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Morphodynamic processes of the Elbe River estuary, germany： the Coriolis effect, tidal asymmetry and human dredging

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Frontiers of Earth Science 2014年第2期8卷 181-189页

作者： Maotian LI jianzhong ge Jens KAPPENBERG Dagmar MUCH Ohle NINO Zhongyuan CHEN State Key Laboratory of Estuarine and Coastal Research East China Normal University Shanghai 200062 China Institute for Coastal Research Helmholtz-Zentrum Geesthacht Max-Planck-StralSe 1 Geesthacht 21502 Germany Hamburg Port Authority Neuer Wandrahm 4 Hamburg 20457 Germany

The Digital Elevation Model （DEM） based on the historical sea-charts and on-site hydrological records were used to examine the morphological change of the Elbe River estuary. The results show that siltation predominated in the tidal flat in the northern estuary, with a net siltation rate of 1.8 cm· a^-1 during 1927-2006. In contrast, a continuous erosion prevailed in the main river channel, south of the estuary, with a net erosion rate of 2.5 cm· a^-1 in the same time. In addition, a seaward shift of the estuarine island has happened with the old island coalescing to the northern tidal flat and new one emerging through siltation process. The tidal asymmetry via ebbing flow （maximum at 140 cm· s^-1, and average at 76 cm· s^-1） prevailed in the tidal flat, meaning continuous aggradation northwestward, while flooding flow （maximum at 100 cm · s^-1, and average at 67 cm· s^-1） dominated in the main fiver channel with deepening thaweg at south, showing a landward sedimentation via the tidal pumping processes. This dextral extension of the estuarine morphology is due to the Coriolis force, leading to the inconsistent directions of in-out flows, which enables to facilitate the estuarine siltation. Human dredging prevailing in the estuary has dramatically altered the nature of the silted river channel to erosional since the last century net erosion rate of 3.2 cm· a^-1 This is characterized by a derived from the DEMs mapping, but only partially accounting for the dredging amount of 1994-2006, when the total dredging volume was 67 × 10^6m^3, equal to 5.9 cm·a^-1.

关键词： morphological evolution dextral forcing,DEMs the Elbe River estuary

台风“利奇马”对长江口水通量影响的数值模拟研究

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海洋预报 2024年第4期41卷 66-76页

作者：姚鼎李铖张凤林葛建忠张洪生郭文云上海海事大学海洋科学与工程学院上海201300 上海市海洋监测预报中心上海200062 华东师范大学河口海岸学国家重点实验室上海200062

在台风等极端天气影响下,河口水通量可能会在短时间内发生强烈变化。利用无结构有限体积海岸海洋模型FVCOM,研究了1909号台风“利奇马”对长江口水通量及分流比的影响。结果表明:台风“利奇马”可造成南槽持续30 h的净向陆水通量;受台... 详细信息

在台风等极端天气影响下,河口水通量可能会在短时间内发生强烈变化。利用无结构有限体积海岸海洋模型FVCOM,研究了1909号台风“利奇马”对长江口水通量及分流比的影响。结果表明:台风“利奇马”可造成南槽持续30 h的净向陆水通量;受台风影响,北支、北港、北槽和南槽4个入海口台风的入海净水通量都呈现相似的减小—增大—减小—恢复的变化规律,总净入海通量也呈现类似规律,且变化幅度可超过60%;台风总体上增大了北侧支汊的净分流比,减小了南侧支汊的净分流比。

关键词： FVCOM 台风影响水通量分流比长江口

Large-eddy simulation of the influence of a wavy lower boundary on the turbulence kinetic energy budget redistribution

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Journal of Oceanology and Limnology 2018年第4期36卷 1178-1188页

作者： LU Zongze FAN Wei LI Shuang ge jianzhong Ocean College Zhejiang UniversityZhoushan 316000China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China

Oceanic turbulence plays an important role in coastal flow. However, as the effect of an uneven lower boundary on the adjacent turbulence is still not well understood, we explore the mechanics of nearshore turbulence with a turbulence-resolving numerical model known as a large-eddy-simulation model for an idealized scenario in a coastal region for which the lower boundary is a solid sinusoidal wave. The numerical simulation demonstrates how the mechanical energy of the current is transferred into local turbulence mixing, and shows the changes in turbulent intensity over the continuous phase change of the lower topography. The strongest turbulent kinetic energy is concentrated above the trough of the wavy surface. The turbulence mixing is mainly generated by the shear forces; the magnitude of shear production has a local maximum over the crest of the seabed topography, and there is an asymmetry in the shear production between the leeward and windward slopes. The numerical results are consistent with results from laboratory experiments. Our analysis provides an important insight into the mechanism of turbulent kinetic energy production and development.

