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841.
结合激光技术与现代电子技术,提出一种能够实现非连续回转面径向跳动误差检测的非接触检测方法。  相似文献   
842.
There are abundant natural gas resources in Chinese marine sedimentary basin. The exploration hot shots of natural gas are the Palaeozoic marine strata here in recent years, and several large scale gas fields have been discovered. Chinese Palaeozoic high-post matured and coal measure hydrocarbon source rocks are mainly prone to gas generation in the present. This research considered that gas source rocks and TSR are the key cause of gas enrichment of marine strata. High-quality argillaceous and coal measure hydrocarbon rocks are distributed widely in the Palaeozoic marine strata, which have been in highly matured phase in the present. The argillaceous source rock generally contains various sulfates that could accelerate crude oil cracking to gas for TSR occurrence, and coal measure source rock mainly generates gas, so Chinese marine basin gives priority to accumulating gas. Marine strata have not founded oil reservoirs in the Sichuan Basin and Ordos Basin, and they consist mainly of dry gas. Marine natural gases are the mixed gases of oil cracking gas and coal-formed gas in a general way, oil cracking gases contain usually some H2S and CO2. Hydrocarbon carbon isotopes are very complicated, and methane and ethane isotopic values bear apparent reversal caused by thermal evolution and mixing among different genetic types of natural gas. Coal-formed gases are the main component of Chinese marine natural gas. The Upper Permian of the Sichuan Basin and the Carboniferous-Permian of the Ordos Basin coal measure hydrocarbon source rock present large hydrocarbon generation potential, which are the prospecting highlight of marine natural gas hereafter. Oil cracking gas exploration will be paid much attention to in the Tarim Basin because of the lack of coal measure hydrocarbon source rock.  相似文献   
843.
Generally, there are some anhydrites in carbonate reservoir, as H2S is also familiar in carbonate oil and gas reservoirs. Nowadays, natural gas with high H2S concentration is usually considered as TSR origin, so there is close relationship between H2S and anhydrite. On the contrary, some carbonate rocks with anhydrite do not contain H2S. Recently, researches show that H2S is only a necessary condition of H2S formation. The reservoir porosity, sulfate ion content within formation water, reservoir temperature, oil/gas and water interface, hydrocarbon and some elements of reservoir rock have great controlling effects on the TSR occurrence. TSR deoxidizes hydrocarbon into the acidic gas such as H2S and CO2, and the H2S formation is controlled by TSR occurrence, so the relationship among reaction room, the contact chance of sulfate ion and hydrocarbon, the reservoir temperature has great influence on the TSR reaction. H2S has relatively active chemical quality, so it is still controlled by the content of heavy metal ion. Good conditions of TSR reaction and H2S preservation are the prerequisite of H2S distribution prediction. This paper builds a predictive model based on the characteristic of natural gas reservoir with high H2S-bearing. In the porosity reservoir with anhydrite, the formation water is rich in sulfate and poor in heavy metal ion. Oil and gas fill and accumulate in the gas reservoir with good preservation conditions, and they suffered high temperature later, which indicates the profitable area of natural gas with high H2S-bearing.  相似文献   
844.
西藏措勤地区典中组火山岩地球化学特征及构造背景   总被引:6,自引:0,他引:6  
措勤盆地位于西藏冈底斯构造-岩浆岩带的西段北侧,该区古新世火山活动十分强烈,形成了一套厚度大于1 000 m的中酸性火山岩地层,火山岩K-Ar和Rb-Sr同位素年龄为63.9~61.0 Ma,区域上可与古近纪林子宗群下部层位相对比,归为古新统典中组.火山岩岩石化学、地球化学特征分析表明,该火山岩系属高钾钙碱性-钙碱性系列,轻稀土富集,负Eu异常明显.与原始地幔相比,微量元素Rb,Ba,K,Th,U富集;Ti,P,Sr,Ta(Nb)亏损.锶、氧同位素组成显示岩浆来源与陆壳物质关系密切,推测是来自于俯冲带的幔源基性岩浆与陆壳重熔酸性岩浆以不同比例混合所形成.综合研究认为,这套火山岩形成于陆缘弧构造环境,与喜马拉雅特提斯洋壳向北俯冲消减作用有关.  相似文献   
845.
