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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.
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   

3.
4.
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   

5.
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   

6.
The performance of dual perforated floating plates in a rectangular tank is investigated based on the model tests under different external excitations for different filling rates.It is found that dual perforated floating plates in the tank can remarkably mitigate violent resonant sloshing responses compared with the clean tank,especially when the external excitation frequency is in the vicinity of the first-order resonant frequency.Next,the parametric studies based on different filling rates and external excitation amplitudes are performed for the first-order resonant frequencies.The presence of dual perforated floating plates seldom shifts the sloshing natural frequencies.Further,dual perforated floating plates change the sloshing modes from the standing-wave mode in the clean tank to the Utube mode,which can arise from the sloshing reduction to some extent.  相似文献   

7.
The ice resistance on a ship hull affects the safety of the hull structure and the ship maneuvering performance in icecovered regions.In this paper,the discrete element method(DEM)is adopted to simulate the interaction between level ice and ship hull.The level ice is modeled with 3D bonded spherical elements considering the buoyancy and drag force of the water.The parallel bonding approach and the de-bonding criterion are adopted to model the freezing and breakage of level ice.The ship hull is constructed with rigid triangle elements.To improve computational efficiency,the GPU-based parallel computational algorithm was developed for the DEM simulations.During the interaction between the ship hull and level ice,the ice cover is broken into small blocks when the interparticle stress approaches the bonding strength.The global ice resistance on the hull is calculated through the contacts between ice elements and hull elements during the navigation process.The influences of the ice thickness and navigation speed on the dynamic ice force are analyzed considering the breakage mechanism of ice cover.The Lindqvist and Riska formulas for the determination of ice resistance on ship hull are employed to validate the DEM simulation.The comparison of results of DEM,Lindqvist,and Riska formula show that the DEM result is between those the Lindqvist formula and Riska formula.Therefore the proposed DEM is an effective approach to determine the ice resistance on the ship hull.This work can be aided in the hull structure design and the navigation operation in ice-covered fields.  相似文献   

8.
很高兴前来参加“国际极地年中国行动”启动仪式。国际极地年是全球范围的科学家共同策划、联合开展的大规模极地科学考察  相似文献   

9.
以长海县1993年和2005年Landsat-TM数据为基础,运用遥感软件ENVI,经噪音剔除、主成分变换、彩色合成、分类处理、差值运算提取出长山列岛新增建设用地,生成新增建设用地矢量数据,结合GIS软件MapInfo,经过投影转换、叠加分析、缓冲区分析、空间信息统计,分析新增建设用地的空间分布及影响机制,结果表明:长海县的建设用地在1993-2005年不同程度地增加,人口及经济发展是建设用地增加的主要促进因子;交通干线对新增加的建设用地具有空间吸引效应;新增建设用地有向港口等基础设施集中的特征;新增建设用地空间分布受到已有产业功能分区的影响.研究表明,RS&GIS支持下,利用TM数据分析海岛建设用地变化具有一定的应用前景.  相似文献   

10.
Knowledge about organic carbon loadings(ratio of sedimentary organic carbon(SOC)content to specific surface area(SSA))and the fate of organic carbon(OC)is critical to understand the marine carbon cycle.We investigated the variations in the patterns of OC loadings and the preservation capacities of sedimentary OC in the Yap Trench and other marine environments.The average OC loading in sediment cores from various marine environments decreases with increasing water depth at a rate of^0.06 mg OC/(m^2·km)(R^2=0.23,P<0.01).Distinct low OC loadings(0.09±0.04 mg OC/m^2)were observed in the Yap Trench,with the lowest values as^0.02 mg OC/m^2.A further comparative analysis indicated that OC/SSA=0.2 mg OC/m^2 is a good indicator to distinguish between oxic deep-sea regions and suboxic energetic deltaic areas.Regression analysis between OC loading and bulk carbon isotope compositions indicates that marine OC(δ13C^-20.4‰to-18.6‰)dominates the lost OC within the Yap Trench and does not differ from that of the abyssal zone.In contrast,terrestrial OC withδ13C values of approximately-27.4‰to-20.5‰was the major source of remineralized OC in the sublittoral zone.The ratios of OC loadings in the bottom layer relative to those in the top layers of sediment cores indicate that the preservation capacities of hadal trenches are much lower than those of other environments,and only approximately 30%of the SOC deposited in hadal trenches is finally buried.The value is equivalent to 0.066%of the primary production-derived OC and much lower than the global ocean average(~0.3%).Overall,the hadal zone exhibits the lowest OC loading and preservation capacity of SOC of the different marine environments investigated,despite the occurrence of a notable funneling effect.  相似文献   

