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《中国海洋大学学报(自然科学版)》2017,(7)
本研究针对渤海富营养化状态现场快速监测评估技术的需要,基于溶解氧(DO)、浊度(Tur)和叶绿素a(Chl a)这3个可现场实时监测的参数,以TRIX方法作为参照,将海水富营养化状态分为低风险和高风险两个水平,利用支持向量机建立了渤海富营养化状态快速评价技术,对训练集和测试集样品的富营养化状态分类准确率分别为100.0%和89.3%,交叉验证准确率为82.5%。所建立的渤海富营养化快速评价技术能够实现渤海富营养化状态的快速实时测评,可为渤海海洋环境监测提供技术支持。 相似文献
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日本福岛核电站爆炸引起的海洋放射性污染事故后果严重,沿海核电安全和海洋放射性环境的长期监测、污染预警和事故应急受到关注。文中研制了一套海洋核辐射现场监测装置,利用标准放射源~(241)Am,~(133)Ba,~(60)Co,~(137)Cs,~(152)Eu进行了能量刻度与分辨率刻度实验,并利用MATLAB进行了曲线拟合,得到的能量刻度曲线线性较好,~(137)Cs在661.6 keV的能量分辨率为6.8%。同时,该装置在青岛8号码头利用趸船吊挂方式进行了海水水下测试,测得海水中~(40)K的活度为12.42 Bq/L,与实验室检测结果的符合性较好。 相似文献
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海洋环境调查和监测的数据处理已与计算机技术结合在一起,但所采用的设备都是陆上标准的办公设备和个人电脑等,不适应海洋现场恶劣的使用环境,同时又缺乏现场数据采集部分,而这一部分对实时监测十分重要,以至海洋执法监察和海洋环境调查、监测及现场采样等许多工作都不能在现场进行数据分析处理, 相似文献
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《海洋地质与第四纪地质》2010,(6)
<正>日本南海海槽地震带实验(NanTroSEIZE)是一个并列和复合勘探项目,通过沿俯冲逆掩带的直接取样、现场测量、与实验室相连接的长期监测以及数字模拟,调查和研究断层力学和地震成因。南海海槽地震 相似文献
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在渤海冰区油气开发中,海冰给平台结构、油气运输和施工作业带来很大影响。油气作业区海冰参数精确、连续、实时的现场监测对分析油气开发的可靠性、检验海冰数值模式、校正海冰卫星遥感数据具有重要意义。针对渤海油气作业区的海冰运动和分布特性,通过数字图像技术对海冰的厚度、运动速度和密集度三个参数的提取进行了算法开发和软件研制。在2009-2010年采用该海冰数字图像监测软件对渤海辽东湾JZ20-2油气作业区的海冰参数进行了全冰期的连续监测,获得了翔实可靠的海冰厚度、密集度和冰速等海冰监测资料。现场监测应用表明,该海冰数字图像监测软件具有操作性强、精确度高、可靠性好的优点。该监测技术进一步完善后可广泛应用于渤海油气作业区的海冰现场监测,成为海冰业务化现场监测的重要组成部分。 相似文献
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海水化学需氧量(COD)是海水中有机污染物的综合指标,是海洋环境监测最重要的项目之一,目前我国海洋环境污染日趋严重,现有的COD测量方法远远不能满足形势的需要,研制开发现场、快速、自动、连续运行的“COD测量仪”势在必行,也是海水COD分析技术发展方向和发展趋势。在国家863计划的支持下,我们研制成功了可用于现场的“臭氧法海水化学需氧量测量仪”。文中介绍了臭氧法海水化学需氧量测量仪的原理、实验室现场试验结果和海试现场情况。大量实验数据表明,该测量仪具有测量快速、结果准确、长时间不需维护等特点。 相似文献
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考虑赤潮预警的业务需求,基于GIS平台、C/S(Client/Server)架构和2D web GIS服务平台,研发了赤潮预警系统,该系统由赤潮监测数据库、赤潮藻种库、赤潮预警模型、赤潮动态、赤潮历史资料和系统管理六大模块组成。可实现生态浮标监测、常规现场监测、应急监测、卫星遥感监测数据的实时采集入库、查询、显示、分析;能够开展基于天气模型的赤潮预警,赤潮漂移轨迹预报,对赤潮周边海水养殖、海水浴场休闲旅游进行示警。该系统为业务人员快速制作、发布赤潮预警,赤潮防灾减灾辅助决策支持等方面提供了支撑平台。 相似文献
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Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
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海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。 相似文献
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Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
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The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
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Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans 总被引:1,自引:0,他引:1
A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria ( 〉 99% ), but also between polar marine bacteria and bacteria from other aquatic environments ( ≥ 98.8% ), including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level. 相似文献
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The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献