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spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

National science Review 2024年第2期11卷 155-167页

作者： Peng He Meng-Yang Hu Jin-Hong Li Tian-Zhang Qiao Yi-Lin Lu shou-Fei Zhu Frontiers science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

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Unveiling Nb-Ta mineralization processes:Insight from quartz textural and chemical characteristics in the songshugang deposit,Jiangxi Province,south China

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Acta Geochimica 2024年第4期43卷 737-753页

作者： Hengsong Zhang shaohao Zou Xilian Chen Deru Xu Zhilin Wang Yongwen Zhang Hua Wang state key laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013JiangxiChina school of earth sciences East China University of TechnologyNanchang 330013JiangxiChina key laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Jiangxi Mineral Resources Guarantee and service Center Nanchang 330025JiangxiChina

The songshugang deposit is a large Ta-Nb deposit in south China,with Ta-Nb mineralization associated genetically with the granite and pegmatite.A diversity of quartz from topaz-albite granite,quartz-mica pegmatite,quartz-feldspar pegmatite,and quartz-fluorite pegmatite at songshugang was studied by CL and LA-ICP-Ms in order to constrain enrichment mechanisms of Nb and Ta and to find geochemical indicators of quartz for rare metal *** image illuminates a canvas of complexity,the quartz from topaz-albite granite,quartz-mica pegmatite,quartz-feldspar pegmatite,and quartz-fluorite pegmatite,exhibits numerous dark CL streaks,patches,and a series of healed *** textures suggest that the rocks were fractured because of deep crustal pressure,and underwent later hydrothermal metasomatism and quartz *** quartz from quartz-fluorite pegmatite present limited patches or fractures but distinct growth bands,indicating that the melt fluid composition during the formation of quartz at this stage varies greatly and is less aff ected by mechanical *** LA-ICP-Ms analysis of quartz shows that there is a positive correlation between Al and Li in the quartz from topaz-albite granite,quartz-mica pegmatite,quartz-feldspar pegmatite,to quartz-fluorite pegmatite,indicating that Al mainly enters the quartz lattice through charge compensation substitution mechanism with ***,our data deviate from the theoretical Li:Al mass ratio of~1:3.89 in quartz,indicating that there may be competition between H^(+)and Li in a water-rich magmatic *** quartz from topaz-albite granite is enriched in K and Na elements,and the quartz from quartz-fluorite pegmatite is enriched in fluorite with a low Ca content in quartz,further elucidating that these rocks were subjected to hydrothermal *** topaz-albitite granite to quartz-fluorite pegmatite,Al,Li and Ge content and Al/Ti,Ge/Ti,sb/Ti ratios in quartz gradually increased,but

关键词： Nb-Ta deposit Quartz Cathodoluminescence LA-ICP-Ms Trace elements Magma-hydrothermal evolution

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Reverse metasomatism of subduction zone fluids

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science China earth sciences 2024年第2期67卷 634-638页

作者： Yixiang CHEN school of earth and space sciences University of Science and Technology of ChinaHefei 230026China key laboratory of Crust-Mantle Materials and Environments Chinese Academy of SciencesHefei 230026China Center of Excellence for Comparative Planetology Chinese Academy of SciencesHefei 230026China

*** metasomatism in subduction zones subduction zones are the key tectonic setting that links earth's surficial sphere to deep sphere(Zheng and Chen,2016).Fluid action occurring in subduction zones is closely related to many important geological processes such as volcanic and seismic activity,the migration,enrichment and mineralization of metallogenic elements,mass transport and crust-mantle material cycling,and the evolution of earth's surface ***,it is of great significance to study the sources,properties and geochemical effects of subduction zone fluids(Zheng,2019).

