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1.
日本新任首相安倍晋三于2006年10月8日访华。他就任后第一次出访就到中国,说明很重视与中国和亚洲的外交关系,旨在改变小泉时代留下的政治后遗症——中日关系冷淡,日本亚洲外交危机。安倍访华期间中日发表联合公报,其内容包括坚持东海磋商,加快共同开发步伐,寻求双方都能接受的方案等。安倍访华标志着中日紧张关系开始缓和,但并不等于中日东海问题就此迎刃而解。中日东海问题是长期形成的,错综复杂的,不可能通过一两次首脑访问就能解决根本问题,充其量只能起到遏制势头恶化的作用。以笔者之见,在东海问题上日方仍然掌握着主动权,海上保安厅出动武装舰船和飞机始终控制着我国固有领土——钓鱼岛及其周边海域。至今没有任何迹象表明日本政府要收回授权民间企业在东海试开采的成命,强行试钻的可能性依然存在。中日双方虽然就东海共同开发达成继续进行磋商的一致意见,但从发展趋势分析最终仍有利日方。  相似文献   

2.
The traction capacity of the mining machine is greatly in?uenced by the traction rheological properties of the deep-sea sediments. The best simulative soil was prepared for substituting the deep-sea sediment based on the deep-sea sediment collected from the Paci?c C-C mining area. Traction rheological properties of the simulative soil were studied by a home-made test apparatus. In order to accurately describe the traction rheological properties and determine traction rheological parameters, the Newtonian dashpot in Maxwell body of Burgers model was replaced by a self-similarity spring-dashpot fractance and a new rheological constitutive model was deduced by fractional derivative theory. The results show the simulative soil has obvious non-attenuate rheological properties. The transient creep and stable creep rate increase with the traction, but they decrease with ground pressure. The fractional derivative Burgers model are better in describing non-attenuate rheological properties of the simulative soil than the classical Burgers model. For the new traction rheological constitutive equation of the simulative soil, the traction rheological parameters can be obtained by ?tting the tested traction creep data with the traction creep constitutive equation. The ground contact length of track and walking velocity of the mining machine predicted by the traction rheological constitutive equation can be used to take full advantages of the maximum traction provided by the soil and safely improve mining effciency.  相似文献   

3.
中国沿海中华白海豚种群的分布区   总被引:1,自引:0,他引:1  
中华白海豚Sousa chinensis(Osbeck,1765)首先在我国发现,是我国沿海仅有的定居性海洋鲸豚类.本文根据中华白海豚目击事件和研究报道,分析了中华白海豚在中国的分布、种群隔离及其差异.认为我国南方福建、广东以南沿海为中华白海豚种群的主要分布区,明确指出我国沿海存在5个主要的中华白海豚种群栖息地.通过分析,划分出中华白海豚活动的边缘区和栖息地两个部分.由于中华白海豚种群不断缩小,在保护中华白海豚栖息地的基础上,加强对中华白海豚栖息地外的边缘区的保护显得尤为重要.本文分析将为科学划定中华白海豚保护区提供依据.  相似文献   

4.
Liu  Heng-xu  Liu  Ming  Chai  Yuan-chao  Shu  Guo-yang  Jing  Feng-mei  Wang  Li-quan 《中国海洋工程》2019,33(3):279-287
This paper mainly describes the influence factors of the captured energy power by huge wave energy harvesters, in which the vertical motion of buoy can transform ocean’s potential energy into piezoelectric energy power by undulating waves. Firstly, related environmental coefficients are analyzed by means of the incident wave theory. Besides, the geometric structural parameters are also analyzed and compared under optimal environmental coefficients with semi-analytical solutions. Thirdly, the numerical results also show the impact trend of hydrodynamic parameters and geometric volume on motion, voltage and power with qualitative agreement. The numerical simulation confirms that the improved structure parameters could markedly deliver sufficient power under the same conditions with long-time stability.  相似文献   

