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First SHRIMP zircon U-Pb dating constraints for the Ediacaran Wenghui Biota

Journal of Earth Science 2024年

作者： Mingsheng Zhao Feng Tang Giovanni Mussini Yulan Li heng zhang Jianshu chen Linzhi Gao Department of Earth Sciences University of Cambridge State Key Laboratory of Palaeobiology and Stratigraphy (Nanjing Institute of Geology and Palaeontology CAS) 111 Geological Brigade Guizhou Bureau of Geology and Mineral Resources College of Paleontology Shenyang Normal University Institute of Geology Chinese Academy of Geological Sciences Guizhou Geological Survey

The Ediacaran period records a significant turning point in the evolution of life on Earth， witnessing the rise to ecological dominance of macroscopic tissue-grade organisms. The Wenghui biota from the Doushantuo Formation of South China hosts abundant multicellular algal macrofossils and problematica， some of which might be closely related to taxa from classic late Ediacaran assemblages from South Australia and the White Sea biota of Russia. However， a lack of well-resolved isotopic age estimates has hampered efforts to constrain the timing of appearance of the Wenghui biota， obfuscating its significance to our understanding of Ediacaran macroevolution in the aftermath of the Snowball Earth events. Here， we present the first SHRIMP zircon U-Pb dating results for samples obtained from a laminated tuff ash layer at the base of the Wenghui biota in the Doushantuo Formation， Jiangkou County， Tongren City， Guizhou Province， China. Our analyses yield an age of 595.4 ± 5.3 Ma for the first appearance of Wenghui biota， suggesting that its appearance postdated that of the Lantian- and Weng’an biotas， but preceded that of the Miaohe biota. These newly obtained age proxies offer an independent test of previous isotopic estimates for the age of the Wenghui biota， providing new chronostratigraphic evidence to map the succession of Ediacaran fossil assemblages on the Yangtze Platform during the Doushantuo interval. These data suggest that the Lantian， Weng’an， Wenghui， and Miaohe biotas may record a sequence of biotic assemblages attesting to successive phases in the radiation of Ediacaran macroscopic organisms， particularly macroalgae.

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Optimal Planning of Hybrid AC/DC Low-voltage Distribution Networks Considering DC Conversion of Three-phase Four-wire Low-voltage AC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 141-153页

作者： Bo zhang Lu zhang Wei Tang Gen Li chen Wang the College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China the Electric Energy Group Department of Engineering TechnologyTechnical University of Denmark(DTU)2750 BallerupDenmark the Power Distribution Technology Center State Grid Beijing Electric Power Research InstituteBeijing 100075China

The increasing integration of distributed household photovoltaics(PVs)and electric vehicles(EVs)may further ag gravate voltage violations and unbalance of low-voltage distribu tion networks(LVDNs).DC distribution networks can increase the accommodation of PVs and EVs and mitigate mutilple pow er quality problems by the flexible power regulation capability of voltage source *** paper proposes schemes to es tablish hybrid AC/DC LVDNs considering the conversion of the existing three-phase four-wire low-voltage AC systems to DC op *** characteristics and DC conversion constraints of typical LVDNs are *** addition,converter configura tions for typical LVDNs are proposed based on the three-phase four-wire characteristics and quantitative analysis of various DC ***,an optimal planning method of hybrid AC/DC LVDNs is proposed,which is modeled as a bi-level programming model considering the annual investments and three-phase *** are conducted to verify the effectiveness of the proposed optimal planning *** ulation results show that the proposed optimal planning method can increase the integration of PVs while simultaneously reduc ing issues related to voltage violation and unbalance.

关键词： Optimal planning low-voltage distribution net work three-phase unbalance DC conversion

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An ionic liquid-assisted strategy for enhanced anticorrosion of low-energy PEO coatings on magnesium-lithium alloy

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JOURNAL OF MAGNESIUM AND ALLOYS 2024年第6期12卷 2380-2396页

作者： zhang, You chen, Chuping Tian, Haoyue Wang, Shuqi Wen, chen chen, Fei Beijing Inst Petrochem Technol Coll New Mat & Chem Engn Hydrogen Energy Res Ctr Beijing 102617 Peoples R China Harbin Inst Technol Key Lab Adv Struct Funct Integrated Mat & Green Mf Harbin 150001 Peoples R China China Acad Space Technol Beijing Spacecrafts Beijing 100190 Peoples R China

