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151.
152.
乌苏里地区构造新探索 总被引:15,自引:0,他引:15
通过乌苏里地区中苏合作对比研究,对该区的构造有了以下一些新的认识:若干地体的拼贴奠定了东北亚大陆边缘的构造格局,地体的拼贴在时空上是有规律可寻的,这一规律解释了地槽学说对该区构造解释中的疑难问题。通过那丹哈达-比金地体外来岩块的地层对比,建立了一套完整的层序,在利恢复地体漂泊的历史。通过对比还发现苏联远东溪海地区和中国延吉地区可能同是不凯地体二叠纪的活动大陆边缘,三叠纪也经历了共同的演化历史。 相似文献
153.
中国大气环境光学探测研究 总被引:1,自引:0,他引:1
激光/波谱技术促进了大气立体监测技术的发展,以光学探测和光谱数据解析为核心、以紫外、可见到红外全光谱为探测波段的各种高分辨率光学监技术,在中国逐渐实现了从近地面到100 km大气气象要素和大气痕量成分实时探测的能力,以及近地面到50 km大气多要素的实验模拟能力。光学技术以高灵敏度、高分辨率、高选择性、多组分以及实时等优势,在大气环境领域日益发挥作用,为研究大气污染演变与气象过程相互作用、大气细粒子污染和光化学烟雾形成机理等基础科学问题研究提供数据支持,为揭示城市和区域尺度的大气复合污染特征、量化其环境影响,提供科技支撑。 相似文献
154.
At present, most researches on the vortex-induced vibration of submarine free spanning pipelines ignore the effect of internal flowing fluid; furthermore, there are no research reports considering the coupling effect of internal and external fluid with the free span. In this paper, combining Iwan‘s wake oscillator model with the differential equation derived for the dynamic response of submarine free spanning pipelines with inclusion of internal flow, the pipe-fluid coupling equations are developed to investigate the effect of internal flow on the vortex-induced vibration of the free spans. The finite dement approximation is implemented to derive the matrix equations of equilibrium. The Newmark method combined with simple iteration is used to solve the system of equations. The results indicate that the internal fluid flow may cause the shift of resonance band to the lower frequency and a slight decrease in the peak value; the effect will be mare pronounced with the increase of the span length and can be weakened in the presence of the axial tension. 相似文献
155.
Two- and three-dimensional finite element analysis programs for pile-soil interaction are compiled. Duncan-Chang's Model is used. The construction sequence of the pier is modeled. The pile-soil interface element is used. The influence of the combination type of piles on the deformation of bank slope and pile behaviour is analyzed. Different designs of a pile-supported pier are compared thoroughly. Calculation results show that the stresses and displacements of the pile are directly related to the distance from the bank slope and the direction of inclination. An inclined prop pile set in the rear platform would remarkably reduce the stresses of piles and the displacement of the pier. 相似文献
156.
Zuo Qihua Yao Guoquan
Ding Bingcan Senior Engineer Nanjing Hydraulic Research Institute Nanjing Engineer Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1993,(1)
- This paper considers the effects of wave energy dissipation induced by sea-bottom friction on the computational results of water wave refraction and diffraction with the parabolic equation method. The presented results show that the friction factor formula adopted in this paper is of higher numerical accuracy than that introduced by Dalrymphe (1984), and it can be used to compute wave propagation over large open areas. 相似文献
157.
Method to Determine Depositional Range of Sediment Transported from Multiple Sources in Water Area 总被引:1,自引:0,他引:1
Ying Qiang Jing Fei Ma Jin Rong
Engineer Nanjing Hydraulic Research Institute Nanjing Lecturer Nanjing College of Navigation Engineering Nanjing Assistant Engineer Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1995,(3)
- The sediment from different sources have different content of the characteristic elements. According to the fuzzy mathematical theory, corresponding calculation and cluster analysis of each sediment sample are carried out, so the main courses of sediment transport in water area can be obtained. The characteristics of sediment from different sources are analysed. It is found that the sediment deposited of certain point in water area is due to the sources' contributions which can be calculated by the formula derived in this paper. Based on the distribution of the contribution values, the depositional range of sediment from each source can be determined. The depositional range in Huangmao Bay is determined as an example. 相似文献
158.
Local scour around a bridge pier is an important pm‘mneter for the design of a bridge. Compared with the local scour in a mono-directional current, the local scour in a tidal current has its unique characteristics. In this paper, several aspects of local scour around bridge piers in tidal current, including the scour development process, the plane form of a scour hole and the maximum scour depth, are studied through movable bed flume experiments. 相似文献
159.
Gu Jie Kuang Cuiping
Engineer Nanjing Environmental Protection Research Institute Nanjing .
Senior Engineer Doctor Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1996,(3)
- A combined numerical model for computing mixing areas of pollution vertical jet discharging into tidal flows has been developed. This numerical model is composed of a 2-D depth-averaged dynamic far-field numerical model and a 2-D vertical dynamic near-field numerical model. The former uses finite node method to compute velocity, and improved finite node method to compute pollutant concentration distribution; the latter is a k-e turbulence model, and uses SIMPLE (Semi-Implicit Method for Pressure Linked Equations) method to compute velocity. At the same time, the former provides boundary conditions for the latter. This model can simulate both far- field pollutant concentration distribution and near-field vertical recirculation quickly and precisely. This model has been verified by measured data of pollutant F of the Dachang reach of the Changjing River and test data presented by Chen el al. (1992). On the basis of verification, the authors use a designed hydrograph to compute this mixing area for a cer 相似文献
160.
Tao Tongkang Yu Long Yan Jun Dong Zhiyong
Prof. Senior Engineer Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing
Graduate Student Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing Engineer Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing Associate Professor Hydraulic Engineering Department Nanjing Hydraulic Research Institute Nanjing 《中国海洋工程》1997,(2)
This paper investigates the performance of geomembrane composites used as impervious andheat-insulating lining within a breakwater for a power station.The seepage field,distribution ofstress-strain contour and seepage discharge of hot water which has been treated as the inner thermalsource in the calculation of heat-insulation,have been given by three-dimensional calculation method coup-ling seepage with stress.The results indicate that the impervious and heat-insulation effect ofgeomembrane composites is significant. 相似文献