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The potential of Ca isotopes to trace subducted marine carbonates in deep mantle

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Journal of Oceanology and Limnology 2025年第1期43卷 29-40页

作者： Hongli ZHU Renqiang LIAO Long DU Zhaofeng ZHANG Key Laboratory of Ocean Observation and Forecasting Center of Deep Sea ResearchInstitute of OceanographyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China College of Earth science and Engineering Shandong University of Science and TechnologyQingdao 266590China research center for planetary science College of Earth SciencesChengdu University of TechnologyChengdu 610059China

Marine carbonates,the major carrier of carbon upon the upper crust,can be subducted into the Earth’s interior along with oceanic crust,and then returned to the surface through magmatism,which constitute the deep carbon *** process plays an important role in modulating the CO_(2) concentrations in the atmosphere over geologic time,and thus the forming of the habitable ***,identifying recycled marine carbonates in the mantle is critical to well understand the global deep carbon *** is one of the major constituent cations in marine carbonates and its isotopes may be a potential tracer for recycled marine carbonates in the *** further evaluate the capability and challenges of Ca isotopes as such a geochemical tracer,we reviewed the Ca isotopic compositions in important reservoirs and the behavior of Ca isotopes during high-temperature geological processes that are related to the deep carbon cycle,including plate subduction,mantle metasomatism,mantle partial melting,magma differentiation,*** studies show that carbonate-rich marine sediments have significantly lowerδ^(44/40) Ca than the Earth mantle,and metasomatism by such recycled materials can cause lighter Ca isotopic compositions in deep mantle-derived rocks than those of the depleted mantle and mid ocean ridge ***,the Ca isotopic fractionation during partial melting of mantle peridotites is small(~0.10‰)and the Ca isotopic fractionation during plate subduction and intermediate-mafic magma evolution is *** investigations suggest that Ca isotopes have great advances in tracing such recycled materials in the ***,other processes(such as the influence by partial melts of eclogites)may induce similar effects on mantle-derived rocks as subducted marine carbonates but still remains debated,and thus further investigations are strongly needed in the future.

关键词： Ca isotope marine carbonate mantle metasomatism partial melting fractional crystallization

Space weathering characteristics of lunar permanently shadowed regions soils:Evidence from experimental simulation

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Acta Geochimica 2025年第1期44卷 1-10页

作者： Zixuan Han Yang Li Chen Li Ronghua Pang Sizhe Zhao Zhuang Guo Kairui Tai Rui Li Zhenhao Hu Li Liu center for Lunar and planetary sciences Institute of GeochemistryChinese Academy of SciencesGuiyangChina University of Chinese Academy of sciences BeijingChina center for Excellence in Comparative Planetology Chinese Academy of SciencesHefeiChina State Key Laboratory of Lunar and planetary sciences Macao University of Science and TechnologyMacaoChina NWU-HKU Joint center of Earth and planetary sciences Department of GeologyNorthwest UniversityXi’anChina International center for planetary science Chengdu University of TechnologyChengduChina Deep Space Exploration Lab BeijingChina

Permanently shadowed regions(PSRs)on the Moon are potential reservoirs for water ice,making them hot spots for future lunar *** water ice in PSRs would cause distinctive changes in space weathering there,in particular reduction-oxidation processes that diff er from those in illuminated *** determine the characteristics of products formed during space weathering in PSRs,the lunar meteorite NWA 10203 with artifi cially added water was irradiated with a nanosecond laser to simulate a micro-meteorite bombardment of lunar soil containing water *** TEM results of the water-incorporated sample showed distinct amorphous rims that exhibited irregular thickness,poor stratifi cation,the appearance of bubbles,and a reduced number of npFe^(0).Additionally,EELS analysis showed the presence of ferric iron at the rim of the nanophase metallic iron particles(npFe^(0))in the amorphous rim with the involvement of *** results suggest that water ice is another possible factor contributing to oxidation during micrometeorite bombardment on the lunar *** addition,it off ers a reference for a new space weathering model that incorporates water in PSRs,which could be widespread on asteroids with volatiles.

