检索结果-南通市图书馆

The sound velocity and bulk properties of sediments in the Bohai Sea and the Yellow Sea of China

Acta Oceanologica Sinica 2016年第7期35卷 76-86页

作者： ZHENG Jiewen LIU Baohua KAN guangming LI Guanbao PEI Yanliang LIU Xiaolei key laboratory of marine Sedimentology and environmental Geology of State Oceanic Administration State Oceanic Administration Qingdao 266061 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Qingdao National laboratory for marine Science and Technology Qingdao 266237 China National Deep Sea Center State Oceanic Administration Qingdao 266237 China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of China Qingdao 266100 China

In order to investigate the correlation between a sound velocity and sediment bulk properties and explore the influence of frequency dependence of the sound velocity on the prediction of the sediment properties by the sound velocity, a compressional wave velocity is measured at frequencies of 25-250 kHz on marine sediment samples collected from the Bohai Sea and the Yellow Sea in laboratory, together with the geotechnical parameters of sediments. The results indicate that the sound velocity ranges from 1.232 to 1.721 km/s for the collected sediment samples with a significant dispersion within the series measuring frequency. Poorly sorted sediments are highly dispersive nearly with a positive linear relationship. The porosity shows a better negative logarithmic correlation with the sound velocity compared with other geotechnical parameters. Generally, the sound velocity increases with the increasing of the average particle size, sand content, wet and dry bulk densities, and decreasing of the clay content, and water content. An important point should be demonstrated that the higher correlation can be obtained when the measuring frequency is low within the frequency ranges from 25 to 250 kHz since the inhomogeneity of sediment properties has a more remarkably influence on the laboratory sound velocity measurement at the high frequency.

关键词： sound velocity particle composition physical properties frequency dispersion empirical equation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Long-term trend analysis of wave characteristics in the Bohai Sea based on interpolated ERA5 wave reanalysis from 1950 to 2020

引用

Acta Oceanologica Sinica 2022年第7期41卷 97-112页

作者： Jichao Wang Peidong Sun Zhihong Liao Fan Bi Guiyan Liu College of Science China University of PetroleumQingdao266580China National Meteorological Information Center Beijing100081China North China Sea marine Forecasting Center of State Oceanic Administration Qingdao266061China shandong provincial key laboratory of marine Ecological environment and Disaster Prevention and Mitigation Qingdao266061China

Reasonably understanding of the long-term wave characteristics is very crucial for the ocean engineering.A feedforward neural network is operated for interpolating ERA5 wave reanalysis in this study,which embodies a detailed record from 1950 onwards.The spatiotemporal variability of wave parameters in the Bohai Sea,especially the significant wave height(SWH),is presented in terms of combined wave,wind wave and swell by employing the 71 years(1950–2020)of interpolated ERA5 reanalysis.Annual mean SWH decreases at−0.12 cm/a estimated by Theil-Sen estimator and 95th percentile SWH reflecting serve sea states decreases at−0.20 cm/a.Inter-seasonal analysis shows SWH of wind wave has steeper decreasing trend with higher slopes than that of swell,especially in summer and winter,showing the major decrease may attribute to the weakening of monsoon.The inner Bohai Sea reveals a general decreasing trend while the intersection connecting with the Yellow Sea has the lower significance derived by Mann-Kendall test.Meanwhile,95th percentile SWH decreases at a higher rate while with a lower significance in comparison with the mean state.The frequencies of mean wave directions in sub-sector are statistically calculated to find the seasonal prevailing directions.Generally,the dominant directions in summer and winter are south and north.A similar variation concerning to SWH,the trend of the mean wave period is provided,which also shows a decrease for decades.

