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Age and petrogenesis of late Mesozoic intrusions in the Huoluotai porphyry Cu-(Mo)deposit,northeast China:Implications for regional tectonic evolution

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Geoscience Frontiers 2022年第2期13卷 311-332页

作者： Yong-gang sun Bi-le Li Zhong-hai Zhao feng-yue sun Qing-feng Ding Xu-sheng Chen Jie-biao Li Ye Qian Yu-jin Li College of Earth Sciences Jilin UniversityChangchun 130061China College of Mining Liaoning Technical UniversityFuxin 123000China Qiqihaer Institute of Geological Exploration Heilongjiang 161006China School of Environment Harbin Institute of TechnologyHarbin 150090China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Land and ResourcesChangchun 130061China

Multi-stage igneous rocks developed in the recently discovered Huoluotai Cu-(Mo)deposit provide new insights into the controversial late Mesozoic geodynamic evolution of the northern segment of the Great Xing’an Range(NSGXR).Zircon U-Pb dating suggests that the monzogranite,ore-bearing granodiorite porphyry,diorite porphyry,and granite porphyry in the deposit were emplaced at 179.5±1.6,148.9±0.9,146.1±1.3,and 142.2±1.5 Ma,respectively.The Re-Os dating of molybdenite yielded an isochron age of 146.9±2.3 Ma(MSWD=0.27).The Jurassic adakitic monzogranite and granodiorite porphyry are characterized by high SiO_(2)and Na_(2)O contents,low K_(2)O/Na_(2)O ratios,low Mg O,Cr,and Ni contents,low zirconεHf(t)values relative to depleted mantle,and relatively high Th contents.They were produced by partial melting of a subducted oceanic slab,with involvement of marine sediments in the magma source and limited interaction with mantle peridotites during magma ascent.The Late Jurassic diorite porphyry is characterized by moderate SiO_(2) contents,high Mg O,Cr,and Ni contents,and positive dominatedεHf(t)values,indicating it was produced by partial melting of a subduction-modified lithospheric mantle wedge and underwent limited crustal contamination during magma ascent.The early Early Cretaceous adakitic granite porphyry shows high SiO_(2) and K_(2)O contents and K_(2)O/Na_(2)O ratios,low Mg O,Cr,and Ni contents,enriched Sr-Nd isotopic compositions,and slightly positive zirconεHf(t)values,suggesting it was produced by partial melting of thickened mafic lower crust.The NSGXR experienced a tectonic history that involved flat-slab subduction(200-160 Ma),and tearing and collapse(150-145 Ma)of the Mongol-Okhotsk oceanic lithosphere.The period of magmatic quiescence from ca.160 to 150 Ma was a response to flat-slab subduction of the Mongol-Okhotsk oceanic lithosphere.Crustal thickening in the NSGXR(145-133 Ma)was due to the collision between the Amuria Block and the Siberian Craton.

关键词： Geochemistry Zircon U-Pb dating Huoluotai Cu-(Mo)deposit Flat-slab subduction Mongol-Okhotsk Ocean

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Metallogenesis and ore-forming time of the Changtuxili Mn-Ag-Pb-Zn deposit in Inner Mongolia:Evidence from C-O-S isotopes and U-Pb geochronology

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Geoscience Frontiers 2020年第4期11卷 1369-1380页

作者： Kuo Zhang Ruo-Shi Jin feng-yue sun Bi-Le Li Peng He yue-Long Zhang Shuo Guo Tian-Fu Zhang College of Earth Sciences Jilin UniversityChangchun130061China Tianjin Center China Geological SurveyTianjin300170China North China Center for Geoscience Innovation Tianjin300170China Qiqihar Branch Heilongjiang Institute of Geological Survey and ResearchQiqihar150036China

