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401.
402.
闽南近海常见鲨鳐类肝油的四种理化常数和角鲨烯含量 总被引:8,自引:0,他引:8
本文分析测定了闽南近海常见鲨鳐类肝油的理化常数和角鲨烯含量。尖头斜齿鲨肝油的碘值特别高,说明其中脂肪酸的不饱和程度很高;非皂化物含量很低,约占肝油重的38×10-3(m/m);角鲨烯含量极微,在肝油中仅占84×10-5(m/m)。闽南近海常见鲨鳐类肝油的角鲨烯含量均很低,变化在(31~116)×10-5(m/m)之间。在相同的气相色谱条件下,小孔沙条鲨和狭纹虎鲨肝油中没有检测到角鲨烯。 相似文献
403.
Wang Deyu Zhang Shanyuan
Associate Prof. Depart of Naval Archi. Ocean Engineering Shanghai Jiaotong University Shanghai
Prof. Research Institute of Applied Mechanics Taiyuan University of Technology Taiyuan 《中国海洋工程》1996,(2)
- The shear failure of a rigid-plastic dented clamped tubular beam under the lateral impact of a mass is investigated. Both the denting and the impact point are in the middle span of the beam. It is assumed that denting does not spread during the shear sliding. Numerical results show that the axial force and lateral deflection of the beam are very small at the moment of the occurence of shear failure, which means that the finite deformation effect can be neglected in the shear failure analysis. Also, some aspects of the initial impact energy are investigated. 相似文献
404.
Channels of cross - equatorial flow and their characteristics Winds at every 5 deg. grid point from 30°E to 180° over the equator at 850 hPa and 200hPa from December 1984 to February 1985 have been separated into U(zonal wind) andV(meridional wind).The V component has been used to represent cross- equatorial flow. FromFig. 1 we obtained that as during the Northern summer,there are also severa1 regions in which 相似文献
405.
Tan Jiahua Ma Wei Pan Bin Associate Professor Shanghai Jiao Tong University Shanghai Lecturer shanghai Jiao Tong University Shanghai 《中国海洋工程》1992,(1)
The basis, process and results of the demonstration of the main dimensions of a 75000t floating production and storage vessel are discussed in this paper. A simple but reliable orthogonal design method is applied in the main dimension optimization. The ideas of gradual approximation and feedback from various aspects are put into effect. During the demonstration, in order to make the model tally with the actual situation, the draft design is closely related to the computational analysis, so that the demonstration model can be verified at any time; the handling of the overall system is closely related to the research of each item, which is beneficial not only to the mastery of various regularities, but also to the balance of decisions. Finally, according to the computational results and the regularities obtained from analysis, the main dimensions are determined. 相似文献
406.
Liu Jiaju Zhang Jingchao Prof. Senior Engineer River Harbour Department Nanjing Hydraulic Research Institute Nanjing Senior Engineer River Harbour Department Nanjing Hydralulic Research Institute Nanjing 《中国海洋工程》1992,(2)
- This paper, after briefly reviewing the experimental research on sediment transport on muddy beach since the 1950s, improves and perfects the method for forecasting siltation in navigation channels and harbour basins which was first put forward in China by the authors. In consideration of silty sediment and sand, some factors in forecasting methods have been changed and modified. Consequently, the modified methods can be used either to compute siltation in navigation channels and harbour basins on muddy beach or to compute siltation and scouring in navigation channels and harbour basins on both silty beach and sandy beach. The verification of field data from eleven large, medium and small natural harbours shows a good agreement between the forecasting by the modified method and the natural conditions. Finally, the paper deals with the rational utilization of water area after the construction of the West Dyke in Lianyungang, the maintenance of water depth of the navigation channel at the entrance, siltation distribution, siltation in the navigation channel and harbour basin for ships of 100 thousand tonnnage. Results once again prove that the prospect of constructing Lianyungang Harbour into a deepwater harbour is bright. 相似文献
407.
华南三水盆地白垩纪—早第三纪古纬度漂移与南海演化 总被引:1,自引:0,他引:1
本文主要依据三水盆地古地磁数据所反映的华南地块的古纬度漂移讨论南海的演化模式。结果认为,华南在南海的形成演化中居主导地位,南海基本上是晚白垩世至中新世期间通过华南的南漂及其后的北向回漂过程中,华南大陆南部的拉张、断裂、解体并自东向西扩展的方式形成的,而南海中散布的微大陆碎块则是在华南回漂时被滞留下来的。演化过程中,其周缘菲律宾岛弧自南向北漂,直到上新世后才构成南海的东界;印支地块则仅起转换边界作用;加里曼丹则基本土没有明显的漂移。 相似文献
408.
A study on zooplankton distribution patterns and indicator species in Kuroshio upstream area and adjacent East China Sea 总被引:3,自引:0,他引:3
On the basis of the data of zooplankton biomass and three major taxa—— Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of zooplankton in the Kuroshio and adjacent waters of the East China Sea are preliminarily studied. The results are as follows:The horizontal distribution of zooplankton biomass and the abundance of copepods, chaetognaths and siphonophores arecurred in the continent area northwest of Taiwan and the south-centre section of the East China Sea continent, which are the mix front of different waters. Zooplankton in the water area inside of Ryukyu Islands presented low abundance and high diversity. There are clear seasonal variations in zooplankton biomass and abundance in the study area. The strength or weakness of different water masses and fronts is the basic reason for the variations of zooplankton biomass and abundance.The species composition of zooplankton in the study area is complex and var 相似文献
409.
中国对虾体内20-羟基蜕皮酮含量与生长和性腺发育的关系 总被引:3,自引:0,他引:3
应用放射免疫分析法对完成变态后的中国对虾(Penaeus orientalis)体内20-羟基蜕皮酮(20-HE)含量进行了周年测定。5~6月,全虾抽提液中20-HE的质量分数以体长为0.8cm的仔虾为最高(47.96±3.94)×10~(-9)(m/m)。血淋巴中20-HE的质量浓度在6~8月(平均为22.66ng/mL)和11月(25.93±3.44ng/mL)较高,翌年3月最低,为8.29±1.40ng/mL。呈现出20-HE含量与蜕皮生长和促进卵母细胞早期发育及精子发生有关。 相似文献
410.
本文根据南海深海盆地三个沉积柱样的粒度结构、地球化学、微体古生物等特征分析,深讨了南海深海盆地细粒沉积物的浊积现象。结果表明,位于南海北部陆架斜坡上KL37孔的浊流沉积现象并不明显;位于陆架斜坡和深海盆地交界处的KL29孔存在着大量的浊积层,属于浊流沉积和半远洋沉积环境;位于南海盆地中部的KL91孔虽然已属于远洋性沉积环境,但除出现火山灰沉积外,浊流沉积作用仍然是相当活跃的。 相似文献