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Ore Geology,H-O-C Isotopes and 40Ar-39Ar Dating of the Wutonggou Iron Deposit,Eastern tianshan,NW China:Implications for the Source,Timing,and Genesis of Hydrothermal Mineralization in a Sedimentary Iron Deposit

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Journal of Earth Science 2024年第4期35卷 1170-1185页

作者： Chun-Long wang Yi-tian wang State Key Laboratory of Geological Processes and Mineral Resources Collaborative Innovation Center for Exploration of Strategic Mineral ResourcesSchool of Earth ResourcesChina University of GeosciencesWuhan430074China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing100037China

The Wutonggou iron deposit is located in the well-known iron metallogenic belt in the eastern tianshan,NW China,and has been regarded as a sedimentary iron *** hydrothermal overprinting could play indispensable roles in the formation of high-grade iron ores in sedimentary iron deposits,previous studies mainly focused on sedimentary-related iron mineralization,while the nature and contribution of hydrothermal fluids are poorly ***,an integrated study of ore geology,H-O-C isotopes and^(40)Ar-^(39)Ar dating,is conducted on the Wutonggou deposit,in order to reveal the features,source,and timing of hydrothermal *** studied deposit includes two mining sections namely the Jianshan and ***δ^(18)O values of early magnetite from the Jianshan section range from+3.0‰to+5.8‰that nearly consistent with classic magmatic magnetite,while increase to 6.3‰-8.0‰in the late *** from the two sections shows comparable H-O isotopic compositions and identical fractionation trends,and is plotted in or periphery to the primary magmatic water *** from the two sections are broadly similar in carbon and oxygen isotopic compositions,and siderite from the Wutonggou section is plotted in the same ***,comparable stable isotopic compositions and evolution trends indicate similar magmatic fluids contributed hydrothermal iron mineralization in the two mining ***,water-rock interactions of varying degrees generated distinct mineralization styles in the Jianshan and Wutonggou sections,and caused the isotopic fractionation in late *** extracted from a hydrothermal siderite ore yielded a^(40)Ar-^(39)Ar plateau age of 299.5±2.0 Ma,indicates the timing of hydrothermal iron mineralization is corresponding to the emplacement of vicinity *** together,the hydrothermal mineralization in the Wutonggou iron deposit was the product of remobilization and upgrading of early sedimentary iron ores,a

关键词： iron deposits H-O-C isotopes 40Ar-39Ar dating sedimentary iron deposits Wutonggou iron deposit eastern tianshan

Intelligent reflecting surfaces-assisted millimeter wave communication:Channel estimation based on deep learning

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 49-56页

作者： Kang Xiaofei wang tian Liang Xian College of Communication and Information Engineering Xi'an University of Science and TechnologyXi'an 710600China

In response to the challenge posed by the complexity of the system and the difficulty in obtaining accurate channel state information(CSI)for millimeter wave communication assisted by intelligent reflecting surfaces(IRS),we propose a deep learning-based channel estimation *** proposed scheme employs a hybrid active/passive IRS architecture,wherein the least square(LS)algorithm is initially utilized to acquire the channel estimate from the active ***,this estimation is interpolated to obtain a preliminary channel estimation and ultimately refined into an accurate estimate of the channel using the channel super-resolution convolutional neural network(Chan-SRCNN)deep learning *** simulation results demonstrate that the proposed scheme surpasses LS,orthogonal matching pursuit(OMP),synchronous OMP(SOMP),and deep neural network(DNN)channel estimation algorithms in terms of normalized mean squared error(NMSE)performance,thereby validating the feasibility of the proposed approach.

关键词： intelligent reflecting surface millimeter wave channel estimation deep learning

Polyoxometalates coupled covalent organic frameworks as highly active photothermal nanoreactor for CO_(2)cycloaddition

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Nano Research 2024年第7期17卷 5975-5984页

作者： tian wang Yunqing Zhu Wei wang Junfeng Niu Zhiyi Lu Peilei He School of Environmental Science and Engineering Shaanxi University of Science and TechnologyXi’an 710021China Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China University of Chinese Academy of Sciences Beijing 100049China

Covalent organic frameworks(COFs)-based nanoreactors have attracted broad interest in many fields due to their voidconfinement ***,the inherent drawback of conventional nanoreactors is the lack of internal active sites,which limits their widespread ***,we report the construction of hierarchical COF(EB-TFP)nanoreactor with pre-synthesized polyoxometalates(POM,[PV_(2)W_(10)O_(40)]^(5–)(PV_(2)W_(10)))clusters encapsulated inside of COF(POM@COF).PV_(2)W_(10)@EB-TFP anchors nucleophilic-group(Br–ions)and PV_(2)W_(10)anion cluster within the COF framework via electrostatic interactions,which not only simplifies the reaction system but also enhances catalytic *** reaction performance of the PV_(2)W_(10)@EB-TFP nanoreactor can be tuned to achieve excellent catalytic activity in CO_(2)cycloaddition reaction(CCR)for~97.63%conversion and~100%selectivity under visible light irradiation.A mechanistic study based on density functional theory(DFT)calculations and insitu characterization was also carried *** summary,we have reported a method for achieving the uniform dispersion of POM single clusters into COF nanoreactor,demonstrating the potential of POM@COF nanoreactor for synergistic photothermal catalytic CO_(2)cycloaddition.

