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Magnetostratigraphy and paleoenvironmental record of late Cenozoic sediments in the Taiyuan Basin,North china

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Journal of Palaeogeography 2024年第4期13卷 971-992页

作者： Zhi-Qiang Feng Qian LI Wei han Kun-yuan Ma Yong-Jiang Liu Rong-Zhu Wei Yan-Wei Du Yong lei Guang-Hui Li College of Geoscience and Geomatics Engineering Taiyuan University of Technology Shanxi Institute of Geological Survey Frontiers Science Center for Deep ocean Multispheres and Earth System Key Lab of Submarine Geoscience and Prospecting TechniquesCollege of Manine GeosciencesOcean University of China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology College of Resources and environment Shanxi Agricultural University department of Information Engineering Shanxi University

The Taiyuan Basin is of importance for intraplate tectonic deformation in North china and contains Cenozoic strata with a maximum thickness of 3800 m.A～853.5-m-deep borehole (ZK01) with an overall core recovery rate of 85.09%was drilled at Yuci (37°35'37?N,112°39'47?E) in the central Taiyuan Basin,to obtain high-resolution records of paleomagnetism,paleoclimatic and paleoenvironmental conditions,and depositional environment of the *** obtained magnetic polarity sequence consists of 13 normal and 12 reverse zones,which correspond to C1n-C4An.2n of the geomagnetic polarity time *** data show that the evolution of ZK01 core covers the interval from 8.1 Ma to the present,and the bottoms of Pliocene,Quaternary,and Middle Pleistocene were identified in Taiyuan Basin,with a sedimentary accumulation rate ranging from 62.5 m/Ma to 175.9 m/*** data reveal that the source rocks in the study area underwent intense weathering and the sediments mainly formed in a semi-arid and oxygen-rich *** addition,paleoclimatic changes occurred at～7 Ma,3.8 Ma,and 1.7 Ma,which can be closely related to the tectonic uplift of the Loess Plateau and Tibetan Plateau,as well as the variations in the Asian monsoon and associated regional and global climatic change.

关键词： Taiyuan Basin Core sediment Magnetostratigraphy Climate change Paleoenvironment Quaternary

Virtual-Leader-follower Structure and Finite-time Controller based Cooperative Control of Multiple Autonomous Underwater Vehicles

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Virtual-Leader-follower Structure and Finite-time Controller...

Chattering-free Finite-time Tracking Control Algorithms with Variable Structure for Mobile Robots

第24届中国控制与决策会议

作者： ZHOU Zhong-Hai 1, 2, 3 yuan Jian 2, 3* ZhanG Wen-Xia 4 ZHAO Jin-Ping 1 (1. College of Physical and environmental oceanography, ocean university of china, qingdao, 2661002. Shandong Provincial Key Laboratory of ocean environment Monitoring Technology, qingdao, 2660013. Institute of oceanographic Instrumentation of Shandong Academy of Science, qingdao, 266001 4.Mechanical & Electrical Engineering department, Qindao College, qingdao Shandong, 266016)

The formation control for large-scale multiple autonomous underwater vehicles is investigated. A formation control scheme to combinate leader-follower with virtual structure is introduced;AUVs with underwater communication rage constraints are divided into some clusters according to their relative postions in space, and leaders in all clusters can track their desired trajectories based on virtual structure;followers within all clusters follow the corresponding leader as their desired tracking trajectory. We realize the larege-scale formation control with the proposed formation scheme and the finite-time controller proposed in our previous work. Numerical simulation results show the effectiveness of the control strategy.

关键词： Autonomous Underwater Vehicle Large-scale Formation Control Virtual-leader-follower Hierarchical Structure Feedback Linearization, Finite time

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Chattering-free Finite-time Tracking Control Algorithms with...

水动力条件差异导致潮坪分形特征变化实例研究

第24届中国控制与决策会议

The trajectory-tracking problem for mobile robot is considered. A compound finite-time tracking control linearization algorithm base on feedback linearization and variable structure is proposed, and the reaching-control law is used to drive the steering angle trajectory with large inertial error exponentially toward the given switching surface neighborhood. When the steering angle trajectory is inside the neighborhood, the chattering-free control law based on continuous state-feedback drives the trajectory to the switching surface precisely while converting the original nonlinear system into a reduced system;state-feedback control law for the reduced system is then designed to stabilize the position error in finite time. Numerical simulations show the desired trajectory is attained fully in finite-time without chattering.