关键词： subduction metasomatism earth

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Quantitative assessment of the complexity of geological structures in terms of seismic propagators

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science China earth sciences 2010年第1期53卷 54-63页

作者： FU LiYun key laboratory of the earth’s deep interior,Institute of Geology and Geophysics,Chinese Academy of sciences,Beijing 100029,China key laboratory of the earth’s deep interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

How a wave interacts with heterogeneous media has been pursued by many *** complexity of subsurface heterogeneities is seismologically a relative concept to wavelengths of seismic waves.A growing perception is that velocity variations,propagation angles,and computational accuracies are closely related at a variety of scales.A tentative strategy to quantitatively evaluate the complexity of subsurface heterogeneous media is presented in this article to see what scales of geological heterogeneities to be captured by *** express complex subsurface structures as the slowness-and angularheterogeneity spectra to quantify velocity contrasts and dipping-angle distributions of complex geological *** the other hand,the scaling characteristics of a propagator are measured through dispersion analysis by its angular spectra plotted against refractive indexes and propagation angles,respectively.A parameter termed as imaging efficiency is introduced by associating the geological heterogeneity spectra with the propagator's angular spectra to understand the coherent interference between the medium's heterogeneity and the propagator's scaling ***,a complexity coefficient can be defined to evaluate geological complexities in terms of *** application of this strategy is demonstrated to the sEG/EAEG salt model.

关键词： geological heterogeneity spectra seismic imaging propagator’s angular spectra imaging efficiency complexity coefficient

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地球演化历史中氧逸度变化对壳幔循环启动、风化和超大陆循环的指示（英文）

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science Bulletin 2024年第1期 97-102页

作者：王瑞邬绍宸 Roberto F.Weinberg William J.Collins Peter A.Cawood state key laboratory of Geological Processes and Mineral Resources Institute of Earth Sciences China University of Geosciences Frontiers science Center for deep-time Digital earth China University of Geosciences (Beijing) school of earth Atmosphere and Environment Monash University The Institute for Geoscience Research Curtin University

We apply a zircon redox index to a global compilation of detrital zircons to track the variation of oxidation state, expressed as ΔFMQ, through earth’s history. Those from I-type rocks, which comprise mantle and crustal igneous protoliths, including tonalite–trondhjemite–granodiorites(TTGs), generally have a high oxidation state(ΔFMQ > 0). In contrast, zircons from igneous rocks derived from supracrustal source rocks(s-type) are commonly reduced(ΔFMQ sity function derived from the Gaussian-Kernel-Density-Estimation, we use the maximum likelihood estimation(MLE) to distinguish stype from I-type zircons through earth’s history using zircon redox. Voluminous s-type magma production shows a ca. 600 Ma cyclicity that is closely related to the supercontinent cycle. We link a cyclic drop in redox values after 2.6 Ga to periodic s-type magma generation associated with burial and melting of metasedimentary rocks during supercontinent assembly and amalgamation. The ΔFMQ of the detrital zircons rise at ～3.5 Ga followed by a consistent average ΔFMQ > 0 over the last 3 Ga. Given that the redox state of magmas is independent of crustal thickness and silica variation, and elevated values are likely more closely related to tectonic setting, we suggest that the consistent average ΔFMQ > 0 from ca.3.5 Ga onwards relates to recycling of oceanic lithosphere back into the mantle in what eventually became established as subduction zones. The more reduced magmas associated with sedimentary sources, became established at 2.6 Ga, presumably in response to continental rocks rising above sealevel, and follow peaks of productivity associated with the supercontinent cycle.

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The origin and evolution of earth's nitrogen

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National science Review 2024年第6期11卷 56-75页

作者： Yuan Li state key laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Bayerisches Geoinstitut Universit?t Bayreuth

Nitrogen is a vital element for life on earth. Its cycling between the surface(atmosphere + crust) and the mantle has a profound influence on the atmosphere and climate. However, our understanding of the origin and evolution of earth's nitrogen is still incomplete. This review presents an overview of the current understanding of earth's nitrogen budget and the isotope composition of different reservoirs, laboratory constraints on deep nitrogen geochemistry, and our understanding of the origin of earth's nitrogen and the deep nitrogen cycle through plate subduction and volcanism. The earth may have acquired its nitrogen heterogeneously during the main accretion phase, initially from reduced, enstatite-chondrite-like impactors,and subsequently from increasingly oxidized impactors and minimal CI-chondrite-like materials. Like earth's surface, the mantle and core are also significant nitrogen reservoirs. The nitrogen abundance and isotope composition of these three reservoirs may have been fundamentally established during the main accretion phase and have been insignificantly modified afterwards by the deep nitrogen cycle, although there is a net nitrogen ingassing into earth's mantle in modern subduction zones. However, it is estimated that the early atmosphere of earth may have contained ～1.4 times the present-day atmospheric nitrogen(PAN),with ～0.4 PAN being sequestered into the crust via biotic nitrogen fixation. In order to gain a better understanding of the origin and evolution of earth's nitrogen, directions for future research are suggested.