11.
厦门香山至长尾礁沙滩修复实践及理论探讨   总被引:2,自引:0,他引:2  
以厦门香山~长尾礁沙滩修复工程为例,研究了海滩的修复和改造技术.香山~长尾礁沙滩位于厦门东海岸,岸段原始沙滩已消失殆尽,于2007年10月完成海滩修复的一期工程,海滩的宽度和质量经一年来的监测,改造基本稳定,并明显好于历史时期的海滩.从选址条件、海滩设计要素及施工方法等方面,探讨了人造海滩修复的主要内容及修复后海滩的成长过程.  相似文献   

12.
厦门岛东北部海滩回填重塑研究   总被引:6,自引:1,他引:6  
陈坚  蔡锋  许江  张海峰 《台湾海峡》2002,21(2):243-251
在对厦门岛东北部海滩改造条件评价的基础上,选定泥金南部,长尾礁一下保-香山段海滩作为海滩回填重塑靶区,着重对下保-香山段海滩改造在海滩平衡,上下限高程,回填宽度,坡度,回填量及辅助工程措施等方面进行了研究,并提出相应的回填改造参数。  相似文献   

13.
人工海滩研究进展   总被引:11,自引:0,他引:11  
海滩是激浪作用下泥沙在激浪带的堆积,是海岸带最活跃的地貌单元。近年来,由于世纪性的海平面上升,侵蚀型海滩范围扩大,侵蚀加重,海滩宽度变窄、坡度变陡和滩面物质粗化等问题日益严重,引起了广泛关注,亦成为海岸工程研究的热点课题之一。几十年的工程实践表明,海滩喂养与人工海滩是当前防护海滩侵蚀最有效的措施,并已为欧、美、日等国广泛应用。利用海岸地貌学原理方法,借鉴模拟环境条件类似的周边自然海滩的形成和演变规律,合理的设计海滩物质的颗粒大小和组成,海滩的坡度、高度、宽度以及填砂范围等关键参数,能够有效地使人工海滩更快的达到平衡状态并维持其稳定。在海滩的娱乐休闲功能在国际范围内日益受到重视的今天,这一方法在海岸工程应用上具有重要的现实意义。  相似文献   

14.
近岸人工沙坝保滩促淤的试验研究   总被引:1,自引:0,他引:1  
吴建  拾兵  李智  刘德飞  范菲菲 《海洋通报》2012,31(2):176-180
借助正态波浪模型,对北戴河海滩某横断面有、无沙坝布置进行了3种水位的极限波高入射试验,测取了坝内外波高过程线及稳定后的断面地形。试验资料及理论分析显示:有无沙坝时沿岸流及波浪的挟沙能力之比与水下沙坝的波浪透射系数的平方成正比,按试验最大透射系数计算的挟沙能力亦可降50%左右,且有沙坝上涌带破波回流对岸滩的冲刷水深可以维持在平均海平面以下1 m内,说明人工沙坝的填筑很大程度促使水体挟带泥沙于掩护区域落淤有效的阻止了泥沙的离岸亏损。试验将为保滩促淤工程设计与实施提供科学依据。  相似文献   

15.
Morphodynamic classification of beaches has achieved widespread acceptance in both geological and geomorphological literature. In this sense, the present work classifies twelve Mediterranean low energetic beaches according to the dimensionless fall parameter (Ω) parameter in the Island of Mallorca. Propagation of 44 yr of wave data as well as a detailed sediment study allows to provide probabilities for morphodynamical beach state on an annual and seasonal basis. Consequently, beaches in Mallorca fall between three major categories which are (a) truly reflective, (b) reflective skewed to intermediate and (c) intermediate beaches. The Mallorcan beach position in the morphodynamical scheme is close related to the physiographical and geological framework. Comparison of observed values with those obtained in the analysis leads that for gross beach classification there is agreement between predicted and real state. However on a seasonal classification, mainly during summer, there is no agreement between the predicted state and the real one. As the model does not incorporate the role of summer sea breezes, beach reflective states are highlighted. Real beach configurations correspond to more energetic wave dynamic conditions and to intermediate state scenarios.  相似文献   

