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Cold and humid climates enrich soil carbon stock in the Third Pole grasslands

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The Innovation 2024年第1期5卷 9-10页

作者： Yanfen Wang Anquan xia Kai xue College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of SciencesBeijing 101408China State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining 810016China Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810001China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou 256606China

As a unique geographic unit,the Third Pole is globally recognized as the largest and highest mountainous *** amounts of soil organic carbon(SOC)are stored in this region,whose top layer is active in biochemical processes and highly sensitive to environmental *** warming intensity in the Third Pole has been predicted to be at least 0.3℃ higher than the global average by the end of the 21^(st) century.1 Therefore,it is essential to understand the underlying mechanisms,especially the hydrothermal factors,controlling the top layer SOC in the Third *** may help to predict the dynamics of soil carbon stock in future climate scenarios.

关键词： soil mountainous globally

Photocatalytic vinyl radical-mediated multicomponent 1,4-/1,8-carboimination across alkynes and olefins/(hetero)arenes

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Science China Chemistry 2024年第2期67卷 558-567页

作者： Shan-Shan Li Yu-Shi Jiang xue-Ling Luo Xuming Ran Yuqiang Li Dong Wu Cheng-xue Pan Peng-Ju xia School of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityGuilin541004China Shanghai Artificial Intelligence Laboratory Shanghai200433China The Institute for Advanced Studies Wuhan UniversityWuhan430064China

We developed a highly selective and efficient multicomponent transformation by utilizing alkynes and olefins/(hetero)arenes through photoinduced energy-transfer *** reaction involves the formation of three distinct chemical bonds,namely C(sp~3)–C(sp~2),C(sp~2)–C(sp~3),and C(sp~3)–N,in a single coordinated *** strategy used a vinyl radical-mediated radical relay approach under mild conditions,exhibiting a broad substrate scope(>70 examples),excellent functional-group tolerance,and remarkable regio-and *** the utilization of a combination of experimental techniques and density functional theory(DFT),we delved deeper into the mechanistic intricacies of this distinctive *** revealed that the selective radical addition to electron-deficient alkynes,rather than olefins,was governed by the inherent reactivity of alkyl *** discovery presented a highly effective approach for the synthesis of stereodefined multisubstituted alkenes.

关键词： alkyne-olefin coupling DFT studies regio-and anti-stereoselectivity multisubstituted alkenes

Enhancing reversible hydrogen storage performance of 2LiBH4–MgH2 via in-situ building heterogeneous nucleation sites

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Rare Metals 2024年第9期43卷 4367-4376页

作者： Wei Chen Ya-Hui Sun Tian Xu xue-Bin Yu Guang-Lin xia Department of Materials Science Fudan University

2LiBH4-MgH2composite is one of the most attractive reactive hydride composites with a theoretic hydrogen capacity of 10.8 wt%.However,the large nucleation restriction of MgB2during the second step of dehydrogenation results in sluggish hydrogen storage kinetics and high operating temperature,which hinders its practical application as on-board hydrogen storage ***,Al3Ti doped Al nanoparticles （AT NPs） are prepared by a facile chemical reduction reaction to improve the hydrogen storage performance of *** the initial H2desorption process,MgAlB4and TiB2that have identical crystal structure and low d-value mismatch with MgB2resulting from the reaction between AT NPs and 2LiBH4-MgH2composite serve as effective nucleation sites for the formation of *** a result,the apparent activation energy of the two-step H2desorption of AT NPs doped 2LiBH4-MgH2composite are notably decreased to （110.0±5.9） and（119.6±1.4） kJ·mol-1,which is 55.5 and 33.5 kJ·mol-1lower than that of the undoped *** importantly,a reversible hydrogen storage capacity of 9.2 wt%after 10cycles of H2desorption and adsorption could be achieved,corresponding to a capacity retention rate of 99%.The building of reactive bimetallic catalyst towards in situ formation of heterogeneous nucleation sites provides a new strategy for improving the hydrogen storage performance of reactive hydride composites.

关键词： Catalytic effects Heterogeneous nucleation Reactive hydride composites Reversible hydrogen storage

Efficacy of rapid antigen self-testing for SARS-CoV-2 screening:Real-world evidence from a prospective cohort study

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Genes & Diseases 2024年第5期11卷 88-90页

作者： Yaoyue Hu Bin Peng Jie Fan zhu Yang Jianjiang xue Quanxin Long Jie xia Yuan Hu xuefei Cai Li Zhou Ailong Huang School of Public Health Chongqing Medical UniversityChongqing 400016China The Second Affiliated Hospital of Chongqing Medical University Chongqing 400016China Clinical Laboratory University-Town Hospital of Chongqing Medical UniversityChongqing 401331China Key Laboratory of Molecular Biology on Infectious Diseases Designated by the Chinese Ministry of Education Chongqing Medical UniversityChongqing 400016China

Antigen rapid diagnostic tests(Ag-RDTs)have been considered and implemented as an important diagnostic and screening tool to identify SARS-CoV-2 infections in community settings.1 Ag-RDTs are less sensitive,particularly in asymptomatic populations,compared with laboratorybased viral nucleic acid amplification tests(NAATs)such as reverse transcription polymerase chain reaction(RT-PCR).2 However,taking into account the facts that Ag-RDTs are effective for identifying most contagious individuals,they are faster and less expensive than RT-PCR,as well as that RT-PCR could produce positive results for weeks to months after the infection,2 WHO recommends Ag-RDTs be offered as COVID-19 self-testing for screening purposes in addition to professionally administered testing services regardless of the community transmission level.

