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1.
用磁力浮沉子密度测量装置,在１５ ～２５ ℃之间的三个温度下测定了杭州湾３０ 个水样的密度。结果表明,测定值皆高于相应条件下国际标准海水状态方程的计算值,在海水盐度范围５．５６～２６ ．４ ,密度平均偏差值为２８ ．２ ～１２０ ．５ ×１０－ ３ｋｇ／ｍ３ 。测定密度和计算密度的偏差随盐度的降低而增大,与盐度的变化成直线相关;与（Ｃａ２ ＋ ）／Ｓ和比碱度之间皆呈指数曲线相关。杭州湾海水枯水期和丰水期水样的（Ｃａ２ ＋ ）／Ｃｌ 比平均值分别超出大洋水平均值２８ ．８％ 和２０ ．６％ ;杭州湾海水枯水期和丰水期的比碱度平均值分别超出大洋水平均值６０ ．３ ％ 和３０２ ％ ;（Ｍｇ２ ＋ ）／Ｃｌ 比、枯水期水样ＳＯ２ －４ ／Ｃｌ 比及Ｓｒ２ ＋ ／Ｃｌ 比与大洋水平均值相同或相近,丰水期水样ＳＯ２ －４ ／Ｃｌ 高出大洋水平均值７ ．１ ％ ;结合主要离子在湾内平面分布图,得出杭州湾海水高的Ｃａ２ ＋ ／Ｃｌ 比、比碱度和ＳＯ２ －４ ／Ｃｌ 比,除了受江水输入影响以外,主要还是受湾北岸工业区废水排放的影响。并首次给出了杭州湾海水的密度公式。 相似文献
2.
９９４年９月采集了珠江口表层海水水样,并对其溶解态的Ｋ＋、Ｎａ＋、Ｃａ２＋、Ｍｇ２＋、ＳＯ２－４、Ｃｌ等化学要素进行了测定。结果表明,珠江口调查海域表层水中溶解态的Ｋ＋、Ｎａ＋、Ｃａ２＋、Ｍｇ２＋、ＳＯ２－４主要受陆源淡水与外海水物理混合稀释的影响,与Ｃｌ具有良好的直线正相关;Ｃａ２＋／Ｃｌ、ＳＯ２－４／Ｃｌ明显高于大洋水相应比值,Ｎａ＋／Ｃｌ、Ｍｇ２＋／Ｃｌ略高,而Ｋ＋／Ｃｌ比大洋比值低;在与中国其它各主要河口表层水对应Ｃｌ比较中,珠江口的ＳＯ２－４／Ｃｌ较高,而Ｃａ２＋／Ｃｌ,Ｍｇ２＋／Ｃｌ比值居低;上述各主要常量离子和Ｃｌ的等值线均沿自北向南走向递增。 相似文献
3.
探讨Ｂａ２＋离子搀杂对（Ｃａ０．５Ｓｒ０．５）５（ＰＯ４）３Ｃｌ：Ｅｕ２＋和（Ｃａ０．４Ｓｒ０．６）５（ＰＯ４）３Ｃｌ：Ｅｕ２＋量子发光效率的影响。当用Ｂａ２＋离子代替Ｃａ２＋或Ｓｒ２＋离子进入晶体时，Ｅｕ２＋离子的发光特性发生改变：发射峰的峰值降低，热猝灭的温度升高。并采用位型坐标理论给予解释。根据晶体的结构特征，对占据两个不等当晶体学位置的Ｅｕ２＋离子发光中心之间的能量传递进行了探讨 相似文献
4.
长江三角洲地区晚第四纪古土壤地球化学特征 总被引：1，自引：0，他引：1
首次研究长江三角洲地区晚第四纪古土壤的地球化学特征。本区第一“暗绿色硬粘土层”的硅铝率在２．８０～３．３７之间,说明该层已经发生了较强的土壤化作用,可以确定为古土壤。古土壤层土体样品与胶体样品的化学全量分析结果之间有很大的差异,只能用胶体样品来研究古土壤特征。在古土壤中,ＳｉＯ２、Ａｌ２Ｏ３、ＭｇＯ、ＴｉＯ２、Ｋ２Ｏ相对积聚,而Ｆｅ２Ｏ３、ＣａＯ、ＭｎＯ、Ｎａ２Ｏ、Ｐ２Ｏ５相对淋溶。在剖面上,ＳｉＯ２／（ＭｇＯ＋ＣａＯ）的分子比值变化规律表明气候逐渐湿润 相似文献
5.