关键词： photothermal nanoreactor CO_(2)cycloaddition polyoxometalate photothermal-synergistic catalysis covalent organic frameworks

Review Article Li-current collector interface in lithium metal batteries

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Nano Research 2024年第10期17卷 8706-8728页

作者： tian-Yu wang Dingyi Zhao Keyue Liang Yuzhang Li Department of Chemical and Biomolecular Engineering University of CaliforniaLos AngelesLos AngelesCalifornia 90095USA

Interfaces within batteries,such as the widely studied solid electrolyte interface(SEI),profoundly influence battery *** these interfaces,the solid-solid interface between electrode materials and current collectors is crucial to battery performance but has received less discussion and *** review highlights the latest research advancements on the solid-solid interface between lithium metal(the next-generation anode)and current collectors(typically copper),focusing on factors affecting the Li-current collector interface and improvement strategies from perspectives of current collector substrate(lithiophilicity,crystal facets,mechanical properties,and topological structure),electrolyte chemistry,current density,stacking pressure,SEI,electric field and temperature,and provides a future directions and opportunities on this topic.

关键词： lithium metal anode current collectors Li-current collector interface solid-solid interface improvement strategies

Fracture geometry and breakdown pressure of radial borehole fracturing in multiple layers

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Petroleum Science 2024年第1期21卷 430-444页

作者： Yu-Ning Yong Zhao-Quan Guo Shou-Ceng tian Lu-Yao Ma tian-Yu wang Mao Sheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Beijing Petroleum Machinery Company Limited CNPC Engineering Technology R&D Company LimitedBeijing102206China Smart Energy Co. LtdChina Xiongan GroupXiong’an New Area071000HebeiChina

Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas *** paper aims to investigate fracture propagation and pressure characteristics of radial borehole fracturing in multiple layers.A series of laboratory experiments with artificial rock samples(395 mm×395 mm×395 mm)was conducted using a true triaxial fracturing *** crucial factors corresponding to the vertical distance of adjacent radial borehole layers(vertical distance),the azimuth and diameter of the radial borehole are *** results show that radial borehole fracturing in multiple layers generates diverse fracture *** types of fractures are identified based on the connectivity between hydraulic fractures and radial *** vertical distance significantly influences fracture propagation perpendicular to the radial borehole *** increase in the vertical distance impedes fracture connection across multiple radial borehole layers and reduces the fracture propagation distance along the radial borehole *** azimuth also influences fracture propagation along the radial borehole *** the azimuth reduces the guiding ability of radial boreholes,which makes the fracture quickly curve to the maximum horizontal stress *** breakdown pressure correlates with diverse fracture geometries *** the fractures connect multi-layer radial boreholes,increasing the vertical distance decreases the breakdown *** the azimuth and increasing the diameter also decrease the breakdown *** extrusion force exists between the adjacent fractures generated in radial boreholes in multiple rows,which plays a crucial role in enhancing the guiding ability of radial boreholes and results in higher breakdown *** research provides valuable theoretical insights for the field application of radial borehole fracturing technology in tight oil and g

关键词： Multi-layer radial boreholes Hydraulic fracturing Fracture propagation Pressure characteristic

An intelligent active probing and trace-back scheme for IoT anomaly detection

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Digital Communications and Networks 2024年第1期10卷 168-181页

作者： Luying wang Lingyi Chen Neal N.Xiong Anfeng Liu tian wang Mianxiong Dong School of Computer Science and Engineering Central South UniversityChangsha 410083China Department of Computer Science and Mathematics Sul Ross State UniversityAlpineTX 79830USA Artificial Intelligence and Future Networks Beijing Normal University&UICZhuhai 519087China Department of Information and Electronic Engineering Muroran Institute of TechnologyMuroran 050-8585Japan

Due to their simple hardware,sensor nodes in IoT are vulnerable to attack,leading to data routing blockages or malicious tampering,which significantly disrupts secure data *** Intelligent Active Probing and Trace-back Scheme for IoT Anomaly Detection(APTAD)is proposed to collect integrated IoT data by recruiting Mobile Edge Users(MEUs).(a)An intelligent unsupervised learning approach is used to identify anomalous data from the collected data by MEUs and help to identify anomalous nodes.(b)Recruit MEUs to trace back and propose a series of trust calculation methods to determine the trust of nodes.(c)The last,the number of active detection packets and detection paths are designed,so as to accurately identify the trust of nodes in IoT at the minimum cost of the network.A large number of experimental results show that the recruiting cost and average anomaly detection time are reduced by 6.5 times and 34.33%respectively,while the accuracy of trust identification is improved by 20%.

