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41.
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   
42.
3维地理信息系统技术综述   总被引:22,自引:1,他引:22  
文中对3维地理信息系统技术进行综述性介绍,扼要地讨论了国内外有关3维地球空间信息的获取、管理、分析与可视化等技术的进展与动态,并分别探讨了它们的优势和局限。  相似文献   
43.
This paper presents the technical basis for wide area real time decimetre positioning services using multiple carrier signals transmitted by future GNSS such as modernized GPS and Compass systems. The first step is to form two ionosphere-reduced extra-widelanes (EWL) that have the minimal total noise levels in cycles, considering the effects of the ionospheric and tropospheric delays, orbital error, and phase noise terms in various observational environments. The proposed three carrier ambiguity resolution ...  相似文献   
44.
风沙流中沙粒浓度分布的实验研究   总被引:9,自引:0,他引:9  
利用粒子图像测速技术(PIV),在风洞内对与天然沙接近的石英沙风沙流沙颗粒浓度沿高度分布进行了研究。对 3种不同轴线风速研究结果表明,风沙流中沙粒浓度沿水平方向基本不变,而随高度呈指数衰减,而且其衰减速率与风速密切相关。风速越大,衰减速率越慢;风速越小,衰减速率越快。风沙运动一旦发生时,靠近沙床表面的沙粒浓度随风速变化很小,可以认为趋于稳定,达到最大值。  相似文献   
45.
对柴达木盆地东部地区侏罗系大煤沟剖面、绿草山剖面进行了露头取样,并利用Rock-Eval生油岩评价仪、色谱—质谱仪、稳定同位素质谱仪等实验分析测试技术对样品进行了地球化学特征分析。实验结果表明,样品有机碳含量变化从0.07%到56.8%,有机质类型以Ш型有机质为主,少数为型有机质,极少数为型有机质,灰黑色油页岩及黑色炭质页岩是侏罗系中的优质烃源岩。检测样品C29甾烷异构化参数C29αββ/(αββ ααα)、C29ααα20S/(20S 20R)分布范围分别为0.25~0.35、0.06~0.34,处于未熟—低熟状态。侏罗系水体环境较浅,多为滨浅湖与沼泽环境,具有煤系烃源岩特点,局部为水体比较咸化的半深湖—深湖环境。  相似文献   
46.
Three Cenozoic basins-the Qaidam basin, the Weihe graben-type basin and the North China plain-which are different in climatic conditions, geological settings and run-off types, are selected for the study. Based on an analysis of background information of the transect along the middle-latitude region, studies of groundwater dynamics, geochemistry, simulation of water circulation of the main elements as well as isotopic chronology, the information on global changes is collected, the formation of groundwater circulation systems and their evolution under stacked impacts of natural conditions and human activities are discussed, and a correlation is made between the evolutionary features of the above systems in these basins since 25 ka B.P. All these have laid a good foundation for further generalizing the evolutionary model of land water in northern China.  相似文献   
47.
Introduction Houhan Shu?ZHANG Heng Biography written by FAN Ye(AD398?AD445,South-North Dynasties)described about the response of ZHANG Heng’s Seismometer to Longxi earthquake as follows.“On one occasion a dragon dropped a ball without an earthquake being felt.All the scholars in the capital blamed this effect happening without any feelings of the earthquake.Several days later,a messenger arrived reporting that an earthquake really had taken place at Longxi.There-upon people all a…  相似文献   
48.
Based on the information of geology, geochemistry, geophysics and remote sensing, the GIS of multi-source information is used to evaluate Cu, W and Au mineral resources in Northern Qilian, China. As the GIS evaluation system works out in the thinking of geological prospecting, its functions include file management, graph edition, database maintenance, information inquiry and comprehensive spatial analysis as well as prospecting target prognosis. Accordingly, the GIS evaluation system can be used directly and conveniently for inquiry and analysis of visual graphs or images.  相似文献   
49.
According to topography of Yemen,most areas and villages are located at obligated crest,toe of mountain and under cliffs.Therefore Al-Huwayshah consisting of Tawilah sandstone group is characterized by steep slope reach to 90° in some areas.This area is affected by strong tectonic movements and faults that occurred during the geological epochs.This effect enhances to find out fractures and joints as well as the rocks become brittle and ready to slide depending on the position of area.And there are some frac...  相似文献   
50.
About forty productive oil/gas fields hosted in volcanic reservoirs have been found since 1957 in fourteen basins of China. They can be simply subdivided into two groups, the east and the west. Reservoir volcanic rocks of the east group are predominantly composed of Late Jurassic to Early Cretaceous rhyolite and Tertiary basalt, preferred being considered as rift type volcanics developed in the circum-Pacific tectonic regime. Those of the west are Permo-Carboniferous intermediate/basic volcanic rocks, being island-arc type ones developed in paleo-Asian Ocean tectonic regime.  相似文献   
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