关键词： Mobile robot trajectory tracking finite time variable structure chattering-free

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海洋学报 2003年第3期25卷 59-67页

作者：贾永刚付元宾许国辉单红仙曹雪晴中国海洋大学环境建设系山东青岛266003

研究区位于1964～1976年黄河由刁口流路入海时形成的三角洲潮坪。为进行石油开采在潮坪上构筑的交通设施对波浪形成了良好的屏障,水动力条件具有显著差异的屏障两侧潮坪是研究潮坪特征对水动力条件响应的天然实验场所。在屏障两侧各选... 详细信息

研究区位于1964～1976年黄河由刁口流路入海时形成的三角洲潮坪。为进行石油开采在潮坪上构筑的交通设施对波浪形成了良好的屏障,水动力条件具有显著差异的屏障两侧潮坪是研究潮坪特征对水动力条件响应的天然实验场所。在屏障两侧各选择一典型区,实测地貌形态,取样品进行粒度成分分析,根据实测资料分析确定潮坪分形特征。发现水动力环境的强弱决定着潮坪的形貌、沉积物粒度分维值的变化规律。水动力环境强的一侧潮坪滩面分维值高,且随着初始计算网格宽度增大迅速降维;表层沉积物粒度分维值小,且离散性大。相反,在另一侧潮坪滩面分维值低,且随着初始计算网格宽度增大分维值无显著变化;表层沉积物粒度分维值高,且具有较好的一致性。当初始计算网格宽度增大到某个值时,两侧潮坪形貌分维值渐趋一致。在屏障两侧各沿一条与屏障大角度相交的测线取样,并各选择一点采取不同深度的样品做分析计算,发现在水动力条件弱的一侧,样品的粒度分维值表现为远离屏障逐步降维、随深度增加分维值增大的规律;相反一侧粒度分维值变化的规律性很不明显。讨论了水动力环境对潮坪分形特征影响机理。

关键词：水动力环境潮坪分形粒度分维黄河口

Anti-oxidant and anti-inflammatory activities of ultrasonicassistant extracted polyphenol-rich compounds from Sargassum muticum

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Journal of oceanology and Limnology 2019年第3期37卷 836-847页

作者： YU yuan WANG Le FU Xiaoting WANG lei FU Xiaodan YANG Min han Zhenlian MOU Haijin JEON You-Jin College of Food Science and Engineering Ocean University of ChinaQingdao 266003China department of Marine Life Sciences Jeju National UniversityJeju 63243Republic of Korea

Polypehnol is an important,potentially bioactive component of Sargassum *** this study,ultrasonic assisted extraction of polyphenol-rich substances was performed using a 38%ethanol solution at a solid:liquid ratio of 1:30 at 68℃ for 32min,determined by single-factor and response surface methodology(RSM)*** content of polyphenol was 5.66mg/g in the crude *** extraction showed that the polyphenol mainly distributed in ethyl acetate(SKEE)and water phases(SKEW).The anti-oxidation test by electron spin resonance(ESR)spectrum showed that the SKEE had the strongest scavenging activity on DPPH(1,1-diphenyl-2-picrylhydrazyl)and alkyl *** was shown noncytotoxic but could inhibit the generation of cellular ROS,showing protective effects in H2O2 and AAPHinduced Vero cells and UV-B irradiated HaCaT *** also signifi cantly inhibited the release of NO of LPS-induced RAW 264.7 ***,the polyphenol-rich extracts in ethanol and ethyl acetate showed excellent anti-oxidant and anti-infl ammatory activities,which is beneficial to the development of high-value bio-substances.