A low-energy plasma electrolytic oxidation (LePEO) technique is developed to simultaneously improve energy efficiency and anti-corrosion. Ionic liquids (1-butyl-3-methylimidazole tetrafluoroborate (BmimBF 4 )) as sustainable corrosion inhibitors are chosen to investigate the corrosion inhibition behavior of ionic liquid (ILs) during the LePEO process for LA91 magnesium-lithium (Mg-Li) alloy. Results show that the ionic liquid BmimBF 4 participates in the LePEO coating formation process, causing an increment in coating thickness and surface roughness. The low conductivity of the ionic liquid is responsible for the voltage and breakdown voltage increases during the LePEO with IL process (LePEO-IL). After adding BmimBF 4 , corrosion current density decreases from 1.159 x 10 - 4 A cm - 2 to 8.143 x 10 - 6 A cm - 2 . The impedance modulus increases to 1.048 x 10 4 Q cm - 2 and neutral salt spray remains intact for 24 h. The superior corrosion resistance of the LePEO coating assisted by ionic liquid could be mainly attributed to its compact and thick barrier layer and physical absorption of ionic liquid. The ionic liquid-assisted LePEO technique provides a promising approach to reducing energy consumption and improving film performance. (c) 2023 Chongqing University. Publishing services provided by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license ( http://***/licenses/by-nc-nd/4.0/ ) Peer review under responsibility of Chongqing University

关键词： Magnesium-lithium alloy Plasma electrolytic oxidation Low energy Ionic liquid Corrosion resistance. CORROSION-RESISTANCE OXIDATION COATINGS MICROARC OXIDATION COPPER CORROSION INHIBITION PHOSPHATE MICROSTRUCTURE DERIVATIVES SILICATE

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MOF-derived Cu embedded into N-doped mesoporous carbon as a robust support of PdAu nanocatalysts for ethanol electrooxidation

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Rare Metals 2024年第3期43卷 1083-1094页

作者： Yu-Fu Huang Peng Wu Jun-Ping Tang Jian Yang Jing Li Shuai chen Xue-Ling Zhao Chengchen Bin-Wei zhang Yan-Yun Ma Wei-heng Shi Dong-Hai Lin Shi-Gang Sun School of Energy and Materials Shanghai Engineering Research Center of Advanced Thermal Functional MaterialsShanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai201209China State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China School of Chemistry and Chemical Engineering Chongqing UniversityChongqing401331China Center of Advanced Energy Technology and Electrochemistry Institute of Advanced Interdisciplinary StudiesChongqing UniversityChongqing400044China Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou215123China Department of Materials Science and Engineering Drexel UniversityPhiladelphiaPA19104USA

Metal-organic frameworks(MOFs)h ave attracted widespread attention due to their large surface area and porous *** designing the nanostructures of MOFs to promote their application in ethanol electrooxidation is still a ***,a novel Cu-NCNs(Cu-nitrogen-doped carbon nanotubes)support was synthesized by pyrolysis of melamine(MEL)and Cu-ZIF-8 together,and then,Pd-Au nanoalloys were loaded by sodium borohydride reduction method to prepare PdAu@Cu-NCNs *** generating mesoporous carbon with high specific surface area and favorable electron and mass transport can be used as a potential excellent carrier for PdAu *** addition,the balance of catalyst composition and surface structure was tuned by controlling the content of Pd and ***,the best-performed Pd_(2)Au_(2)@Cu-NCN-1000-2(where 1000 means the carrier calcination temperature,and 2 means the calcination constant temperature time)catalyst exhibits better long-term stability and electrochemical activity for ethanol oxidation in alkaline media(4.80 A·mg^(-1)),which is 5.05 times higher than that of commercial Pd/C(0.95 A·mg^(-1)).Therefore,this work is beneficial to further promoting the application of MOFs in direct ethanol fuel cells(DEFCs)and can be used as inspiration for the design of more efficient catalyst support structures.

关键词： Metal-organic frameworks(MOFs) N-doped Mesoporous carbon PdAu Ethanol electrooxidation

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Real-time,single-particle chemical composition,volatility and mixing state measurements of urban aerosol particles in southwest China

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Journal of Environmental Sciences 2024年第2期136卷 361-371页

作者： Luyao chen Junke zhang Jiaqi Li Xiaojuan Huang Yuzheng Xiang Jing chen Tingru Pan Wei zhang Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China Sichuan Environmental Monitoring Center Chengdu 610074China