关键词： Space weathering Permanently shadowed regions The Moon laser irradiation Water ice

Tectonic modes of mantle convection and their implications for Earth's tectonic evolution based on three-dimensional numerical simulations

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science China Earth sciences 2025年第1期68卷 270-296页

作者： Song XIANG Jinshui HUANG Bingcheng WU School of Earth and Space sciences University of Science and Technology of ChinaHefei230026China CAS center of Excellence in Comparative planetary Studies Hefei230026China

Five tectonic modes of mantle convection are obtained and analyzed with three-dimensional numerical models in a spherical shell *** five tectonic convective modes are non-plate mobile-lid,plate-like mobile-lid,episodic plate-like mobile-lid,episodic stagnant-lid,and stagnant-lid convective modes,*** typical characteristics of these five tectonic modes and their numerical classification criteria based on plateness,mobility,and their standard deviations are presented and *** results show that the yield stress of the lithosphere has profound effects on the tectonic convective *** the gradual increase of yield stress,the tectonic mode of mantle convection changes from one to another sequentially through the aforementioned five ***,as the Rayleigh number increases,the range of yield stress for the platelike mobile-lid convective mode decreases,and the dimensionless transition stress between different tectonic modes ***,the dimensional transition stress between the non-plate mobile-lid convective mode and plate-like mobile-lid convective mode increases with the increase of Rayleigh number,but decreases between other tectonic ***,we find that the transition stress between different tectonic modes is inversely proportional to the internal heating rate,with the transition stress decreasing as the internal heating rate *** fitting analysis of the transition stress between tectonic modes shows that Earth's current plate tectonics correspond to a lithospheric yield stress of 150–250 MPa,which aligns with the strength of serpentinized mantle rock determined by experimental *** the Archean mantle was 300℃warmer than it is today,then the Earth was in an episodic stagnant-lid convective *** tectonic evolution of the Earth's surface is closely related to the lithospheric strength and the process of thermal *** the lithospheric strength was only 150 MPa,plate tecton

关键词： Tectonic mode of mantle convection Plate-like mobile-lid convection Episodic plate-like mobile-lid convection Episodic stagnant-lid convection Plate tectonics and tectonic evolution of the Earth

Synthesis of intermetallic PtCo fuel cell catalysts from bimetallic core@shell structured nanoparticles

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Journal of Energy Chemistry 2025年第2期101卷 1-6页

作者： Le Zhang Lei Tong Shuai Li Chang-Song Ma Kun-Ze Xue Hai-Wei Liang Hefei National research center for Physical sciences at the Microscale Department of Chemistry University of Science and Technology of China

The high activity and stability of intermetallic PtCo nanocatalysts toward oxygen reduction reaction make them a top candidate as low-Pt cathode catalysts in proton exchange membrane fuel cells（PEMFCs）.However,forming intermetallic structures typically requires high-temperature annealing,posing a challenge for achieving well-size control and highly ordered *** we report the design and synthesis of bimetallic co re@shell structured precursors for affording high-performance intermetallic PtCo *** fabrication of the core@shell precursor involves using a molecular ligand containing both sulfur and oxygen donors to selectively bind with Pt colloidal nanoparticles as the core and chelate Co ions as the *** high-temperature annealing,the ligand transforms into carbon coatings around alloy nanoparticles,preventing particle sintering;meanwhile,Co ions in the shell can easily diffuse into the Pt core,which helps to increase the thermodynamic driving force for forming intermetallic *** benefits enable us to obtain the catalyst with finely dispersed nanoparticles（～3.5 nm）and a high ordering degree of 72%.With 0.1 mgPt/cm2cathode loading,the catalyst delivers superior performance and durability in PEMFCs,showing an initial mass activity of 0.56 A/mgPt,an initial power density of 1.05 W/cm2at 0.67 V（H2-air）,and a voltage loss of 26 mV at 0.8 A/cm2after the accelerated durability test.

