Model Test Study of Dynamic Ice Force on Compliant Conical Structures     

黄焱  史庆增宋安 《中国海洋工程》2007,21(1):11-22

To study ice-induced vibration of a compliant conical structure,a series of model tests were performed from 2004 to 2005.In the tests,the ice sheet before the compliant conical structure was found to fail in two-time breaking.From 2005 to 2006,this type of ice failure was studied through more groups of tests.The tests show that two-time breaking is the typical failure of ice before steep conical structures,and is controlled by other factors at the same time,such as ice speed and the angle of the cone.  相似文献   

Spatial and temporal variations of mesozooplankton in the Pearl River estuary, China   总被引：10，自引：0，他引：10  

K.Z. Li  J.Q. Yin  L.M. Huang  Y.H. Tan   《Estuarine, Coastal and Shelf Science》2006,67(4):543-552

This paper examines spatial and temporal variations of mesozooplankton abundance, biomass and community structure during three cruises of July 2002 (summer), January 2003 (winter), and April 2003 (spring) in the Pearl River estuary, China. Zooplankton abundance and biomass fluctuated widely and showed distinct heterogeneity in the Pearl River estuary. A total of 154 species were identified during three surveys. The number of zooplankton species richness was strongly linked to salinity. Hierarchical cluster analysis identified three zooplankton groups during this study. Estuarine, neritic and pelagic groups corresponded to the upper, middle and lower reaches in the Pearl River estuary. The difference among groups could be mainly ascribed to changes in the relative contributions of the dominant species. The fluctuations in the zooplankton abundance, biomass and community structure were determined by the interactive effects of freshwater inflow, tidal and coastal currents, chlorophyll a, salinity and temperature. Significant spatial variability in the distribution of zooplankton species, abundance and biomass can be ascribed to the virtual presence of a horizontal gradient in salinity.  相似文献   

松辽盆地西部张裂缝预测的应力场方法     

朱庆杰  朱而勤  尹万泉  吴战国 《中国海洋大学学报(自然科学版)》1995,(3)

以松辽盆地地质资料为基础，介绍了应力场和张裂缝预测的计算方法。通过了各种岩性的张破裂概率隶属函数，预测松辽盆地酉部张裂缝区的分布。据此，为今后的油气勘探提出了几点认识和建议。  相似文献   

Comparison of Strain-rate Dependent Stress-Strain Behavior from Ko-consolidated Compression and Extension Tests on Natural Hong Kong Marine Deposits     

Jian-Hua Yin  Chun-Man Cheng 《Marine Georesources & Geotechnology》2006,24(2):119-147

This article presents results from a series of K_o-consolidated compression and extension triaxial tests on specimens from undisturbed samples of Hong Kong Marine Deposits (HKMD). To investigate the strain-rate effects, a total of seven K_o-consolidated triaxial tests were conducted including four compression tests and three extension tests. After K_o-consolidation, the triaxial test specimens were sheared at step-changed axial strain rates under three different confining pressures of 50 kPa, 150 kPa, and 400 kPa, respectively. The step-changed strain rates were applied in the following order: +2%/h, +0.2%/h, +20%/h, -2%/h (unloading) and +2%/h (reloading) for the four compression tests and -2%/h, -0.2%/h, -20%/h, +2%/h (unloading) and -2%/h (reloading) for the three extension tests. The results are reported and analyzed in the paper. The results show that the strain rate effects, the stress-strain characteristics, and the effective stress paths of the specimens for tests in a compression state are different from those for tests in an extension stage. One order of magnitude increase in axial strain rate causes an average 8.6% increase in undrained shear strength for compression tests and a 12.1% increase for extension tests. It is also found that the failure mode of the specimens in compression is different from that in extension. The stress-strain behavior of specimens shows strain-softening and a clear shear band in compression tests, but strain-hardening without any clear shear band in extension tests for the same absolute value of axial strain.  相似文献   

Observational evidence of the upwelling off cape shioyazaki in Fukushima Prefecture,Japan     

Hui Soo An 《Journal of Oceanography》1980,36(1):85-95

Using serial observations, evidence of the existence of upwelling in the region between the northeast flowing Kuroshio and the coast of Ibaraki and Fukushima Prefectures is presented. The complex and variable oceanic condition in this region sometimes conceals some of the evidence of upwelling. Evidence of upwelling can be seen in the distributions of temperature and salinity, and more clearly in those of dissolved oxygen and phosphate. The average position of the upwelling region is just off Cape Shioyazaki in Fukushima Prefecture. Such an upwelling phenomenon may be a general oceanic feature characteristic of the region at the poleward edge of western boundary currents.  相似文献   

Combined refraction and diffraction models for sea waves over complicated topography and with currents in shallow water     

Yin Baoshu  Jiang Decai 《海洋学报(英文版)》1990,9(1):13-23

-Combined refraction and diffraction models in the form of linear parabolic approximation are derived through smallparameter method. More strictly theoretical basis and more accuracy in the models than Lozano's (1980) are obtained. Some theoretical defects in Liu's model (1985) with consideration of current are not only found but also eliminated. More strict and accurate models are, therefore, presented in this paper.The calculation results and analysis in applying the models to actual wave field with consideration of bottom friction will be given in the following paper.  相似文献   

海洋发光弧菌生长和发光条件的研究     

方宏达  董燕红  袁茵  李秀芹  易斌 《海洋通报》2007,26(4):66-70

海洋生物发光研究对渔业、环境监测等有着举足轻重的意义。根据从湛江东海岛海域沉积物样品中分离出的一株海洋发光弧菌(Vibrio sp.,编号为D2),对这株菌的生长和发光条件进行了初步研究。实验结果表明,海洋发光弧菌D2在pH7.0、温度35℃、NaCl浓度为2.0%时,生长状态最好;在pH5~6、温度20℃、NaCl浓度为3.0%、细菌密度OD600达0.08时,发光强度最高。  相似文献   

利用X射线衍射测定单斜辉石中硬玉组分含量     

王文正  韩宗珠  安英杰 《海洋湖沼通报》1993,(4):45-48

硬玉是单斜辉石中十分重要的端元组分,是单斜辉石分类的主要基础。利用x射线衍射分析确定的硬玉组分含量计算式为Jd(％)=[A-2.235]×25.741,其中Jd为硬玉组分百分含量,A为2—Theta角为30°(d=2.97)时峰值的相对强度Ⅰ与半高宽的乘积,其计算误差仅6.32％。  相似文献   

Annual and interannual variations of large-scale circulation over the tropics as revealed from OLR data   总被引：1，自引：0，他引：1  

Xie An  Chen Longxun  Takio Murakami 《海洋学报(英文版)》1988,7(2):195-202

In this study, the outgoing longwave radiation (OLR) data of eight years have been used to investigate the annual and interannual variations of large-scale circulation over the tropics. The results of EOF analysis indicate that the first three eigenvectors reflect the essential features in OLR annual variation. However, they contribute little to the interannual change. In comparison, the fourth to the sixth components have very large year-to-year variations. The pronounced anomalies are located over the tropics with east-west dipole pattern. It implies that ENSO events are related closely to the variation of the Walker circulation.  相似文献   

我国海水制盐工艺改革的设计研究     

周仲怀  徐丽君  于银亭  王建华  于廷芳  王继业  殷丽 《海洋科学》1997,21(6):43-46

从技术上和工艺上的可能性、可行性和合理性，论证了海水制盐工艺改革的必要性，并且提出了实现海水制盐工艺改革的各种设计方案。它对我国的海水制盐工业的发展将具有深远意义。  相似文献