破碎岩体中的气体渗流规律研究   总被引:1,自引:0,他引:1  
从实际流体的运动微分方程出发,推导得出了破碎岩体中的气体渗流微分方程,并进一步结合流-固耦合理论导出了破碎岩体中的流-固耦合随机微分方程:通过白行设计的试验仪器、试验方法,进行了破碎岩体中的气体渗流试验,得出了不同粒径的破碎砂岩的气体渗透率,并给出了破碎岩体中的渗透率变化规律,丰富了破碎岩体中气体的渗流理论和试验方法,对以后该问题的进一步研究具有一定的参考价值。  相似文献   
846.
计算全息所用的目标数据一般是通过计算机三维软件模拟获得,这样对于计算全息的应用有一定的限制.提出利用三维激光扫描仪获取计算全息图三维数据的方法,研究了计算全息物光分布和扫描三维数据之间的关系,建立了依据三维物体扫描数据的模拟物光波前分布,并分析了立体数据计算全息消隐问题.  相似文献   
847.
采用阴极真空电弧离子沉积技术在硅基片上制备出了MgO薄膜。利用椭圆偏振光谱、原子力显微镜及扫描电子显微镜分别对不同氧流量下制备的MgO薄膜的厚度,光学常数,表面粗糙度及表面形貌进行了分析,并对椭圆偏振光谱的光学粗糙度结果和原子力显微镜的均方根粗糙度结果进行了对比和分析。结果表明,不同氧流量下制备出的MgO薄膜,表面粗糙度及薄膜颗粒随着氧流量的增加而增大。椭偏光谱与AFM得到的表面粗糙度存在线性一致关系,表明椭偏光谱可作为一种很好的无损分析手段。  相似文献   
848.
介绍了用U型管法测定液体表面张力系数的原理和方法。由于采用线阵光电耦合器件(CCD)进行测量,提高了测量精度。  相似文献   
849.
Numerical simulations of granular flows in rotating drums operated at medium to high rates (Fr=0.1― 0.2) have been carried out by using a Molecular Dynamics (MD) algorithm that incorporates inelastic particle interactions, sliding friction and rolling friction. The results indicate that the behavior of granular flow in rotating drums can be classified into two distinct zones: a shear active layer at the bed surface and a quasi-static plug flow region adjacent to the wall. The residence time of a tracer particle in the active layer is approximately a third or a half of that in the plug flow region. The thickness of the active layer at mid-chord is about 0.57―0.61 times that of the plug flow region. It is found that all cases simulated in this work are in the rolling-cascading intermediate regime instead of the pure rolling re-gime. The simulated tangential velocity at the mid-chord is also compared with experimental results reported in the literature and good agreement has been obtained. Based on the MD simulations and experimental results, a continuum approach has also been developed. It is shown that the behavior of granular solids in the plug flow region experiences plastic deformation along the radial direction from the wall with the velocity profiles well described by an exponential function, whereas the active layer velocity follows a simple expression for the Couette shear flow. Discussion has also been made on the granular temperature and concentration profiles.  相似文献   
850.
Clay minerals have played a significant role in the study of the East Asian monsoon evolution in the South China Sea by being able to track oceanic current variations and to reveal contemporaneous paleoclimaUc changes prevailing in continental source areas. As one of the most important rivers inputting terrigenous matters to the northern South China Sea, the Pearl River was not previously paid attention to from the viewpoint of clay mineralogy. This paper presents a detailed study on clay minerals in surface sediments collected from the Pearl River drainage basin (including all three main channels, various branches, and the Lingdingyang in the estuary) by using the X-ray diffraction (XRD) method. The results indicate that the clay mineral assemblage consists dominantly of kaolinite (35%-65%), lesser abundance of chlorite (20%-35%) and illite (12%-42%), and very scare smectite occurrences (generally 〈5%). Their respective distribution does not present any obvious difference throughout the Pearl River drainage basin. However, downstream the Pearl River to the northern South China Sea, the clay mineral assemblage varies significantly: kaolinite decreases gradually, smecUte and illite increase gradually. Additionally, illite chemistry index steps down and illite crystallinity steps up. These variations indicate the contribution of major kaolinite, lesser illite and chlorite, and very scarce smecUte to the northern South China Sea from the Pearl River drainage basin. The maximum contribution of clay minerals from the Pearl River is 72% to the northern margin and only 15% to the northern slope of the South China Sea. In both glacials and interglacials, kaolinite indicates that the ability of mechanical erosion occurred in the Pearl River drainage basin.  相似文献   
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