16.
渔港硬式构筑物如防波堤等对海岸的影响显著。以福建泉州崇武半月湾渔港防波堤修建前后的海滩变化为例,通过对20032011年不同阶段海滩地貌形态、岸线变化分析以及2个海滩剖面多期监测比较发现,防波堤修建后海湾下游西侧海滩发生显著蚀退,西端侵蚀强度最大,向东(靠近防波堤遮蔽段)逐渐减小,中东部遮蔽段转为淤涨。海滩变化的主要原因:1)E2011年不同阶段海滩地貌形态、岸线变化分析以及2个海滩剖面多期监测比较发现,防波堤修建后海湾下游西侧海滩发生显著蚀退,西端侵蚀强度最大,向东(靠近防波堤遮蔽段)逐渐减小,中东部遮蔽段转为淤涨。海滩变化的主要原因:1)ESE向主入射波浪受到防波堤的阻挡作用,在堤头发生绕射,港内波影区动力变弱;2)防波堤阻碍了从东向西的沿岸流运动,形成东向为主的沿岸输沙,使得东端发生堆积,造成下游的西侧海岸的沉积物亏损,发生侵蚀。针对海岸变化机理提出了海滩养护防御措施,并通过数值模拟预测说明养护海滩以由西向东输沙为主,年均输沙量约3万m3,堆积于遮蔽段,最后,提出采用周期性抽取遮蔽段养护沙补充到西端的方法来实现海滩循环养护。  相似文献   

17.
岬间海滩泥沙输运趋势与剖面分形研究   总被引:1,自引:0,他引:1  
根据1999年7月实测的粤东岬间海滩沉积与地形变化资料,采用沉积物输运概率模式(McLaren模型)对海滩沿岸泥沙运移趋势进行探讨。结果表明,在常波况条件下海滩沿岸泥沙向偏南方向运移,在高能条件下可能出现与常波况条件下相反运动的趋势。进一步利用分形分布模型研究了海滩剖面的分形性质,提出了岬间海滩剖面地形变化的短期分形预测模型。  相似文献   

18.
By use of a shoreline-change numerical model (GENESIS) based on one-line theory, a preliminary modeling study on shoreline changes caused by a beach nourishment project in Beidaihe, China, is presented in this paper. Firstly, the GENESIS model is verified and model sensitivity to the major parameter changes is discussed by simulating a hydraulic model test. The beach nourishment project, after that the shoreline change is kept being monitored, is a small-scale emergency one carried out to use two bathing places on the west beach in the summer, 2008. In this paper the shoreline changes caused by the beach nourishment project are modeled by the GENESIS model, and the computed results fit well with the measured shorelines. With the same model and parameters, a long-term performance of the project is predicted, and the result shows that the bathing places only can be suitable for bathing in 2 to 3 years without subsequence nourishment project. Therefore, it is proposed to nourish the beaches in time to keep the service life of the beach in recent years and carry out the beach nourishment project for the whole west beach as soon as possible.  相似文献   

19.
厦门海滨浴场的环境质量及容量研究   总被引:5,自引:0,他引:5  
欧寿铭  杨顺良 《台湾海峡》2001,20(4):471-477
本文依据现场调查及测验结果,综合分析、评估厦门市海滨浴场的资源与质量的现状及存在问题,并依据现有沙滩资源估算海滨浴场的客容量。结合厦门作为国际港口风景旅游城市的发展趋势,提出采用人工造滩的方法来增添新的海滨浴场,不仅可以改善海滨浴场的布局,同时还可以增加客容量。  相似文献   

20.
海滩剖面设计参数确定和稳定性评价是设计阶段确保海滩养护工程质量的重要指标。针对大连凌水湾砾石海滩养护工程,综合采用Dean平衡剖面原则和剖面类比法进行剖面设计,确定了填砂中值粒径、施工坡度、滩肩前沿高程和滩肩宽度等设计参数;结合物理模型试验进行了剖面形态稳定性分析,研究了海滩在不同波浪和水位作用下的剖面形态演化过程,试验结果表明不同工况条件下,平均低水位以上的滩面均为净淤积,水下部分侵蚀明显,滩面上部泥沙不断堆积,砾石海滩最终形成稳定剖面。研究结果可为类似砾石海滩养护工程设计提供参考。  相似文献   

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