关键词： wave characteristic wind wave swell long-term trend Bohai Sea

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A positive trend in the stability of global offshore wind energy

引用

Acta Oceanologica Sinica 2024年第1期43卷 123-134页

作者： Chongwei Zheng Dalian Naval Academy Dalian 116018China marine Resources and environment Research Group on the Maritime Silk Road Dalian 116018China shandong provincial key laboratory of Ocean engineering Ocean University of ChinaQingdao 266100China

The recognition on the trend of wind energy stability is still extremely rare,although it is closely related to acquisition efficiency,grid connection,equipment lifetime,and costs of wind energy utilization.Using the 40-year(1979–2018)ERA-Interim data from the European Center for Medium-Range Weather Forecasts,this study presented the spatial-temporal distribution and climatic trend of the stability of global offshore wind energy as well as the abrupt phenomenon of wind energy stability in key regions over the past 40 years with the climatic analysis method and Mann-Kendall(M-K)test.The results show the following 5 points.(1)According to the coefficient of variation(C_(v))of the wind power density,there are six permanent stable zones of global offshore wind energy:the southeast and northeast trade wind zones in the Indian,Pacific and Atlantic oceans,the Southern Hemisphere westerly,and a semi-permanent stable zone(North Indian Ocean).(2)There are six lowvalue zones for both seasonal variability index(S_(v))and monthly variability index(M_(v))globally,with a similar spatial distribution as that of the six permanent stable zones.M_(v) and S_(v) in the Arabian Sea are the highest in the world.(3)After C_(v),M_(v) and S_(v) are comprehensively considered,the six permanent stable zones have an obvious advantage in the stability of wind energy over other sea areas,with C_(v) below 0.8,M_(v) within 1.0,and S_(v) within 0.7 all the year round.(4)The global stability of offshore wind energy shows a positive climatic trend for the past four decades.C_(v),M_(v) and S_(v) have not changed significantly or decreased in most of the global ocean during 1979 to2018.That is,wind energy is flat or more stable,while the monthly and seasonal variabilities tend to shrink/smooth,which is beneficial for wind energy utilization.(5)C_(v) in the low-latitude Pacific and M_(v) and S_(v) in both the North Indian Ocean and the low-latitude Pacific have an obvious abrupt phenomenon at the end of the20th century.

关键词： global oceans wind energy stability spatial-temporal distribution climatic trend

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Mantle sources of Cenozoic volcanoes around the South China Sea revealed by geochemical and isotopic data using the principal component analysis

引用

Journal of Oceanology and Limnology 2023年第2期41卷 562-574页

作者： Shuangshuang CHEN Zewei WANG Rui GAO Yongzhang ZHOU School of Earth Sciences and engineering Sun Yat-sen UniversityGuangzhou 510275China Southern marine Science and engineering Guangdong laboratory(Zhuhai) Zhuhai 519080China Guangdong provincial key Lab of geological Processes and Mineral Resources Guangzhou 510275China State key laboratory of marine environmental Science Xiamen UniversityXiamen 361102China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China State key laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Principal component analysis(PCA)was employed to determine the implications of geochemical and isotopic data from Cenozoic volcanic activities in the Southeast Asian region,including China(South China Sea(SCS),Hainan Island,Fujian-Zhejiang coast,Taiwan Island),and parts of Vietnam and Thailand.We analyzed 15 trace element indicators and 5 isotopic indicators for 623 volcanic rock samples collected from the study region.Two principal components(PCs)were extracted by PCA based on the trace elements and Sr-Nd-Pb isotopic ratios,which probably indicate an enriched oceanic island basalt-type mantle plume and a depleted mid-ocean ridge basalt-type spreading ridge.The results show that the influence of the Hainan mantle plume on younger volcanic activities(13 Ma)at the same location in the Southeast Asian region.PCA was employed to verify the mantle-plume-ridge interaction model of volcanic activities beneath the expansion center of SCS and refute the hypothesis that the tension of SCS is triggered by the Hainan plume.This study reveals the efficiency and applicability of PCA in discussing mantle sources of volcanic activities;thus,PCA is a suitable research method for analyzing geochemical data.

