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Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang Li Yu Liu Xiao-Xiao Ling Li-Guang Wu Li Yang Lan Yang Bo Yang Yong-Gang Zhao Xian-Hua Li state key laboratory of Lithospheric evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education key laboratory of Orogenic Belts and Crustal evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD state key laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

Multifunctional MXene/rGO aerogels loaded with Co/MnO nanocomposites for enhanced electromagnetic wave absorption,thermal insulation and pressure sensing

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Nano Research 2024年第9期17卷 7803-7813页

作者： Chan Guo Shiping Shao Xin Zhang Yunxiang Tang Luxue Wang Jiurong Liu Lili Wu Ke Bi Fenglong Wang key laboratory for Liquid-Solid Structural evolution and Processing of Materials Ministry of Education Shandong UniversityJinan 250061China state key laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

Aerogel-based composites hold promising application prospects as potential electromagnetic wave(EMW)absorption materials,yet the construction of such materials with ingenious microstructures,appropriate magnetic/dielectric multi-components,and integrated multifunctionality remains considerably ***,a multicomponent Co/MnO/Ti_(3)C_(2)T_(x) MXene/rGO(CMMG)hybrid aerogel featured with three-dimensional(3D)vertical directional channel architecture is *** from the synergistic effect arising from the 3D conductive networking structure,diverse heterogeneous interfaces,magnetic/dielectric multicomponent,and multiple loss pathways,the optimized CMMG-2 aerogel delivers fascinating EMW absorption capabilities,characterized by a minimal reflection loss(RL_(min))of-77.41 dB and an effective absorption bandwidth(EAB)of 6.56 ***,the remarkable hydrophobicity,exceptional thermal insulation capabilities,and outstanding photothermal properties of CMMG-2 aerogel make it highly promising for multiple application in diverse and demanding ***,the distinctive pore structure of hybrid aerogel also allows it for sensitive and reliable detection of electrical signals caused by pressure changes and human ***,this research provides a viable design strategy for the development of lightweight,efficient,and multifunctional aerogel-based EMW absorption materials for various application scenarios.

关键词： electromagnetic wave absorption Ti_(3)C_(2)qT_(x)MXene reduced graphene oxide magnetic-dielectric nanoparticles multifunctional aerogel

Pd cluster decorated free standing flexible cathode for high performance Li-oxygen batteries

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Nano Research 2024年第4期17卷 2678-2686页

作者： Liang Guo Guoliang Zhang Ruonan Yang Dongmei Zhang Xiuqi Zhang Han Yu Xia Li Feng Dang key laboratory for Liquid-Solid Structure evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

As a promising candidate for the next generation energy storage system,rechargeable lithium-oxygen batteries(LOBs)still face substantial challenges caused by insulating discharge products that preclude their practical *** highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance ***,Pd decorated Te nanowires(Pd@Te NWs)were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect,in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ***,Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode,enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm^(-2).Experimental studies and density functional theory(DFT)calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te,in which uniform electron distribution,extensive electron exchange,and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products,while the high adsorption energy of Te substrate for Li species reduces the initial dynamical energy barrier during discharging *** current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects.

关键词： flexible lithium-oxygen batteries Pd@Te synergistic catalysis cathode catalysts density functional theory(DFT)calculation

The Origin of Mesozoic A-type Granitoids,Fujian Province,Southeast China:Insights from Geochronology,Mineralogy and Geochemistry

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 630-640页

作者： XIE Qifeng DONG Yunpeng CAI Yuanfeng ZHAI Mingguo XIAO Aifang ZHANG Hong Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China state key laboratory of Continental Dynamics Northwest UniversityXi’an 710069China state key laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210023China state key laboratory of Lithospheric evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still *** results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 Ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.The Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock *** samples are enriched in HFSEs(i.e.,Ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of *** the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_(N),10000×Al/Ga,Rb/Nb and Nb/Ta etc.,they were proved to be alkaline A-type *** the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization *** values of ε_(Hf)(t)and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement *** comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate.

