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Salinity variation and hydrographic dynamics in the early Cambrian Nanhua Basin(South China)

Science China Earth Sciences 2023年第6期66卷 1268-1278页

作者： Meng CHENG Zihu ZHANG chengsheng jin Wei WEI Haiyang WANG Thomas J.ALGEO Chao LI State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation&Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China International Center for Sedimentary Geochemistry and Biogeochemistry Research Chengdu University of TechnologyChengdu 610059China College of Resource Environment and Tourism Hubei University of Arts and ScienceXiangyang 441053China School of Earth Science China University of GeosciencesWuhan 430074China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China Department of Geology University of CincinnatiCincinnati 45221-0013USA

Despite intensive study of the early Cambrian Nanhua Basin(ECNB)in South China,its degree of connectedness to the open ocean remains uncertain,impeding analysis of contemporaneous oceanic redox evolution and its role in the Cambrian *** analyzed bulk-shale B/Ga,a newly proposed proxy for watermass salinity in ancient depositional systems,for three sections(Daotuo,Yuanjia,and Zhalagou)representing a range of water depths in the ECNB and spanning early Cambrian Stages 2 and *** B/Ga proxy records a salinity gradient in the basin,with increasing salinity from shallow-to deep-water areas,particularly during the deposition of black shales of the lower Jiumenchong/Niutitang/Zhalagou *** gradient was probably due to the mixing of freshwater from adjacent landmasses with marine waters within a moderately restricted *** three study sections exhibit a monotonic rise in salinity over the~9-Myr study interval,reflecting increased watermass exchange with the open ocean due to regional tectonic and/or global sea-level *** improved watermass exchange may have weakened water-column stratification and reduced deep-water anoxia in the ECNB,contributing the enhanced oceanic oxygenation along with global environmental controls and further modulating the expression of the Cambrian Explosion recorded in Lower Cambrian sections of South *** study thus highlights the need for comprehensive analyses of hydrographic dynamics in marginal-marine settings that are used to explore co-evolutionary relationships between early animals and environmental oxygen levels.

关键词： B/Ga Boron Gallium Watermass restriction Cambrian Explosion Co-evolution

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Soil pH impact on microbial tetraether lipids and terrestrial input index (BIT) in China

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Science China Earth Sciences 2012年第2期55卷 236-245页

作者： YANG Huan DING WeiHua WANG jinXiang jin chengsheng HE GangQiang QIN YangMin XIE ShuCheng State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China

The distributions of microbial tetraether lipids i.e. glycerol dialkyl glycerol tetraethers (GDGTs) were investigated in a variety of Chinese soils featured by a wide range of pH values in different climate zones. The bacterial branched GDGTs and archaeal isoprenoid GDGTs were found to be widely distributed in Chinese soils and their relative abundance was controlled primarily by soil pH. The bacterial bGDGTs usually dominate over archaeal iGDGTs in abundance when the soil pH is below 8.0. However archaeal iGDGTs become dominant and the abundance of halophilic archaea characterized by GDGT V without cyclopentyl ring increases dramatically in the alkaline soil with pH greater than 8.0. The relative abundance of archaeal iGDGTs to bacterial bGDGTs was defined here as RAI index. The RAI index decreases with elevated soil pH and a linear correlation is found between them indicating that the relative abundance of archaeal iGDGTs to bacterial bGDGTs increases with increased pH. The RAI index thus could be a novel proxy of the pH values of paleosol. The terrestrial input index BIT (Branched and Isoprenoid Tetraethers Index) decreases with increased soil pH suggesting that soil pH should be taken into consideration when the terrestrial contribution to marine sediments is estimated by BIT index. Moreover the TEX86 index cannot be used to reconstruct sea surface temperature in the sediments featured by a large terrestrial input.

