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Heavy metal pollution in tidal zones of Bohai Bay using the dated sediment cores 被引量:11
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作者 QIN Yan-wen MENG Wei ZHENG Bing-hui SU Yi-bin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第3期610-615,共6页
Three sediment cores were collected in November 2003 from Dagu estuary to Qikou estuary. The main polluted heavy metals in the sediment of tidal zones for the Bohai Bay have been found by analyzing the relationship am... Three sediment cores were collected in November 2003 from Dagu estuary to Qikou estuary. The main polluted heavy metals in the sediment of tidal zones for the Bohai Bay have been found by analyzing the relationship among the contents of heavy metals, the contents of geochemical elements (Fe, AI and Mn) and the size of grain. The dominating contaminative elements in tidal sediments of Bohai Bay are Pb, Zn and Cd. Their contents are higher than the corresponding upper limit of environmental background values and they have very faint correlation with the corresponding contents of geochemical elements and the size of grain, indicating the anthropogenic enrichment. Especially, the preliminary study on the pollution sources and the history of heavy metals in the Dagu estuary has been done using the dated results. The contamination by Zn and Cd also started in the middle 1950s, while the contamination by Pb appeared in the early 1940s. The pollution by Zn and Cd mainly originate from sewage discharge, while the pollution by Pb has many sources, like atmosphere deposition and industrial discharRe. 展开更多
关键词 Bohai Bay tidal zone the dated sediment core heavy metal POLLUTION
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Acta Geologica Sinica (English Edition) Calls For Open-dated Submission of Paleontological Papers
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《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第6期1933-1933,共1页
Acta Geologica Sinica(English Edition) is indexed by SCI,with the impact factors ranging from 1.5 to 2.15,and also indexed by CA,the Bibliography and Index of Geology(BIG),Biological Abstracts,and Geographical Abs... Acta Geologica Sinica(English Edition) is indexed by SCI,with the impact factors ranging from 1.5 to 2.15,and also indexed by CA,the Bibliography and Index of Geology(BIG),Biological Abstracts,and Geographical Abstracts and many others.Internationally,Acta Geologica Sinica(English Edition)has been cooperated with Willey-BlackwellPublishing Corporation,and has all the papers published online.Acta Geologica Sinica(English Edition)has two submission websites at: http://mc.manuscriptcentral.com/ags for international authors and http://www.geojournals.cn/ dzxben/ch/index.aspx for Chinese authors. Authors can submit, inquire and download papers at either website. 展开更多
关键词 dated submission references submit http welcome encourage invite please editorial
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HOW THE CPC SEIZES MODERNITY The functionality of the Communist Party of China(CPC)is far from outdated and directly drives China’s embrace of tomorrow
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作者 Zheng Yongnian 《China Report ASEAN》 2021年第7期28-31,共4页
Former Chinese leader Deng Xiaoping was known as the chief architect of China’s reform and opening-up drive,and his inspection tour of southern China in 1992 ushered in a new chapter of history characterized by“thre... Former Chinese leader Deng Xiaoping was known as the chief architect of China’s reform and opening-up drive,and his inspection tour of southern China in 1992 ushered in a new chapter of history characterized by“three sustainables”:sustainable economic development,sustainable social stability,and sustainable institutional support and leadership.Fundamentally,the“three sustainables”deftly balanced relationships among economic,social,and political entities.Enterprises represent economic entities,the people are the social entity,and the CPC is the political entity.How exactly has the CPC promoted the modernity of China? 展开更多
关键词 CPC dated sustainable
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一个基于VFP的DateDiff函数的实现
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作者 梁里宁 《华南金融电脑》 2005年第10期76-77,共2页
