溴素的有机化学──Ⅴ.溴代脂肪酸—2,3,5,6—四溴—1,4—苯二酯的合成     

崔伟  孙明昆  钱佐国  刘升一 《中国海洋大学学报(自然科学版)》1996,(3)

以1，4—苯二酚和不同的短链脂肪酸为基本原料，经溴代、加成、形成酰卤和酰化等反应，合成了六种新的溴化脂肪酸—2，3，5，6—四溴—1，4—苯二酯。通过对产物的碳、氢、溴等元素的定量分析，以及红外吸收光谱和氢核磁共振谱的研究，验证了化合物的结构。  相似文献   

Observation of clouds and solar radiation over the Pacific Ocean as relation to global climate     

Farn Parungo  Clarence Nagamoto  Cecilia M. I. R. Girz  Jeff Torgerson  Zhou Mingyu 《海洋学报(英文版)》1995,14(2):201-207

ＯｂｓｅｒｖａｔｉｏｎｏｆｃｌｏｕｄｓａｎｄｓｏｌａｒｒａｄｉａｔｉｏｎｏｖｅｒｔｈｅＰａｃｉｆｉｃＯｃｅａｎａｓｒｅｌａｔｉｏｎｔｏｇｌｏｂａｌｃｌｉｍａｔｅ￥ＦａｒｎＰａｒｕｎｇｏ；ＣｌａｒｅｎｃｅＮａｇａｍｏｔｏ；ＣｅｃｉｌｉａＭ．Ｉ．Ｒ．Ｇｉ...  相似文献   

Fractal Determination of Coastal Types Based on GIS--A Case Study of China     

Zhu xiaohua  WU Xiuqin  Wang Jian 《海洋通报(英文版)》2002,4(2)

The probability of fractal determination of coastal types based on GIS is preliminarily discussed with China as an example. Finally, some significant conclusions are drawn: (1) The fractal dimension of coastline of the bedrock coast is larger than that of the plain coast on the same scale map; (2) As far as the bedrock coast is concerned, the larger fractal dimension of coastline of the bedrock coast on the same scale map indicates that the bedrock coast is probably not typical; (3) As far as the plain coast is concerned, the smaller fractal dimension of coastline of the plain coast on the same scale map indicates that it is probably the silt plain coast; (4) The different substantial compositions affect the fractal dimensions of coastlines of different coastal types. In general, the coast which lies in the north of the Hangzhou Bay consists of sand mainly, its surface is flat, and it is connected with the coastal plain, its landform is broad shoal, its total change is comparatively homogenous in the tidal dynamic process, and thus, the relatively smaller fractal dimension of coastline results from this. For the bedrock coast, there is more bedrock, the coastline is comparatively smooth and straight, being affected by the faults and ocean dynamic process, which result in the larger fractal dimension.  相似文献   

正压浅海湍流运动的雷诺应力封闭模型     

徐肇廷  楼菁  鹿有余 《中国海洋大学学报(自然科学版)》1991,(3)

根据湍流封闭理论,建立一种适用于正压浅海湍流运动的雷诺应力封闭模型(RSM),以代替目前三维浅海动力学模型中普遍采用的湍粘性系数的传统假设。通过直接建立并模化f—平面上正压海洋的雷诺应力传输方程,分别得到的微分形式和代数形式的RSM方程组。并讨论了进行数值计算所需要的边界条件。利用该模型可以进一步研究浅海潮流、风暴潮流及风海流等浅海流动的三维结构和湍流特性。  相似文献   

太平洋西部3个岩芯沉积物的粒度组成及其天然湿容重和含水量的变化     

徐善民  周秀廷  高申禄  阎军 《海洋科学》1992,16(1):64-68

本文讨论了太平洋西部3个岩芯孔的粒度组成、天然湿容重和含水量的变化。沉积物组成以粉砂和粘土细粒为主,砂粒含量很少,而且多为有孔虫介壳。容重与沉积物粒度呈正相关,含水量则呈负相关。当粒度组成不变时,容重随岩芯埋藏深度的增加而增大,而含水量则减少。  相似文献   

