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211.
中国沿海星虫动物门名录 总被引:2,自引:0,他引:2
取1980~1989年间在我国沿海进行星虫动物区系调查的标本和有关资料做了整理、鉴定,共39种,分隶于2纲,4目,6科,12属。其中1种在我国为首次记录。 相似文献
212.
213.
用自装的BET容量法装置测定了几种粒状钛型吸附剂的比表面及其孔径分布。测定是在常温减压下进行的。结果表明:钛型吸附剂在加铀海水中的吸铀量与样品的比表面及孔径分布有一定的内在联系。这种表面性质的研究对吸附剂的筛选有重要的指导意义。 相似文献
214.
Representation of double-peaked sea wave spectra in Jiaozhou Bay 总被引:1,自引:0,他引:1
The spectrum shape characteristics of double-peaked sea wave spectia actually measured in the Jiaozhou Bay were analysed and one representation of double-peaked sea wave spectra with six-parameters which can be determined from a given sea wave spectrum is proposed in this paper. After verifying by fitting process with the data sets of double-peaked sea wave spectra measured in the Jiaozhou Bay, it can be seen from the results that the representation mentioned above may be used to express the double-peaked sea wave spectra generated in the Jiaozhou Bay under various sea states, and that the absolute values of maximum deviation index (D.I.) do not exceed 30. 0. 相似文献
215.
The relationship between tidal current field and sediment transport in the Huanghai Sea and the Bohai Sea 总被引:2,自引:0,他引:2
-Based on a two-dimensional numerical M2 tidal model of the Huanghai and Bohai Seas, sediment transport of particles with different sizes in the computational area is given. It is concluded that tidal currents play an important role in sediment transport and deposition in the Huanghai and Bohai Seas. 相似文献
216.
Study of zooplankton ecology in Zhejiang coastal upwelling system-Zooplankton biomass and abundance of major groups 总被引:1,自引:0,他引:1
He Dehu Yang Guanming Fang Shaojin Shen Weilin Liu Hongbin Gao Aigen Huang Shuxin 《海洋学报(英文版)》1988,7(4):607-620
The studied area is a shallow water area that belongs to the East China Sea continent shelf. The distribution of zooplankton biomass is higher inshore than offshore. The maximum abundance is in the inshore edge of the centre of upwelling, which is the superposed area of the salinity front and temperature front, due to the fact that the mixture of three different waters has brought about a concentration of nutrients. The herbivorous Euphausia, Copepoda and Tunicata are the major groups of the abundant area. Tunicata possess the possibility to compete against other kinds of herbivorous zooplankton. This means that there is negative correlation between the distribution of Tunicata and that of Copepoda and Euphausia. The positions of maximum areas of zooplankton biomass, phytoplankton individual and the concentration of phosphates and chlorophyll-a overlap one another. In the centre of upwelling, zooplankton can not adapt itself to the environment of lower temperature and less oxygen even with rich nutrient 相似文献
217.
Magnetic properties were measured on 370 vibrocores obtained from the outer continental shelf of the East China Sea, with
the aim of reconstructing environmental changes during the late Quaternary. High SIRM/χ values (>25 kA m−1) found in stiff muds of late Pleistocene age suggest the presence of magnetic iron sulfides, especially greigite. Framboidal
aggregates of greigite were further identified by scanning electron microscopy (SEM) and attached energy dispersive X-ray
(EDAX) analyses, as well as powder X-ray diffraction (XRD) analyses of the magnetic separates. The occurrence of magnetic
iron sulfides indicates the complex oxidation–reduction of the stiff muds, resulting from exposure and inundation during the
last glacial maximum (LGM) and the post-glacial transgression, respectively. 相似文献
218.
Cheng-Han Tsai Min-Chih Huang Fu-Ji Young Yin-Chern Lin Hsien-Wen Li 《Ocean Engineering》2005,32(10):4936-1259
Except the commonly selected pressure transfer function derived from the linear wave theory, a previous study on the pressure transfer function for recovering surface wave from underwater pressure transducer suggested that the pressure transfer function is a function of frequency parameter only. With careful analysis, this study showed that the pressure transfer function should include a transducer submergence parameter as that given by the linear theory. It was found that the previously suggested empirical formula should be restricted to measurements with the pressure transducer close to the surface; otherwise overestimation of wave height would result. Field measurements were carried out with an acoustic wave gauge and a synchronized pressure transducer located at various depths with submergence parameter close to 1 (near the sea floor). It was shown that the previous one-parameter empirical formula might overestimate the significant wave height by more than 30%. This study found that with deep-water wave bursts excluded, the transfer function based on the linear wave theory provided a fairly good estimation on the significant wave heights, with an average deviation of 3.6%. 相似文献
219.
印度洋东部金枪鱼延绳钓渔业研究--大眼金枪鱼(Thunnus obesus)的生物学特征 总被引:4,自引:0,他引:4
根据作者在印度洋东部海域的延绳钓生产实践,对渔获的大眼金枪鱼群体的群体构成、摄食、繁殖等基本生物学特征进行了初步探讨.结果表明,渔获群体由纯重10~115kg、叉长80~195cm个体组成,纯重与叉长关系式w=2.000×10-5×L2.969;渔获物以3~5龄个体为主,雄性个体所占比例明显高于雌性个体,且随年龄增长雄性个体所占比例逐步提高.鱼群在该海域产卵期较长,不同年龄组性腺发育节律有明显差异. 相似文献
220.
INTRODUCTIONDissolvedorganiccarbon (DOC)makesupthesecondlargestofthebioactivepoolsofcar bonintheocean ,secondtothelargestpoolofdissolvedinorganiccarbon .Theglobaldissolvedorganiccarbonpoolisestimatedtobe 6 85Gt,avaluecomparabletothemassofCO2 intheat mosphere (Hedges,1 992 ) .Thesizeofthereservoir,aswellasitsdynamics ,indicatesthatDOCplaysacentralroleintheoceancarboncycle .AsitrelatestogreenhousegasessuchasCO2 andassociatesclimatecycle ,oceanicDOCbiogeochemicalcycleshavebeenoneoftheh… 相似文献