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951.
StudiesonmarinenanodiatomsinFujiancoastalwatersofChinainwinter¥LiuShicheng;GaoYahuiandChengZhaodi(ReceivedDecember22,1994;acc... 相似文献
952.
为了探讨西太平洋暧地区热带波动的天气效应,利用1980年2-9月140°E日本静止卫星纬度时间剖面卫星云图,分析了5d和14d左右周期热带波动云的演变特征,井综合分析了14d周期的云系演变型式与流场的关系,为预报热带中期天气变化规律提供了依据;热带波动中30-60d大气低频振荡的云量变化最显著,北半球夏半年热带波动的天气压主要在10°N-0°,各半年在10°N-10°S,超过这个区域热带云量的港分布型式就有明显的变化。 相似文献
953.
本文研究了二层流体系统中波浪的衰减。上层为理想流体,下层为粘弹性Voigt体。导出了色散关系,计算了波浪衰减系数。对于粘性或弹性很大或很小的情况,导出了各种水深情况下近似的显式的衰减系数表示式。与精确的数值结果比较,近似程度很好。可供工程设计参考、使用。 相似文献
954.
StudyonthecharacteristicsofthemarineboundarylayerintheEquatorialPacific¥ZhangZiyuandZhouMingyu(ReceivedAugust21,1993;accepted... 相似文献
955.
马尾藻类是重要的经济海藻。自古以来,我国劳动人民就以马尾藻作为药材和食品;近几年来,随着医药工业的发展,马尾藻类不仅越来越广泛地用在医药上,而且成为提取褐藻胶、甘露醇、碘和氯化钾的重要工业原料之一。因此,弄清这类海藻的种类、分布和资源情况是有效地开发、利用马尾藻类海藻的前提。西沙群岛地处我国海防前哨,海洋植物资源很丰富,马尾藻类种类也较多,为了更好地开发利用西沙群岛的海藻资源,使其为祖国的社会主义建设和工、农、兵服务,中国科学院海洋研究所曾于1957年,1958年,特别是无产阶级文化大革命后的1975年,1976年前后四次对西沙群岛的海藻进行了调査,收集了大量的标本。在此基础上,我们对西沙群岛的马尾藻科海藻进行了较为系统的研究,本文仅是这项研究任务的一部分,以后将陆续整理发表。 相似文献
956.
The present note deals with the effects of seawater with different copper concentrations and pH values on the larvae of the barnacle Balanus reticulatus Utinomi. The results show that the higher the copper concentration and the lower the pH value in the seawater, and the more acute the toxicity. In the natural seawater of pH 8.1 the effective concentration EC_(50), i.e. the copper concentration causing 50%. larvae fail to attach, is approx- 相似文献
957.
The floating oil storage system has been proposed as a new facility for Strategic Petroleum Reserve (SPR) in China. Mooring is one of the key technologies to ensure the safety, reliability, and performance of the oil storage system. This paper describes the concept, analysis, design and reliability of the mooring system. For mooring system design of these oil vessels, analysis is essential of the behavior of the vessel in connection with mooring facilities of nonlinear resilience. A nonlinear mathematical model for analyzing a moored vessel is established and solved. Some results of numerical simulations are presented. Assessment of the safety regarding the mooring system in terms of failure probability is carried out. Another simulation model for calculating the failure probability of the mooring system is proposed. The design parameters that have an influence on the characteristics of the failure probability have been identified. The simulation results show that the mooring system has an annual reliab 相似文献
958.
C. K. Paull W. Ussler H. G. Greene R. Keaten P. Mitts J. Barry 《Geo-Marine Letters》2003,22(4):227-232
A sediment gravity flow descended through the axis of Monterey Canyon on 20 December 2001 at 13:35 Pacific standard time.
The timing of this event is documented by a current-meter package which recorded an 11.9-dbar pressure increase in less than
10 min and was found 550 m down-canyon from its deployment site, buried completely within a >70-cm-thick gravity flow deposit.
This event is believed to have started in less than 290 m of water because an instrument at this location was also lost at
the same time. A 178-cm core collected after the event from the axis of the canyon at 1,297-m water depth contained fresh,
greenish, chlorophyll-rich organic material at 32-cm sub-bottom depth, suggesting the event extended to this water depth.
The only trigger identified for this mass movement event appears to be moderate sea and surf conditions. Thus, gravity flow
events of this magnitude do not require an exceptional triggering event. 相似文献
959.
Molecular identification of bloom-forming species Phaeocystis globosa(Prymnesiophyta)and its dispersal based on rDNA ITS sequence analysis 总被引:3,自引:1,他引:3
Abstract-The colony-forming Phaeocystis species are causative agents of dense bloom occurrences incoastal waters worldwide. It is difficult to separate them because of the different morphologies associatedwith their colonial stages. In this study we applied molecular approaches to analyze the genetic variationof Phaeocystis globosa and Phaeocystis pouchetii from several geogrtaphic regions, and to assist in tracingthe dispersal of bloom-forming Phaeocystis species in coastal waters of China. The Sequences of the inter-nal transcribed sacers (ITS1 and ITS2) of rDNA and the 5.8S ribosomal RNA gene of Phaeocystisstrains were determined. Sequence comparison shows that P.globosa was the most divergent toP. pouchetii, exhibiting sequence divergence higher than 0.08. However, lower genetic divergences ex-isted between strains of P.globosa. The sequence comparison of the Phaeocystis rDNA ITS clearlyshows that the species isolated from the southeast coast of China is identified as P. globosa rather thanP. cf. po 相似文献
960.
Using benthic macrofauna to assess environmental quality of four intertidal mudflats in Hong Kong and Shenzhen Coast 总被引:4,自引:0,他引:4
Cai Lizhe Nora F. Y. Tam Teresa W. Y. Wong Ma Li Gao Yang Yuk-Shan Wong 《海洋学报(英文版)》2003,22(2):309-319
Abstract-Intertidal zone is a significant wetland between land and ocean. It plays an important rolein maintaining local ecological balance. Both Mai Po and Futian intertidal mudflats are located in Shen-zhen Bay and are important "refueling" point along the East Asian/Australian flyway of migratory birds.The environmental quality of Mai Po and Futian mudflats have aroused great concern due to rapid eco-nomic developments in Hong Kong and Shenzhen in recent decades. Microinfauna of Mai Po and Futianmudflats was investigated in December 2000 and the faunal data were used to assess their environmentalquality. Two other mudflats, namely Ma Wan Typhoon Shelter (a more disturbed area) and Luk Kengintertidal mudflat (a place with relatively less human disturbance), were also sampled for macroinfaunaand used as reference mudflats. Shannon-Weaver species diversity index (I_(sd)), biotic coefficient (C_b)and macrofaunal pollution index (I_(mp)) of the macrofauna community on four intertidal mudflats wereused to 相似文献