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Carbon cycle variability in tropical Atlantic across two Early Eocene hyperthermals

Geoscience Frontiers 2021年第2期12卷 521-530页

作者： Shijun Jiang Ying Cui yasu wang Institute of Groundwater and Earth Sciences Jinan UniversityGuangzhou510632China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519082China Department of Earth and Environmental Studies Montclair State UniversityMontclairNJ07043USA

Early Eocene hyperthermals are geologically short-lived global warming events and represent fundamental perturbations to the global carbon cycle and the Earth’s ecosystem due to massive additions of isotopically light carbon to the ocean-atmosphere *** serve as ancient analogs for understanding how the oceanic carbonate system and surface-ocean ecosystem would respond to ongoing and future climate ***,we present a continuous carbonate record across the Eocene Thermal Maximum 2(ETM2 or H1,ca.54.1 Ma)and H2(ca.54 Ma)events from an expanded section at Ocean Drilling Program Site 1258 in tropical *** abundant calcareous nannofossils and moderate carbonate content throughout the studied interval suggest this record was deposited above the calcite compensation depth(CCD),but below the lysocline and under the influence of terrestrial *** Earth system model cGENIE is used to simulate the carbon cycle dynamics across the ETM2 and H2 to offer insights on the mechanism of the rapid warming and subsequent recovery in climate and *** model suggests moderate changes in ocean pH(0.1–0.2 unit)for the two scenarios,biogenic methane from a rechargeable methane capacitor and organic matter oxidation from thawing of the *** pH changes are consistent with a recent independent pH estimate across the ETM2 using boron *** carbon emission flux during the ETM2 is at least an order of magnitude smaller than that during the Paleocene–Eocene Thermal Maximum(PETM)(0.015–0.05 Pg C yr^(-1)vs.0.3–1.7 Pg C yr^(-1)).The comparable pre-and post-event carbonate contents suggest the lysocline did not over deepen following the ETM2 at this tropical Atlantic site,indicating spatial heterogeneity in the carbonate system due to strong dilution influence from terrestrial weathering and riverine discharge at Site 1258.

关键词： Early Eocene hyperthermals Oceanic carbonate system Stable carbon and oxygen isotopes Earth system modeling Tropical Atlantic cGENIE

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Cretaceous integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1229-1289页

作者： Dangpeng XI Guobiao LI Shijun JIANG Xin RAO Tian JIANG Tianyang wang Zuohuan QIN yasu wang Jianzhong JIA Muhammad KAMRAN Zhongye SHI Yuyang WU Panxi wang Lixin SUN Qinggao ZENG Xiaoqiao WAN State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China College of Oceanography Hohai UniversityNanjing 213200China Key Laboratory of Palaeobiology and Petroleum Stratigraphy Nanjing Institute of Geology and PaleontologyChinese Academy of SciencesNanjing 210008China State Key Laboratory of Tibetan Plateau Earth System Environmentand Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China China National Offshore Oil Corporation Limited Beijing 100028China Shanghai Science and Technology Museum Shanghai 200120China Xizang Bureau of Geological and Mineral Exploration and Development Lhasa 850000China Tianjin Geological Survey Center of China Geological Survey Tianjin 300170China

The Cretaceous Period is a vital time interval in deciphering the evolutionary history of the Neo-Tethys Ocean and the convergence of different plates and blocks across the Qinghai-Tibetan Plateau.A detailed stratigraphic framework and paleogeographic patterns are the basis for understanding the evolution of the Neo-Tethys Ocean and the formation of the QinghaiTibetan ***,the Cretaceous stratigraphy,biota,paleogeography,and major geological events in the Qinghai-Tibetan Plateau are analyzed to establish an integrative stratigraphic framework,reconstruct the paleogeography during the Cretaceous Period,and decode the history of the major geological *** Cretaceous rocks of the Qinghai-Tibetan Plateau and its surrounding area are predominantly marine deposits,with a small amount of interbedded marine-terrestrial and terrestrial *** Indus-Yarlung Tsangpo Suture Zone was responsible for the deposition of deep marine sediments dominated by ophiolite suites and radiolarian *** the south,the Tethys Himalayas and Indus Basin received marine sediments of varying depths and lithology;to the north,the Xigaze and Ladakh forearc basins are also filled with marine *** Lhasa Block,Karakorum Block,western Tarim Basin,and West Burma block consist of shallow marine,interbedded marine-terrestrial,and terrestrial *** Qiangtang Basin and other areas are dominated by terrestrial *** Cretaceous strata of the Qinghai-Tibetan Plateau and its surrounding areas are widely distributed and diversified,with abundant foraminifera,calcareous nannofossils,radiolarians,ammonites,bivalves,and *** the basis of integrated lithostratigraphic,biostratigraphic,geochronologic,and chemostratigraphic analyses,we proposed herein a comprehensive stratigraphic framework for the Cretaceous Period of the eastern *** analyzing the Cretaceous biota of different biogeographic zones from eastern Neo-Tethys and its surrounding a

