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1.
我们发现的四方硅铁矿与自然硅连生体矿物，产于山东莱州湾东部与金矿有关的片麻岩中。该矿物为灰黑色，强金属光泽，不透明矿物。四方硅铁矿的显微硬度：ＨＶ＝６８２．３Ｎ／ｕｍ￣２．自然硅的显微硬度：ＨＶ＝７０７．６Ｎ／ｕｍ￣２。电子探针分析：四方硅铁矿，Ｓｉ－５２．８８％，Ｆｅ－４４．８％，自然硅，Ｓｉ－９７．３３％。主要Ｘ射线粉晶分析谱线数据：四方硅铁矿，５．１５（１０），２．３８２（６），１．８５５（８），１．７８（３），１．３４３（１），自然硅，３．１３６（１０），１．９１０３（５），１．６３８（３）。晶胞参数：四方硅铁矿，Ａｏ＝２．２６８５人，Ｃｏ＝５．１３７人，Ｖｘ＝３７．０３４，Ｚ＝１，自然硅Ａｏ＝５．４２，Ｖｘ＝１５９．２２，Ｚ＝８。 相似文献
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深部地壳反射的双程走时在６～２０ｓ之间,特征为信噪比低、频率低（５～３０Ｈｚ）。要想获得最优化的反射信号要求如下：１;震源能量集中在这个频段;２;检波器排列尽可能长;３;炮间距尽可能短。用一个气枪阵列模拟程序来观察一个由１０枪组成的枪阵在不同深度发射时的效果。实验证明：将同一枪阵沉放到２５ｍ深处,可以增强低频端震源能量,此时深部反射层的信噪比比枪阵沉放深度为７．５ｍ的提高一倍,只是其纵向分辩率有所 相似文献
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用磁化水培养等鞭藻3011的初步研究 总被引：6，自引：0，他引：6
本文主要报道不同磁场强度的磁化水对等鞭藻繁殖作用的影响。１材料和方法安排５组磁场强度，分别为０．０５，０．１，０．３，０．６，０．９Ｔ，一个对照组。５０００ｍｌ的三角烧瓶６个。对海水进行沉淀、沙滤、陶瓷过滤，经磁化水器后，即为磁化水（不煮沸），尔后加入营养盐ＮａＮＯ３６０ｍｇ；ＫＨ２ＰＯ４４ｍｇ；ＦｅＣ６Ｈ５Ｏ０．５ｍｇ；ＮａＳｉＯ３５ｍｇ；ＶＢ１１００ｕｇ；ＶＢ１２０．５ｕｇ；溶于１０００ｍｌ海水中煮沸。室温１５～１８．５℃，光照２４０～２１６０１Ｘ，每天２４ｈ，，培养期间每天搅瓶６次。每天上… 相似文献
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利用南麂海洋站１９８１－１９９０年实测波浪资料，探讨了该海域风浪的平均波陡与平均波龄的统计分布特征。分析结果：当风浪平均波陡介于０．０２－０．０４时，其出现频率各季在８２％以上；当风浪平均波龄介于０．５－１．２时，其出现频率各季在７８％以上；当风浪的平均波陡与平均波龄介于０．０２－０．０４和０．５－１．０时，其出现频率为５３．５％－６９．６％。 相似文献
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罗非鱼球状囊微音器电位是一个双峰波。峰频与刺激声频成２：１关系；在２０－８０Ｈｚ电位波形不规则。在３００－９００Ｈｚ电位波呈矩形。实验表明，球状囊不同区域对一一的声频敏感性不一样；延脑－脊髓连结处的诱发电位与球状囊微音器电位相似，但在１３０Ｈｚ电位呈单峰波；罗非鱼可闻频域在２０－９００Ｈｚ，最大敏感声频在１３０Ｈｚ，其相对敏感性为２３．０１ｄＢ；延脑－脊髓连接处诱发电位最大值在６３Ｈｚ和１３０Ｈｚ 相似文献
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北隍城潮汐、波浪特征是：潮汐为正规半日潮，年平均海平面２４２ｃｍ，平均潮差１２７ｃｍ海浪以风浪为主，频率为９９％，涌浪频率为６３％，多年各月平均浪高０．４－１．７ｃｍ周期为３．３－５．４ｓ。 相似文献
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用逆转录聚合酶链反应检测草鱼出血病病毒的研究 总被引：3，自引：1，他引：3
于１９９４年５月－１９９５年７月，根据已克隆的草鱼出现血病病毒ＧＣＨＶ－８６１株ｃＤＮＡ的部分序列，设计合成了两对ＰＣＲ引物，采用ＲＴ－ＰＣＲ技术对ＧＣＨＶ－８６１ＧＣＨＶ－８７３两病毒株的ｄｓＲＮＡ进行扩增，结果表明，两对引物仅能特异地检测了ＧＣＨＶ－８６１病毒株核素的存在，而不能对ＧＣＨＶ－８７３病毒株的核酸进行特异扩增，该方法是最小可检测出０．１ｐｇ纯化的ＧＣＨＶ－８６１病毒ｄｓＲＮＡ，采用 相似文献
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晚麦斯特里希特期—早丹麦期高分辨率海洋８７Ｓｒ／８６Ｓｒ记录：白垩纪—第三纪之交事件的意义Ｈ．Ｂ．Ｖｏｎｈｏｆ等Ｋ—Ｔ交界短期８７Ｓｒ／８６Ｓｒ正异常是Ｈｅｓｓ等（１９８６）首次从Ｋ—Ｔ过渡期基准曲线中辨别出的，此后几次调查对此进行进一步探索，得出的... 相似文献
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在遥控深潜器（ＲＯＶ）上进行的深海甲烷水合物形成的野外试验ＰｅｔｅｒＧ．Ｂｒｅｗｅｒ等天然气中的格状水合物，是甲烷与水分子以１：５．７５的理想克分子比值结合的物质，具有冰状结构，五角十二面体几何形状，是浅海岩石圈的普通成分。气态水合物形成的现象是上世... 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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Derek V. Ellis 《Marine Georesources & Geotechnology》2001,19(1):51-63
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested. 相似文献
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G. Parthiban 《Marine Georesources & Geotechnology》2000,18(3):223-235
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement. 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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The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments. 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,(11):161-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