Numerical Study on Instantaneous Discharge of Unsorted Particle Cloud in Cross Flow     

顾杰  李志伟杨红 詹咏 《中国海洋工程》2007,21(2):305-316

The mixing characteristics of particles such as dredged sediment of variable size discharged into cross flow are studied by a 3D numerical model, which is developed to model the particle-fluid two-phase flow. The Eulerian method with the modified k-ε parameterization of turbulence for the fluid phase is used to solve fluid phase, while a Lagrangian method for the solid phase (particles), both the processes are coupled through the momentum sources. In the model the wake turbulence induced by particles has been included as additional source term in the k-ε model; and the variable drift velocities of the particles are treated efficiently by the Lagrangian method in which the particles are tracked explicitly and the diffusion process is approximated by a random walk model. The hydrodynamic behavior of dumping a cloud of particles is governed by the total buoyancy of the cloud, the drag force on each particle and the velocity of cross-flow. The computed results show a roughly linear relationship between the displacement of the frontal position and the longitudinal width of the particle cloud. The particle size in the cloud and the velocity of cross flow dominate the flow behavior. The computed results are compared with the results of laboratory experiments and satisfactory agreement is obtained.  相似文献   

Design of ship's bow form by potential-based panel method     

Jaehoon Yoo   《Ocean Engineering》2007,34(8-9):1089-1095

A surface panel method treating a boundary-value problem of the Dirichlet type with the free surface is presented to design a three-dimensional body corresponding to a prescribed pressure distribution. The free surface boundary condition is linearized with respect to the oncoming flow, and computed by four-point finite difference scheme. Sample designs for submerged spheroids and Wigley hull are carried out to demonstrate the stable convergence, the effectiveness and the robustness of the method. The design of a 5500TEU container carrier is performed with respect to reduction of the wave resistance. To reduce the wave resistance, calculated pressure on the hull surface is modified to have the lower fluctuation, and is applied as a Dirichlet type dynamic boundary condition on the hull surface. The designed hull form is verified to have the lower wave resistance than the initial one not only by computation but also by experiment.  相似文献   

东海水系与生物关系的初步分析     

苗育田  于洪华 《海洋与湖沼》1992,23(2):175-181

本文利用中日黑潮联合调查研究期间1986年5—6月和1989年7—8月航次水文与生物的同步取样资料,分析了东海测区内水系组成与浮游甲藻类及浮游桡足类等分布之间的对应关系。指出了不同生态类型的生物需要不同的物理海洋环境条件。同时,某些指示生物的分布又为区分水系、了解流系情况提供了良好的示性指标,并且从某些生物数量的变化还可以判断出水系混合与变性的程度。  相似文献   

东营城区高精度三维地震采集方法研究   总被引：3，自引：0，他引：3  

胡立新  刘怀山  张进 《中国海洋大学学报(自然科学版)》2004,34(6):1075-1080

根据东营城区内建筑物较多，环境干扰较大，地下构造复杂，断裂非常发育，目的层埋藏深，资料信噪比较低的特点，以地震老资料和钻井资料为基础，建立地震地质模型，利用射线追踪技术选取合适的观测系统参数。充分利用卫星数字地图，没计了灵活多变的观测系统，采用可控震源与炸药震源配合使用方法，及时对城区内地下面元的覆盖次数、方位角和炮检距的分布进行质量监控，利用现场处理系统对资料进行及时分析，提高了地震资料品质。所获得的东营城区高精度三维地震采集资料显示，其浅中层分辨率和中深层信噪比都有了明显改善，取得了良好的地质效果。  相似文献   

桶形基础平台三维有限元稳定性分析     

钱荣  周锡礽  孙克俐  张伟 《海洋技术学报》2003,22(4):49-53

以我国第一座桶形基础采油平台工程实例为原型，采用三维有限元计算方法对桶形基础稳定性分析。平台在波浪、风等荷载作用下，其稳定性不仅与平台的整体结构有关，而且与桶形基础及其周围土体相互作用相关。在计算中，利用薄层摩擦单元模拟土与结构间的相互作用，取得了很好的效果。分析结果表明桶形基础采油平台在设计条件下运行是较为稳定的。  相似文献