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41.
Aquasi-three-dimensionalnumericalpredictionmodelofsalinitystructureinBohaiSeaandHuanghaiSea¥SunWeiyangandWangZongshan(Receive...  相似文献   
42.
Chemical forms of Ba are determined in samples of suspension and sediment from the Zhujiang Estuary. Their interfacial geochemical processes are discussed. Total suspended Ba content is between 2. 4 and 40. 4 μg/L, and mostly exists in the crystalline form (43. 5%), secondly in the Fe-Mn oxidative form (23.1%). Percentages of organic, carbonate and exchangeable forms are 14. 8%, 11. l%and 7.4%, respectively. Total content of Ba in the sediment is between 158. 6 and 48. 0 ug/g. Percentages of crystalline form, Fe-Mn oxidative form and carbonate form are 78. 4% ,13. 5%and 8. 2%, respectively. Organic and exchangeable forms are not detected. The study on the mechanism of interfacial movement suggests that the salinity range of 10 is the turning point for the varied distribution of Ba. The subsidence of crystalline form affects the decrease of Ba content in suspension. The decrease mostly takes place in the salinity range lower than 10, which corresponds to the high value of Ba content in the sediment. The  相似文献   
43.
-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   
44.
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   
45.
Vertical variations of wave-induced radiation stress tensor   总被引:3,自引:0,他引:3  
INTRODUcrIONThe concept of radiation stress was deve1oPed by tonguet--Higgins and Stewart (1964 ),who intreduced the definition of radiation stress as the excess mornentum due to the presence ofwaves, on the basis of time-averaged laws of Newtonian fluid mechanics and the assmption ofa unifOrm velocity distribution over depth. Subequently, the theory has been applied success-fully in the investigation of phenomena such as wave set-up and set--down (Bowen et al.,l968), longshore currents …  相似文献   
46.
珠江三角洲晚第四纪沉积特征   总被引:8,自引:0,他引:8  
本文主要研究珠江三角洲的第四纪地层;晚更新世玉木亚间冰期、全新世中期(大西洋期)海侵阶段的地貌景观及珠江三角洲晚第四纪以来的沉积形成过程。  相似文献   
47.
黄河三角洲桩西101站潮沟地貌形态及其水动力学研究   总被引:6,自引:1,他引:6  
在潮沟下游,横跨且生趣与潮沟的横断面设了5个观测站,进行了24h的水动力测量。结果表明,涨落潮流速流向不对称,在潮沟内,涨落潮流流速差别很大,涨潮流流速最大为9cm/2,而落潮流流速最大可达38cm/s。据推测,潮沟内之所以落潮流流速明显大于涨潮流流速,可能是由于潮沟与岸线斜交有关。  相似文献   
48.
-Morphology, reproduction, ecology and isoenzyme electrophoresis of a Capitella complex in Qingdao were examined from 1983 to 1984. We determined that the Capitella complex in Qingdao was composed of at least three sibling species: Capitella cf capitata, Capitella sp. I and Capitella sp. IT. Although these three species are very similar in morphology, they differ in: three kinds of isoenzyme electrophoresis, staining reactions, developmental pattern, larval morphology and dispersal, reproductive strategies, breeding season and population ecology. In addition, they show a series of minor quantitative variations in adult morphology, especially in number and morphology of setae. Such differences can be detected only at the population level. Some ecological data such as density, growth rate, mortality and sex distribution are also provided in this paper.  相似文献   
49.
提要应用RNeasy animal mini试剂盒抽提大黄鱼total RNA,逆转录合成模板cDNA;同时综合分析从GenBank数据库查询到已报道的转铁蛋白(Tf)基因序列,先设计并合成扩增引物扩增出大黄鱼转铁蛋白部分基因序列,再应用RACE技术,克隆出大黄鱼转铁蛋白全长cDNA基因,全长2461个核苷酸,编码661个氨基酸。应用WCG软件包,采用DNADIST和NEIGHBOR分析方法,构建了转铁蛋白系统进化树。树图显示与传统的分类地位大致相符,可以看出转铁蛋白在海水鱼和淡水鱼的进化上的差异,同时也显示大黄鱼Tf与真鲷的同源性最高。  相似文献   
50.
综述了南海和台湾以东海域若干气旋型和反气旋型涡旋研究.在南海存在着许多活跃的中尺度涡,我们分别对南海中、南部海域和南海北部海域中尺度涡作了评述.在南海北部海域,目前最感兴趣的问题为:南海水与西菲律宾海通过吕宋海峡的交换的物理过程,以及黑潮是否以反气旋流套形式进入南海.这些问题目前尚不清楚,尤其是这些问题的机理.这些问题必须通过今后深入和细致的、长时间的海流和水文观测,以及长时间卫星遥感观测资料的论证才能逐渐认识清楚.台湾以东海域,黑潮两侧经常出现中尺度涡,而且变化较大而复杂.文中着重讨论兰屿冷涡和台湾东北的气旋式冷涡.  相似文献   
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