关键词： volcanic rocks geochemical indicators mantle source principal component analysis South China Sea

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The controlling factors of high suspended sediment concentration in the intertidal flat off the Huanghe River Estuary

引用

Acta Oceanologica Sinica 2020年第10期39卷 96-106页

作者： Bowen Li Yonggang Jia J.Paul Liu Jianfeng Su Xiaolei Liu Mingzheng Wen Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China laboratory for marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Department of marine Earth and Atmospheric SciencesNorth Carolina State UniversityRaleighNC 27695USA State key laboratory of marine Geology Tongji UniversityShanghai 200092China Tianjin Center China Geological SurveyTianjin 300170China

The Huanghe River(Yellow River)is known by its high suspended sediment concentration(SSC)in its river mouth tidal flat.However,the factors controlling the high SSC over there are not well understood.Therefore,we conducted 7-d hydrodynamic observations(water depth,wave height,and current velocity)and SSC measurements on the tidal flat off the Huanghe River Mouth.The data shows that in most of time,under the calm sea condition,the SSC ranges 0.1–3.5 g/L,and sediment discharge from the river is the main source.However,when hydrodynamics are enhanced in a tidal cycle and large-scale erosion occurs on the seafloor,resuspended sediment becomes the main source,and the SSC in the water column reaches 17.3 g/L.We find the suspended sediment flux is mainly controlled by the tidal current and Stokes drift,while the wave-induced shear stress could also affect the variation of suspended sediment flux.During the observation period,when sea under calm-rippled conditions,the current-induced resuspended sediment concentration(RSC)was greater than the wave-induced RSC.In contrast,in smooth-wavelet sea conditions,the wave-induced RSC was greater than the current-induced RSC,for instance,a single wave event was found to cause 11.8 cm seabed erosion within 6 h.This study reveals different controlling factors for the high SSC near a river-influenced tidal flat,and helps us get a better understanding of a delta's depositional and erosional mechanisms.

关键词： Huanghe River(Yellow River) sediment re-suspension sediment transport wave current in-situ observation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Phylogeny of Saccharina and Laminaria(Laminariaceae, Laminariales, Phaeophyta) in sequence-tagged-site markers

引用

Chinese Journal of Oceanology and Limnology 2014年第1期32卷 22-33页

作者：曲洁琼张静王绪敏池姗刘翠刘涛 College of marine Life Sciences Ocean University of China shandong provincial key laboratory of Microbial engineering Shandong Polytechnic University Chinese Academy of Sciences key laboratory of Genome Sciences and Information Beijing Institute of Genomics Chinese Academy of Sciences

Laminaria and Saccharina have recently been recognized as two independent clades from the former genus Laminaria. Traditional morphological taxonomy is being challenged by molecular evidence from both nucleus and plastid. Intensive work is in great demand from the perspective of genome colinearity. In this study, 118 sequence-tagged site(STS) markers were screened for phylogenetic analyses, 29 based on genome sequences, while 89 were based on expressed sequence tag(EST) sequences. EST-based STS marker development(29.37%) had an effi ciency twice as high as genome-sequence-based development(9.48%) as a result of high conservation of gene transcripts among the relative species. S. ochotensis, S. religiosa, S. japonica, and L. hyperborea showed great homogeneity in all 118 STS markers. Our result supports the view that the diversifi cation between the genera Saccharina and Laminaria was a more recent event and that Saccharina and Laminaria shared high phylogenetic affi nity. However, when it came to the single nucleotide polymorphism(SNP) level among the 41 SNPs, L. hyperborea owned 29 unique SNPs against 12 within the left three Saccharina species and 12 of the 13 indels were supposedly unique for L. hyperborea, indicated by its high variability. Originating from homologous ancestors, species between the recently diverged genera Laminaria and Saccharina may have taken in enough mutations at the SNP level only, in spite of different evolutionary strategies for better adaptation to the environment. Our study lays a solid foundation from a new perspective, although more accurate phylogenetic analysis is still needed to clarify the evolutionary traces between the genera Saccharina and Laminaria.