关键词： Sargassum muticum polyphenol extraction ESR anti-oxidant anti-inflammatory

Bi_(2)O_(2)Se nanoplates for broadband photodetector and full-color imaging applications

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Nano Research 2023年第5期16卷 7638-7645页

作者： han Wang Songqing Zhang Xingxuan Wu Huijia Luo Junliang Liu Zesheng Mu Ruirui Liu Guang yuan Yujun Liang Jin Tan Yongling Ren Wen lei department of Electrical Electronic and Computer EngineeringThe University of Western AustraliaCrawley 6009Australia department of Electronic Engineering School of IOT engineeringJiangnan UniversityWuxi 214122China College of Information Science and Engineering Ocean University of ChinaQingdao 266100China Faculty of Materials Science and Chemistry China University of GeosciencesWuhan 430074China

Broadband light detection and sensing are widely applied in modern *** a promising candidate for next-generation two-dimensional(2D)optoelectronic material,bismuth oxyselenide(Bi_(2)O_(2)Se)nanoplates exhibit many prospects in the application of visible light detection due to their peculiar *** this work,we report the photodetection performance of single-crystal 2D Bi_(2)O_(2)Se nanoplates grown on SiO_(2)based on a ternary-alloy growth model by utilizing chemical vapor deposition(CVD).The Bi_(2)O_(2)Se nanoplates were found to have an even and uniform square shape with side lengths up to 15μm and an approximate thickness of 15 nm.A visible-light photodetector was fabricated based on a CVD-grown Bi_(2)O_(2)Se nanoplate,and characterized by a set of illumination experiments using a 400 nm laser at temperatures ranging from 77 to 370 *** device exhibited superior performance at the temperature of 77 K,with a responsivity of 523 A/W,a specific detectivity of 1.37×10^(11)Jones,a response time of 0.2175 ms,an external quantum efficiency of 162,119.44%,resulting in high-quality and fullcolor imaging in the visible *** results indicate that the single-crystalline Bi_(2)O_(2)Se nanoplates have excellent potential in broadband photodetection and non-cryogenic imaging.

关键词： two-dimensional(2D)nanomaterial Bi_(2)O_(2)Se nanoplates chemical vapor deposition broadband light detection full-color imaging

Climate change attribution of the 2021 Henan extreme precipitation: Impacts of convective organization

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Science china Earth Sciences 2022年第10期65卷 1837-1846页

作者： han QIN Wei yuan Jun WANG Yang CHEN Panxi DAI Adam HSOBEL Zhiyong MENG Ji NIE Laboratory for Climate and ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China Aviation Meteorological Center Civil Aviation Administration of ChinaBeijing 100621China Key Laboratory of Regional Climate-environment for Temperate East Asia(RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China department of Atmospheric Science School of Earth SciencesZhejiang UniversityHangzhou 310027China department of Applied Physics and Applied Mathematics and Lamont-Doherty Earth Observatory Columbia University

In this study, we investigate the climate attribution of the 21·7 Henan extreme precipitation event. A conditional storyline attribution method is used, based on simulations of the event with a small-domain high-resolution cloud-resolving model. Large-scale vertical motion is determined by an interactive representation of large-scale dynamics based on the quasigeostrophic omega equation, with dynamical forcing terms taken from observation-based reanalysis data. It is found that warming may lead to significant intensification of both regional-scale(10–14% K, depending on convective organization) and station-scale precipitation extremes(7–9% K^(-1)). By comparing clustered convection organized by a localized surface temperature anomaly and squall-line convection organized by vertical wind shear, we further explored how convective organization may modify precipitation extremes and their responses to warming. It is found that shear convective organization is much more sensitive to large-scale dynamic forcing and results in much higher precipitation extremes at both regional and station scales than unorganized convection is. The clustered convection increases station-scale precipitation only slightly during heavy precipitation events. For regional-scale extreme precipitation sensitivity, shear-organized convection has a larger sensitivity by 2–3% Kthan that of unorganized convection, over a wide temperature range, due to its stronger diabatic heating feedback. For the station-scale extreme precipitation sensitivity, no systemic dependence on convective organization is found in our simulations.

