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Theoretical study of thiourea derivatives as chemosensors for fluoride and acetate anions

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Science China Chemistry 2012年第7期55卷 1428-1434页

作者： JIN RuiFa sun weidong College of Chemistry and Chemical Engineering Chifeng UniversityChifeng 024000China

The different interactions between a chemosensor,1-(naphthalen-2-yl)-3-(6-nitrobenzothiazol-2-yl)-thiourea(1),and F-,acetate(AcO-),Cl-,and Br-anions have been investigated theoretically at the B3LYP/6-31+G(d,p) level with the basis set superposition error(BSSE) *** was found that the high selectivity of compound 1 for F-can be ascribed to the ability of the anion to deprotonate the N-H fragment of the host sensor,while the chemosensor also has a strong affinity for AcO-by virtue of the formation of a hydrogen-bonded *** charge transfer(ICT) causes the colorimetric signaling of compound 1 after interaction with F-/AcO-.A study of substituent effects suggested that the O/NH-and O/S-substituted derivatives are also expected to be promising candidates for chromogenic F-/AcO-chemosensors.

关键词：化学传感器硫脲衍生物阴离子醋酸分子内电荷转移取代基效应取代衍生物相互作用

Neoproterozoic Diamictite of the Luoquan Formation from the North China Block and Their Implications

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Journal of Earth Science 2023年第4期34卷 1128-1139页

作者： Peishan Sui weidong sun Nan Han Lei Wang Shiwen Xie Zihang Huang Xiaohong Wang Hongmei Gong Jin Liu Jinyan Lin Yuanyuan Xiao CAS Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Center of Deep-Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China Changqing Oilfield Exploration and Development Research Institute Xi'an 710018China Yanchang Oilfield Exploration and Development Technology Research Center Xi'an 716001China Beijing SHRIMP Center Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Public Technology Service Center Institute of OceanologyChinese Academy of SciencesQingdao 266071China Department of Geology Northwest UniversityXi'an 710069China

Glacial diamictite may provide important information on paleoenvironment and average composition of the upper continental crust(UCC).In this study,we report sedimentary facies,petrological and geochemical characteristics of Neoproterozoic diamictite from a profile of the Luoquan Formation on the southern margin of the North China Block(NCB).Upwards the sampling profile,lithostratigraphic strata vary from massive diamictite with poorly sorted carbonate gravels to laminated diamictite with small gravels of terrestrial detrital *** the profile,CaO-MgO-LOI-Sr values decrease with the increase of SiO_(2)-Al2O_(3)-K2O *** these petrological and geochemical variations indicate a change from lodgement till deposition in the proximal of ice sheet to ice-rafting deposition in glacial-marine environment with less dolomite to supply their *** with previous studies on diamictite from other outcrops on the NCB,the deposition of Luoquan diamictite reflects that the glaciation on the NCB vanished and the ice-rafting effect weakened with glacial transgression *** addition,significant co-variations of various elements with La and Al2O_(3)confirm the significant conservation of most analyzed elements during the sedimentary processes to produce diamictite.

关键词： diamictite North China Craton paleoenvironment the Luoquan Formation Neopro-terozoic sedimentation.

Experimental constraints on trace element partitioning between coesite and hydrous silicate melt at 5 GPa and 1500-1750℃

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Science China Earth Sciences 2021年第7期64卷 1171-1183页

作者： Wei YAN Xi LIU Saijun sun weidong sun Dan WU Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education of ChinaBeijing 100871China School of Earth and Space Sciences Peking UniversityBeijing 100871China Center of Deep Sea Research Institute of OceanographyChinese Academy of SciencesQingdao 266071China Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