关键词： Qinghai-Tibetan Plateau Tethys Cretaceous Stratigraphy Biota Paleogeography

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Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第01期 241-248页

作者： Ziqiang wang yasu Chen Jie Li Chen Zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials ScienceSoochow University Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

We report a novel cyano migration-mediated radical-polar crossover process, whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently achieved. This transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic conditions. Mechanistic studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution, leading to the formation of the cyclopropane derivatives.

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背部减振器安装位置优化研究

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现代雷达 2015年第1期37卷 70-73页

作者：余慧杰王亚苏上海理工大学机械工程学院上海200093

针对电子机柜背部减振系统无法避免耦合振动的情况,对背部减振器的安装位置进行优化。文中通过建立理论模型,分析其弯矩和挠度,确定背部减振器安装的最佳位置。所得到的理论结果和实践结果相一致,从而为实践应用提供理论依据,并进一步... 详细信息

针对电子机柜背部减振系统无法避免耦合振动的情况,对背部减振器的安装位置进行优化。文中通过建立理论模型,分析其弯矩和挠度,确定背部减振器安装的最佳位置。所得到的理论结果和实践结果相一致,从而为实践应用提供理论依据,并进一步指导实践应用,尽可能地减小振动带来的有害影响。

关键词：背部减振器安装位置理论模型参数优化

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金属橡胶静刚度特性及其力学模型研究

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中国机械工程 2016年第23期27卷 3167-3171页

作者：余慧杰刘文慧王亚苏上海理工大学上海200093

对金属橡胶成形机理和静刚度特性影响因素进行分析,运用螺旋弹簧刚度理论建立了金属橡胶微元弹簧理论模型,并根据试验结果对其进行模型修正。通过理论模型与试验的比较,发现理论模型值与试验值较接近,可以较全面地反映金属橡胶静刚度特... 详细信息

对金属橡胶成形机理和静刚度特性影响因素进行分析,运用螺旋弹簧刚度理论建立了金属橡胶微元弹簧理论模型,并根据试验结果对其进行模型修正。通过理论模型与试验的比较,发现理论模型值与试验值较接近,可以较全面地反映金属橡胶静刚度特性,从而为金属橡胶减振器的设计和金属丝工艺参数的确定提供理论依据。

关键词：金属橡胶静刚度特性力学模型工艺参数

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古新世-始新世极热事件(PETM)浅海生态系统稳态转变:以塔里木盆地库孜贡苏剖面钙质超微浮游植物为例

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第四纪研究 2024年第5期44卷 1205-1214页

作者：梁瑞泽华春荣王亚苏苏虹姜仕军 Cui Ying 河海大学海洋学院江苏南京210098 阿荣旗第二中学内蒙古呼伦贝尔162750 暨南大学生命科学技术学院广东广州510632 Montclair State University USA Montclair NJ 07043

古新世-始新世极热事件(PETM)发生于56 Ma前,因其碳释放过程与当前人类CO_(2)持续排放驱动的全球变暖类似而备受世人关注。塔里木盆地保存完好、出露完整且连续的古近纪浅海地层为研究PETM期间东特提斯洋古环境变化提供了理想材料,但目... 详细信息

古新世-始新世极热事件(PETM)发生于56 Ma前,因其碳释放过程与当前人类CO_(2)持续排放驱动的全球变暖类似而备受世人关注。塔里木盆地保存完好、出露完整且连续的古近纪浅海地层为研究PETM期间东特提斯洋古环境变化提供了理想材料,但目前缺乏对PETM前后塔里木盆地浮游植物群落稳态转变的研究。本研究利用库孜贡苏剖面齐姆根组约48 m厚海相沉积物中保存的丰富钙质超微化石群落,研究PETM前后生态系统演变过程,揭示PETM事件前后发生了两次稳态转变。第一次稳态转变发生在沉积厚度约为19.61~24.56 m之间,与PETM事件开始时间恰好对应;第二次稳态转变发生在沉积厚度约为29.60~31.06 m之间,与PETM事件恢复期基本对应。PETM事件前Coccolithus pelagicus、Toweius pertusus和***等钙质超微化石占主导地位,当稳态开始发生改变时,***和***相对丰度开始下降,而“负偏属种”Discoaster araneus和Discoaster acutus开始出现。P和Zn/Al等营养指标升高,表明东特提斯洋地区在PETM期间初级生产力增加,高生产力指示种Neochiastozygus junctus在PETM期间显著增加也印证了这个观点。北大西洋中部滨海平原沉积记录表明,其生态系统在PETM时期同样经历了两次稳态变化,与库孜贡苏剖面两次转变时间基本对应,表明由PETM事件导致的浅海生态系统稳态转变可能是全球而非区域性变化。