关键词：系统发育分析表达序列标签基因组序列 STS标记海带单核苷酸多态性褐藻 SNPs

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Three-dimensional DEM investigation of the stress-dilatancy relation of grain-cementing type methane hydrate-bearing sediment

引用

Petroleum 2021年第4期7卷 477-484页

作者： An Zhang Mingjing Jiang Wenhao Du School of Civil engineering Suzhou University of Science and TechnologySuzhouJiangsu215009China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao266000China State key laboratory for Disaster Reduction in Civil engineering Tongji University Shanghai200092China Department of Geotechnical engineering College of Civil EngineeringTongji UniversityShanghai200092China Department of Civil engineering Tianjin UniversityTianjin300072China Tongji Architectural Design(Group)Co. Ltd.No.1230 Siping RoadShanghai200092China

In this study,the Discrete Element Method(DEM)was employed to investigate numerically the effects of hydrate cementation and intermediate principal stress on the stress-dilatancy relation of graincementing type methane hydrate-bearing sediment(MHBS)by conducting a series of conventional and true triaxial tests.A novel 3D thermo-hydro-mechanical-chemical(THMC)contact model for MHBS was employed.The numerical results show that with increasing hydrate saturation and back pressure,or decreasing confining pressure,temperature and salinity,the stress-dilation relation of grain-cementing type MHBS evolves from dilation-dominant to bond-dominant.For the clean sand samples,the relationship between the normalized stress ratio h/Mcr and the dilatancy rate d is close under different intermediate principal stress coefficients.However,for the MHBS samples,this relationship is still affected by the intermediate principal stress coefficient b,due to the effect of hydrate cementation.

关键词： Stress-dilatancy Cementation Methane hydrate bearing sediment Discrete element method Intermediate principal stress

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Spatiotemporal distribution of fish eggs and larvae in the Huanghe(Yellow) River estuary, China in 2005–2016

引用

Journal of Oceanology and Limnology 2019年第5期37卷 1625-1637页

作者： SONG Yingfei ZHANG Longjun LUO Xianxiang key laboratory of marine environment and Ecology Ministry of Education College of Environmental Science and EngineeringOcean University of China

Decreasing fish resources in estuaries is a subject of anthropogenic activities. Studies of the spatiotemporal distribution of fish eggs and larvae can help identify the status and processes underlying recruitment in a fishery. As the fifth largest river estuary in the world, the Huanghe (Yellow) River estuary (HRE) is a typical estuary that has been seriously aff ected by human activities. Annual surveys on ichthyoplankton and environmental factors were conducted in the months of May of 2005 and 2009-2016 in the HRE to investigate the spatiotemporal distribution of fish eggs and larvae and the associated infl uencing factors. A total of 23 and 20 species of eggs and larvae, respectively, were collected. The dominant orders were Perciformes (51.2%) and Clupeiformes (25.6%). The average number of fish species eggs and larvae were 6.0 and 4.1 in average abundance of 0.91 and 0.13 ind./m^3 , respectively. The dominant species were mainly low-commercial-value small-sized fishes, such as Clupanodon punctatus , Harengula zunasi, and Acanthogobius, whereas certain traditional commercial fishes, such as Trichiurus lepturus , and Clupea pallasii, were not seen. Analysis of the fish egg and larval community revealed four temporal assemblages and two spatial assemblages. Salinity was the main factor on the spatial distribution of ichthyoplankton communities, the species number and Shannon-Weiner diversity index (H′) of the fish egg and larval community near the river mouth with lower salinity were signifi cantly lower than the community far away from the river mouth with higher salinity. In addition, increases of water temperature promoted the number and abundance of fish species eggs, and the areas of abundant prey tended to have a more diversified and abundant of ichthyoplankton species. In overall, overfishing, dam construction, and other human activities were the main drivers that led to the substantial decline in fishery resources in the HRE.