5.
Reducing the cost of offshore platform construction is an urgent issue for marginal oilfield development.The offshore oil well structure includes a riser and a surface casing.The riser,surface casing and oil well cement can be considered special variable cross-section piles.Replacing or partially replacing the steel pipe pile foundation with a variable cross-section pile to provide the required bearing capacity for an offshore oil platform can reduce the cost of foundation construction and improve the economic efficiency of production.In this paper,the finite element analysis method is used to investigate the variable cross-section bearing mode of composite piles composed of a riser and a surface casing in saturated clay under a vertical load.The calculation formula of the bearing capacity at the variable section is derived based on the theory of spherical cavity expansion,the influencing factors of the bearing capacity coefficient Nc are revealed,and the calculation method of Nc is proposed.By comparing the calculation results with the results of the centrifuge test,the accuracy and applicability of the calculation method are verified.The results show that the riser composite pile has a rigid core in the soil under the variable cross-section,which increases the bearing capacity at the variable cross-section.  相似文献   

6.
赖其良  袁军  邵宗泽 《台湾海峡》2008,27(2):141-146
以印度洋深层海水,用柴油和石油作为混合碳源经富集培养、分离获得一株具有很强的柴油降解能力的茵株P40.茵株P40革兰氏染色阴性,接触酶和氧化酶为阳性,能还原硝酸盐,不能还原亚硝酸盐.16S rDNA Blastn 结果表明其与 Alcanivorax dieselolei B-5T(柴油食烷茵)及 A.dieselolei NO1A具有最高相似性,均为99.8%.茵株P40的gyrB序列与 A.dieselolei NO1A同源性也高达99.2%.而与A.dieselolei B-5T只有86.9%.此外,从茵株P40中克隆到两个烷烃羟化酶alkB基因片断,分别命名为P40-alkB1和P40-alkB2.其中P40-alkBl与报道的 A.dieselolei B-5T 中的 alkB 同源性较高,达96.3%,而与同为深海来源的茵株NO1A的alkB的同源性更是达100%,P40-alkB2则与A.borkumensis SK2T(泊库岛食烷茵)的alkB1同源性最高,但仅为65%.  相似文献   

7.
8.
6月8日,2011年世界海洋日暨全国海洋宣传日主场活动在辽宁省大连市隆重开幕,今年活动的主题是辛亥百年,海洋振兴。全国人大常委会副委员长周铁农出席庆祝大会并宣布2011世界海洋日暨全国海洋宣传日活动开幕。国家  相似文献   

9.
保障渔民合法权益是深化海洋管理工作面临的重要课题   总被引:2,自引:0,他引:2  
舟山是我国唯一以群岛设立的地级市,区域总面积2.22万km2,其中海域面积2万hm2余,“港、景、渔”等海洋资源十分丰富,是名副其实的海洋大市。  相似文献   

10.
11.
An attempt has been made to estimate the fishery potentials of the EEZ of India on the basis of data on primary and secondary production. The total column primary production and zooplankton production have been calculated to be 265·9 and 9 million tonnes of carbon per year, respectively. From these values the fishery potential has been estimated as 2·5 million tonnes per year. To this, if we add the estimated demersal fish catch, being 1·2 million tonnes per year, the total potential yield comes to 3·7 million tonnes per year. Since the present average total catch is about 1·6 million tonnes in a year, the fish catch could be doubled.  相似文献   

12.
介绍了海鸟系列温盐深测量仪(CTD)原始数据预处理的方法和步骤,解释各个过程中的原理,根据规范和工作实际对处理过程中存在的问题进行分析,提出解决方案,针对资料的标准化提出建议和意见。  相似文献   

13.
文章讨论了波浪场可视化实现过程中的一些关键的算法。文中针对表示波浪面的数据集的特性,采用了一种简单的节点法矢量算法。绘制结果表明,用这种简单算法取代二维和三维的数据场节点法矢量的常用算法,能够保持波浪场三维图形的光照效果。利用层次模型算法进行波浪的动态演示,比较了相同面积的波浪场在不同网格密度情况下图形的显示质量,提出波浪场图形质量有与特征波长相匹配的最佳经验网格密度。  相似文献   

14.
光辐射对海洋微藻脂肪酸含量的效应   总被引:7,自引:0,他引:7  
不同光辐射强度下三角褐指藻和小球藻脂肪酸的气相色谱分析表明 ,光辐射对海洋微藻脂肪酸的含量和组成影响很大。三角褐指藻和小球藻总多不饱和脂肪酸含量随着照度的增加呈下降趋势。在本实验条件下 ,在较低光强 (0 .2 5× 10 3 L ux~ 1.7× 10 3 L ux)时 ,EPA、DHA、C18∶ 3等多不饱和脂肪酸含量较高。  相似文献   