在VFP的实际应用中,经常需要进行日期和时间间隔的计算,但与VB相比,VFP中只是提供了比较简单的计算。VFP和VB作为常用的可视化开发工具,都提供了丰富的数据类型和强大的内部函数。VB的内部函数DateDiff,能够根据不同参数的选择计算各种... 在VFP的实际应用中,经常需要进行日期和时间间隔的计算,但与VB相比,VFP中只是提供了比较简单的计算。VFP和VB作为常用的可视化开发工具,都提供了丰富的数据类型和强大的内部函数。VB的内部函数DateDiff,能够根据不同参数的选择计算各种常用的日期和时间间隔。本文介绍了VB中用于计算日期和时间间隔的DateDiff函数,并给出了在VFP中相关计算的实现。 展开更多
关键词 VB BFD DATE Diff VFP f函数 选择计算 时间间隔 内部函数 数据类型
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Shakespeare' s Sonnets Dated
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作者 W. Ron Hess 《Journal of Literature and Art Studies》 2015年第11期1003-1019,共17页
By using echoes in some sonnets to lines in certain plays, emphasizing those echoes which were not later repeated, and by applying dates to those plays, in 1926 Elizabeth Beckwith tentatively dated a third of the 154 ... By using echoes in some sonnets to lines in certain plays, emphasizing those echoes which were not later repeated, and by applying dates to those plays, in 1926 Elizabeth Beckwith tentatively dated a third of the 154 in the entire sonnets cycle. Her belief was that an unintentional authorial pattern of usage would be less subjective than other approaches to dating the sonnets. Yet, by use of dates from external allusions later applied by Prof. Leslie Hotson and other scholars, this author suggests that it may be possible to extend the total number of datable sonnets to over half of the cycle. However, Beckwith did not use dates for the plays which were later to become a standard dating scheme accepted by most scholars today, and so adjustments of her dates would change the dates she awarded to many of her selected sonnets. This author suggests that even the standard dating scheme is flawed, particularly if Shakespeare was dead when the Sonnets were published in 1609. He suggests another dating regime that meshes quite well with both Beckwith's 52 and an additional 27. Thus, the result for the 79 sonnets is to avoid certain problems in the distribution that Beckwith's method generated. The net result is what Beckwith termed "a skeleton around which the remaining sonnets can be safely built", but for over half rather than only a third of the cycle. This author suggests a half"skeleton" is more indicative of the chronology for the whole sonnets cycle than only a third. 展开更多
关键词 Shakespeare's Sonnets dating Shakespeare's works Shakespeare's1640 poems Elizabeth Beckwith
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Instructions for Authors of Chemical Research in Chinese Universities
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《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第10期I0001-I0001,共1页
The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and rev... The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and reviews written by faculty members,researchers and postgraduates in universities,colleges and research institutes all over China and overseas.It reports the latest and the most creative results of important fundamental research in all aspects of chemistry and of developments with significant consequences across sub-disciplines.This journal is sponsored by Jilin University and mandated by the Ministry of Education of P.R.China. 展开更多
关键词 JOURNAL consequences dated
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Instructions for Authors of Chemical Research in Chinese Universities
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《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第3期156-156,共1页
The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and rev... The journal Chemical Research in Chinese Universities is a comprehensive academic journal in the field of chemistry,published bimonthly since 1984.The journal publishes research articles,letters/communications and reviews written by faculty members,researchers and postgraduates in universities,colleges and research institutes all over China and overseas.It reports the latest and the most creative results of important fundamental research in all aspects of chemistry and of developments with significant consequences across sub-disciplines.This journal is sponsored by Jilin University and mandated by the Ministry of Education of P.R.China. 展开更多
关键词 JOURNAL consequences dated