This paper reports new geochronological(U-Pb) and isotope(C,O,and S) data to investigate the timing of mineralization and mode of ore genesis for the recently discovered Changtuxili Mn-Ag-Pb-Zn deposit,located on the western slopes of the southern Great Hinggan Range in NE China.The mineralization is hosted by intermediate-acidic lavas and pyroclastic rocks of the Baiyingaolao Formation.Three stages of mineralization are identified:quartz-pyrite(Stage I),galena-sphalerite-tetrahedrite-rhodochrosite(Stage II),and quartz-pyrite(Stage Ⅲ).δ13C and δ18O values for carbonate from the ore vary from-8.51‰ to-4.96‰ and 3.97‰ to 15.90‰,respectively,which are indicative of a low-temperature alteration environment.δ34SV-CDT values of sulfides range from-1.77‰ to 4.16‰ and show a trend of equilibrium fractionation(δ34SPy>δ34SSp>δ34SGn).These features indicate that pyrite,sphalerite,and galena precipitated during the period of mineralization.The alteration mineral assemblage and isotope data indicate that the weakly acidic to weakly alkaline ore-forming fluid was derived largely from meteoric water and the ore-forming elements C and S originated from magma.During the mineralization,a geochemical barrier was formed by changes in the pH of the ore-forming fluid,leading to the precipitation of rhodochrosite.On the basis of the mineralization characteristics,new isotope data,and comparison with adjacent deposits,we propose that the Changtuxili Mn-Ag-Pb-Zn deposit is an intermediate-to lowsulfidation epithermal deposit whose formation was controlled by fractures and variability in the pH of the oreforming fluid.The surrounding volcanic rocks yield zircon U-Pb ages of 160-146 Ma(Late Jurassic),indicating that the mineralization is younger than 146 Ma.

关键词： Inner Mongolia Changtuxili Mn-Ag-Pb-Zn deposit C-O-S isotope geochemistry Zircon U-Pb age Intermediate-to low-sulfidation epithermal deposit

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Smart Gait:A Gait Optimization Framework for Hexapod Robots

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 146-159页

作者： Yunpeng Yin feng Gao Qiao sun yue Zhao Yuguang Xiao State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Lenovo Corporation ShanghaiChina AI Institute School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The current gait planning for legged robots is mostly based on human presets,which cannot match the flexible characteristics of natural mammals.This paper proposes a gait optimization framework for hexapod robots called Smart Gait.Smart Gait contains three modules:swing leg trajectory optimization,gait period&duty optimization,and gait sequence optimization.The full dynamics of a single leg,and the centroid dynamics of the overall robot are considered in the respective modules.The Smart Gait not only helps the robot to decrease the energy consumption when in locomotion,mostly,it enables the hexapod robot to determine its gait pattern transitions based on its current state,instead of repeating the formalistic clock-set step cycles.Our Smart Gait framework allows the hexapod robot to behave nimbly as a living animal when in 3D movements for the first time.The Smart Gait framework combines offline and online optimizations without any fussy data-driven training procedures,and it can run efficiently on board in real-time after deployment.Various experiments are carried out on the hexapod robot LittleStrong.The results show that the energy consumption is reduced by 15.9%when in locomotion.Adaptive gait patterns can be generated spontaneously both in regular and challenge environments,and when facing external interferences.

关键词： Gait optimization Swing trajectory optimization Legged robot Hexapod robot

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Dissociation of gas hydrates by hydrocarbon migration and accumulation-derived slope failures:An example from the South China Sea

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Geoscience Frontiers 2022年第2期13卷 295-310页

作者： Zhi-feng Wan Wei Zhang Chong Ma Jin-Qiang Liang Ang Li Da-Jiang Meng Wei Huang Cheng-Zhi Yang Jin-feng Zhang yue-feng sun School of Marine Sciences Sun Yat-sen UniversityZhuhai 519082China Gas Hydrate Engineering Technology Center Guangzhou Marine Geological SurveyChina Geological SurveyMinistry of Natural ResourcesGuangzhou 510075China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China School of Mathematics and Physics China University of Geosciences(Wuhan)Wuhan 430074China Qingdao Institute of Marine Geology Qingdao 266071China Department of Geology&Geophysics Texas A&M UniversityCollege Station 77843-3115United States