关键词： GDGTs Archaea BIT index soil pH

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Spatiotemporal variability of ocean chemistry in the early Cambrian,South China

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Science China Earth Sciences 2014年第4期57卷 579-591页

作者： jin chengsheng LI Chao PENG XingFang CUI Hao SHI Wei ZHANG ZiHu LUO GenMing XIE ShuCheng State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

Following the Ediacaran metazoan radiation,the "Cambrian Explosion" set up the major framework of todays' animal phyla as well as modern marine ***,we present a preliminary investigation on the temporal and spatial(from shallow to deep waters) variations of the early Cambrian ocean chemistry in South China through analyzing a Fe-S-C systematic dataset integrated from *** investigation indicates that the early Cambrian deep ocean in South China was still anoxic and Fe2+-enriched(i.e.,ferruginous) although its surface was oxic,and in between a metastable euxinic(anoxic and sulfidic) water zone may have dynamically developed in anoxic shelf waters with an increasing weathering sulfate ***,accompanying marine transgression and regression cycles in the early Cambrian,such a "sandwich" structure in ocean redox chemistry demonstrates five evolutional stages,which can be well correlated to the spatiotemporal patterns of fossil records in South *** good correlation between metazoan fossil occurrences and water chemistry in South China suggests that early animals possibly possessed ability to inhabit anoxic but generally not euxinic environments as free H2S was fatal to most *** view can well explain why those small shell fauna and sponges disappeared from shelf to slope areas where sulfidic Ni-Mo-rich shales were widely ***,we conclude that the spatiotemporal variations of ocean chemistry and its biological effects probably played a key role in the phased animal radiations and "extinctions" in the early Cambrian.

关键词： South China early Cambrian ocean chemistry euxinic Cambrian Explosion

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The redox structure of Ediacaran and early Cambrian oceans and its controls

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Science Bulletin 2020年第24期65卷 2141-2149,M0006页

作者： Chao Li Wei Shi Meng Cheng chengsheng jin Thomas J.Algeo State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China Yunnan Key Laboratory for Palaeobiology Yunnan UniversityKunming 650091China State Key Laboratory of Geological Process and Mineral Resources China University of GeosciencesWuhan 430074China Department of Geology University of CincinnatiCincinnati 0H45221USA

The rapid diversification of early animals during the Ediacaran(635–541 Ma) and early Cambrian(ca.541–509 Ma) has frequently been attributed to increasing oceanic oxygenation. However, the pattern of oceanic oxygenation and its relationship to early animal evolution remain in debate. In this review,we examine the redox structure of Ediacaran and early Cambrian oceans and its controls, offering new insights into contemporaneous oceanic oxygenation patterns and their role in the coevolution of environments and early animals. We review the development of marine redox models which, in combination with independent distal deep-ocean redox proxies, supports a highly redox-stratified shelf and an anoxia-dominated deep ocean during the Ediacaran and early Cambrian. Geochemical and modeling evidence indicates that the marine redox structure was likely controlled by low atmospheric O2 levels and low seawater vertical mixing rates on shelves at that time. Furthermore, theoretical analysis and increasing geochemical evidence, particularly from South China, show that limited sulfate availability was a primary control on the attenuation of mid-depth euxinia offshore, in contrast to the existing paradigm invoking decreased organic carbon fluxes distally. In light of our review, we infer that if oceanic oxygenation indeed triggered the rise of early animals, it must have done so through a shelf oxygenation which was probably driven by elevated oxidant availability. Our review calls for further studies on EdiacaranCambrian marine redox structure and its controls, particularly from regions outside of South China, in order to better understand the coevolutionary relationship between oceanic redox and early animals.

关键词： Redox stratification Oceanic oxygenation Euxinia Early animal Cambrian Explosion

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云南昆明寒武纪早期浅水相磷块岩的氧化还原环境及成因机制

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地质学报 2021年第12期95卷 3858-3868页

作者：杨兵金承胜刘欣韦一中国地质调查局自然资源实物地质资料中心河北廊坊065201 云南大学古生物重点实验室古生物研究院云南昆明650091 中国地质调查局沈阳地质矿产研究所辽宁沈阳110034 华北科技学院安全工程学院河北廊坊065201

磷是重要的营养元素,与古环境和生命演化密切相关。在埃迪卡拉纪—寒武纪之交,伴随着骨骼化动物的辐射,华南甚至全球广泛沉积了大量磷酸盐,这暗示磷是古环境的变化与生命演化之间关系的桥梁。然而,目前,磷块岩的沉积环境和形成机制尚不... 详细信息