关键词： nitrogen isotopes silicate earth atmosphere magma ocean

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Fluid-rock interaction experiments with andesite at 100℃ for potential carbon storage in geothermal reservoirs

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deep Underground science and Engineering 2024年第3期3卷 369-382页

作者： Grace E.Belshaw Elisabeth steer Yukun Ji Herwin Azis Benyamin sapiie Bagus Muljadi Veerle Vandeginste school of Chemistry University of NottinghamNottinghamUK GeoEnergy Research Centre University of NottinghamNottinghamUK British Geological survey KeyworthUK state key laboratory of Intelligent Construction and Healthy Operation and Maintenance of deep Underground Engineering China University of Mining and TechnologyXuzhouChina PT supreme Energy JakartaIndonesia Faculty of earth sciences and Technology Institut Teknologi BandungBandungIndonesia Faculty of Engineering University of NottinghamNottinghamUK Department of Materials Engineering KU LeuvenCampus BrugesBrugesBelgium

Geothermal energy extraction often results in the release of naturally occurring carbon dioxide(CO_(2))as a *** on carbon storage using volcanic rock types other than basalt under both acidic and elevated temperature conditions has been limited so *** study uses batch reactor experiments at 100℃ to investigate the dissolution of andesite rock samples obtained from an active geothermal reservoir in sumatra(Indonesia).The samples are subjected to reactions with neutral-pH fluids and acidic fluids,mimicking the geochemical responses upon reinjection of geothermal fluids,either without or with dissolved acidic gases,*** elemental analysis reveals the release of Ca^(2+)ions into the fluids through the dissolution of *** overall dissolution rate of the rock samples is 2.4×10^(–11)to 4.2×10^(–11)mol/(m^(2)·s),based on the si release during the initial 7 h of the *** dissolution rates are about two orders of magnitude lower than those reported for basaltic rocks under similar reaction *** study offers valuable insights into the potential utilization of andesite reservoirs for effective CO_(2) storage via mineralization.

关键词： andesite carbon sequestration geothermal reservoirs plagioclase dissolution

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Incorporating mesopelagic fish into the evaluation of conservation areas for marine living resources under climate change scenarios

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Marine Life science & Technology 2024年第2期6卷 68-83页

作者： shuhao Liu Yang Liu Katharina Teschke Mark AHindell Rachel Downey Briannyn Woods Bin Kang shuyang Ma Chi Zhang Jianchao Li Zhenjiang Ye Peng sun Jianfeng He Yongjun Tian Research Centre for deep sea and Polar Fisheries and Key Laboratory of MaricultureMinistry of EducationOcean University of ChinaQingdao 266003China Frontiers science Center for deep Ocean Multispheres and earth system Ocean University of ChinaQingdao 266100China Alfred Wegener Institute Helmholtz Centre for Polar and Marine ResearchAm Handelshafen 1227570 BremerhavenGermany Helmholtz Institute for Functional Marine Biodiversity at the University Oldenburg Ammerländer Heerstraße 23123129 OldenburgGermany Institute for Marine and Antarctic studies University of TasmaniaHobart 7004Australia Fenner school of Environment and society Australian National UniversityCanberraACT 2602Australia College of Fisheries Ocean University of ChinaQingdao 266003China Polar Research Institute of China Shanghai 200136China