To investigate the volatility of atmospheric particulates and the evolution of other particulate properties(chemical composition,particle size distribution and mixing state)with temperature,a thermodenuder coupled with a single particle aerosol mass spectrometer was used to conduct continuous observations of atmospheric fine particles in Chengdu,southwest *** of their complex sources and secondary reaction processes,the average mass spectra of single particles contained a variety of chemical components(including organic,inorganic and metal species).When the temperature rose from room temperature to280℃,the relative areas of volatile and semi-volatile components decreased,while the relative areas of less or non-volatile components ***(>80%)nitrate and sulfate existed in the form of NH_(4)NO_(3)and(NH_(4))_(2)SO_(4),and their volatilization temperatures were50–100℃and 150–280℃,*** contribution of biomass burning(BB)and vehicle emission(VE)particles increased significantly at 280℃,which emphasized the important role of regional biomass burning and local motor vehicle emissions to the core of *** the increase in temperature,the particle size of the particles coated with volatile or semi-volatile components was reduced,and their mixing with secondary inorganic components was significantly *** formation of K-nitrate(KNO_(3))and K-sulfate(KSO_(4))particles was dominated by liquid-phase processes and photochemical reactions,*** KNO_(3)and BB particles is the key to improving *** new results are helpful towards better understanding the initial sources,pollution formation mechanisms and climatic effects of fine particulate matter in this megacity in southwest China.

关键词： Atmospheric fine particles TD-SPAMS Chemical composition Volatility Mixing state

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Ru(II)-Catalyzed ortho C-H Allylation of N-Aryl-7-azaindoles with 2-Methylidene Cyclic Carbonate

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Chinese Journal of Chemistry 2024年第9期42卷 985-989页

作者： Jing zhang Quan-Jian Luo Han-Chi Wang Jin-heng Li Bo Sun State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and Technology QingdaoShandong266042China State key Laboratory of Applied Organic Chemistry Lanzhou University LanzhouGansu 7300ooChina School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

A Ru(II)-catalyzed ortho allylation reaction of N-aryl-7-azaindole with readily available 2-methylidene cyclic carbonate has been *** reaction is an effective pathway for synthesizing 7-azaindole derivatives with a wide scope of substrates and high *** addition,the method can be extended to the allylation of other heterocyclic compounds and several cyclic carbonates,highlighting the practicality of this strategy for synthesis.

关键词： Ru(II) Allylation N-Aryl-7-azaindoles Cyclic carbonates Heterocyclic compounds C-H activation

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Variable Stars in the 50BiN Open Cluster Survey.Ⅲ.NGC 884

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Research in Astronomy and Astrophysics 2024年第2期24卷 36-45页

作者： Lin-Hong Wang Qian-heng Nie Kun Wang Xiao-Dian chen Chun-Guang zhang Li-Cai Deng Xiao-Bin zhang Tian-Lu chen Department of Physics College of ScienceTibet UniversityLhasa 850000China Key Laboratory of Cosmic Rays Tibet UniversityMinistry of EducationLhasa 850000China Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Middlesex School ConcordMassachusettsUnited States of America School of Physics and Astronomy China West Normal UniversityNanchong 637002China

Open clusters are the basic building blocks that serve as a laboratory for the study of young stellar populations in the Milky *** stars in open clusters provide a unique way to accurately probe the internal structure,temporal and dynamical evolutionary stages of individual stars and the host *** most powerful tool for such studies is time-domain photometric *** paper follows the route of our previous work,concentrating on a photometric search for variable stars in NGC *** target cluster is the companion of NGC869,forming the well-known double cluster system that is gravitationally *** the observation run in 2016 November,a total of 9247 B-band CCD images and 8218Ⅴ-band CCD images were *** detected a total of 15 stars with variability in visual brightness,including five Be stars,three eclipsing binaries,and seven of unknown *** new variable stars were discovered in this *** also compared the variable star content of NGC 884 with its companion NGC 869.

关键词： stars variables general-(Galaxy:)open clusters and associations individual(…,…)-(stars:)binaries general

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Calculation of Mass Concrete Temperature Containing Cooling Water Pipe Based on Substructure and Iteration Algorithm

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工程与科学中的计算机建模(英文) 2024年第1期138卷 813-826页

作者： heng zhang Chao Su Zhizhong Song Zhenzhong Shen Huiguang Lei Changjiang Institute of Survey PlanningDesign and ResearchWuhan430010China College ofWater Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Chief Engineer Office Wujiang Company of Goupitan Power Construction CooperationYuqing564408China

