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101.
Sediment and porewater data of two sediment cores from offshore southeastern Taiwan show important effects of the complex sea floor topography upon carbonate and organic carbon deposition. The variations in carbonate and organic carbon contents are attributed to the effects of carbonate compensation depths, glacial-interglacial history, and condition of anoxia. The study is of significance for environmental reconstruction and petroleum source bed evaluation of ancient analogues. 相似文献
102.
The data of about 1700 drill holes are correlated, of which 47 drill sections are discussed comprehensively for chronology and sedimentology, and the characteristics and changes of sporo-pollen are analysed. The authors consider that the Holocene strata along the coast of eastern Guangdong can be divided into five formations. The Holocene began 12 000 years ago; the fluvial facies gravel, the striped weathered clay and the "old red sand" serves as the boundary between the Holocene and the Pleistocene. 相似文献
103.
分析1980-1987年欧洲中长期预报中心(ECMWF)每日风场、温度场格点资料及同期南海区域测站和船舶资料,讨论南海低层风场的气候特征。南海为典型的季风活动区,冬季盛行东北季风,夏季盛行西南季风。流场的季节转换表现为季风系统的交替,相应不同的季风系统,南北温度梯度有一逆转过程,南海北部是温度梯度大且发生明显逆转的海区。12°N以南海区气温全年变化极小,整个海区大气温度的季节变化不如流场变化快和显著。 相似文献
104.
鳗鲡气单胞菌引起的烂尾病病原菌抑菌药物的研究 总被引:5,自引:0,他引:5
应用药敏纸片法研究了三株烂尾病病原菌(气单胞菌)对31种药物及不同配合药物的敏感性,测定了4种药物及配合药物HP对三株菌的最低抑菌浓度(MIC)及最低杀菌浓度(MBC)。结果表明,配合药物HP具较强的抑菌能力。 相似文献
105.
In this paper further mathematical analysis on "correlation transfer technique" by Polge el al. is carried out, the tenable conditions and the extent of suitability for the said method are proved as well. In consideration of the influence of skewness of the sea surface elevation on spectral shape, a "quasi-correlation transfer techique" is developed by the modification of the simulated target spectrum. Meanwhile, the numerical simulation of the non-Gaussian process of wind waves is carried out in view of the two conditions of the surface elevation probability distribution and the spectrum. By using its simulated results, the influence of skewness of the sea surface elevation on two parameters in the distribution of wave heights (which had been fitted by using the Weibull distribution) is analysed. The "quasi- correlation tranfer technique" is verified and compared with the selection wave data observed in the Jiaozhou Bay in the period of 1980 to 1981. Results make clear (hat, as far as the statistical d 相似文献
106.
This article introduces the most advanced form of electronic chart display and information systems (ECDIS) which complies with the performance standards for ECDIS established by the International Maritime Organization (IMO) and International Hydrographic Organization (IHO). It also describes the key features and the important functions of ECDIS, which we developed. This system is different from the productions developed by C-map, Seven-cs, offshore, and others. It is more suitable for China Marine Safety Administration Bureau to manage the navigation marks real-time. Using this system charts were located and accessed rapidly, and displayed smoothly. This article also discusses in ECDIS application system how to dynamically access and desert charts data in a limited memory (limited computer memory and resource). We constructed a tridimensional structure to manage a large amount of charts data. Vertically, according to the scale range, all charts were divided into eight levels, and a data structure called as “Multiple Scale Quad-tree” was constructed. And horizontally, a grid (every unit has a fixed size) was given to a certain scale level. We call this data structure a “Regular Page.” We explore the implementation of such a structure on the worldwide charts management utilizing quad-trees. Then we discuss the future development of ECDIS and its application system in marine agencies in China. 相似文献
107.
Bin Zhao Yong Yang Gaowen He Heng Zhang Weilin Ma 《Marine Georesources & Geotechnology》2020,38(9):1037-1045
AbstractCobalt-rich crust has attracted increased attention due to their economic value. Studies have indicated that seamounts in the Western Pacific Ocean are rich in cobalt-rich crust resources. The Caiwei Guyot in Western Pacific Ocean is one of the cobalt-rich crust exploration areas contracted between China and the International Seabed Authority. A large volume of research has been conducted to elucidate the tectonic evolution, basement type, sediment type, gravity and magnetic anomaly characteristics, and geochemical characteristics of shallow surface sediments at Caiwei Guyot. However, a research gap exists on the sedimentary strata below the pelagic deposits and above the volcanic basement of the Caiwei Guyot. This paper summarizes that two main types of sediments existing on the top of Caiwei Guyot. The deposition thickness on the top of Caiwei Guyot is characterized by three sedimentary centers and exposed periphery. Pelagic sediments are difficult to form at the northeastern portion and edge area of Caiwei Guyot due to the strong bottom current environment, which makes these areas suitable for crust growth. This paper delineated three cobalt-rich crust prospective areas at the Caiwei Guyot with of significant implications for exploration and mining-lease-block selections at Caiwei Guyot. 相似文献
108.
本文以9414、9415号两个连续北上台风为例,证明能量场的分布与台风移向有着明显的对应关系。 相似文献
109.
110.
样品于1986年11月至1987年10月在福建省罗源湾10个站位采集。经鉴定有52种水母。它们可分为沿岸暖水、沿岸暖温和大洋广布三种生态类群。水母类总数量和种类数的季节分布呈单周期,两者高峰均出现在7月。低谷分别出现于11月和1月。在平面分布上,以拟细浅室水母Lensia subtiloides占优势的月份,数量从湾口向湾顶递减,而以球型侧腕水母Pleurobrachia globosa占优势的月份,数量却递增。文中还讨论了水母类的分布和环境因素的关系。 相似文献