关键词： PETM 钙质超微化石稳态转变塔里木盆地东特提斯洋

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伊朗南部Lurestan-Khuzestan地区中新统沉积物源特征

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沉积学报 2024年第5期42卷 1653-1669页

作者：孙高远崔希超陈嘉诺蒋璟鑫胡修棉王亚苏河海大学海洋学院南京210024 南京大学内生金属矿床成矿机制研究国家重点实验室地球科学与工程学院南京210023

【目的】阿拉伯和欧亚大陆碰撞导致了扎格罗斯造山带和前陆盆地的形成。扎格罗斯前陆盆地的持续充填致使海水最终从这一地区退出,实现了由海到陆的转变过程,从而为探讨新特提斯洋的消亡提供约束。【方法】对伊朗扎格罗斯Lurestan地区和K... 详细信息

【目的】阿拉伯和欧亚大陆碰撞导致了扎格罗斯造山带和前陆盆地的形成。扎格罗斯前陆盆地的持续充填致使海水最终从这一地区退出,实现了由海到陆的转变过程,从而为探讨新特提斯洋的消亡提供约束。【方法】对伊朗扎格罗斯Lurestan地区和Khuzestan地区的中新统Agha Jari组进行了系统的地层学、沉积学、砂岩岩石学和碎屑锆石U-Pb年代学研究,以揭示碎屑物质充填和海退过程。【结果】Lurestan地区Agha Jari组由中到厚层砂—泥岩互层组成,沉积环境分析其形成于河流环境。碎屑组分显示大量变质岩岩屑,结合170 Ma锆石年龄峰,指示盆地北侧Sanandaj-Sirjan岩浆变质带为其可能物源;Khuzestan地区Agha Jari组主要为底部钙质砂岩,向上逐渐变为厚层砂岩、泥岩组合,沉积于三角洲环境。砂岩碎屑组分以沉积岩屑为主,中生代锆石年龄与扎格罗斯褶皱冲断带一致,表明碎屑物源主要为再旋回的扎格罗斯褶皱冲断带中的沉积岩。基于下伏Gachsaran-Mishan组浅海蒸发岩和碳酸盐岩沉积,Agha Jari组记录了扎格罗斯前陆盆地由海向陆的转变过程。生物地层学资料约束残留海消亡的时间为不早于中新世早期,并且存在从西北向东南海退的趋势。【结论】阿拉伯—欧亚大陆初始碰撞作用导致扎格罗斯山脉隆起,随着持续隆升的扎格罗斯山脉向前陆盆地提供碎屑物质是导致扎格罗斯残留海关闭的直接原因,并且扎格罗斯残留海从西北向东南退出的古地理格局至少在中新世已经形成。

关键词：新特提斯洋扎格罗斯 Agha Jari组沉积环境海退

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手扶拖拉机、拖车机组行驶振动分析与行驶平顺性的初步评价

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农业机械学报 1983年第3期19卷 21-33页

作者：范永法吴起亚苏清祖王锦雯江苏工学院

本文用模态综合法建立了手扶拖拉机和拖车机组的四自由度数学模型,在此模型基础上导出了机组的加速度响应谱矩阵、及其与地面不平度谱之间的关系式。对机组在几种不同类型路面上的行驶振动作了测量,记录在磁带上的信号用JEF-16AN实时... 详细信息

本文用模态综合法建立了手扶拖拉机和拖车机组的四自由度数学模型,在此模型基础上导出了机组的加速度响应谱矩阵、及其与地面不平度谱之间的关系式。对机组在几种不同类型路面上的行驶振动作了测量,记录在磁带上的信号用JEF-16AN实时信号分析系统进行数据处理,进而对机组的平顺性按国际标准ISO2631和ISO/DIS5439作出了评价。

关键词：手扶拖拉机初步评价田园式拖拉机拖车挂车行驶平顺性乘坐舒适性振动分析

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