关键词： Huanghe ( Yellow) River estuary fish egg and larva environmental factors fishery resources human activity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Characterization of calcium deposition induced by Synechocystis sp. PCC6803 in BG11 culture medium

引用

Chinese Journal of Oceanology and Limnology 2014年第3期32卷 503-510页

作者：闫华晓韩作振赵辉周仕学迟乃杰韩梅寇小燕张艳徐琳琳田晨晨秦松 College of Chemical and environmental engineering Shandong University of Science and Technology shandong provincial key laboratory of Depositional Mineralization and Sedimentary Minerals College of Geological Science and EngineeringShandong University of Science and Technology State key laboratory of Mining Disaster Prevention and Control Shandong University of Science & Technology Yantai Institute of Coastal Zone Research Chinese Academy of Sciences

Calcium carbonate(CaCO 3) crystals in their preferred orientation were obtained in BG11 culture media inoculated with Synechocystis sp. PCC6803(inoculated BG11). In this study, the features of calcium carbonate deposition were investigated. Inoculated BG11 in different calcium ion concentrations was used for the experimental group, while the BG11 culture medium was used for the control group. The surface morphologies of the calcium carbonate deposits in the experimental and control groups were determined by scanning and transmission electron microscopy. The deposits were analyzed by electronic probe micro-analysis, Fourier transform infrared spectrum, X-ray diffraction, thermal gravimetric analysis and differential scanning calorimetry. The results show that the surfaces of the crystals in the experimental group were hexahedral in a scaly pattern. The particle sizes were micrometer-sized and larger than those in the control group. The deposits of the control group contained calcium(Ca), carbon(C), oxygen(O), phosphorus(P), iron(Fe), copper(Cu), zinc(Zn), and other elements. The deposits in the experimental group contained Ca, C, and O only. The deposits of both groups contained calcite. The thermal decomposition temperature of the deposits in the control group was lower than those in the experimental group. It showed that the CaCO 3 deposits of the experimental group had higher thermal stability than those of the control group. This may be due to the secondary metabolites produced by the algae cells, which affect the carbonate crystal structure and result in a close-packed structure. The algae cells that remained after thermal weight loss were heavier in higher calcium concentrations in BG11 culture media. There may be more calciumcontaining crystals inside and outside of these cells. These results shall be benefi cial for understanding the formation mechanism of carbonate minerals.

关键词：碳酸钙沉积培养基集胞藻傅里叶变换红外光谱透射电子显微镜差示扫描量热法晶体结构 CaCO3

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Using Natural Radionuclides to Trace Sources of Suspended Particles in the Lower Reaches of the Yellow River

引用

Journal of Ocean University of China 2024年第1期23卷 99-108页

作者： ZHANG Han BURNETT CWilliam ZHANG Xiaojie ZHAO Shibin YANG Disong NAN Haiming YU Zhigang XU Bochao Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China laboratory for marine Ecology and environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China College of Chemistry and Chemical engineering Ocean University of ChinaQingdao 266100China Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahasseeFL 32306USA North China Sea environmental Monitoring Center State Oceanic AdministrationKey Laboratory of Ecological Prewarning and Protection of Bohai SeaMNRQingdao 266033China shandong provincial key laboratory of marine Ecological environment and Disaster Prevention and Mitigation Qingdao 266033China

Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and desorption.We analyzed the activi-ties and distribution characteristics of multiple natural radionuclides(238U,226Ra,40K,228Ra,7Be and 210Pbex)on size-fractionated SPM at the Lijin Hydrographic Station(Huanghe or Yellow River)every month over a one-year period.Results showed that medium silt(16–32µm)was the main component.As expected,the activity of each radionuclide decreased with an increase of particle size.We examined the sources of SPM with different particle sizes using activity ratios of 226Ra/238U,228Ra/226Ra,40K/238U and 7Be/210Pbex,and concluded that SPM with different particle sizes originated from different sources.Our results indicate that fine SPM(32µm)was mainly derived from resuspension of riverbed sediment.During high runoff periods,the concentration of SPM increased significantly,and the pro-portion of fine particles originating upstream increased.Naturally occurring radioactive isotopes,especially on size-fractionated par-ticles,are therefore seen as useful tracers to understand the sources and behaviors of riverine particles transported from land to sea.

关键词： the Yellow River suspended particulate matter size-fractions radionuclides sediment sources water elutriator

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：