关键词： Anomaly detection Internet of things Integrating data collection Mobile edge users Intelligent

Understanding the Activity Performance of Comets 38P/Stephan-Oterma,64P/Swift-Gehrels and C/2017 M4(ATLAS)through Broadband Photometric Observations

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Research in Astronomy and Astrophysics 2024年第8期24卷 147-156页

作者： Xuan Zhang Jin-Zhong Liu Le-tian wang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

In this work,we report observations of three comets:38P/Stephan-Oterma,64P/Swift-Gehrels,and C/2017 M4(ATLAS),conducted with the Nanshan one-meter wide-field telescope in 2018 August and November,and *** extracted morphological features through image enhancement techniques and calculated the dust activity parameter,Afρ,along with dust mass loss rates and coma color indices using broadband photometric *** morphological analysis uncovered a spectrum of dust characteristics among the observed comets,ranging from a significant twisted structure in comet 38P/Stephan-Oterma’s coma to the regular coma envelope surrounding comet 64P/*** Afρvalues varied between 148.8±0.3 cm for 64P/Swift-Gehrels and1118.5±6.2 cm for C/2017 M4(ATLAS)(measured within a reference aperture radius ofρ=6″),indicating a range from moderate to high activity *** mass loss rates were estimated from 328.1 kg s^(-1)for comet 64P/Swift-Gehrels to 1395.5 kg s^(-1)for comet C/2017 M4(ATLAS).The color indices of comets 38P/Stephan-Oterma and C/2017 M4(ATLAS)closely resemble the average colors of active short-period comets and active longperiod comets,*** contrast,64P/Swift-Gehrels exhibits a significantly bluer hue than typical Jupiter family comets.

关键词： comets general-comets individual(38P/Stephan-Oterma,64P/Swift-Gehrels,C/2017 M4(ATLAS))-techniques photometric

Chemical derivatization strategies for enhancing the HPLC analytical performance of natural active triterpenoids

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Journal of Pharmaceutical Analysis 2024年第3期14卷 295-307页

作者： Xiao-Feng Huang Ying Xue Li Yong tian-tian wang Pei Luo Lin-Sen Qing Chengdu Institute of Biology Chinese Academy of SciencesChengdu610041China State Key Laboratory for Quality Research in Chinese Medicines Macao University of Science and TechnologyMacaoChina Sichuan Center for Disease Control and Prevention Chengdu610041China University of Chinese Academy of Sciences Beijing100049China

Triterpenoids widely exist in nature,displaying a variety of pharmacological *** triterpenoids in different matrices,especially in biological samples holds great ***-performance liquid chromatography(HPLC)has become the predominant method for triterpenoids analysis due to its exceptional analytical ***,due to the structural similarities among botanical samples,achieving effective separation of each triterpenoid proves challenging,necessitating significant improvements in analytical ***,triterpenoids are characterized by a lack of ultraviolet(UV)absorption groups and chromophores,along with low ionization efficiency in mass ***,routine HPLC analysis suffers from poor *** derivatization emerges as an indispensable technique in HPLC analysis to enhance its *** the structural characteristics of triterpenoids,various derivatization reagents such as acid chlorides,rhodamines,isocyanates,sulfonic esters,and amines have been employed for the derivatization analysis of *** review comprehensively summarized the research progress made in derivatization strategies for HPLC detection of ***,the limitations and challenges encountered in previous studies are discussed,and future research directions are proposed to develop more effective derivatization methods.

关键词： Triterpenoid HPLC Derivatization Quantification

CO_(2)flooding in shale oil reservoir with radial borehole fracturing for CO_(2)storage and enhanced oil recovery

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Petroleum Science 2024年第1期21卷 519-534页

作者： Jia-Cheng Dai tian-Yu wang Jin-Tao Weng Kang-Jian tian Li-Ying Zhu Gen-Sheng Li State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China China National Oil and Gas Exploration and Development Company Limited Beijing100034China

This study introduces a novel method integrating CO_(2)flooding with radial borehole fracturing for enhanced oil recovery and CO_(2)underground storage,a solution to the limited vertical stimulation reservoir volume in horizontal well fracturing.A numerical model is established to investigate the production rate,reservoir pressure field,and CO_(2)saturation distribution corresponding to changing time of CO_(2)flooding with radial borehole fracturing.A sensitivity analysis on the influence of CO_(2)injection location,layer spacing,pressure difference,borehole number,and hydraulic fractures on oil production and CO_(2)storage is *** CO_(2)flooding process is divided into four *** in layer spacing will significantly improve oil production rate and gas storage ***,serious gas channeling can occur when the spacing is lower than 20 *** the pressure difference between the producer and injector,the borehole number,the hydraulic fracture height,and the fracture width can also increase the oil production rate and gas storage *** analysis shows that layer spacing and fracture height greatly influence gas storage and oil *** outcomes are expected to provide a theoretical basis for the efficient development of shale oil reservoirs in the vertical direction.

关键词： Shale oil Radial borehole fracturing Embedded discrete fracture model Enhanced oil recovery Carbon storage