磷是重要的营养元素,与古环境和生命演化密切相关。在埃迪卡拉纪—寒武纪之交,伴随着骨骼化动物的辐射,华南甚至全球广泛沉积了大量磷酸盐,这暗示磷是古环境的变化与生命演化之间关系的桥梁。然而,目前,磷块岩的沉积环境和形成机制尚不明确。为探究磷酸盐富集的沉积环境和形成机理,本文研究了华南寒武纪早期梅树村剖面磷块岩的磷酸盐聚集形式、黄铁矿形态学和稀土元素。磷块岩主要是由结晶氟磷酸钙、隐晶质氟磷酸钙和铁氧化物组成。稀土配分模式均为"帽型"配分模式,与沉积物中铁-锰还原带之中的稀土配分模式类似,表明稀土元素遭受了早期成岩的影响。磷块岩中没有草莓状黄铁矿和较低的Ce负异常(Ce/Ce^(*)=0.50~0.82,平均值为0.70),暗示磷块岩沉积于氧化/次氧化的沉积环境。Eu元素未发生异常(Eu/Eu^(*)=0.92~1.08,平均值为0.98),暗示磷块岩可能未受到热液作用的影响。较高的Y/Ho比值(55.3~74.5,平均值为63.6),与海水Y/Ho比值相似,表明磷块岩来源于海水。鉴于华南寒武纪早期广泛的氧化事件、缺氧分层的海水化学结构和上升流活动,本文认为磷块岩的形成源于氧化背景下较高的磷酸盐浓度和深部还原环境中的磷酸盐随上升流活动携带至氧化-次氧化浅水区域。

关键词：结晶氟磷酸钙磷块岩稀土元素氧化还原状态扬子地台

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华南寒武纪早期海水氧化还原状态对动物演化的影响

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地球科学 2024年第10期49卷 3674-3684页

作者：金承胜崔豪程猛张子虎常华进张弢曹正琦湖北文理学院资源环境与旅游学院湖北襄阳441053 长江水利委员会长江科学院湖北武汉430010 成都理工大学沉积地质研究院四川成都610059

寒武纪早期海洋氧化还原状态的变化经常被用来解释早期动物的辐射和灭绝,但该机制目前并不十分清晰.对华南盆地相渣拉沟剖面开展了总有机碳含量、铁组分、主量元素和微量元素的研究.在此基础之上,将渣拉沟剖面的海水氧化还原状态与华南... 详细信息

寒武纪早期海洋氧化还原状态的变化经常被用来解释早期动物的辐射和灭绝,但该机制目前并不十分清晰.对华南盆地相渣拉沟剖面开展了总有机碳含量、铁组分、主量元素和微量元素的研究.在此基础之上,将渣拉沟剖面的海水氧化还原状态与华南和西伯利亚其他剖面已发表的研究结果进行了综合对比分析.结果表明,寒武纪第二期至第三期出现了氧化水体的扩张,而寒武纪第四期海洋变得更加缺氧.寒武纪早期海洋氧化还原状态与化石记录之间的对比研究表明,寒武纪第三期海洋氧化程度的增加可能是早期动物辐射的关键因素,而寒武纪第四期海洋缺氧程度的加剧可能是早期动物多样性降低和古杯动物灭绝的直接原因.

关键词：铁组分微量元素缺氧动物灭绝扬子陆块地球化学

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Enhanced solid-electrolyte interface efficiency for practically viable hydrogen-air fuel cell systems

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Journal of Energy Chemistry 2025年第1期100卷 356-368页

作者： Venkitesan Sakthivel Dong jin Yoo Graduate School Department of Energy Storage/Conversion Engineering (BK21 FOUR) Hydrogen and Fuel Cell Research Center Jeonbuk National University Jeonju Department of Life Science Jeonbuk National University

Proton exchange membrane fuel cells （PEMFCs） provide an appealing sustainable energy system,with the solid-electrolyte membrane playing a crucial role in its overall ***,sulfonated poly（1,4-phenylene ether-ether sulfone）(SPEES),an aromatic hydrocarbon polymer,has garnered considerable attention as an alternative to Nafion ***,the long-term durability and stability of SPEES present a significant *** this context,we introduce a potential solution in the form of an additive,specifically a core–shell-based amine-functionalized iron titanate （A–Fe2TiO5）,which holds promise for improving the lifetime,proton conductivity,and power density of SPEES in *** modified SPEES/A–Fe2TiO5composite membranes exhibited notable characteristics,including high water uptake,enhanced thermomechanical stability,and oxidative ***,the SPEES membrane loaded with 1.2 wt%of A–Fe2TiO5demonstrates a maximum proton conductivity of 155 mS cm-1,a twofold increase compared to the SPEES membrane,at 80°C under 100%relative humidity （RH）.Furthermore,the 1.2 wt%of A–Fe2TiO5/SPEES composite membranes exhibited a maximum power density of 397.37 mW cm-2and a current density of 1148 mA cm-2at 60°C under 100%RH,with an opencircuit voltage decay of 0.05 m V/h during 103 h of continuous *** study offers significant insights into the development and understanding of innovative SPEES nanocomposite membranes for PEMFC applications.

