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51.
A mathematical model of primary oil migration as a separate phase out of compacting shales is presented. During burial and oil generation, source rock porosity decreases and oil saturation increases until residual oil saturation is reached. At this stage oil is expelled out by capillary and excess fluid pressure gradients. The model is a system of differential equations which relate changes in oil and water saturation in time to water and oil flow out of the source rock during burial. An additional set of equations for periods of erosion of overburden are also provided. The equations can be numerically solved by finite difference method. If oil and water flow is to be simulated during oil generation, then at each time step, changes by oil generation in oil and water saturations and porosity must be calculated. The solution procedure is briefly outlined. 相似文献
52.
Nowadays there are some chronic serious environmental problems, such as eutrophication, blue tide and so on, in a complicated coastal zone or a semi-enclosed bay, because the water exchanges between an inner bay and an outer sea is weak compared with the supply of contaminant. Under this situation, a method to improve the water quality by 3-dimensional small unsymmetrical structures has been proposed by Komatsu et al. In this paper, several numerical simulations of the tidal current and concentration for various arrangements of bottom roughness in a semi-enclosed model bay are carfled out with a depth-averaged 2-D numerical model. The model is solved by the hybrid finite analytic method with nonstaggered grid. And the SIMPLES algorithm with Rhie and Chow' s momentum interpolation technique is used for the simulation. The effect of Komatsu' s method for water purification is examined by numerical simulation. The result of numerical experiment indicates that it is possible to generate a new tidal residual current and to activate a tidal exchange by bottom roughness arrangement only. 相似文献
53.
Abstract. The temperate, symbiotic coral Cladocora caespitosa occurs naturally with variable numbers of zooxanthellae. This allows us to study differences in the physiology of symbiotic and "non-symbiotic" polyps and to correlate them with zooxanthellae activities.
Zooxanthellae density in "dark" (normal-colored) polyps was 50 times higher than in "white" (bleached) polyps.
The chlorophyll a content per zooxanthella was 3 times, and Chi c was 13 times higher in white polyps than in dark ones. O2 -flux experiments were conducted with colonies in situ and with single polyps - dark and white - under laboratory conditions. Two approaches were used to evaluate the contribution of zooxanthellae translocation products to animal respiration. Both revealed that the animal tissues derive a higher benefit from the zooxanthellae during periods of low water temperature than during warm periods. 相似文献
Zooxanthellae density in "dark" (normal-colored) polyps was 50 times higher than in "white" (bleached) polyps.
The chlorophyll a content per zooxanthella was 3 times, and Chi c was 13 times higher in white polyps than in dark ones. O
54.
本文对北部湾三维潮波进行了数值研究,并将所得结果与现有观测资料作了比较。通过比较发现两者相当一致。文中还绘制了M_2和K_1分潮的同潮图,并对其作了讨论。可以断定,北部湾的日潮优势是由日潮共振所引起的。M_2和K_1分潮流的水平分布表明,强流区位于它们各自的蜕化无潮点附近。还讨论了分潮流的铅直结构,可以看出这种结构十分接近实际分潮流场的特征。 相似文献
55.
北黄海沉积物——水界面反硝化速率及影响因素研究 总被引:4,自引:0,他引:4
探讨近海氮的循环机制,采用乙炔抑制法和现场静态箱法对北黄海夏季局部海域的反硝化速率进行了研究,该海域反硝化速率在2.5~5.8μmol/m2.h之间,平均4.85μmol/m2.h。影响其反硝化速率的主要因素为溶解氧,其次是温度。北黄海的反硝化速率低于珠江口和长江口海域。 相似文献
56.
分层流体中内孤立波在潜浮式竖直薄板上透射和反射 总被引:2,自引:0,他引:2
采用边缘层理论研究了两层流体系统中内孤立波在潜浮式竖直薄板上的透射和反射问题,提出了非线性演化方程的“初值”条件,分析了内孤立波与薄板非线性相互作用的效应。研究表明:流体层的密度比以及薄板伸入上下层的深度对于反射和透射波结构具有显著的影响,薄板伸入下层越深、密度差越小,则薄板阻碍孤立波透射的效率越高;透射波通常演化为单峰孤立波和迅速衰减的尾波,反射波演化为缓慢衰减的尾波列;对于具有小密度差的跃层结构,内孤立波在潜浮式竖直薄板上的透射及其演化近乎是无障碍的。 相似文献
57.
Andrey Andreev Makio Honda Yuichiro Kumamoto Masashi Kusakabe Akihiko Murata 《Journal of Oceanography》2001,57(2):177-188
Excess CO2 and pHexcess showing an increase in dissolved inorganic carbon and a decrease in pH from the beginning of the industrial epoch (middle of the 19th century) until the present time have been calculated in the intermediate water layer of the northwestern Pacific and the Okhotsk Sea. It is concluded that: (1) The Kuril Basin (Okhotsk Sea) and the Bussol' Strait areas are characterized by the greatest concentrations of excess CO2 at isopycnal surfaces due to the processes of formation and transformation of intermediate water mass. (2) The largest difference in excess CO2 concentration between the Okhotsk Sea and the western subarctic Pacific (about 8 µmol/kg) is found at the = 27.0. (3) The difference in excess CO2 between the western subarctic Pacific and subtropical regions is significant only in the upper part of the intermediate water layer ( = 26.7–27.0). (4) About 10% of the excess CO2 accumulation in the subtropical north Pacific is determined by water exchange with the subarctic Pacific and the Okhotsk Sea. 相似文献
58.
本文以~3H—TdR掺入法观察911对小鼠脾淋巴细胞增殖反应的影响并用CTLL细胞检测了其对IL—2的作用。体外实验结果表明,911对小鼠脾淋巴细胞增殖反应有明显的增强作用,以0.5μg/ml的浓度效果最为明显,相对增殖指数RPI可达200%;体内实验则以5mg/kg体重ip,连续7d效果最好,相对增殖指数RPI可达176%;911用药组小鼠IL—2的产生量均高于对照组,以5mg/kg和10mg/kg效果最好。以上实验证明,这一多糖是一种有希望的新免疫调节药物。 相似文献
59.
60.
根据内蒙古孪井滩灌区的自然地理、地质和水文地质条件,在室内外模拟试验的基础上,利用VS2DT模型对灌溉入渗水的运移进行了模拟,计算了现有灌溉量下的渗漏量,提出了灌区春小麦和夏玉米的节水灌溉模式。春小麦第一次灌溉的节水灌溉量为150 mm,第二次灌水的节水灌溉量为97.5 mm,以后4次灌水的灌溉量在60~75 mm之间。夏玉米第一次灌水的灌溉量也以150 mm为宜,以后5次灌溉量分别以127.5 mm,90.0 mm,97.5 mm,82.5 mm及67.5 mm为宜。此灌溉模式不仅能够节约水资源,而且能够防止土壤次生盐渍化的发展。 相似文献