改性膨润土对赤潮落种及海水中DRP,COD的去除效应 总被引：3，自引：0，他引：3
实验室研究了不同条件制备的改性膨润土对赤潮生物及海水中ＤＲＰ,ＣＯＤ的去除效应,结果表明,改性膨润土有效Ａｌ为１．５％时去除效应最好,经Ｎａ２ＳＯ４,Ａｌ２（ＳＯ４）３改性的膨润土在ｐＨ＝５．５时去除效应最佳,改性膨润土的去除效率随Ａｌ／ＳＯ４比值增加而增加,改性膨润土添加絮凝剂醋甲壳质和Ｃａ（ＯＨ）２提高了去除功效。 相似文献
6.
将４种不同浓度的Ｃａ＾２＋溶液灌注罗非鱼嗅上皮,观测其对罗非鱼嗅电图（ｅｌｅｃｔｒｏｏｌｔａｃｔｏｇｒａｍ,简称ＥＯＧ）电位幅值的影响,结果表明：Ｃａ＾２＋对罗非鱼ＥＯＧ具双重效应,在一定浓度范围（１～４ｍｍｏｌ／ｄｍ＾３）内,随着Ｃａ＾２＋对ＥＯＧ的效应由抑制逐渐转向促进,表现为反应的增大与Ｃａ＾２＋浓度的提高呈正相关。但当Ｃａ＾２＋浓度进一步提高到８ｍｍｏｌ／ｄｍ＾３时,ＥＯＧ反映减小,呈现抑制效应,本文探讨了Ｃａ＾２＋影响ＥＯＧ的可能机制。 相似文献
7.
冲绳海槽晚更新世以来环境演变的矿物-地球化学记录 总被引：2，自引：0，他引：2
国家自然科学基金资助项目（Ｎｏ．４９６７６２９０,１９９７～１９９９）“冲绳海槽晚更新世以来环境演变的矿物 地球化学记录” ,根据表层和柱状样品的成因矿物学和地球化学研究 ,重建了冲绳海槽中部自晚更新世以来的环境演变历史。沉积物的ＴｉＯ２ （ＴＦｅ２Ｏ３ ＭｇＯ）,Ｋ２Ｏ／Ｎａ２Ｏ （ＴＦｅ２Ｏ３ （ＴＦｅ２Ｏ３ ＭｇＯ）,Ａｌ／（Ａｌ Ｍｎ Ｆｅ）,Ｌａ／Ｙｂ ＲＥＥ,ＬＲＥＥ／ＨＲＥＥ（平均８．６９） ,δＥｕ（平均０．６０）和轻稀土型配分类型特征判明为活动大陆边缘 大陆岛弧型沉积环境 ,沉积物具有典型… 相似文献
8.
台湾海峡西部海域水体中的二氧化碳体系 总被引：7，自引：0，他引：7
据１９８４年５月至１９８５年２月的调查资料，计算了该水体中二氧化碳体系各要素的统计值，着重研究了它们的季节变化及其与水文，化学和生物因子的关系。结果表明该水体中ＰＣＯ２，ＣＯ２（Ｔ），ＣＯ＾２＾－３，ＨＣＯ３，∑ＣＯ２，ＣＯ＾２＾－３／∑ＣＯ２，ＨＣＯ３／∑ＣＯ２，ＨＣＯ２，ＣＯ２（Ｔ），ＣＯ＾２＾－３，∑ＣＯ２／Ｃｌ，Ωｃ，Ωａ和Ｃ：Ｎ：Ｐ平均值依次分别为２５１ｄＰａ，８．４３μｍｏｌ／ｄｍ×３ 相似文献
9.
九龙江口生物可利用磷的行为与人海通量 总被引：1，自引：1，他引：0
于１９９５年３、５月在九江口进行两个航次的现场调查,研究不同形态磷的河口行为,并估算生物可利用磷的入海通量。结果表明,在Ｓ〈２０区域内,溶解活性磷（ＤＲＰ）的行为受控于“缓冲机制”,其含量在８－１０μｇ／ｄｍ＾３水平上下波动。颗粒磷中ＭｇＣｌ２可提取磷（ＭｇＣｌ２－Ｐ）含量随盐度增大而增大,并与叶绿素ａ以及悬浮物Ｆｅ、Ｍｎ、Ａｌ含量呈正相关关系。ＮａＯＨ／ＮａＣｌ可提取磷（ＮａＯＨ／ＮａＣｌ－Ｐ） 相似文献
10.