关键词： Bimetallic structure Fuel cells Intermetallic PtCo Oxygen reduction reaction

Managing virus diseases in citrus:Leveraging high-throughput sequencing for versatile applications

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Horticultural Plant Journal 2025年第1期11卷 57-68页

作者： Hongming Chen Zhiyou Xuan Lu Yang Song Zhang Mengji Cao Integrative science center of Germplasm Creation in Western China(Chongqing)science City Citrus Research InstituteSouthwest UniversityChongqing 400712China National Citrus Engineering research center Citrus Research InstituteSouthwest UniversityChongqing 400712China

In this review,the advantages and advances in applying high-throughput sequencing(HTS)in the management of viral diseases in citrus,along with some challenges,are discussed to provide perspectives on future *** the initial implementation of HTS in citrus virology,a substantial number of citrus viruses have been identified,with a notable increase in the last 7 *** acquisition of viral genomes and various HTS-based omics analyses serve as crucial pillars for advancing research in the etiology,epidemiology,pathology,evolution,ecology,and biotechnology of citrus *** has notably contributed to disease diagnosis,such as the diagnoses of concave gum and impietratura,as well as to the surveillance of new virus risks and the preparation of virus-free ***,certain inherent defects in HTS and coupled bioinformatics analysis,such as challenges with sequence assembly and the detection of viral dark matter,require improvement to enhance practical *** addition,the utilization of HTS for the systematic management of citrus viral diseases remains limited,and drawing insights from other virus-plant pathosystems while integrating emerging compatible techniques and ideas may broaden its specific applications.

关键词： Deep sequencing Virus epidemics Functional genomics CRISPR/Cas Virus-host interactions

Radiation belt electron wisp inside South Atlantic Anomaly due to terrestrial VLF transmitter observed by MSS-1

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science China Earth sciences 2025年第2期68卷 538-548页

作者： Yixin SUN Ying LIU Qiugang ZONG Yixin HAO Hong ZOU Yuguang YE Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China State Key Laboratory of Lunar and planetary science Macao University of Science and TechnologyMacao 999078China Max Planck Institute for Solar System research Goettingen 37077Germany

The South Atlantic Anomaly represents a region within near-Earth space characterized by a significantly weaker geomagnetic field and a higher flux of energetic particles compared to other areas. It is a space weather hazards to Low-EarthOrbit satellites. There has been evidence that the Very Low Frequency(VLF) waves from the powerful ground VLF radio transmitter in Australia, known as NWC, have the capacity to scatter energetic electrons' pitch angle in the inner radiation *** scattering directs electrons into the drift loss cone, forms a “wisp”, characterized by its peak intensity outside the South Atlantic Anomaly(SAA), and a “rift” exhibiting minimal intensity within SAA. Our findings mark the initial observation of a“wisp” precipitation, an unusual occurrence with peak intensity detected inside the SAA, observed via the Macao science Satellite-1. Enabled by the Medium-energy Electron Spectrometer onboard Macao science Satellite-1, we were able to comprehensively measure the full pitch angle distribution at Low-Earth-Orbit. This allowed us to attribute the “wisp” within the anomaly to a specific pitch angle range just outside the drift loss cone, a measurement unattainable by previous satellites. This“wisp” occurrence aligns with previous model predictions, despite being overlooked. Moreover, we distinguished between the trapped and precipitating electron populations. Directly derived from the ratio of these populations, our analysis revealed that approximately 2%-5% of trapped electrons will be lost in this specific wisp due to the influence of the ground VLF *** results not only complement existing evidence of energetic electron pitch angle scattering facilitated by the ground VLF transmitter but also offer a quantitative estimation of its impact.