关键词： Extreme precipitation Global warming Climate change attribution Convective organization Hourly precipitation

Neoproterozoic Diamictite of the Luoquan Formation from the North china Block and Their Implications

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Journal of Earth Science 2023年第4期34卷 1128-1139页

作者： Peishan Sui Weidong Sun Nan han lei Wang Shiwen Xie Zihang Huang Xiaohong Wang Hongmei Gong Jin Liu Jinyan Lin yuanyuan Xiao CAS Key Laboratory of Marine Geology and environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Center of Deep-Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China Changqing Oilfield Exploration and Development Research Institute Xi'an 710018China Yanchang Oilfield Exploration and Development Technology Research Center Xi'an 716001China Beijing SHRIMP Center Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Public Technology Service Center Institute of OceanologyChinese Academy of SciencesQingdao 266071China department of Geology Northwest UniversityXi'an 710069China

Glacial diamictite may provide important information on paleoenvironment and average composition of the upper continental crust(UCC).In this study,we report sedimentary facies,petrological and geochemical characteristics of Neoproterozoic diamictite from a profile of the Luoquan Formation on the southern margin of the North china Block(NCB).Upwards the sampling profile,lithostratigraphic strata vary from massive diamictite with poorly sorted carbonate gravels to laminated diamictite with small gravels of terrestrial detrital *** the profile,CaO-MgO-LOI-Sr values decrease with the increase of SiO_(2)-Al2O_(3)-K2O *** these petrological and geochemical variations indicate a change from lodgement till deposition in the proximal of ice sheet to ice-rafting deposition in glacial-marine environment with less dolomite to supply their *** with previous studies on diamictite from other outcrops on the NCB,the deposition of Luoquan diamictite reflects that the glaciation on the NCB vanished and the ice-rafting effect weakened with glacial transgression *** addition,significant co-variations of various elements with La and Al2O_(3)confirm the significant conservation of most analyzed elements during the sedimentary processes to produce diamictite.

关键词： diamictite North china Craton paleoenvironment the Luoquan Formation Neopro-terozoic sedimentation.

渤海湾北部滦河三角洲晚更新世以来沉积环境划分及碳埋藏速率的评价

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中国地质 2022年第5期49卷 1555-1570页

作者：陈皓何磊叶思源韩宗珠袁红明 Edward ALaws 中国海洋大学海洋地球科学学院山东青岛266003 中国地质调查局滨海湿地生物地质重点实验室青岛海洋地质研究所山东青岛266071 青岛海洋科学与技术国家实验室海洋地质过程与环境功能实验室山东青岛266061 路易斯安那州州立大学海岸与环境学院美国巴吞鲁日70803-4110

【研究目的】开展渤海湾北部滦河三角洲晚更新世以来不同沉积环境的划分,计算分析碳埋藏速率的大小和控制因素,进一步评价区域碳储能力。【研究方法】本文对BXZK03孔岩芯开展晚更新世以来的古沉积环境恢复,并取样分析了包括粒度、年代(A... 详细信息

【研究目的】开展渤海湾北部滦河三角洲晚更新世以来不同沉积环境的划分,计算分析碳埋藏速率的大小和控制因素,进一步评价区域碳储能力。【研究方法】本文对BXZK03孔岩芯开展晚更新世以来的古沉积环境恢复,并取样分析了包括粒度、年代(AMS14C和OSL)、含水量、有机碳、总碳和其他营养成分等在内的测试指标。【研究结果】该孔晚更新世以来地层自下而上划分为泛滥平原、海滩沙脊、浅海、障壁沙坝(三角洲前缘)和潟湖的沉积环境单元,各沉积单元平均有机碳埋藏速率大小依次为:障壁沙坝51.47 g/(m^(2)·a)>海滩沙脊32.59 g/(m^(2)·a)>浅海7.82 g/(m^(2)·a)>潟湖4.66 g/(m^(2)·a)。总碳、有机碳与各营养元素具有显著(P1)线性相关关系,方差分析显示沉积速率和碳浓度分别是滦河三角洲碳埋藏速率的主要控制因素。【结论】滦河三角洲沉积物中有机碳浓度相对较低,但是在全新世三角洲沉积速率较高,使得有机碳埋藏速率也相对较高,因此具有一定的碳储能力。

关键词：有机碳碳储能力埋藏速率沉积环境气候变化滦河三角洲海洋与环境地质调查工程渤海湾天津河北