Trace element partitioning between coesite and hydrous silicate melt has been investigated at 5 GPa and 1500-1750℃.High-P experiments successfully produced large coesite crystals in equilibrium with large silicate melt pools(plus kyanite and corundum crystals in some cases).Scanning electron microscopy and micro-Raman spectroscopy were employed to characterize the phases and the ***-dispersive electron microprobe analyses were performed to quantify conventional major elements,and laser ablation-inductively coupled plasma-mass spectrometry analyses were successfully conducted to quantify trace ***,high-P partition coefficients were obtained for 33 *** general coesite is a very pure *** a few possible exceptions like Sc,Ti,and V,nearly all other trace elements are incompatible in ***,the partitioning behaviors of nearly all trace elements except some 4+cations cannot be readily described by the lattice strain model,presumably implying a minor role for the cation size in the trace-element *** our experimental results with the results in the literature,some T and P effects on the element partitioning behavior have been observed:T seemingly has different effects on different trace elements,but P might negatively correlate with the partition coefficients in all *** to its large modal fraction in some subducted materials such as the continental crustal material,coesite might play an important role in the distributions of some trace elements,Ti for example.

关键词： Partition coefficients High-P experiments LA-ICP-MS Coesite Hydrous silicate melt Temperature and pressure dependence

Feverfew: a scalable coverage-based hybrid overlay for Internet-scale pub/sub networks

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Science China(Information Sciences) 2014年第5期57卷 51-64页

作者： MA XingKong WANG YiJie sun weidong National Key Laboratory for Parallel and Distributed Processing School of ComputerNational University of Defense Technology

The publish/subscribe(pub/sub)paradigm is a popular communication model for data dissemination in large-scale distributed ***,scalability comes with a contradiction between the delivery latency and the memory *** one hand,constructing a separate overly per topic guarantees real-time dissemination,while the number of node degrees rapidly increases with the number of *** the other hand,maintaining a bounded number of connections per node guarantees small memory cost,while each message has to traverse a large number of uninterested nodes before reaching the *** this paper,we propose Feverfew,a coverage-based hybrid overlay that disseminates messages to all subscribers without uninterested nodes involved in,and increases the average number of node connections slowly with an increase in the number of subscribers and *** major novelty of Feverfew lies in its heuristic coverage mechanism implemented by combining a gossip-based sampling protocol with a probabilistic searching *** on the practical workload,our experimental results show that Feverfew significantly outperforms existing coverage-based overlay and DHT-based overlay in various dynamic network environments.

关键词： publish/subscribe coverage-based data dissemination topic-based gossip

High oxygen fugacity magma:implication for the destruction of the North China Craton

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Acta Geochimica 2020年第2期39卷 161-171页

作者： Zhekun Zhang Mingxing Ling Lipeng Zhang Saijun sun weidong sun CAS Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China State Key Laboratory of Isotope Geochemistry.Guangzhou Institute of Geochemistry Chinese Academy of Sciences.Guangzhou 510640China Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100094China

The mechanism of lithospheric removal and destruction of the North China Craton(NCC)has been hotly debated for *** is now generally accepted that the subduction of the(Paleo)-Pacific plate played an important role in this ***,how the plate subduction contributed to the craton destruction remains *** we report high oxygen fugacity(fO2)characteristics of the Yunmengshan granite,e.g.,hematitemagnetite intergrowth supported by zircon Ce^4+/Ce^3+ratios and apatite Mn oxygen fugacity *** fO2 magmas are widely discovered in Late Mesozoic(160-130 Ma)adakitic rocks in central *** origin of high fO2 magma is likely related to the input of the"oxidized mantle components",which shows a dose connection between plate subduction and destruction of the *** research area is^1500 km away from the current Pacific subduction *** the back-arc extension of Japan Sea since the Cretaceous,this distance may be shortened to^800 km,which is still too far for normal plate *** subduction is the best candidate that was responsible for the large scale magmatism and the destruction of the *** slab-derived fluids and/or melts were liberated into an overlying mantle wedge and modified the lithospheric *** of the subducting plate induced the large-scale upwelling of asthenospheric mantle and triggered the formation of extensive high fO2 intraplate magmas.