The mechanism of slope failure associated with overpressure that is caused by hydrocarbon migration and accumulation remains unclear.High-resolution seismic data and gas hydrate drilling data collected from the Shenhu gas hydrate field(site SH5)offer a valuable opportunity to study the relations between submarine slope failure and hydrocarbon accumulation and flow that is associated with a~2 kmdiameter gas chimney developed beneath site SH5 where none gas hydrates had been recovered by drilling and sampling despite the presence of distinct bottom simulating reflectors(BSRs)and favorable gas hydrate indication.The mechanism of submarine slope failure resulted from buoyancy extrusion and seepage-derived deformation which were caused by overpressure from a~1100 m-high gas column in a gas chimney was studied via numerical simulation.The~9.55 MPa overpressure caused by hydrocarbons that migrated through the gas chimney and then accumulated beneath subsurface gas hydratebearing impermeable sediments.This may have resulted in a submarine slope failure,which disequilibrated the gas hydrate-bearing zone and completely decomposed the gas hydrate once precipitated at site SH5.Before the gas hydrate decomposition,the largely impermeable sediments overlying the gas chimney may have undergone a major upward deformation due to the buoyancy extrusion of the overpressure in the gas chimney,and slope failure was initiated from plastic strain of the sediments and reduced internal strength.Slope failure subsequently resulted in partial gas hydrate decomposition and sediment permeability increase.The pressurized gas in the gas chimney may have diffused into the overlying sediments controlled by seepage-derived deformation,causing an effective stress reduction at the base of the sediments and significant plastic deformation.This may have formed a new cycle of submarine slope failure and finally the total gas hydrate dissociation.The modeling results of buoyancy extrusion and seepage-derived deformation of the overpressure in the gas c

关键词： Natural gas hydrate Submarine slope failure Gas chimney Buoyancy extrusion Seepage-derived deformation Shenhu area Northern South China Sea

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Characteristics and triggering mechanisms of early negative Indian Ocean Dipole

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Acta Oceanologica Sinica 2024年第3期43卷 59-65页

作者： yue Fang Shuangwen sun Yongcan Zu Jianhu Wang Lin feng First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Qingdao Marine Science and Technology CenterQingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in China.Early nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in summer than La Niña-related nIOD.However,the characteristics and triggering mechanisms of early nIOD are unclear.Our results based on reanalysis datasets indicate that the early nIOD and La Niña-related nIOD are the two major types of nIOD,and the former accounts for over one third of all the nIOD events in the past six decades.These two types of nIODs are similar in their intensities,but are different in their spatial patterns and seasonal cycles.The early nIOD,which develops in spring and peaks in summer,is one season earlier than the La Niña-related nIOD.The spatial pattern of the wind anomaly associated with early nIOD exhibits a winter monsoon-like pattern,with strong westerly anomalies in the equatorial Indian Ocean and eastly anomalies in the northern Indian Ocean.Opposite to the triggering mechanism of early positve IOD,the early nIOD is induced by delayed Indian summer monsoon onset.The results of this study are helpful for improving the prediction skill of IOD and its climate impacts.

