimposed on the long-term trend,three relative wetter intervals were responding to the higher NHSI periods,suggesting that EASM rainfall variability was induced by integrated effects of global ice volume and NHSI.The increased ice sheets and lower NHSI resulted in an increased meridional temperature gradient and southward shift of the westerlies,which shortened the duration of Meiyu and midsummer rainfall.The differences between the rainfall record and the stalagmiteδ^(18)O record indicate that the latter represents the overall EASM intensity linked to monsoon circulation,but does not directly reflect the rainfall changes at the cave sites. 展开更多
关键词 Hulu Cave Stalagmite records Antepenultimate glacial period East Asian summer monsoon rainfall
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Milankovitch theory and monsoon
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作者 hai cheng Hanying Li +13 位作者 Lijuan Sha Ashish Sinha Zhengguo Shi Qiuzhen Yin Zhengyao Lu Debo Zhao Yanjun Cai Yongyun Hu Qingzhen Hao Jun Tian Gayatri Kathayat Xiyu Dong Jingyao Zhao haiwei Zhang 《The Innovation》 2022年第6期77-91,共15页
The widely accepted“Milankovitch theory”explains insolation-induced waxing and waning of the ice sheets and their effect on the global climate on orbital timescales.In the past half century,however,the theory has of... The widely accepted“Milankovitch theory”explains insolation-induced waxing and waning of the ice sheets and their effect on the global climate on orbital timescales.In the past half century,however,the theory has often come under scrutiny,especially regarding its“100-ka problem.”Another drawback,but the one that has received less attention,is the“monsoon problem,”which pertains to the exclusion of monsoon dynamics in classic Milankovitch theory even though the monsoon prevails over the vast low-latitude(30N to30S)region that covers half of the Earth’s surface and receives the bulk of solar radiation.In this review,we discuss the major issues with the current form of Milankovitch theory and the progress made at the research forefront. 展开更多
关键词 MONSOON LATITUDE EARTH
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CAR-NK cell therapeutics for hematologic malignancies: hope is on the horizon
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作者 Kai-lin Xu hai cheng 《Blood Science》 2019年第2期156-160,共5页
Chimeric antigen receptor(CAR)-T-cell therapy has achieved significant success in the treatment of hematologic malignancies.However,treatment-related toxicity and side effects remain the major drawbacks.As an importan... Chimeric antigen receptor(CAR)-T-cell therapy has achieved significant success in the treatment of hematologic malignancies.However,treatment-related toxicity and side effects remain the major drawbacks.As an important effector cell in innate immunity,natural killer(NK)cells exert strong antitumor functions and have better application prospects in the immunotherapy of hematologic malignancies.Compared with T cells,NK cells exhibit several advantages such as MHC-independent recognition.CAR-modified NK(CAR-NK)cells may exhibit a better ability of killing tumor cells.Herein,we review mainly preclinical data related to the development of CAR-NK cells in treating blood cancers. 展开更多
关键词 HEMATOLOGY IMMUNOTHERAPY NK cells
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