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维生素D对中国对虾生长影响的研究 总被引：4，自引：1，他引：4
于１９９０年７－９月用不同维生素Ｄ水平的饵料饲喂中国对虾，研究饵料中维生素Ｄ的适宜添加量及对对虾的营养作用。结果表明，每百克饵料中添加６０００Ｕ维生素Ｄ，其体长增长率和增重率最大，蛋白质消化吸收率最好，饵料系数最低；ＶＤ对对虾存活率无明显影响；投喂适量的维生素Ｄ时，有助于钙，磷在虾体中的吸收，虾壳中的沉积，虾壳的硬化。 相似文献
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β-蜕皮激素和水龙骨素B的混合物对促进对虾蜕皮生长的作用 总被引：8，自引：0，他引：8
本文采用了对虾Penaeus orientalis人工配合饵料中添加蜕皮激素混合物的方法,试验β-蜕皮激素和水龙骨素B(2:1)的混合物促进对虾蜕皮生长的作用.经实验证明:饵料中添加蜕皮激素1.33-30μg/g,均可不同程度地促进蜕皮生长,然而以每克饵料添加5.33-10.67μg较为显著.相反,若含量达到60μg/g就会抑制对虾蜕皮生长,乃至中毒.食用添加蜕皮激素混合物(10.67μg/g)的饵料促进蜕皮生长的虾,其水分、灰分及蛋白含量,经测定无明显差异. 相似文献
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中国对虾幼体发育阶段维生素A营养需要的研究 总被引：5，自引：0，他引：5
１９９６年５月１１日－６月１３日中国在水产科学研究院黄海水产研究所麦岛实验基地采集中国对虾幼体,在其配合饵料中添加维生素Ａ,对其发育阶段维生素Ａ的营养需要进行研究。结果表明,配合饵料中维生素Ａ的含量为４０．１６－６．１５μｇ／ｇ时,对中国对虾幼体的变态,成活和健康有明显的促进作用。 相似文献
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中国对虾配合饵料添加维生素的效果 总被引：1，自引：0，他引：1
将维生素作为一个综合指标加以试验,配备5个不同维生素水平(0,0.27,0.54,1.1,2.1％)的饵料试验组,经较长期的室内饲养试验以考察混合维生素对对虾生长和成活率的影响。结果表明,在试验范围内,随着添加维生素份量的增加,对虾的成活率也增高,增重倍数也提高。这就表明,维生素(在试验范围内)有降低对虾死亡率、促进生长的作用。维生素促进生长的效应最敏感区间是0～0.54％,在此范围内,维生素的少量增加也能明显地提高其生长效果,而维生素在1.1～1.2％范围内,增重曲线就逐渐趋向平坦,表示2.1％的添加量接近维生素的最适添加量。 维生素还有降低饵料系数的作用,在试验范围内,随着维生素的增加,饵料系数也降低,最低可达2.48。 相似文献
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甜菜渣对中国对虾消化酶的影响研究 总被引：3，自引：0，他引：3
于１９９６年１０月在中国科学院海洋研究所选取人工养殖中国对虾（平均体长９．０２ｃｍ），以双缩脲法测定消化器官的蛋白含量；福林一酚试剂法测定蛋白酶活力；Ｓｏｍｏｇｙｉ比色法糖法测定淀粉酶和纤维素酶活力，同时研究中国对虾配合饵料中添加１０％的甜菜渣或１０％经不同方法处理的甜菜渣时，对消化器官蛋白酶、淀粉酶、纤维素酶活力变化的影响。结果表明，在饵料中添加１０％甜菜渣 经不同方法处理的甜菜渣饲喂中国对虾， 相似文献
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牟氏角刺藻(Chaetoceros muelleri)是鱼、虾、贝、海参等幼体的优良饵料。特别是在对虾(Penaeus orientalis)人工育苗中,其饵料效果更为优越。投喂本藻,对虾溞状幼体可以顺利地变态到糠虾期,而无需添加轮虫(Rotaria spp.)等动物性饵料,成活率可达85％,与投喂三角褐指藻(Phaeodactylum tricornutum)相比,可提前 4—5天发育至糠虾期,平均成 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