关键词： Indian Ocean Dipole(IOD) triggering mechanism Indian summer monsoon seasonal cycle negative IOD

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The Spatiotemporal Distribution Characteristics of Cloud Types and Phases in the Arctic Based on CloudSat and CALIPSO Cloud Classification Products

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Advances in Atmospheric Sciences 2024年第2期41卷 310-324页

作者： yue sun Huiling YANG Hui XIAO Liang feng Wei CHENG Libo ZHOU Weixi SHU Jingzhe sun Key Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) and Department of Lower Atmospheric Observation Research(LAOR)Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth Sciences University of Chinese Academy of Sciences(UCAS)Beijing 100049China Beijing Institute of Applied Meteorology Beijing 100029China

The cloud type product 2B-CLDCLASS-LIDAR based on CloudSat and CALIPSO from June 2006 to May 2017 is used to examine the temporal and spatial distribution characteristics and interannual variability of eight cloud types(high cloud, altostratus, altocumulus, stratus, stratocumulus, cumulus, nimbostratus, and deep convection) and three phases(ice,mixed, and water) in the Arctic. Possible reasons for the observed interannual variability are also discussed. The main conclusions are as follows:(1) More water clouds occur on the Atlantic side, and more ice clouds occur over continents.(2)The average spatial and seasonal distributions of cloud types show three patterns: high clouds and most cumuliform clouds are concentrated in low-latitude locations and peak in summer;altostratus and nimbostratus are concentrated over and around continents and are less abundant in summer;stratocumulus and stratus are concentrated near the inner Arctic and peak during spring and autumn.(3) Regional averaged interannual frequencies of ice clouds and altostratus clouds significantly decrease, while those of water clouds, altocumulus, and cumulus clouds increase significantly.(4) Significant features of the linear trends of cloud frequencies are mainly located over ocean areas.(5) The monthly water cloud frequency anomalies are positively correlated with air temperature in most of the troposphere, while those for ice clouds are negatively correlated.(6) The decrease in altostratus clouds is associated with the weakening of the Arctic front due to Arctic warming, while increased water vapor transport into the Arctic and higher atmospheric instability lead to more cumulus and altocumulus clouds.

关键词： CloudSat and CALIPSO cloud type cloud phase temporal and spatial distribution interannual variation

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AP-1 and SP1 trans-activate the expression of hepatic CYP1A1 and CYP2A6 in the bioactivation of AFB1 in chicken

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Science China(Life Sciences) 2024年第7期67卷 1468-1478页

作者： Jiang Deng Jia-Cheng Yang yue feng Ze-Jing Xu Kamil Kuča Meng Liu Lv-Hui sun State Key Laboratory of Agricultural Microbiology Hubei Hongshan LaboratoryFrontiers Science Center for Animal Breeding and Sustainable ProductionCollege of Animal Sciences and TechnologyHuazhong Agricultural UniversityWuhan 430070China Department of Chemistry Faculty of ScienceUniversity of Hradec KraloveHradec Kralove 50003Czech Republic

Dietary exposure to aflatoxin B1(AFB1)is harmful to the health and performance of domestic animals.The hepatic cytochrome P450s(CYPs),CYP1A1 and CYP2A6,are the primary enzymes responsible for the bioactivation of AFB1to the highly toxic exo-AFB1-8,9-epoxide(AFBO)in chicks.However,the transcriptional regulation mechanism of these CYP genes in the liver of chicks in AFB1metabolism remains unknown.Dual-luciferase reporter assay,bioinformatics and site-directed mutation results indicated that specificity protein 1(SP1)and activator protein-1(AP-1)motifs were located in the core region-1,063/-948,-606/-541 of the CYP1A1 promoter as well as-636/-595,-503/-462,-147/-1 of the CYP2A6 promoter.Furthermore,overexpression and decoy oligodeoxynucleotide technologies demonstrated that SP1 and AP-1 were pivotal transcriptional activators regulating the promoter activity of CYP1A1 and CYP2A6.Moreover,bioactivation of AFB1to AFBO could be increased by upregulation of CYP1A1 and CYP2A6 expression,which was trans-activated owing to the upregulation of AP-1,rather than SP1,stimulated by AFB1-induced reactive oxygen species.Additionally,nano-selenium could reduce ROS,downregulate AP-1 expression and then decrease the expression of CYP1A1 and CYP2A6,thus alleviating the toxicity of AFB1.In conclusion,AP-1 and SP1 played important roles in the transactivation of CYP1A1 and CYP2A6 expression and further bioactivated AFB1to AFBO in chicken liver,which could provide novel targets for the remediation of aflatoxicosis in chicks.