Mesopelagic fish(meso-fish)are central species within the southern Ocean(sO).However,their ecosystem role and adaptive capacity to climate change are rarely integrated into protected areas *** is a pity given their importance as crucial prey and predators in food webs,coupled with the impacts of climate ***,we estimate the habitat distribution of nine meso-fish using an ensemble model approach(MAXENT,random forest,and boosted regression tree).Four climate model simulations were used to project their distribution under two representative concentration pathways(RCP4.5 and RCP8.5)for short-term(2006–2055)and long-term(2050–2099)*** addition,we assess the ecological representativeness of protected areas under climate change scenarios using meso-fish as indicator *** models show that all species shift poleward in the ***(family Myctophidae)are predicted to migrate poleward more than other families(Paralepididae,Nototheniidae,Bathylagidae,and Gonostomatidae).In comparison,lanternfishes were projected to increase habitat area in the eastern sO but lose area in the western sO;the opposite was projected for species in other *** areas(IAs)of meso-fish are mainly distributed near the Antarctic Peninsula and East *** protected area cover 23% of IAs at present and 38%of IAs in the future(RCP8.5,long-term future).Many IAs of meso-fish still need to be included in protected areas,such as the Prydz Bay and the seas around the Antarctic *** results provide a framework for evaluating protected areas incorporating climate change adaptation strategies for protected areas management.

关键词： Myctophids Mesopelagic fish species distribution model southern Ocean Antarctic Peninsula

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Identification of the Caroline Plate boundary:constraints from magnetic anomaly

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Acta Oceanologica sinica 2024年第8期43卷 1-12页

作者： Yongtao Fu Guoliang Zhang Wanyin Wang An Yang Tao He Zhangguo Zhou Xiao Han key laboratory of Ocean Observation and Forecasting/key laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China National Engineering Research Center for Offshore Oil and Gas Exploration Beijing 100028China laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Center of deep sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China Institute of Gravity and Magnetic Technology Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of EducationSchool of Geology Engineering and GeomaticsChang’an UniversityXi’an 710054China University of Chinese Academy of sciences Beijing 100049China

The Caroline Plate is located among the Pacific Plate,the Philippine sea Plate,and the India Australia Plate,and plays a key role in controlling the spreading direction of the Philippine sea *** Caroline submarine Plateau(or Caroline Ridge)and the Eauripik Rise on the south formed a remarkable T-shaped large igneous rock province,which covered the northern boundary between the Caroline Plate and the Pacific ***,relationship between these tectonic units and magma evolution remains *** on magnetic data from the earth Magnetic Anomaly Grid(2-arc-minute resolution)(V2),the normalized vertical derivative of the total horizontal derivative(NVDR-THDR)technique was used to study the boundary of the Caroline *** show that the northern boundary is a transform fault that runs 1400 km long in approximately 28 km wide along the N8°in E-W *** eastern boundary is an NNW-ssE trending fault zone and subduction zone with a width of tens to hundreds of kilometers;and the north of N4°is a fracture zone of dense *** southeastern boundary may be the Lyra *** area between the southwestern part of the Caroline Plate and the Ayu Trough is occupied by a wide shear zone up to 100 km wide in nearly s-N trending in *** Eauripik transform fault(ETF)in the center of the Caroline Plate and the fault zones in the east and west basins are mostly semi-parallel sinistral NNW-ssE–trending faults,which together with the eastern boundary Mussau Trench(MT)sinistral fault,the northern Caroline transform fault(CTF),and the southern shear zone of the western boundary,indicates the sinistral characteristics of the Caroline *** Caroline hotspot erupted in the Pacific Plate near the CTF and formed the west Caroline Ridge,and then joined with the Caroline transform fault at the N8°.A large amount of magma erupted along the CTF,by which the east Caroline Ridge was *** the same time,a large amount of magma developed southward via the e

关键词： Caroline Plate magnetic anomaly normalized vertical derivative of the total horizontal derivative plate boundary Caroline Ridge Eauripik Rise

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Comparative Orotomy of the Archean superior, North China, and Phanerozoic Altaid Orogenic systems Architecture

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Acta Geologica sinica(English Edition) 2024年第S1期 33-35页

作者： T.M.KUsKY A.M.C.?ENG?R Center for Global Tectonics School of Earth Sciences and State Key Laboratory for Geological Processes and Mineral Resources China University of Geosciences Eurasia Institute of earth sciences Istanbul Technical University Department of Geology Faculty of Mines Istanbul Technical University

Geological maps encode vast amounts of data about rock types, ages, chemistry, orogenic architecture and deep-time history or different tectonic units, yet these are often difficult to extract because of the way different geologists portray their results at various scales. To understand orogenesis in 4D, it is essential to uniformly integrate map data, together with geophysical data and deep geochemical mapping(Wang et al., 2023).

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