关键词： High oxygen fugacity Decratonization North China Craton Plate subduction

Calcium isotopic signatures of depleted mid-ocean ridge basalts from the northeastern Pacific

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Journal of Oceanology and Limnology 2020年第5期38卷 1476-1487页

作者： ZHU Hongli DU Long ZHANG Zhaofeng sun weidong Center of Deep Sea Research Institute of OceanographyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China

A number of high-temperature processes(e.g.,melt-rock reactions,metasomatism,partial melting)can produce signifi cant Ca isotopic fractionation and heterogeneity in the mantle,but the mechanism for such fractionation remains *** investigate the eff ect of mantle partial melting on Ca isotopic fractionation,we reported high-precision Ca isotopic compositions of depleted mid-ocean ridge basalts(MORBs)from the East Pacifi c Rise and Ecuador Rift in the northeastern Pacifi ***δ44/40 Ca of these MORB samples exhibit a narrow variation from 0.84‰to 0.88‰with an average of 0.85‰±0.03‰,which are similar to those of reported MORBs(0.83‰±0.11‰)and back-arc basin basalts(BABBs,0.80‰±0.08‰)in literature,but are lower than the estimate value for the bulk silicate Earth(BSE,0.94‰±0.05‰).The lowδ44/40 Ca signatures of MORB samples in this study cannot be caused by fractional crystallization,since intermediate-mafi c diff erentiation has been demonstrated having only limited eff ects on Ca isotopic ***,the off set ofδ44/40 Ca between MORBs and the BSE is most likely produced by mantle partial *** this process,the light Ca isotopes are preferentially transferred to the melt,while the heavy ones tend to stay in the residue,which is consistent with the fact thatδ44/40 Ca of melt-depleted peridotites increases with partial melting in *** behavior of Ca isotopes during mantle partial melting is closely related to the inter-mineral(Cpx and Opx)Ca isotopic fractionation and melting mineral *** partial melting is one of the common processes that can induce lowerδ44/40 Ca values in basalts and Ca isotopic heterogeneity in Earth’s mantle.

关键词： Ca isotopes mid-ocean ridge basalts(MORBs) mantle partial melting magma diff erentiation

Plate convergence in the Indo-Pacific region

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Journal of Oceanology and Limnology 2020年第4期38卷 1008-1017页

作者： sun weidong ZHANG Lipeng LIAO Renqiang sun Saijun LI Congying LIU He Center of Deep Sea Research Institute of OceanologyCenter for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

The Indo-Pacific convergence region is the best target to solve the teo remaining challenges of the plate tectonics theory,i.e.,subduction initiation and the driving force of plate *** studies proposed that the Izu-Bonin subduction initiation belongs to spontaneous initiation,which implies that it started from extension,followed by low angle *** geodynamic modeling suggests that the initiation of plate subduction likely occurred along a transform fault,which put the young spreading ridge in direct contact with old oceanic ***,however,does not explain the simultaneous subduction initiation in the west Pacific region in the ***,the subduction initiations in the Izu-BoninMariana,the Aleutian,and the Tonga-Kermadec trenches are associated with oceanic crusts of different ages,yet they occurred at roughly the same time,suggesting that they were all triggered by a maj or change in the Pacific ***,low angle subduction induces compression rather than extension,which requires external compression *** that the famous Hawaiian-Emperor bending occurred roughly at the same time with the onset of westward subductions in the west Pacific,we propose that these Cenozoic subductions were initiated by the steering of the Pacific plate,which are classified as induced *** subduction initiation usually occurs in young ocean basins,forming single-track *** closure s of Neo-Tethys Oceans were likely triggered by plume s in the south,forming northward ***,the Indian plate kept on moving northward more than 50 Ma after the collision between the Indian and Eurasian continents and the break-off of the subducted oceanic slab attached to *** strongly suggests that slab pull is not the main driving force of plate tectonics,whereas slab sliding is.