关键词： South Atlantic Anomaly Radiation belts Electrons precipitation VLF transmitter Wave-particle interaction

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Electronic interactions between neighboring functionalized guest Sb single atoms and Pt clusters enhance CO tolerance

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Journal of Energy Chemistry 2025年第2期101卷 733-743页

作者： Wenkang Miao Ronghui Hao Lu Gan Wanyin Xu Zihan Wang Wenxin Lin Heguang Liu Yinchun Lyu Qianqian Li Jinyang Xi Anmin Nie Jinsong Wu Hongtao Wang Materials Genome Institute Shanghai University School of Materials science and Engineering Zhejiang Sci-Tech University School of Materials science and Engineering Xi'an University of Technology center for High Pressure science State Key Laboratory of Metastable Materials Science and Technology Yanshan University Nanostructure research center Wuhan University of Technology center for X-mechanics Zhejiang University

Platinum-based（Pt） catalysts are notoriously susceptible to deactivation in industrial chemical processes due to carbon monoxide（CO） *** this poisoning deactivation of Pt-based catalysts while enhancing their catalytic activity,selectivity,and durability remains a major ***,we propose a strategy to enhance the CO tolerance of Pt clusters（Pt_n） by introducing neighboring functionalized guest single atoms（such as Fe,Co,Ni,Cu,Sb,and Bi）.Among them,antimony（Sb） single atoms（SAs） exhibit significant performance enhancement,achieving 99% CO selectivity and 33.6% CO2conversion at 450℃,Experimental results and density functional theory（DFT） calculations indicate the optimization arises from the electronic interaction between neighboring functionalized Sb SAs and Pt clusters,leading to optimal 5d electron redistribution in Pt clusters compared to other functionalized guest single *** redistribution of 5d electrons weaken both the σ donation and π backdonation interactions,resulting in a weakened bond strength with CO and enhancing catalyst activity and *** situ environmental transmission electron microscopy（ETEM） further demonstrates the exception thermal stability of the catalyst,even under H2at 700℃.Notably,the functionalized Sb SAs also improve CO tolerance in various heterogenous catalysts,including Co/CeO2,Ni/CeO2,Pt/Al2O3,and Pt/*** finding provides an effective approach to overcome the primary challenge of CO poisoning in Pt-based catalysts,making their broader applications in various industrial catalysts.

关键词： CO tolerance Electronic effect Functionalized guest single atoms In-situ TEM Pt cluster

Leveraging ROTI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan N.Muafiry Teguh N.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik T.Wibowo Febrylian F.Chabibi Umar A.Ahmad Wildan P.Tresna Asnawi research center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management Facilities and science and Technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia research center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia research center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and planetary sciences Hokkaido UniversitySapporoJapan

This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude ***-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this *** generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the ROTI maps of Ina-CORS are ***,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of TEC change index(ROTI)map

Simulations of electron zebra stripes in the inner radiation belt using a composite empirical electric field model

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science China Earth sciences 2025年第1期68卷 27-38页

作者： Ziyang WANG Ying LIU Qiugang ZONG Hong ZOU Yuguang YE Xuzhi ZHOU Chao YUE Shan WANG Institute of Space Physics and Applied Technology Peking UniversityBeijing100871China State Key Laboratory of Lunar and planetary science Macao University of Science and TechnologyMacao999078China

The phenomenon termed“zebra stripes”manifests as regular patterns in the energy-space(L shell)spectrum of energetic electrons(ranging from tens to hundreds ke V)within the inner radiation *** structures exhibit drift-periodic behavior and commonly arise from large-scale electric field perturbations near the substorm *** this study,we introduce a composite electric field model and replicate the formation,structure,and evolution of zebra stripes using a bounce-averaged test particle code under this electric field ***-resolution measurements of energetic electrons obtained from the Van Allen Probes and the recently launched Macao science Satellites-1 are used as initial conditions and served to validate our test particle *** analyses between observed data and simulations demonstrate our test particle method's efficacy in capturing zebra stripes'general ***,the composite model proves capable of reproducing realistic variations in the electric field within the inner radiation belt to a certain ***,subtle differences emerge in the flux strength and the positions of *** disparities primarily stem from limitations inherent in the electric field model and the initial conditions of the *** that the model represents an average case,it is conceivable that real-world scenarios may deviate from the average,thereby introducing variations in the observed phenomena.

关键词： Zebra stripes Inner radiation belt Large-scale electric fields Van Allen Probes Macao science Satellite