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Neuroprotection by resveratrol-glucuronide and quercetin-glucuronide via binding to polyphenol-and glycosaminoglycan-binding sites in the laminin receptor
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作者 Rayudu Gopalakrishna Jennifer Aguilar +1 位作者 Emily Lee William J.Mack 《Neural Regeneration Research》 SCIE CAS 2025年第3期819-820,共2页
The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated ... The dietary polyphenolic compounds resveratrol and quercetin prevent neurodegenerative diseases in experimental models;however, they reach the brain only in nanomolar concentrations in the glucuronidated and sulfated forms, and not as the aglycone parent form(Pasinetti et al.,2015). 展开更多
关键词 RESVERATROL MOLAR dated
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GREEN TRANSITION,SUSTAINED GROWTH
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《China Today》 2024年第5期24-25,共2页
As people are becoming increasingly aware of the importance of environmental protection,the traditional energy-intensive and highly polluting industries are becoming outdated,needing to be upgraded or phased out,while... As people are becoming increasingly aware of the importance of environmental protection,the traditional energy-intensive and highly polluting industries are becoming outdated,needing to be upgraded or phased out,while low-carbon and clean industries are begining to mushroom.From new-energy vehicles to clean energy,from environmentally friendly building materials to the circular economy sector,the green industry has become a new economic growth pole. 展开更多
关键词 BECOMING dated CIRCULAR
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Geochronology and Geochemistry of Ore-related Granitoids in the Giant Gariatong Rb Deposit,Tibet and Implications for Rb Metallogeny in China 被引量:1
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作者 LIN Bin TANG Juxing +8 位作者 TANG Pan SUN Yan QI Jing MSANTOSH XIE Jinling DENG Shilin LI Faqiao XIE Fuwei ZHOU Aorigele 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期83-103,共21页
Rubidium(Rb)deposits mostly occur in the South China and Central Asia orogenic belts and are often closely associated with highly differentiated granites.This study investigates a newly-discovered giant Rb deposit at ... Rubidium(Rb)deposits mostly occur in the South China and Central Asia orogenic belts and are often closely associated with highly differentiated granites.This study investigates a newly-discovered giant Rb deposit at Gariatong in the Central Lhasa terrane in Tibet.Detailed field studies and logging data revealed that the Rb mineralization mainly occurs in monzogranite and is related to greisenization.LA-ICP-MS U-Pb dating of zircon yielded ages of 19.1±0.2 Ma and 19.0±0.2 Ma for greisenized monzogranite and fresh monzogranite,respectively.The monzogranites are characterized as strongly peraluminous,with high contents of SiO2,Al2O3,K2O and Na2O as well as a high differentiation index.They are enriched in light rare earth and large ion lithophile elements with significant negative Eu anomalies and depleted high fieldstrength elements.Petrological and geochemical features of these ore-related monzogranites suggest that they are highly fractionated S-type granites,derived from remelting of crustal materials in a post-collisional setting.The geochemistry of zircon and apatite points to a low oxygen fugacity of the ore-related monzogranite during the magma’s evolution.The discovery of the Gariatong Rb deposit suggests that the Central Lhasa terrane may be an important region for rare metal mineralization. 展开更多
关键词 LA-ICP-MS U-Pb dating GEOCHEMISTRY Rb metallogeny Gariatong TIBET
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Integrative biogeography: Validating hypotheses of species distribution 被引量:1
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作者 Zhong-E Hou Shu-Qiang Li 《Zoological Research(Diversity and Conservation)》 2024年第1期86-88,共3页