用磁力浮沉子密度测量装置,在１５ ～２５ ℃之间的三个温度下测定了珠江口２０ 个水样的密度。结果表明,测定值皆高于相应条件下国际标准海水状态方程的计算值,在海水盐度范围０．０８～３３ ．４４６ ,密度平均偏差范围为２ ．４ ～５４．０ ×１０ － ３ｋｇ／ｍ３ 。测定密度和计算密度的偏差随盐度的降低而增大,与盐度的变化成直线相关：与（Ｃａ２ ＋ ）／Ｓ、ＳＯ４２ － ／Ｓ比和比碱度之间皆呈指数曲线相关。珠江口水样（Ｃａ２ ＋ ）／Ｃ１ 、ＳＯ４２ － ／Ｃ１ 和比碱度平均值分别超出大洋水平均值１７ ．８ ％ 、８ ．２１ ％ 和１５２ ％ ,其余的Ｎａ ＋ ／Ｃ１、Ｋ＋ ／Ｃ１ 和Ｓｒ２ ＋ ／Ｃ１ 比值与大洋水无明显差别,基本类同。珠江口海水的高碱度、高（Ｃａ２ ＋ ）／Ｃ１ 和高ＳＯ４２ － ／Ｃ１ 是造成其海水密度正偏差的主要因素。经计算机拟合,首次导出了珠江口海水密度的状态方程,该方程计算值与实验值的平均标准偏差为±２．５×１０－ ３ｋｇ／ｍ３ 。 相似文献
11.
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
12.
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
13.
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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15.
《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
16.
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
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18.
Rahul Sharma 《Marine Georesources & Geotechnology》2000,18(3):237-250
Observations on seafloor features from subbottom profiling and seabed photography data show that the undisturbed and natural conditions before the benthic disturbance undergo a substantial change after operation of the disturber. The effects can be seen in the form of deep trenches and grooves, formed by the action of the sleds and the pumping of the sediment along its path, as well as sediment piles on either side of the track. Biological traces such as fecal coils, casts, tubes, burrows, and trails get obliterated in the areas of disturbance and resedimentation. The smooth, uniform nature of the seafloor observed in predisturbance phase shows microtopographic changes in and around the disturbed area as a result of sediment excavation and resettlement. Vertical mixing as well as lateral transport of sediment alter the geological, biological, physical, and chemical conditions on the seafloor, which need to be monitored over time to assess the process and the time taken for restoration of environmental conditions. 相似文献
19.
Vance P. Vicente 《Marine Ecology》1989,10(2):179-191
Abstract. Long-term changes in the distributional patterns of commercial sponges ( Spongia spp. and Hippospongia spp.) within the West Indian Region indicates that: 1) commercial sponges had a widespread distribution throughout the whole West Indian Region and were ubiquitous in very shallow water until about the first half of the present century; 2) they were fished commercially not only in the traditional northern Caribbean sites (Florida, Gulf of Mexico, Bahamas) but also in the Greater ( e. g. , Hispaniola, Jamaica) and Lesser Antilles; and 3) they became extinct throughout most of the Lesser Antilles ( e. g. , Puerto Rico, Vieques, St. Thomas) sometime during the first half of this century. Mortalities of spongiids within the Antilles were found to differ from other marine mortalities in that: 1) species disappeared from a large region; 2) species vanished from different habitats and depths; and 3) natural populations never recovered. Species richness patterns suggest that commercial sponge genera ( Spongia and Hippospongia ) evolved under slightly cooler elimatic conditions than those found at present, and that these extinctions occurred as a direct or indirect effect of positive thermal anomalies in sea surface and atmospheric temperatures between 1900–1950. The concept that species diversity is stable on a regional scale is questioned. 相似文献
20.
The behaviour of an axially pre-loaded cylindrical member of an offshore structure, hit by a supply ship, has been investigated. The effects of axial pre-loading on the dynamic properties of members, the extent of damage and propagation of dynamic instability in the tubular members have also been investigated. Numerical models have been validated using available experimental data from the literature although these are mostly static with no pre-loading. Axial pre-loading was found to change the dynamic characteristics of some cylindrical members quite dramatically while it had no significant effect on others. The study examined whether there was any change in the behaviour between local and global modes when the loading was dynamic rather than static. The effect of damping on the dynamic instability of axially pre-loaded tubes under lateral dynamic loads was also studied. It was observed that for some geometries the quasi-static response can be used to define the boundary between bounded and unbounded dynamic responses. The main contribution of this study, compared with previous investigations reported in the literature, is that both pre-loading and dynamic effects have been included. 相似文献