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1.
海洋光学浮标   总被引:1,自引:0,他引:1  
海洋光学浮标(MarineOpticalBuoy-MOBY)1前言1994年2月21日在夏威夷Lanal海岸以外投放了海洋光学浮标(MOBY)。该浮标是在NOAA(美国国家海洋和大气管理局)、NASA(美国国家航空与航天局)的联合赞助下,由MODIS...  相似文献   

2.
于1997年10月-1998年1月,从胶州湾贝类养殖场购买栉孔扇贝,分别采用邻苯三酚自氧化法和过氧化氢法测定了其血细胞和血清中的超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活力,并对SOD类型的鉴别区分、SOD和CAT的热稳定性以及温度对SOD和CAT活力的影响进行研究。结果表明,血细胞中SOD和 CAT活力分别为312.7U和 124.4U,血清中SOD和CAT活力分别为102.3U和73.8U;冻存10d后,血清中SOD的活力丧失24.6%,而CAT的活力丧失40.8%;血细胞中CuZn-SOD和Mn-SOD的活力分别为193.4U和82.3U,血清中仅存在CuZn-SOD活性;血清中SOD的热稳定性很高,在80℃下保温30min后,酶活力仍很高,而CAT的热稳定性较低;血清中的SOD和CAT的最适温度分别为50℃和45℃。  相似文献   

3.
EDITORIALCOMMITTEE¥//AdvisersChen ̄n(ChenK ̄chenreM¥)TaDShipon(N#g)fbiAnbons(t¥#)wang ̄o(wangTe-ciaE¥B)LinBidden(LinPing-nam#*W)...  相似文献   

4.
实验研究海水中天然溶解有机物(DOM)在δ-MnO2、粘土和二氧化硅上的吸附,海水中溶解有机碳(DOC)在δ-MnO2、高岭石、伊利石和二氧化硅上的吸附率随pH的增加而减小。结果表明,在天然海水pH8.1条件下,海水中天然溶解有机物在这4种固体粒子上的吸附率大小为:δ-MnO2(32%)>伊利石(14%)>高岭石(4%)≈二氧化硅(3%)。根据统计热力学方法得到的公式能够很好地拟合海水中DOM在固体颗粒物上的吸附。  相似文献   

5.
无裂栉江珧种内同工酶表型差异的比较研究   总被引:9,自引:0,他引:9  
采用垂直板聚丙烯酰安梯度凝胶电泳对4种不同类型无裂栉江珧Atrina pectinata的肾脏、后闭壳肌和鳃组织进行了酯酶(EST)、过氧化物歧化酶(SOD)、乳酸脱氢酶(LDH)、苹果酸酶(ME)5中同工酶的比较研究。结果表明这4种类型的酶谱表达有差异,特别是肾组织的EST,后闭壳肌的EST、SOD和鳃组织的SOD、MDH的酶谱表型差异明显,其特征谱带可作为区别无裂栉江珧种内差异的一种分子标记。  相似文献   

6.
螺旋藻多糖对CD3AK细胞增殖能力的影响   总被引:7,自引:0,他引:7  
研究了螺旋藻多糖(PS)对CD3McAb激活的杀伤细胞(CD3McAb Activated Killer Cells,CD3AK Cells)增殖能力的影响。结果表明,当PS浓度为2.5μg·ml^-1培养体系条件下,对CD3AK细胞具有明显的刺激细胞增殖作用(P〈0.02);对培养长达23d的CD3AK细胞杀伤肿瘤细胞(K562细胞)的活性仍维持在较高的水平(46.5% ̄50%)。提示PS对辐射  相似文献   

7.
缺少密度或孔隙度测定数据的块体堆积速率的计算T.J.S.Sykes等块体堆积速率(MAR)计算已被应用于深海钻探计划(DSDP)和大洋钻探计划(ODP)岩心,以研究大洋盆地的沉积物演化,或把MAR数据分离成岩石学成分以决定方解石补偿深度(CCD)的历...  相似文献   

8.
关于《微体古生物在珠江口盆地新生代晚期层序地层学研究中的应用》一文的质疑SOMEQUESTIONSABOUTTHEARTICLETITLEDAPPLICATIONOFMICROPALEONTOLOGYTOTHESEQUENCESTRATIGRAPHI...  相似文献   

9.
答“关于《微体古生物在珠江口盆地新生代晚期层序地层学研究中的应用》一文的质疑”THEANSWERTOSOMEQUESTIONSABOUTTHEARTICLETITLEDAPPLI-CATIONOFMICROPALEONTOLOGYTOTHESEQUE...  相似文献   

10.
1ODP的发展历史ODP是原深海钻探计划(DSDP)的接续项目。GlomarChallenger号钻探船1983年退役之后,海洋科学家们为了能够在更深的海域作业并获取更深的样品,所以于1985年1月进行了首次试验性作业(Rabi-nowitz等,1985)后,在世界范围内具有重要地质意义的海区每两个月进行一个航次的海洋钻探。2ODP的组织系统总部设在美国德克萨斯州农工大学(TexasA&M)的ODP是一个国际联合科学研究组织,称为:深地层采样联合海洋研究机构,简称:JOIDES(JointOce…  相似文献   

11.
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   

12.
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   

13.
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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16.
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   

17.
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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19.
《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   

20.
Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges.  相似文献   

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