DEAR EDITOR,Biogeography is a scientific field dedicated to the investigation of the origins and distribution patterns of organisms,as well as predicting future alterations in their geographical distributions(Cox&... DEAR EDITOR,Biogeography is a scientific field dedicated to the investigation of the origins and distribution patterns of organisms,as well as predicting future alterations in their geographical distributions(Cox&Moore,2005).However,the majority of conclusions drawn within the field of biogeography are hypothetical.Rigorous testing of these biogeographic hypotheses remains a considerable challenge.This paper presents the concept of“integrative biogeography”,which emphasizes the experimental testing of biogeographic hypotheses through studies on geological history,as well as biotic and abiotic factors(Figure 1). 展开更多
关键词 BIOGEOGRAPHY DISTRIBUTION DATING
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Thermal and exhumation history of the Songnan Low Uplift,Qiongdongnan Basin:constraints from the apatite fission-track and zircon(U-Th)/He thermochronology
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作者 Xiaoyin Tang Kaixun Zhang +3 位作者 Shuchun Yang Shuai Guo Xinyan Zhao Zhizhao Bai 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期40-49,共10页
Significant advancements have been made in the study of Mesozoic granite buried hills in the Songnan Low Uplift(SNLU)of the Qiongdongnan Basin.These findings indicate that the bedrock buried hills in this basin hold g... Significant advancements have been made in the study of Mesozoic granite buried hills in the Songnan Low Uplift(SNLU)of the Qiongdongnan Basin.These findings indicate that the bedrock buried hills in this basin hold great potential for exploration.Borehole samples taken from the granite buried hills in the SNLU were analyzed using apatite fission track(AFT)and zircon(U-Th)/He data to unravel the thermal history of the basement rock.This information is crucial for understanding the processes of exhumation and alteration that occurred after its formation.Thermal modeling of a sample from the western bulge of the SNLU revealed a prolonged cooling event from the late Mesozoic to the Oligocene period(~80-23.8 Ma),followed by a heating stage from the Miocene epoch until the present(~23.8 Ma to present).In contrast,the sample from the eastern bulge experienced a more complex thermal history.It underwent two cooling stages during the late Mesozoic to late Eocene period(~80-36.4 Ma)and the late Oligocene period(~30-23.8 Ma),interspersed with two heating phases during the late Eocene to early Oligocene period(~36.4-30 Ma)and the Miocene epoch to recent times(~23.8-0 Ma),respectively.The differences in exhumation histories between the western and eastern bulges during the late Eocene to Oligocene period in the SNLU can likely be attributed to differences in fault activity.Unlike typical passive continental margin basins,the SNLU has experienced accelerated subsidence after the rifting phase,which began around 5.2 Ma ago.The possible mechanism for this abnormal post-rifting subsidence may be the decay or movement of the deep thermal source and the rapid cooling of the asthenosphere.Long-term and multi-episodic cooling and exhumation processes play a key role in the alteration of bedrock and contribute to the formation of reservoirs.On the other hand,rapid post-rifting subsidence(sedimentation)promotes the formation of cap rocks. 展开更多
关键词 granite buried hills (U-Th)/He dating fission-track dating EXHUMATION Songnan Low Uplift
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A tectono-thermal perspective on the petroleum generation,accumulation and preservation in the southern Ordos Basin, North China
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作者 Peng Yang Zhan-Li Ren +7 位作者 Jin-Hua Fu Hong-Ping Bao Hui Xiao Zheng Shi Kun Wang Yuan-Yuan Zhang Wen-Hui Liu Wen-Hou Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1459-1473,共15页