关键词： Composite membranes

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Late Paleozoic to early Mesozoic volcanic-sedimentary history of the southeastern margin of the Central Asian Orogenic Belt: Timing of uplift of the Inner Mongolia paleo-uplift

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Science China Earth Sciences 2025年第1期68卷 297-309页

作者： Wenxing HAO jin-Hui YANG Guang ZHU State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences School of Resource and Environmental Engineering Hefei University of Technology

The Kulun region is located in the eastern Bainaimiao arc belt on the southeastern margin of the Central Asian Orogenic Belt(CAOB), adjacent to the North China Craton(NCC) to the south. This region records the closure of the PaleoAsian Ocean during the Paleozoic to early Mesozoic and is key to study the tectonic evolution of the northern margin of the *** conducted zircon U-Pb geochronology and Hf isotope analysis of volcanic-sedimentary and intrusive rocks in the Kulun region. The volcanic-sedimentary rocks were previously assigned an early Carboniferous age, but include volcanic rocks with ages of 267–266 Ma and sedimentary rocks with youngest detrital zircon age peaks of 265–244 Ma, which were intruded by a granite with an age of 242 Ma. This indicates that these rocks are actually middle Permian to Middle Triassic in age(267–242Ma) and correspond to the Qingfengshan and Liujiagou formations. Moreover, two volcanic rock samples have high εHf(t) values(+1.6 to +16.1) and relatively young two-stage Hf model ages(1095–327 Ma), indicating their sources associated with the CAOB. The age spectra and Hf isotopic characteristics of detrital zircons from the sedimentary rocks suggest that, during the middle Permian to Middle Triassic, the sedimentary provenance in the Kulun region was mainly the CAOB. However, by the Early Jurassic, the provenance changed to the NCC(i.e., the Inner Mongolia Paleo-uplift, IMPU). This result, combined with the development of a series of conglomerates on the northern margin of the NCC in the Late Triassic(i.e., Xingshikou, Xiaoyingzi,and Xiaohekou formations), indicates the Kulun region experienced an abrupt change in paleogeography during the Late Triassic, with the IMPU undergoing significant uplift and thus becoming the main sediment source in the Kulun region. Based on the Late Triassic alkaline igneous belt(235–215 Ma) in the IMPU, we speculate that this uplift was caused by detachment of the southward-subducting Paleo-Asian oceanic

关键词： Central Asian Orogenic Belt the North China Craton Zircon geochronology Hf isotopes Inner Mongolia Paleo-uplift

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Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai Li Zhen Ma jin-Hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

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Fibrinogen’s potential role in connecting cerebrovascular abnormalities with glymphatic dysfunction in Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 203-204页

作者： Vishal Singh Arnab Choudhury Hyung jin Ahn Department of Pharmacology Physiology and NeurosciencesRutgers-New Jersey Medical SchoolNewarkNJUSA Brain Health Institute Rutgers UniversityPiscatawayNJUSA

Alzheimer’s disease(AD)stands out as the primary manifestation of age-related dementia,portraying a chronic neurodegenerative disorder distinguished by the accumulation of fibrillar amyloid-β(Aβ)plaques and neurofibrillary tangles of hyperphosphorylated ***,from a clinical standpoint,AD presents itself as a complex condition with a spectrum of dysfunctions rather than a singular pathological *** often-overlooked aspect of the disease is the presence of extensive cerebrovascular abnormalities,given that the majority of AD patients experience altered cerebral blood flow,damaged vasculature,increased microinfarcts and *** models of AD further support this observation,showing cerebrovascular dysfunction such as impaired cerebral blood flow and altered cerebrovascular reactivity(Tataryn et al.,2021;Gareau et al.,2023).

关键词： cerebrovascular dysfunction Alzheimer

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