Numerical Simulation of Drag Partition over Rough Surfaces

We present a numerical simulation of drag partition over rough surfaces. A computational fluid dynamics model is applied with high resolution to simulatingturbulent flows over arrays of roughness elements positioned on asmooth surface. The skin drag on the surface and the pressure drag on the roughnesselements are computed. The simulated drag partition compares well with wind-tunnelmeasurements and theoretical estimates for similar rough surfaces. This confirms that the computational approach offers an alternative to wind-tunnel and field experiments in studying drag and drag partition. The model is then applied to studying drag partition over rough surfaces with various roughness configurations. It is shown that drag partition depends not only on the magnitude of the roughness frontal area but also on the sizes and arrangement of roughness elements, because (1) the pressure drag coefficient is sensitive to roughness-element dimensions and (2) the arragement of roughness elements lead to different interferences of turbulent wakes. The impact ofthe latter factor is not insignificant.     

科学计算可视化技术的研究与应用

本文介绍了科学计算可视化技术的发展和应用情况，论述了这一新技术的特点及其在油气藏描述，工程设计ＣＡＤ等学科的应用和发展趋势。阐述了目前国际国内计算机图形学领域具体的研究方向和方法及图形软件、图形硬件的发展概况。     

氡迁移的接力传递作用

在扩散和对流等作用的基础上，提出了用于解释氡法探寻深部矿藏、预报地震和研究地球动力学带等方面的氡迁移的接力传递作用．这种作用可能是镭传氡和氡传氡，也可能是借助于其它的物质或自然力来传递，传递方式有二棒接力和多棒接力．扩散和对流等10多种作用．一般地说，只能使氡气作短距离的迁移，而接力传递作用则可以解释氡作长距离的迁移．     

弹性波有限元逆时偏移技术研究

改善弹性波有限元逆时偏移剖面的质量是目前该方法面临的难题，为此，首先在有限元方程中，合理地加入边界力项，并找到准确的成像条件，以及对炮集资料用惠更斯（Huygens）原理消除直达波和面波干扰等措施，提高了复杂含油气结构的偏移剖面质量．本文重点研究单分量资料弹性波偏移的可靠性，利用单分量、抽炮集资料，模拟实际资料处理典型含油气构造，得到了高质量的自激自收和炮集资料的偏移剖面．     

松潘—甘孜造山带中丹巴地区变质岩的流体包裹体研究

对丹巴地区动热变质岩石英中的流体包裹体研究表明，第一类型包裹体为高密度CO2包裹体，与深层滑脱作用密切相关，其温度、压力可代表变质峰期的温压条件。第二类型包裹体为CO2－H2O包裹体，H2O含量增加，与变质峰期后的抬升作用有关。第三类型包裹体为NaCl－H2O包裹体，以H2O为主，与抬升作用引起的退变质作用有关。其形成温度依次降低，说明它们是在变质作用的不同阶段捕获的。     

对煤中锗矿化若干问题的思考——以临沧锗矿为例

本文在综述煤中锗矿化国内外研究现状的基础上，以临沧锗矿为例，深入讨论了在煤系地层中形成超大型独立锗矿床的特殊条件。结果表明，煤是锗成矿极有利的围岩，煤能否富集锗主要取决于有无富锗流体与煤相互作用。     

冀西北东坪金矿床成矿流体的来源研究

冀西北东坪金矿床成矿流体的来源研究＊莫测辉王秀璋程景平梁华英（华南农业大学资源环境学院，广州５１０６４２）（中国科学院广州地球化学研究所，广州５１０６４０）关键词金矿床成矿流体来源岩浆热液大气降水热液侵入岩体中的金矿床乃至岩体接触带或附近地层中的金矿...     

铂族元素迁移富集机理的新探

在岩浆及高温热液中，拍族元素以纳米液态铂族元素单质、铂族元素与其它金属元素的纳米液态合金、纳米液态铂族元素的硫、砷化物迁移。在中、低温热液及表生条件下，除呈上述固态纳米铂族矿物随流体迁移外，还呈配合物形式迁移。然后它们在合适的条件下沉淀富集形成矿床。此外，还讨论了铂族元素与金地球化学条件的异同。     

Constraints of Housing Age and Migration on Residential Mobility

This paper investigates the role of housing age in constraining residential mobility, measured as the percent of households that have moved into their homes in the past 15 months. The leading explanation for why mobility rates differ so much among regions of the United States has been the overall level of growth. The present analysis shows that the growth effect operates through both the newness of population (migration) and the newness of housing available for occupancy by all local residents. The posited explanation for this housing age effect is that progressively older units contain increasingly settled occupants, yielding fewer opportunities for in-movers in areas with older housing. It is empirically demonstrated that households in older housing have lower likelihood of recent mobility even after controlling for age, tenure, migration status, and state location of residence. The analysis reveals the temporal interdependency of mobility, migration, person age, and housing age.