The southern Ordos Basin has excellent petroleum exploration prospects.However,the tectono-thermal history and the controls on petroleum generation,accumulation and preservation conditions in southern basin are unclea... The southern Ordos Basin has excellent petroleum exploration prospects.However,the tectono-thermal history and the controls on petroleum generation,accumulation and preservation conditions in southern basin are unclear.In this study,we analyzed the present geothermal field,paleo-geothermal gradient,maturity of the hydrocarbon source rocks,uplift and cooling process and tectono-thermal evolution history.In the study area,for the Ordovician,Permain and the Triassic strata,the present temperature is low(3070℃)in the southeastern area but high(80140℃)in the northwestern area.The paleogeothermal gradient varied from 24℃/km to 30℃/km with a heat flow of 58—69 m W/m^(2)(i.e.,a medium-temperature basin).The paleo-temperatures are higher than the present temperatures and the maximum paleo-temperatures controlled the thermal maturity of the source rocks.The vitrinite reflectance(Ro)values of the Triassic strata are>0.7%and the thermal maturity reached the middlemature oil generation stage.The Rovalues of the Permian-Ordovician strata are>1.8%and the thermal maturity reached the over-mature gas generation stage.The southern Ordos Basin has experienced the multiple tectonic events at the Late Ordovician Caledonian(452 Ma),Late Triassic(215 Ma),Late Jurassic(165160 Ma),End-Early Cretaceous(110100 Ma)and Cenozoic(since 40 Ma).A large-scale tectonothermal event occurred at the End-Early Cretaceous(110100 Ma),which was controlled by lithospheric extension,destruction and thinning.This event led to the highest paleo-temperatures and thermal maturities and coeval with the peak period of petroleum generation and accumulation.The southern Ordos Basin has undergone rapid and large-scale uplift since the Late Cretaceous due to expansion of the northeastern margin of the Tibetan Plateau,uplift of the Qinling orogenic belt and thrust faulting in the Liupanshan tectonic belt.The southern Ordos Basin experienced tectonic overprinting that was strong in the south and weak in the north.The strongest overprinting occurred in the southwestern part of the basin.The large-scale uplift,denudation and faulting led to oil and gas loss from reservoirs.The petroleum generation,accumulation and preservation in the southern Ordos Basin were affected by deep lithospheric structures and the tectono-thermal evolution.This work provides a novel tectono-thermal perspective on the petroleum generation,accumulation and preservation condition of the southern Ordos Basin. 展开更多
关键词 Fission-track dating Vitrinitereflectance Geothermal field Tectono-thermal evolution Petroleum geology Ordos Basin
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U-Pb dating of monazite in the Bainiuchang silver polymetallic deposit,Yunnan Province,and its limitation on Mesozoic mineralization
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作者 Bo-de Lu Wen-chang Li +10 位作者 Xue-long Liu Guang-zhi Meng Qi-he Long Hong Zhang Jun-shan Dao Fang-lan Li Jie-hu Zhou Mao-huang Fan Xue Mi Nan Shi Zhen-liang Cao 《China Geology》 CAS CSCD 2024年第3期592-595,共4页
1.Objective The Gejiu-Bozhushan-Laojunshan tin-tungsten polymetallic metallogenic belt is located in southeastern Yunnan.It is bounded by the Mile-Shizong Fault and the Yangzi Plate to the north and west,respectively,... 1.Objective The Gejiu-Bozhushan-Laojunshan tin-tungsten polymetallic metallogenic belt is located in southeastern Yunnan.It is bounded by the Mile-Shizong Fault and the Yangzi Plate to the north and west,respectively,while the Honghe Fault represents its southwestern boundary.It is adjacent to the Ailaoshan Fault,and extends to Guangxi and Vietnam to the southeast(Fig.1a;Liu JP et al.,2021). 展开更多
关键词 silver DATING SOUTHEAST
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Decoding complexity: the need to enhance precision and streamline spatial understanding in neuroscience
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作者 Sameehan Mahajani Armita Salahi +2 位作者 Brenda Gonzalez Charlotte Nelson Frank Hsiung 《Neural Regeneration Research》 SCIE CAS 2025年第3期801-802,共2页
Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides i... Neuroscience is the ultimate frontier in our quest for a comprehensive understanding of human behavior. Since its launch in 2009, the Human Connectome Project has emerged as a pioneering force, making heroic strides in elucidating the intricate correlation between structural information and the functioning of the human brain. 展开更多
关键词 behavior FRONTIER DATING
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Muscovite^(40)Ar/^(39)Ar isotopic dating of pegmatite veins in the Bieyesamas rare metal deposit in the Altay Mountain,Xinjiang,northwestern China