关键词： aflatoxin B1 CYP1A1 CYP2A6 SP1 AP-1 transcriptional activation

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Turbulence Statistics of Thermo-Buoyancy Supercritical Fuel Flow in a Regenerative Cooling Channel

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Journal of Thermal Science 2024年第1期33卷 126-137页

作者： sun feng XIE Gongnan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Department of Thermal Engineering Tsinghua UniversityBeijing 100084China

Active regenerative cooling with supercritical hydrocarbon fuel is considered as the most promising thermal protection method.The existence of buoyancy force would lead to strongly anisotropic flow and thermal transport characteristics.It is closely related to the cooling performance of the engine.To elucidate the mechanisms of turbulent transport,the large eddy simulation(LES) was performed to assess turbulence statistics within different turbulence scales.The results indicated that the buoyancy and inertial force together dominated the change of turbulent structure.Moreover,the spatial thermal buoyancy effect significantly suppressed the vertical velocity fluctuation.This is due to the laminar motion caused by the buoyancy force,thereby weakening the thermal transport.For the statistics of velocity fluctuation,it was found that the buoyancy force and inertial force greatly weaken the vertical and streamwise velocity fluctuation,respectively.For the statistics of thermal transport,the results pointed out that the near-wall heat transport characteristics need to be paid more attention.The thickness of the temperature mixing boundary layer led to the attenuation of vertical heat flux,which inhibited vertical temperature diffusion and predisposed to extreme conditions of heat transfer deterioration.The results can enhance the academic understanding of the heat transfer mechanism of supercritical fluids,and give guidance for further applications of thermal protection.

关键词： active regenerative cooling large eddy simulation(LES) buoyancy force turbulence statistics

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Natural marmatite photocatalyst for treatment of mineral processing wastewater to help zero wastewater discharge

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Journal of Environmental Sciences 2024年第8期142卷 83-91页

作者： Meirong Wu Wei sun Xiangsong Meng Jianhua Kang yue Yang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

Mineral processing wastewater(MPW)with large discharge and high toxicity affects environmental safety,and the realizing zero discharge of MPW is of great significance for reducing environmental pollution,saving water resources,and promoting the sustainable development of the mining industry.In this study,we reported natural marmatite(NM)as a low-cost and efficient photocatalyst for the treatment of MPW to help zero wastewater discharge.The photocatalytic activity of NM was evaluated by the removal of total organic carbon(TOC)from MPW under visible-light illumination,and the optimal degradation conditions were discussed.Results showed that superoxide free radicals(^(·)O_(2)^(-))were the dominant active species responsible for organic pollutants degradation,and 74.25%TOC removal was obtained after 120 min reaction under the optimum treatment conditions.Meanwhile,the wastewater treated by NM photocatalysis can be reused in the flotation system without adverse impact on the product index.Based on these findings,a model of zero wastewater discharge for flotation with the help of photocatalytic treatment was established,it indicated that the water of the whole system can be balanced without affecting the ore dressing index,which showed that visible light-driven photocatalyst has a promising application prospect in the treatment and recycling of industrial wastewater.

关键词： Natural mineral Photocatalysis Industrial wastewater Wastewater recycling Water balance

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On the global smooth solutions of 3D incompressible Hall-MHD equations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 319-327页

作者： yue Gao-cheng sun Wen-da School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106China

The present paper is devoted to the well-posedness issue for the 3D incompressible Hall-MHD system obtained from kinetic models. Our analysis strongly relies on the use of the Fourier analysis. We establish the global existence of smooth solutions for a class of large initial data, this result implies the initial velocity and magnetic field can be arbitrarily large.

关键词： 3D Hall-MHD well-posedness Fourier analysis

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