关键词： large-eddy simulation wavy lower boundary oceanic turbulence nearshore

A FVCOM-Based Unstructured Grid Wave, Current,Sediment Transport Model,*** Description and Validation

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Journal of Ocean University of China 2011年第1期10卷 1-8页

作者： WU Lunyu CHEN Changsheng GUO Peifang SHI Maochong QI Jianhua ge jianzhong Physical Oceanography Laboratoo Ocean University of China Qingdao 266100 P. R. China First Institute of Oceanography State Oceanic Administration Qingdao 266061 P. R. China School for Marine Science anti Technology University of Massachusetts-Dartmouth New Bedford Massachusetts USA State Key Laboratory of Estuarine and Coastal Research East China Normal University Shanghai 200062 P. R. China

An effort was made to couple FVCOM (a three-dimensional (3D),unstructured grid,Finite Volume Coastal Ocean Model) and FVCOM-SWAVE (an unstructured grid,finite-volume surface wave model) for the study of nearshore ocean processes such as tides,circulation,storm surge,waves,sediment transport,and morphological *** coupling between FVCOM and FVCOM-SWAVE was achieved through incorporating 3D radiation stress,wave-current-sediment-related bottom boundary layer,sea surface stress parameterizations,and morphology *** also includes a 3D sediment transport *** accurate fitting of irregular coastlines,the model provides a unique tool to study sediment dynamics in coastal ocean,estuaries,and wetlands where local geometries are characterized by inlets,islands,and intertidal marsh *** model was validated by two standard benchmark tests: 1) spectral waves approaching a mild sloping beach and 2) morphological changes of seabed in an idealized tidal *** Test 1,model results were compared with both analytical solutions and laboratory experiments.A further comparison was also made with the structured grid Regional Ocean Model System (ROMS),which provides an insight into the performance of the two models with the same open boundary forcing.

关键词： FVCOM coupling radiation stress wave-current-sediment-related bottom boundary layer morphology

Thorium anomaly on the lunar surface and its indicative meaning

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Acta geochimica 2024年第3期43卷 507-519页

作者： Jingyi Zhang jianzhong Liu Center for Lunar and Planetary Science Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The Moon has been divided into three terranes:Procellarum KREEP Terrane(PKT),Feldspathic Highland Terrane(FHT),and South Pole-Aitken Terrane(SPAT),using globally measured Th and *** lunar evolu-tion models have predicted that a lunar magma ocean will produce a residual layer enriched in incompatible elements such as K,REE,and P(i.e.,KREEP)in the late age of crys-tallization;and that the distribution of thorium can be used as a proxy for determining the global distribution of *** thorium distribution in these three terranes is *** highest concentration of thorium is in PKT,the medium concentration of thorium is in SPAT,and almost none in *** what is the specific distribution in each of the terrane and what enlightenment can it tell us?Here we present and describe the detailed thorium distribution in PKT,SPAT,and FHT and provide some information for the origin of asymmetries on the lunar surface.

关键词： Procellarum KREEP Terrane(PKT) Feldspathic Highland Terrane(FHT) South Pole-Aitken Terrane(SPAT) KREEP Thorium abundance

2-local unstable homotopy groups of indecomposable A3～2-complexes

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Science China Mathematics 2024年第3期67卷 607-626页

作者： Zhongjian Zhu jianzhong Pan College of Mathematics and Physics Wenzhou University Hua Loo-Keng Key Laboratory of Mathematics Institute of MathematicsAcademy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

In this paper,we calculate the 2-local unstable homotopy groups of indecomposable A3～*** main technique used is analysing the homotopy property of J（A,X）,defined by Gray（1973） for a CW-pair（X,A）,which is homoto... 详细信息