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作者 Geng-biao Qiao Ping Wang +1 位作者 Xiao-hong Wang Jun-lu Chen 《China Geology》 CAS CSCD 2024年第3期589-591,共3页
1.Objective The Altay Orogenic Belt in Xinjiang,China is located in the west of the Central Asian Orogenic Belt and in the transition zone between the Siberian Plate and the Kazakhstan-Junggar Plate,extending approxim... 1.Objective The Altay Orogenic Belt in Xinjiang,China is located in the west of the Central Asian Orogenic Belt and in the transition zone between the Siberian Plate and the Kazakhstan-Junggar Plate,extending approximately 500 km in northern Xinjiang,China(Fig.1a).The Altay Orogenic Belt has undergone two-way accretion of the Paleozoic crust and the Meso-Cenozoic intracontinental orogeny,leading to the formation of large numbers of intermediate-acid intrusions.More than 100000 pegmatite veins have been discovered in the intermediate-acid intrusions,and they constitute an important rare metal metallogenic belt of China(Fig.1b). 展开更多
关键词 XINJIANG dating isotopic
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Cassiterite U-Pb dating of the Yelonggou pegmatite-type lithium deposit in western Sichuan and its metallogenic age constraints
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作者 Xiang-yuan Yue Qian Zhang +4 位作者 Jun-jun Zhang Wei Zhang Jing Zhang Zhi-quan Jia Li-ping Luo 《China Geology》 CAS CSCD 2024年第1期153-156,共4页
1.Objective Pegmatite hosts important resource of rare metals,e.g.,lithium(Li)and beryllium(Be).In recent years,increasingly more studies were dedicated to characterize and unravel the formation of pegmatite-type depo... 1.Objective Pegmatite hosts important resource of rare metals,e.g.,lithium(Li)and beryllium(Be).In recent years,increasingly more studies were dedicated to characterize and unravel the formation of pegmatite-type deposits,for which accurate dating of pegmatite formation and mineralization is essential.The Songpan-Ganzi orogenic belt is a major rare metal metallogenic belt in China,hosting many important pegmatite-type Li deposits,including the Lijiagou,Dangba,Jiajika,Yelonggou,Cuola,and Declalongba.Radiometric age data(mica Ar-Ar and zircon/cassiterite U-Pb)from these Li deposits are sparse,ranging from 210 to 152 Ma.However,obtaining reliable zircon U-Pb dates can be a challenge due to the strong decidualization in pegmatites.As a result,the formation and mineralization ages of these rare metal pegmatites remain controversial,which hampers the development of pegmatite-type metallogenic model for the Songpan-Ganzi orogenic belt. 展开更多
关键词 DATING METALLOGENIC ZIRCON
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Mineral Chemistry,Trace Elements,Isotopic Analysis and Zircon U-Pb Dating in the Hesar Pluton,Northern UDMA,Iran:Implications for Pre-Collisional Magma Mixing
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作者 Kazem KAZEMI Soroush MODABBERI +3 位作者 Parisa GHARIBNEJAD XIAO Yilin Fatemeh SARJOUGHIAN Ali KANANIAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期657-678,共22页
The Hesar pluton in the northern Urumieh-Dokhtar magmatic arc hosts numerous mafic-microgranular enclaves(MMEs).Whole rock geochemistry,mineral chemistry,zircon U-Pb and Sr-Nd isotopes were measured.It is suggested th... The Hesar pluton in the northern Urumieh-Dokhtar magmatic arc hosts numerous mafic-microgranular enclaves(MMEs).Whole rock geochemistry,mineral chemistry,zircon U-Pb and Sr-Nd isotopes were measured.It is suggested that the rocks are metaluminous(A/CNK=1.32-1.45),subduction-related I-type calc-alkaline gabbro to diorite with similar mineral assemblages and geochemical signatures.The host rocks yielded an U-Pb crystallization age of 37.3±0.4 Ma for gabbro-diorite.MMEs have relatively low SiO_(2) contents(52.9-56.6 wt%)and high Mg^(#)(49.8-58.7),probably reflecting a mantle-derived origin.Chondrite-and mantle-normalized trace element patterns are characterized by LREE and LILE enrichment,HREE and HFSE depletion with slight negative Eu anomalies(Eu/Eu^(*)=0.86-1.03).The host rocks yield(^(87)Sr/^(86)Sr)_(i) ratios of 0.70492-0.70510,positive ε_(Nd)(t)values of+1.55-+2.06 and T_(DM2)of 707-736 Ma,which is consistent with the associated mafic microgranular enclaves((^(87)Sr/^(86)Sr)_(i)=0.705014,ε_(Nd)(t)=+1.75,T_(DM2)=729 Ma).All data suggest magma-mixing for enclave and host rock formation,showing a complete equilibration between mixed-mafic and felsic magmas,followed by rapid diffusion.The T_(DM1)(Nd)and T_(DM2)(Nd)model ages and U-Pb dating indicate that the host pluton was produced by partial melting of the lower continental crust and subsequent mixing with injected lithospheric mantlederived magmas in a pre-collisional setting of Arabian-Eurasian plates.Clinopyroxene composition indicates a crystallization temperature of~1000℃ and a depth of~9 km. 展开更多