关键词： testing faster rapid

Zircon Zr isotope fractionation during crustal anatexis

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Science China Earth Sciences 2024年第8期67卷 2495-2506页

作者： Erlin zhu Qiongxia xia Zhaoya LI Renxu CHEN James VAN ORMAN School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Lithospheric and Environmental Coevolution Hefei 230026China Frontiers Science Center for Planetary Exploration and Emerging Technologies University of Science and Technology of ChinaHefei 230026China Department of Earth Environmental and Planetary SciencesCase Western Reserve UniversityCleveland OH 44106USA

Zirconium is one of high field strength elements but its isotope behavior during geochemical processes is still uncertain because of the limited *** Zr isotopes in magmatic rocks are often used to trace the evolution of magmas through fractional crystallization,it is intriguing how highly heterogeneous Zr isotopes were produced by the growth of zircon during crustal *** address this issue by in-situ zircon Zr isotope analyses of migmatites from two high-temperature metamorphic terranes in the South Lhasa zone and the North Dabie zone,respectively,in *** results show highly variable δ^(94)Zr values from-0.30‰ to +0.81‰ and from-0.58‰ to +0.49‰,*** addition to the relict zircon of magmatic origin,two types of newly-grown zircons were identified in terms of their occurrences,trace elements and δ^(94)Zr *** peritectic zircon,mainly occurring in the in-situ leucosomes,exhibits the highest Nb-Ta-Hf-U contents and variably higher δ^(94)Zr values than those of the relict *** anatectic zircon,mainly occurring in the leucocratic veins,shows higher Nb-Ta-Hf-U contents than and similar δ^(94)Zr values to those of the relict *** calculations demonstrate that the variable Zr isotope compositions of newly-grown zircons would result from decoupled release of Zr from zircon and non-zircon *** Zr supply of the peritectic zircon is mainly derived from the decomposition of Zr-bearing minerals in the in-situ anatectic melt(the non-zircon effect),whereas the Zr supply of the anatectic zircon is mainly from the dissolution of pre-existing zircons in the evolved melt(the zircon effect).The significant Zr isotope variations in the migmatites well illustrate the generation,migration and accumulation of the anatectic melts during the partial ***,Zr isotopes can be used as a powerful means for distinguishing between the peritectic and anatectic zircons during crustal anatexis.

关键词： Zr isotopes Zircon effect Non-zircon effect Migmatite Crustal anatexis

High-entropy design boosts dielectric energy storage

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Rare Metals 2024年第8期43卷 4013-4015页

作者： Qiu-Ying xia He zhu Si Lan Yang Ren Herbert Gleiter Institute of Nanoscience School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China Department of Physics City University of Hong KongHong Kong999077China

Dielectric capacitors are vital for advanced electronic and electrical power systems due to their impressive power density and ***,a persistent challenge has been enhancing their energy densities while maintaining high *** in Science,a novel high-entropy design for relaxor ferroelectric materials has been proposed,promising significant improvements in both energy density and efficiency for multilayer dielectric ceramic *** the crucial role of high-entropy design in energy storage materials and devices,this highlight focuses on interpreting the progress and significance of this innovative work.

关键词： ceramic dielectric energy

Recent Advance in Electrocatalytic Water Splitting for Hydrogen Production by Layered Double Hydroxides

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Chemical Research in Chinese Universities 2024年第4期40卷 577-589页

作者： xia Tian REN Qinghui YANG Jiangrong LI Zhenhua SHAO Mingfei DUAN xue State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing100029P.R.China Quzhou Institute for Innovation in Resource Chemical Engineering Quzhou324000P.R.China

Collecting green hydrogen(H2)from water splitting driven by renewable energy is a new competition to implement the construction of H2 energy industry and promote new economic growth for global *** common strategy to enhance the efficiency of H2 production is to reduce the potential of electrolytic cell that is the mainstream way to prepare efficient *** double hydroxides(LDHs)are one of the most active electrocatalysts with adjustable active sites in contemporary *** this review,we discuss the recent advanced progress of LDHs for hydrogen evolution reaction(HER)on cathode and oxygen evolution reaction(OER)or organic oxidation on anode and emphasize the influence of LDHs structure regulation in water electrolysis process(HER/OER)as well as the current development status of organic oxidation catalyzed by active oxygen species on ***,we propose the current challenges of LDHs in electrocatalysis and prospect their developing tendency and further application.