关键词： plate tectonics subduction initiation drifting history Pacific plate Indian plate slab sliding

锂的圈层循环与资源富集过程:从高原盐湖到造山带伟晶岩

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岩石学报 2024年第2期40卷 591-604页

作者：陈晨闫庆贺章荣清李庆宽姜禾禾刘海洋秦占杰张西营孙卫东中国科学院海洋研究所深海研究中心青岛266071 中国地质大学地质过程与矿产资源国家重点实验室北京100083 云南大学地球科学学院昆明650500 南京大学地球科学与工程学院内生金属矿床成矿机制研究国家重点实验室南京210023 中国科学院青海盐湖研究所青海省盐湖地质与环境重点实验室西宁810008 中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029

盐湖卤水型锂矿与富锂伟晶岩是目前最为主要的可利用锂资源,前者是经地表风化/高温水岩淋滤形成的水体通过蒸发作用浓缩而成的卤水,而后者被认为是陆表风化沉积物熔融产物经高演化形成的富锂硬岩。大陆地壳是此类表生物质循环最根本的物... 详细信息

盐湖卤水型锂矿与富锂伟晶岩是目前最为主要的可利用锂资源,前者是经地表风化/高温水岩淋滤形成的水体通过蒸发作用浓缩而成的卤水,而后者被认为是陆表风化沉积物熔融产物经高演化形成的富锂硬岩。大陆地壳是此类表生物质循环最根本的物源,因而探究富锂地壳的形成及其表生风化剥蚀对于理解盐湖与伟晶岩锂成矿至关重要。本文将从元素循环视角切入,结合内生高温-外生低温过程中锂的元素地球化学行为,梳理锂在俯冲带各圈层的循环过程,探讨富锂地壳的形成机制及其对高原盐湖与造山带伟晶岩锂资源发育的影响。研究发现:(1)俯冲板片对弧岩浆锂的物质贡献有限;(2)厚地壳环境下的弧岩浆具有更高的锂含量;(3)造山带富锂弧岩石的循环应是盐湖与伟晶岩锂成矿的重要控制因素。

关键词：锂循环盐湖 LCT伟晶岩造山地壳加厚大陆风化

Plate subduction, oxygen fugacity, and mineralization

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Journal of Oceanology and Limnology 2020年第1期38卷 64-74页

作者： LIU He LIAO Renqiang ZHANG Lipeng LI Congying sun weidong Key Laboratory of Marine Geology and Environment Center of Deep-Sea ResearchInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Laboratory for Marine Biology and BiotechnologyPilot National Laboratory for Marine Science and TechnologyQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Plate subduction is the largest natural factory that processes elements,which controls recycling and mineralization of a variety of *** are three major ore deposit belts in the world:the circumPacific,the centralAsian,and the Tethys *** the three belts are closely associated with plate subductions,the mechanism remains *** approached this problem from systematic studies on the behaviours of elements during geologic *** contribution summaries the recent progress of our research *** results suggest that porphyry Cu deposits form through partial melting of subducted young oceanic crust under oxygen fugacities higher than AFMQ^+1.5,which is promoted after the elevation of atmospheric oxygen at ca.550 *** deposits are associated with reducing magmatic rocks formed as a consequence of slab *** Neo-Tethys tectonic regime hosts more than 60%of the world's total Sn *** is due to the reducing environment formed during the subduction of organic rich *** the same reason,porphyry Cu deposits formed in the late stages during the closure of the Neo-Tethys *** deposits are also controlled by slab rollback,but is not so sensitive to oxygen *** related W/Sn deposits are mostly accompanied by abundant accessory fluorites due to the breakdown of phengite and *** of phengite is also significant for hard rock lithium deposits,whereas orogenic belt resulted from plate subduction promote the formation of Li brine *** red bed basins near the Nanling region are favorable for Li *** Mo and Re are enriched in the oxidationreduction cycle during surface processes,and may get further enriched once Mo-,Re-enriched sediments are subducted and involved in *** plate subduction,Mo and Re fractionate from each *** is mainly hosted in porphyry Mo deposits and to a less extent,porphyry Cu-Mo deposits,whereas Re is predominantly hosted in

关键词： plate subduction oxygen fugacity ore deposits geochemical behaviors subduction factory