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31.
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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
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Nowadays there are some chronic serious environmental problems, such as eutrophication, blue tide and so on, in a complicated coastal zone or a semi-enclosed bay, because the water exchanges between an inner bay and an outer sea is weak compared with the supply of contaminant. Under this situation, a method to improve the water quality by 3-dimensional small unsymmetrical structures has been proposed by Komatsu et al. In this paper, several numerical simulations of the tidal current and concentration for various arrangements of bottom roughness in a semi-enclosed model bay are carfled out with a depth-averaged 2-D numerical model. The model is solved by the hybrid finite analytic method with nonstaggered grid. And the SIMPLES algorithm with Rhie and Chow' s momentum interpolation technique is used for the simulation. The effect of Komatsu' s method for water purification is examined by numerical simulation. The result of numerical experiment indicates that it is possible to generate a new tidal residual current and to activate a tidal exchange by bottom roughness arrangement only. 相似文献
35.
This article describes the impact of satellite altimeter data on the simulations of sea level variability (SLV) by a nonlinear reduced gravity model of the entire Indian Ocean. The model has been forced by 6-hourly analyzed wind stress data containing SSM/I observations and has been able to produce realistic circulation features. However, SLV values observed by Topex/Poseidon altimeter do not fit these simulations because of imperfect initial data. Hence an attempt has been made to initialize the model using altimeter data. The initialized model-generated SLVvalues have been compared with SLV derived by altimeter for monsoon as well as nonmonsoon months of 1996. Experimental runs have been performed for 10 days, 20 days, and one month. It has been found that the initialized model results on the final day of these experiments are in very good agreement with altimeter data of the same day. It is thus possible, in principle, to hindcast and forecast sea level variations in the time scale of 10 days to one month with the availability of good quality wind data for forcing the model and altimeter observations of sea level for initializing it. 相似文献
36.
Modelling nitrogen and phosphorus cycles and dissolved oxygen in the Zhujiang Estuary Ⅰ. Model development 总被引:1,自引:0,他引:1
wrmcrloxHuman activities related to the population growth and developrnent of industry and rnwhci-pality have led to the incrouing hadings of various POllutants into estudries during the past fewdecades. These increasing edlutant lOadings have caused declined estuallne hedth which can bemereured by a vdriety of indices. In order to obtain solutions to environrnent problerns, re-sources manageTnnt apencies are supporting a holistic approach to envirorirnental management.An effcient strategy t… 相似文献
37.
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
38.
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
39.
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
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
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