Mathematical physics equations are often utilized to describe physical phenomena in various fields of science and *** such equation is the Fourier equation,which is a commonly used and effective method for evaluating the effectiveness of temperature control measures for mass *** important measure for temperature control in mass concrete is the use of cooling water ***,the mismatch of grids between large-scale concrete models and small-scale cooling pipe models can result in a significant waste of calculation time when using the finite element ***,the temperature of the water in the cooling pipe needs to be iteratively calculated during the thermal transfer *** substructure method can effectively solve this problem,and it has been validated by *** Abaqus/Python secondary development technology provides engineers with enough flexibility to combine the substructure method with an iteration algorithm,which enables the creation of a parametric modeling calculation for cooling water *** paper proposes such a method,which involves iterating the water pipe boundary and establishing the water pipe unit substructure to numerically simulate the concrete temperature field that contains a cooling water *** verify the feasibility and accuracy of the proposed method,two classic numerical examples were *** results showed that this method has good applicability in cooling pipe *** the value of the iteration parameterαis 0.4,the boundary temperature of the cooling water pipes can meet the accuracy requirements after 4∼5 iterations,effectively improving the computational ***,this approach provides a useful tool for engineers to analyze the temperature control measures accurately and efficiently for mass concrete,such as cooling water pipes,using Abaqus/Python secondary development.

关键词： Fourier equation cooling water pipe mass concrete iteration algorithm

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Aloin ameliorates cecal ligation and puncture-induced sepsis in mice by attenuating inflammation and modulating gut microbiota

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Food Science and Human Wellness 2024年

作者： Jingqian Su Jianbin Xiao Siyuan chen heng Zhao Xiaoni zhang Zhihua Feng Kunsen chen Biyun Guan Wenzhi chen Youqiang chen Duo chen Qi chen Fujian Key Laboratory of Innate Immune Biology Biomedical Research Center of South China College of Life Science Fujian Normal University The Public Service Platform for Industrialization Development Technology of Marine Biological Medicine and Products of the State Oceanic Administration Fujian Key Laboratory of Special Marine Bioresource Sustainable Utilization Southern Institute of Oceanography College of Life Science Fujian Normal University

Most Aloe species are used as new food or functional food ingredient. Even though widely known for its health benefits， the anti-inflammatory effects and underlying mechanisms of Aloin (Alo)， an anthraquinone compound isolated from plant species of the genus Aloe， remain unidentified. Here， we investigated the protective effects of Alo against cecal ligation and puncture (CLP)-induced sepsis and microflora in mice. Alo significantly improved CLP-induced sepsis and the survival rate of septic mice， downregulated the expression of proinflammatory factors， and decreased the infiltration of inflammatory cells in tissues. Alo upregulated the proportion of peritoneal macrophages， reduced the number of peritoneal bacteria， decreased the content of short-chain fatty acids and bile acids in the abdominal cavity， and suppressed TLR-2/4/NF-κB/NLRP3/Caspase-1/3/8 signaling. Furthermore， Alo altered the composition of the microbiome and promoted the growth of Lactobacillus， which showed a stronger anti-inflammatory effect. Whole-genome analysis identified the genes Saa3， Il10， Fpr1， and Eif4a1 associated with the protective effects of Alo in mice with CLP-induced sepsis. Overall， our results provide novel insights into the therapeutic potential and mechanism of action of Alo in the treatment of sepsis.

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Body-force modeling considering induced upstream effects for a transonic compressor with total temperature distortion

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Chinese Journal of Aeronautics 2024年第6期37卷 7-19页

作者： Jiahui QIU chen YANG Wenqiang zhang Min zhang Juan DU Digital Twin Research Center Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Engineering and Science University of Chinese Academy of SciencesBeijing 100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Chinese Academy of SciencesBeijing 100190China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

To numerically study the impact of total temperature distortion on a transonic compressor with reduced computational costs,a Body-Force Model(BFM)is ***,the interactions between the distorted flow and the compressor are analyzed using full-annulus Unsteady Reynolds-Averaged Navier-Stokes(URANS)results and the orbit *** is found that the induced swirl distortion and the mass flux nonuniformity are intensified in the compressor upstream flow field.A correction factor is thus added to the BFM to account for the effect of the induced swirl,which is crucial for the accurate representation of distortion transfer in the ***,steady simulations with large-amplitude 180circumferential total temperature distortion are performed using the developed *** is shown that the distorted compressor map simulated with the BFM matches well with URANS *** circumferential phase shift of total temperature and the generation of the additional total pressure distortion across the rotor are in line with the time-averaged URANS flow *** compressor upstream effects on the distorted inflow can also be exactly *** above-mentioned results demonstrate the BFM developed in this paper can effectively capture the distorted flow features inside the compressor,and significantly reduce the computational costs by five orders of magnitude compared with URANS.

关键词： Upstream effect Orbit method Induced swirl distortion Body force model Correction factor Time-averaged URANS

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