关键词： homotopy groups A 2 n -complexes fibration sequence relative James construction 55P15

Swimming velocity of spherical squirmers in a square tube at finite fluid inertia

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1481-1498页

作者： Tongxiao JIANG Deming NIE jianzhong LIN Institute of Fluid Mechanics China Jiliang UniversityHangzhou 310008China Key Laboratory of Impact and Safety Engineering(Ningbo University) Ministry of EducationNingbo 315211China Institute of Fluid Engineering Zhejiang UniversityHangzhou 310027China

The three-dimensional lattice Boltzmann method(LBM)is used to simulate the motion of a spherical squirmer in a square tube,and the steady motion velocity of a squirmer with different Reynolds numbers(Re,ranging from 0.1 to 2)and swimming types is investigated and analyzed to better understand the swimming characteristics of microorganisms in different ***,as the Reynolds number increases,the effect of the inertial forces becomes significant,disrupting the squirmer's ability to maintain its theoretical ***,as the Reynolds number increases,the structure of the flow field around the squirmer changes,affecting its velocity of ***,the swimming velocity of the squirmer exhibits a quadratic relationship with the type of swimming and the Reynolds ***,the narrow tube exerts a significant inhibitory effect on the squirmer *** addition,although chirality does not directly affect the swimming velocity of the squirmer,it can indirectly affect the velocity by changing its motion mode.

关键词： spherical squirmer swimming characteristics swimming velocity fow structure

Control of highly pathogenic avian influenza through vaccination

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Journal of Integrative Agriculture 2024年第5期23卷 1447-1453页

作者： Xianying Zeng jianzhong Shi Hualan Chen State Key Laboratory for Animal Disease Control and Prevention Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin150069China

The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian influenza virus in vaccinated birds would evolve more rapidly and pose a greater risk to *** this review,we summarize the successes in controlling highly pathogenic avian influenza in China and make suggestions regarding the requirements for vaccine selection and *** addition,we present evidence that vaccination of poultry not only eliminates human infection with avian influenza virus,but also significantly reduces and abolishes some harmful characteristics of avian influenza virus.

关键词： avian influenza control highly pathogenic vaccination

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离体拇外翻动物模型在骨科教学中的应用

中国继续医学教育 2024年第19期16卷 102-106页

作者：葛建忠许鹏张芝菱高靖宇吕晓东古锦瑞鲁永健陈涛涛阳泉市第一人民医院骨科山西阳泉045000

目的研究猪离体拇外翻动物模型在骨科教学中的应用效果。方法选取2021年3—9月在阳泉市第一人民医院住培的22名住培学员作为研究对象,根据随机数字表法将其分为将传统教学组及离体动物模型教学组,每组11名。所有住培学员均为第一次学习... 详细信息

目的研究猪离体拇外翻动物模型在骨科教学中的应用效果。方法选取2021年3—9月在阳泉市第一人民医院住培的22名住培学员作为研究对象,根据随机数字表法将其分为将传统教学组及离体动物模型教学组,每组11名。所有住培学员均为第一次学习外科学骨科部分课程,相同教师授课。传统教学组通过幻灯片或正常骨骼模型辅助教学,教学时长为2课时,每节课时50 min。离体动物模型教学组在传统教学的基础上,结合猪离体动物模型,通过授课教师对使用器械及离体动物模型的讲解,使住培学员对对拇外翻的骨骼结构、周围软组织建立初步认识,同时辅导住培学员在模型上进行手术操作,以加深对该疾病的理解,提高实践动手操作能力,教学时长为2课时,每节课时50 min。结课后统计考试成绩及教学满意度。结果传统教学组住培学员的住培学员成绩为(81.25±2.58)分,教学满意度评分为(42.65±3.15)分。离体动物模型教学组住培学员的住培学员成绩为(87.60±3.52)分,教学满意度评分为(47.25±2.21)分。离体动物模型教学组优于传统教学组,差异有统计学意义(P<0.05)。结论采用猪离体动物模型可以让住培学员更加直观地观察和理解拇外翻的解剖结构、手术原理,可以有效提高住培学员成绩,提升教学满意度,改善教学质量。

关键词：离体动物模型拇外翻骨科教学手术操作