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101.
YAN Mingyan LI Bafang ZHAO Xue College of Food Science Engineering Ocean University of China Qingdao P. R. China 《中国海洋大学学报(英文版)》2009,(2)
Collagen of squid(Ommastrephes bartrami) skin was examined in the present study. Histology showed that collagen fiber in the skin was partially cross-linked with muscle fiber. Acid-solubilized collagen(ASC) and pepsin-solubilized collagen(PSC) were extracted from the skin and characterized. The results of amino acid composition and electrophoretic patterns revealed that ASC and PSC were both type Ⅰ collagen,containing α1 and α2 chains. FTIR(fourier transform infrared spectroscopy) investigations confirmed t... 相似文献
102.
The Yangtze Estuary, the largest estuary in China, is under an obvious interaction between runoff and astronomical tide. The research on the interaction is very important for the exploitation and utilization of water resources in this area. A horizontal 2D hydrodynamic numerical model is established and verified in the present study with the modeling range from Datong to the Yangtze Estuary. Based on the comparison of high water levels under the interaction between different runoff and estuarine dynamics, s... 相似文献
103.
Method of checking for jack-up elevated performance including leg structure strength, fixation system or jacking system bearing capacity, pre-load requirements, spud can bearing capacity and overturning stability is suggested in this paper. As an example, a jack-up with truss legs is analyzed by finite element analysis method. This paper may be helpful to the rig owners, operators and designers. 相似文献
104.
Corrosion and fatigue cracks are major threats to the structural integrity of aging offshore platforms. For the rational estimation of the safety levels of aging platforms, a global reliability assessment approach for aging offshore platforms with corrosion and fatigue cracks is presented in this paper. The base shear capacity is taken as the global ultimate strength of the offshore platforms. It is modeled as a random process that decreases with time in the presence of corrosion and fatigue crack propagati... 相似文献
105.
It is necessary to pay more attention to the durability of concrete undergoing freeze-thaw cycles and seawater attack simultaneously.Investigated are the effects of water-binder ratio,fly ash (FA) contents and air-entraining agent on resistance to frost and chloride diffusion of marine concrete blended with FA in natural seawater.The results show that fly ash does not improve the frost resistance of concrete but can improve its resistance to chloride diffusion by addition of less than 30%.The resistance to frost and chloride diffusion of FA concrete can be improved with the decrease of water-binder ratio,and FA may improve both of them simultaneously only being mixed with air-entraining agent.A ratio (named as R) of the frost-resisting durability factor to chloride diffusion coefficient can be used to evaluate the durability of marine concrete.Scanning electron microscope (SEM) analyses are consistent with the evaluations by the value of R. 相似文献
106.
GPS���ܵ��㶨λ��Ӱ������ʱ������ؼ���ʩ���� 总被引:1,自引:0,他引:1
??GPS??????λ?????????У?????????????????估???????λ??????????????????????????????????????????λ????????????λ?????????????????????????????????????????????????????????伸?ι?????????????????????????????Щ??????????????????????????????????????????????????????? 相似文献
107.
异常流量在目的地址与出现时间上的分布均与正常流量有很大区别。文中对校园网的出口流量进行分析实验,将其NetFlow记录按校外IP地址的前16位聚类,得到的部分网段在出入流量中的出现频度有明显特点。分析2种典型网段,研究由此发现校园网内的异常流量源的方法,并对2种异常流量源的区别进行了分析。此方法与常用的异常检测方法相比,所需处理的数据量大为减少,大大提高了检测效率。 相似文献
108.
珠江口滨海湿地退化现状、原因及保护对策 总被引:1,自引:0,他引:1
2007年和2008年秋季对珠江口滨海湿地进行了环境现状综合调查,结果表明,珠江口滨海湿地退化主要表现在4个方面:天然湿地面积减少、湿地生产力不断下降、湿地环境状况持续恶化和湿地景观破碎化。珠江口滨海湿地退化的原因主要为滩涂开发与围填海、污染物排放、养殖污染、海平面上升、过度捕捞、海砂开采和港口码头建设以及水土资源开发等因素。滨海湿地保护与利用对策主要有:制定有关滨海湿地保护的法律法规和湿地保护与利用规划;加强人才队伍建设和滨海湿地有关技术研究;建立滨海湿地动态监测体系;加大滨海湿地保护区建设的力度;加强宣传和教育。 相似文献
109.
Single Zircon LA-ICP-MS U-Pb Dating of the Guandimiao and Wawutang Granitic Plutons in Hunan, South China and Its Petrogenetic Significance 总被引:1,自引:0,他引:1
CHEN Weifeng CHEN Peirong ZHOU Xinmin HUANG Hongye DING Xing SUN Tao The Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing Jiangsu No. Research Institute CNNC Changsh Hunan 《《地质学报》英文版》2007,81(1):81-89
1 Introduction The South China Block (SCB), located between the Qinling-Dabie and Songma Indosinian sutures, experienced successively two important tectonic movements during the Mesozoic, i.e. the Indosinian movement (early Mesozoic) and the Yanshanian movement (late Mesozoic). Therefore, the generally accepted viewpoint is that the key geological problems during the Mesozoic are essentially the dynamics and material expression of these two tectonic movements in South China (Chen et al.… 相似文献
110.
QIAO Xiufu GAO Linzhi PENG Yang 《《地质学报》英文版》2007,81(3):385-397
In the Mesoproterozoic time, the northern part of the Sino-Korean Plate experienced a period of intensive tectonic extension and breakup. 1. An abundance of sedimentary earthquake records is preserved in the Chuanlinggou, Tuanshanzi and Gaoyuzhuang formations in the Mesoproterozoic Changcheng System (1800-1400 Ma) and in the Mesoproterozoic Wumishan Formation of the Jixian System (1400-1000 Ma). These earthquake records are characterized by various liquefied sand-veins, carbonate microspar and coarser spar veins, limestone dikes, liquefied breccia and various forms of liquefied contorted bedding. This deformation is always associated with synsedimentary faults and igneous activity. 2. Three liquefaction models for soft carbonate sediments are recognized, including liquefaction in laminated carbonate rocks, liquefaction in thin-bedded carbonates and large-scale liquefaction along huge carbonate dikes. 3. Based on the record of earthquake and volcanic activities, the Sino-Korean Plate experienced at least twice intraplate breakups. One occurred between 1800-1400 Ma, and the other occurred at about 1200 Ma. The last breakup resulted in formation of the Yan-Liao aulacogen, a tectonic zone characterized by deeper material vibrancy, active faults, major igneous activity and frequent earthquakes. 相似文献