关键词： Layered double hydroxide Hydrogen production Hydrogen evolution reaction(HER) Oxygen evolution reaction(OER) Electrocatalytic organic oxidation

Tribological properties of Al-GNP composites at elevated temperature

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Friction 2024年第5期12卷 1028-1041页

作者： Sunil POUDEL Rizwan BAJWA Yongde xia Zakir KHAN Yi ZHANG Yanqiu zhu College of Engineering Mathematics and Physical SciencesUniversity of ExeterExeterEX44QFUK European Technical Centre Daido Metal Co.Ltd.Iliminster SomersetTA199PHUK

Lighter and more powerful next generation vehicles and other rotary machinery demand bearings to operate in harsher conditions for higher efficiency,and the continuous development of advanced low-wear and friction materials is thus becoming even more important to meet these *** aluminium composites reinforced with high performance lubricate phases such as graphene nanoplatelets(GNPs)are very promising and have been vigorously *** maintaining a low coefficient of friction(COF)and offering great strength against wear due to their self-lubricating capability,the solid lubricant like GNPs protect the bearing surface from wear damage and prevent change in metallurgical properties during temperature *** paper first studies the high-temperature tribological performance of aluminium matrix composites reinforced with GNP,consolidated via powder metallurgy,then elucidates their tribological *** report that the best tribological performance is achieved by the composite containing 2.0 wt%GNP,with an extraordinarily low COF of 0.09 and a specific wear rate of 3.5×10^(−2)mm^(3)·N^(−1)·m^(−1),which represent 75%and 40%reduction respectively,against the plain aluminium consolidated under identical *** in-track and out-of-track Raman analysis have confirmed the role of GNPs in creating a tribofilm on the counterpart surface which contributed to the excellent performance.

关键词： nanocomposite graphene nanoplatelet(GNP) tribology powder metallurgy

The Geology, Fluid Inclusions, and O-S Isotopes of the Mibei Gold Deposit, Hunan Province, Southern China

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 992-1006页

作者： xue Wenhao LIANG Yayun LI xiaofeng LI Mingyi XIE Wenbo PENG xue xia Rui HE Hongsheng xiaO Jincheng School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Geophysical and Geochemical Survey Institute of Hunan Changsha 410116China New Geological Energy Exploration and Development Engineering Technology Research Center of Hunan Changsha 410116China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Beijing)Beijing 100083China Comprehensive Survey Command Center for Natural Resources China Geological SurveyBeijing 100055China

The Mibei gold deposit,located in the southwestern part of the xuefengshan uplift zone,the middle section of the Jiangnan orogenic belt in southern China,has estimated gold resources of approximately seven *** deposit is primarily a quartz vein-type gold deposit,with ore bodies occurring mainly within Neoproterozoic *** main metallic minerals in the ore are pyrite,chalcopyrite,and *** this study,the petrography and microthermometry of ore-forming fluid inclusions,oxygen isotopes of gold-bearing quartz,and sulfur isotopes of goldbearing sulfides and arsenopyrite were *** types of fluid inclusions were identified:type Ⅰa three-phase inclusions comprising vapor and two phases of liquids(V_(CO_(2))+L_(CO_(2))+L_(H2O)),type Ⅰb two-phase liquids(L_(CO_(2))+L_(H2O)),typeⅡ two-phase vapor-rich inclusions(V/V+L> 50%),and type Ⅲ pure liquid *** Ⅰ inclusions were heated uniformly to the liquid phase,type Ⅱ inclusions were heated uniformly to the gas phase,and type Ⅲ inclusions were heated without *** general,the temperature range of homogenization to liquid phase of fluid inclusions in the Mibei gold deposit is 204-227℃.The salinity of the inclusion ranges from 4.6 to 12.2 wt% NaCl *** δ~(18)O_(SMOW) of gold-bearing quartz varies from 16.9‰ to 17.5‰.The δ~(18)O_(H2O) of gold-bearing quartz are varied from 6.5‰ to 7.5‰.The δ~(34)S values of gold-bearing pyrite range from 1.7‰ to 6.8‰.The δ~(34)S values of gold-bearing arsenopy rite range from 5.6%o to 5.9‰.Theδ~(34)S values of pyrite from wall rocks slate range from 6.4‰ to 11.6‰.This evidence implies that the ore-forming fluids of the Mibei gold deposit originated from magmatic-hydrothermal processes,mixing with minor S from the surrounding *** with the evolution of the Jiangnan orogenic belt,due to the magmatic and tectonic activities of the xuefengshan uplift during the Caledonian period,the fault seal mechanism controlled the ore-forming p

关键词： ore-forming fluid ore genesis Mibei gold deposit xuefengshan uplift zone Jiangnan orogenic belt