关键词 ENCLAVE magma mixing zircon U-Pb dating Urumieh-Dokhtar magmatic arc
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Estimating Key Phenological Dates of Multiple Rice Accessions Using Unmanned Aerial Vehicle-Based Plant Height Dynamics for Breeding
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作者 HONG Weiyuan LI Ziqiu +5 位作者 FENG Xiangqian QIN Jinhua WANG Aidong JIN Shichao WANG Danying CHEN Song 《Rice science》 SCIE CSCD 2024年第5期617-628,I0066-I0070,共17页
Efficient and high-quality estimation of key phenological dates in rice is of great significance in breeding work. Plant height(PH) dynamics are valuable for estimating phenological dates. However, research on estimat... Efficient and high-quality estimation of key phenological dates in rice is of great significance in breeding work. Plant height(PH) dynamics are valuable for estimating phenological dates. However, research on estimating the key phenological dates of multiple rice accessions based on PH dynamics has been limited. In 2022, field traits were collected using unmanned aerial vehicle(UAV)-based images across 435 plots, including 364 rice varieties. PH, dates of initial heading(IH) and full heading(FH), and panicle initiation(PI), and growth period after transplanting(GPAT) were collected during the rice growth stage. PHs were extracted using a digital surface model(DSM) and fitted using Fourier and logistic models. Machine learning algorithms, including multiple linear regression, random forest(RF), support vector regression, least absolute shrinkage and selection operator, and elastic net regression, were employed to estimate phenological dates. Results indicated that the optimal percentile of the DSM for extracting rice PH was the 95th(R^(2) = 0.934, RMSE = 0.056 m). The Fourier model provided a better fit for PH dynamics compared with the logistic models. Additionally, curve features(CF) and GPAT were significantly associated with PI, IH, and FH. The combination of CF and GPAT outperformed the use of CF alone, with RF demonstrating the best performance among the algorithms. Specifically, the combination of CF extracted from the logistic models, GPAT, and RF yielded the best performance for estimating PI(R^(2) = 0.834, RMSE = 4.344 d), IH(R^(2) = 0.877, RMSE = 2.721 d), and FH(R^(2) = 0.883, RMSE = 2.694 d). Overall, UAV-based rice PH dynamics combined with machine learning effectively estimated the key phenological dates of multiple rice accessions, providing a novel approach for investigating key phenological dates in breeding work. 展开更多
关键词 phenological date plant height unmanned aerial vehicle machine learning rice breeding
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Editorial Commentary:The History of Controlling and Treating Infectious Diseases in Ancient China
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作者 Gui-sheng SONG 《Current Medical Science》 SCIE CAS 2024年第1期246-246,共1页
I recently read the article by LIU et all entitled The History of Controlling and Treating Infectious Diseases in Ancient China with great interest.The paper comprehensively summarizes ancient Chinese approaches to co... I recently read the article by LIU et all entitled The History of Controlling and Treating Infectious Diseases in Ancient China with great interest.The paper comprehensively summarizes ancient Chinese approaches to combat epidemics,elucidating them through the lens of three key elements of infectious diseases.Summarizing thousands of years of records detailing major infectious disease occurrences across various dynasties is no small feat. 展开更多
关键词 HISTORY ANCIENT DATING
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