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91.
陈津民 《贵州地质》2006,23(3):244-246
泰来环试验正好说明水下有压力,而不是李泰来先生认为的水下没有静水压力,地下没有静岩压力。  相似文献   
92.
四川盆地川东地区石炭系储产层下限标准的确定方法   总被引:6,自引:0,他引:6  
周文  费怀义 《矿物岩石》1999,19(2):31-36
影响容积法储量计算精度的因素之一是储层的有效厚度取值。有效储层厚度确定得准确与否,主要与下限标准定得是否合理有密切关系。本文通过对川东地区石炭系储层特征的综合研究,结合测井、测试资料,对石炭系储层下限标准的确定方法进行了归纳分析,提出了浮力-毛细管阻力法及相渗透率-产量法两种新的储层下限确定方法,并对各种方法进行分析,推荐了较好的确定裂缝-孔隙型碳酸盐岩储层下限标准的方法。  相似文献   
93.
Cohesive Sediment Transport in the Jiaojiang River Estuary, China   总被引:1,自引:0,他引:1  
Extensive data were obtained of the water and fine sediment dynamics during spring tides in the extremely turbid Jiaojiang River estuary at spring tides. These data enabled the calibration of a two-dimensional (2-D) width-integrated model. Four processes dominated the mud dynamics. These were, firstly, the formation at slack tide of soft mud deposits with an erosion constant much smaller than that of the underlying compacted sediment, secondly the sediment-induced buoyancy effects, thirdly the collapse of the turbulence by the sediment suspension in the fluid mud range and fourthly the inflow of sediment at the mouth of the estuary. These findings demonstrate the necessity to have detailed field data to enable quantitative, as opposed to qualitative, modelling of mud dynamics in turbid estuaries. The estuary is infilling with sediment from the East China Sea and not from riverine inflow, this sediment presumably originates from the Yangtze River located 200 km further north.  相似文献   
94.
朱红钧  黄栏  高岳  唐堂 《海洋工程》2024,(3):107-118
由于氢气密度低,泄漏后的掺氢天然气在海洋波流作用下的浮升扩散行为有别于纯天然气,其泄漏扩散规律有待明晰。利用计算流体力学方法数值模拟了波流联合作用下掺氢输气海管泄漏扩散的过程,结果表明气体泄漏的过程可分为泄漏初期、向上浮升以及横向迁移3个阶段。当掺氢比φH2 <50%时,氢气泡的运动轨迹受天然气泡的影响显著。气体浮升高度和扩散直径的变化与时间成正相关,且随着掺氢比的增大,泄漏气体到达液面所需的时间延长。天然气泡和氢气泡直径在上升的过程中都逐渐增大,两者的浮升速度随浮升高度的增加先增大后减小,天然气泡的浮升速度衰减更快。氢气泡直径随掺氢量的增加而增大,天然气泡直径随掺氢量的增大而减小,两者的上升速度随着掺氢量的增大都表现出先增大后减小的趋势,且氢气泡的上升速度大于天然气泡的上升速度。波长和海流流速越大,泄漏气体的扩散直径越大。  相似文献   
95.
海水所含盐量标志海水浓度,通常以盐度表示,现代“盐度”单位已由专一海洋学领域扩展到盐化工、水产养殖、生态网络调查等学科中,并已产生了重要影响.历史上,盐度的定义和测定方法几经变革[1,2],人们一直在深化自己的认识,探索盐度的实质,笔者在科研实践中认识到:现行国际“实用盐标”及先前“氯度盐标”,应用于保守性质海水样品准确,而应用于非保守性质样品时不准确,其表现特征是两盐度测定值均偏离样品绝对盐度SA,且无重复性.  相似文献   
96.
在导管架下水运动过程中,其组成杆元相对于海平面的位置复杂多样。在导管架下水参数计算和仿真时,为了计算导管架的浮力和浮心,经常采用估算的方法,由于误差比较大而影响了计算和仿真的精度。分析了导管架下水运动过程中杆元的各种状态,用解析的方法推导出导管架下水运动过程中的浮力和浮心的精确计算公式,提高了导管架下水参数计算及其模拟的精度。  相似文献   
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99.
The atmospheric boundary-layer (ABL) depth was observed by airborne lidar and balloon soundings during the Southern Great Plains 1997 field study (SGP97). This paper is Part I of a two-part case study examining the relationship of surface heterogeneity to observed ABL structure. Part I focuses on observations. During two days (12–13 July 1997) following rain, midday convective ABL depth varied by as much as 1.5 km across 400 km, even with moderate winds. Variability in ABL depth was driven primarily by the spatial variation in surface buoyancy flux as measured from short towers and aircraft within the SGP97 domain. Strong correlation was found between time-integrated buoyancy flux and airborne remotely sensed surface soil moisture for the two case-study days, but only a weak correlation was found between surface energy fluxes and vegetation greenness as measured by satellite. A simple prognostic one-dimensional ABL model was applied to test to what extent the soil moisture spatial heterogeneity explained the variation in north–south ABL depth across the SGP97 domain. The model was able to better predict mean ABL depth and variations on horizontal scales of approximately 100 km using observed soil moisture instead of constant soil moisture. Subsidence, advection, convergence/divergence and spatial variability of temperature inversion strength also contributed to ABL depth variations. In Part II, assimilation of high-resolution soil moisture into a three-dimensional mesoscale model (MM5) is discussed and shown to improve predictions of ABL structure. These results have implications for ABL models and the influence of soil moisture on mesoscale meteorology  相似文献   
100.
Using the sounding data of wind, temperature, and humidity in the boundary layer and micrometeorological data on the earth's surface observed in the same period in Dunhuang arid region of Northwest China,this paper researches characteristics of potential temperature, wind, and humidity profiles, confirms the structure and depth of thermodynamic boundary layer in Dunhuang region, and analyzses the relationship of depth of thermodynamic boundary layer with surface radiation, buoyancy flux as well as wind speed and wind direction shear in the boundary layer. The results show that the maximum depth of diurnal convective boundary layer is basically above 2000 m during the observational period, many times even in excess of 3000 m and sometimes up to 4000 m; the depth of nocturnal stable boundary layer basically maintains within a range of 1000-1500 m. As a whole, the depth of atmospheric boundary layer is obviously bigger than those results observed in other regions before. By analyzing, a preliminary judgement is that the depth of atmospheric thermodynamic boundary layer in Dunhuang region may relate to local especial radiation characteristics, surface properties (soil moisture content and heat capacity) as well as wind velocity shear of boundary layer, and these properties have formed strong buoyancy flux and dynamic forcing in a local region which are fundamental causes for producing a super deep atmospheric boundary layer.  相似文献   
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