关键词： A-type granitoid geochronology extension subduction Mesozoic Southeast China

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Spatial continuous modeling of early Cenozoic carbon cycle and climate

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National Science Review 2024年第4期11卷 30-32页

作者： Yonggang Liu Jian Zhang Haoyue Zuo Zhilin He Jiaqi Guo Qifan Lin Haonan Yu Jiawenjing Lan Jing Han Zhihong Song Zihan Yin Liang Zhao Yongyun Hu Zhengtang Guo laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University key laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences state key laboratory of Lithospheric evolution Institute of Geology and Geophysics Chinese Academy of Sciences

The partial pressure of atmospheric CO2（pCO2） is determined by the carbon cycle that involves climate, biogeochemistry, and plate tectonics. In this cycle,atmospheric CO2is converted into organic carbon and carbonates by biological activities and silicate weathering, and buried as sediments. The sediments on the ocean floor are subducted into the Earth’s interior, and subsequently converted back into CO2and outgassed into the atmosphere.

关键词： ATMOSPHERIC CO2

Autotomy does not affect the locomotor performance of a scorpion

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Integrative Zoology 2024年第2期19卷 336-338页

作者： Aijia MAO Shichang ZHANG Centre for Behavioral Ecology and evolution State Key Laboratory of Biocatalysis and Enzyme EngineeringSchool of Life SciencesHubei UniversityWuhanChina

Autotomy,the self-induced loss of a body part,is one of the most extreme forms of defense against *** occurs in a variety of animal taxa,including both vertebrates and invertebrates(Fleming et al.2007).The most commonly seen examples are spiders,lizards,and crustaceans(Emberts et al.2019)(Fig.1).By performing the autotomy behavior,animals can effectively survive predation or non-predatory entrapment,or reduce the cost of injury(Emberts et al.2019;Wuthrich et al.2022).

关键词： scorpion extreme performance

Chasing Sequencing Perfection:Marching Toward Higher Accuracy and Lower Costs

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Genomics, Proteomics & Bioinformatics 2024年第2期22卷 1-12页

作者： Hangxing Jia Shengjun Tan Yong E.Zhang CAS key laboratory of Zoological Systematics and evolution&state key laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Animal evolution and Genetics Chinese Academy of SciencesKunming 650223China

Next-generation sequencing(NGS),represented by Illumina platforms,has been an essential cornerstone of basic and applied ***,the sequencing error rate of 1 per 1000 bp(10^(−3))represents a serious hurdle for research areas focusing on rare mutations,such as somatic mosaicism or microbe *** examining the high-fidelity sequencing methods developed in the past decade,we summarized three major factors underlying errors and the corresponding 12 strategies mitigating these *** then proposed a novel framework to classify 11 preexisting representative methods according to the corresponding combinatory strategies and identified three trends that emerged during methodological *** further extended this analysis to eight long-read sequencing methods,emphasizing error reduction ***,we suggest two promising future directions that could achieve comparable or even higher accuracy with lower costs in both NGS and long-read sequencing.

关键词： Sequencing error High-fidelity sequencing Consensus sequencing Single-molecule sequencing Rare mutation

Multiple thermal events recorded in the Acasta Gneiss Complex:Evidence from in-situ dating of zircon, titanite, and apatite

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Science China Earth Sciences 2024年第3期67卷 673-686页

作者： Qingfeng MEI Jinhui YANG Jinfeng SUN Qiuli LI Shitou WU Xiaoxiao LING Peng PENG Hao WANG state key laboratory of Lithospheric evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China key laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China