15.
乐清湾水域纳潮量演变分析   总被引:2,自引:0,他引:2  
基于1965年以来的不同时期水深地形数据和卫星遥感影像资料,对乐清湾岸线和不同特征值水深所围水域面积的历史变化进行研究,根据GIS技术计算乐清湾近50年的不同水域面积的演变特征。利用实测地形资料和水文数据建立乐清湾海域二维潮流数学模型分析乐清湾水域纳潮量的演变情况。结果表明:(1)乐清湾海域纳潮量近50年减少3.16×10~8 m~3,2013年较1965年减少17.69%,年均递减速率由0.06×10~8 m~3/a增加至近年的1.96×10~8 m~3/a;(2)海湾不同区域围填海造成相应海区水域面积的缩减,但纳潮量对水域面积改变的响应程度有显著差别。内湾滩涂围垦对乐清湾不同湾区纳潮量影响十分有限,外湾围垦对纳潮量的影响由外湾向内湾明显递减。漩门湾二期工程显著改变乐清湾的潮流形态,造成各个湾区纳潮量均出现大幅度的调整。本研究可以为海湾的生态环境保护和预测海湾的发展趋势提供量化的参考数据。  相似文献   

16.
本文对近年来蓝藻基因组研究进展进行了综述.介绍了聚胞藻PCC6803基因组研究方法和成果,包括最佳分析软件的选择,所获得的基因组基本信息,以及后基因组研究的部分成果.蓝藻基因组间差异很大,文中介绍了其它蓝藻基因组的基本信息和在各个藻种里的重要发现.文章最后探讨了蓝藻基因组的研究意义和前景.  相似文献   

17.
牡蛎肉提取物主要营养成份的分析   总被引:10,自引:0,他引:10  
陈荣忠  杨丰  王初升 《台湾海峡》1999,18(2):195-198
牡蛎肉中含有丰富的糖元、牛磺酸以及微量元素锌等。牡蛎肉提取物的氨基酸通过 HPLC分析,表明含有丰富的牛磺酸(7%);经 酮比色定糖法测定其糖元含量为 14.5%;石墨炉原子吸收法测得其锌含量为 89. 5 × 10~-6(m/m)。牡蛎肉在保健补品方面能起到陆源食品所不能代替的独特作用。可以预言,牡蛎肉将作为开拓保健补品的新资源。  相似文献   

18.
Stomach contents of 68 black petrels, Procellaria parkinsoni, 12 Westland black petrels, P. westlandica, and 3 white‐chinned petrels, P. aequinoctialis, were compared. The main prey were Cephalopoda and fish, and these indicated predominantly nocturnal feeding with selection for bioluminescent forms. There is marked latitudinal variation in the Cephalopoda available to these petrels.  相似文献   

19.
尹朝阳 《海洋测绘》2005,25(3):74-75
影像地图的编制方法、内容展现有别于线划地图。较详细地介绍了《南京市老城区影像图册》比例尺、开本选择、影像编辑处理、图面内容要素表示、计算机编图的方法和手段。  相似文献   

20.
We examine the processes underlying the generation and propagation of the small meander of the Kuroshio south of Japan which occurs prior to the transition from the non-large meander path to the large meander path. The study proceeds numerically by using a two-layer, flat-bottom, quasi-geostrophic inflow-outflow model which takes account of the coastal geometries of Kyushu, Nansei Islands, part of the East China Sea, and the Izu Ridge. The model successfully reproduces the observed generation and propagation features of what is called "trigger meander" until it passes by Cape Shiono-misaki; presumably because of the absence of the bottom topography, the applicability of the present numerical model becomes questionable after the trigger meander passes by Cape Shiono-misaki. The generation of the trigger meander off the south-eastern coast of Kyushu is shown to be associated with the increase in the supply of cyclonic vorticity by the enhanced current velocity in the upper layer along the southern coast of Kyushu where the no-slip boundary condition is employed. Thereafter, the trigger meander propagates eastward while inducing an anticyclone-cyclone-cyclone pair in the lower layer. The lower-layer cyclone induced in this way, in particular, plays a crucial role in intensifying the trigger meander trough via cross-stream advection in the upper layer; the intensified trigger meander trough then further amplifies the lower-layer cyclone. This joint evolution of the upper-layer meander trough and the lower-layer cyclone indicates that baroclinic instability is the dominant mechanism underlying the rapid amplification of the eastward propagating trigger meander.  相似文献   

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