In-situ dating of the zircons, titanites, and apatites in the rock fragments of approximately 1 cm2in size from the Acasta Gneiss Complex was performed using secondary ion mass spectrometry or laser ablation inductively coupled plasma mass spectrometry to provide constraints on the thermal history of the Acasta Gneiss Complex. The zircons in these rock fragments typically exhibit multiple age populations, reflecting the presence of inherited zircons or the post-crystallization process of zircon overgrowth. Combined with previous studies, our zircon dating results reveal multiple magmatic events that occurred in the Acasta Gneiss Complex, specifically at >3.96, ~3.72, and ~3.57 Ga, respectively. A titanite Pb-Pb isochron age of2911±22 Ma(95% confidence level, MSWD=1.5) for sample AY199 is identified, consistent with the timing of the latest Archean magmatism in the Acasta Gneiss Complex. The titanite U-Pb ages for samples AC478 and AY066 are 1932±270 Ma(95% confidence level, MSWD=2.3) and 1813±45 Ma(95% confidence level, MSWD=2.3), respectively. The apatites in sample P090803-C exhibit a Pb-Pb isochron age of 1833±26 Ma(95% confidence level, MSWD=1.4). The apatite U-Pb ages for samples AC478, AY199, and AY066 are 1850±20 Ma(95% confidence level, MSWD=1.3), 1827±100 Ma(95% confidence level, MSWD=6.3), and 1807±58 Ma(95% confidence level, MSWD=3.9), respectively. Titanites in samples AC478 and AY066, as well as the apatites in all four investigated samples, show a uniform age(Pb-Pb or U-Pb age) of ~1.9–1.8 Ga,indicating U-Pb system reset in these minerals due to the Wopmay orogeny and documenting that the peak temperature condition associated with the Wopmay orogeny exceeded the apatite U-Pb closure temperature and approached or exceeded that of titanite.

关键词： Zircon Titanite Apatite Acasta Gneiss Complex Wopmay Orogen

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Revisiting the Mg isotopic systematics of siliciclastic components of sediments and sedimentary rocks:A new geochemical proxy of continental weathering in Earth's history

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Science China Earth Sciences 2024年第2期67卷 620-633页

作者： Tianzheng HUANG Bing SHEN Kangjun HUANG Meng NING Chao LI Jinzhuang XUE Yuanlin SUN Baoqi HUANG key laboratory of Orogenic Belt and Crustal evolution MOESchool of Earth and Space SciencesPeking UniversityBeijing100871China state key laboratory of Continental Dynamics Shaanxi Key Laboratory of Early Life and EnvironmentsDepartment of GeologyNorthwest UniversityXi’an710069China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu610059China key laboratory of Rhenium-Osmium Isotopic Geochemistry Chinese Academy of Geological SciencesBeijing100037China

The Mg isotopic compositions of siliciclastic components(δ^(26)Mg_(sili))of sediments and sedimentary rocks have been commonly used to constrain the intensity of continental weathering,based on observations of,(1)an upward enrichment of26Mg in modern weathering profiles,(2)preferential uptake of26Mg in soil clays,and(3)general positive correlations between weathering intensities andδ^(26)Mg_(sili)***,not all weathering profiles display an upward increase ofδ^(26)Mg_(sili),and not all soil clays enrich in26Mg,complicating the interpretations ofδ^(26)Mg_(sili)data of sediments and sedimentary *** further explore the controls ofδ^(26)Mg_(sili)of sediments and sedimentary rocks,here we measuredδ^(26)Mg_(sili),mineralogical compositions and major element compositions of deep sea sediments from South China Sea(SCS)and carbonate rock samples from two late Paleozoic sections in South *** samples show decreasing trends of both normalized Mg concentration(Mgnorm)andδ^(26)Mg_(sili)values with the increase of weathering intensity,while SCS sediments samples do not show any correlation between Mgnormorδ^(26)Mg_(sili)values and weathering intensity.A three-stages weathering model is developed to explain the observed Mgnorm andδ^(26)Mg_(sili)*** the new model,weathering can be divided into three stages,(1)the preliminary weathering stage characterized by dissolution of primary minerals and formation of secondary clay minerals in saprolite,(2)the transitional stage with massive vermiculite and chlorite formation on the bottom of soil,and(3)the advanced stage showing dissolution of vermiculite and chlorite in the top of *** new model explains anδ^(26)Mg_(sili)increase and Mgnormdecrease with an increase weathering intensity in preliminary weathering stage and decrease of Mgnormandδ^(26)Mg_(sili)with increase weathering intensity in advanced weathering *** revised weathering model warrants the application of Mg isotope in the study of contin

关键词： Clay mineral Chemical weathering CIA Soil Weathering model

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