水平井流入控制阀控底水原理及影响因素分析

随着钻完井技术的发展,采用流入控制阀（ICD）完井技术开发底水油藏成为提高产量、降低成本的有效途径。弄清水平井ICD 控底水原理及影响因素成为利用其实现延缓底水锥进、提高油藏最终采收率的关键。在分析ICD 控水限流原理基础上,通过模拟计算,具体分析了流动剖面、环空流动、含水率等3 个影响控水效果的主要因素。分析结果表明：对于不具有高含水段的油藏,可以利用ICD 增大高渗段阻力,从而在牺牲总产液量的基础上降低产水,实现控水;ICD 所产生附加压降有效地减少了环空流动,增强了控水的稳定性,为实现长期稳油控水提供了保障;对储层物性参数分布认识出现偏差将会较大地影响ICD 的控水效果;对于存在高含水段的水平井,需要增大高含水段的附加压降,降低高含水段的产液量,才能有效实现控水。对水平井ICD 控底水原理及影响因素的分析结果为优化水平井ICD完井设计,控制底水锥进提供了技术思路。     

多光谱成像技术在颜色复制方面的应用及发展

由于多光谱成像技术不仅能够获得物体的空间维信息,而且还可以获取物体表面的每一个像素的光谱维信息,因此,应用多光谱成像技术来复制出目标物体的颜色,成为颜色科学这一领域的研究热点.对多光谱成像技术在颜色科学的应用及发展进行了简单的回顾,并指出基于Kubelka-Munk理论的多光谱成像技术复制颜色的算法,会提高反射比低的目标颜色复制的精度,因此这种算法将会有更加广阔的应用前景.     

无残渣纤维素压裂液在苏里格东区致密气藏的应用

无残渣纤维素压裂液体系在酸性条件下实现交联,具有基液配制简单、增黏速度快、无鱼眼、携砂性能好、破胶彻底、无残渣、低伤害及自身防膨等特点,跟羟丙基瓜胶压裂液相比,更适用于易受外来流体伤害的低渗特低渗储层的压裂改造。现成功应用于苏里格东区致密气藏。试验结果表明,该压裂液基液能在2 min达到其最高黏度的97.5%,破胶液表面张力为24.68 m N·m-1,压裂液残渣含量为0,岩心损害率为12.3%,极大降低了对储层和裂缝导流能力的伤害。在苏里格气田进行了现场应用5口井11层(段),压裂效果显著,压后平均日产气量是邻井的2~5倍。     

限域于三维多孔碳的超细纳米尺度Cu2Sb合金用于钠离子和钾离子电池负极

Ultrafine nano-scale Cu₂Sb alloy confined in a three-dimensional porous carbon was synthesized using NaCl template-assisted vacuum freeze-drying followed by high-temperature sintering and was evaluated as an anode for sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). The alloy exerts excellent cycling durability (the capacity can be maintained at 328.3 mA·h·g?1 after 100 cycles for SIBs and 260 mA·h·g?1 for PIBs) and rate capability (199 mA·h·g?1 at 5 A·g?1 for SIBs and 148 mA·h·g?1 at 5 A·g?1 for PIBs) because of the smooth electron transport path, fast Na/K ion diffusion rate, and restricted volume changes from the synergistic effect of three-dimensional porous carbon networks and the ultrafine bimetallic nanoalloy. This study provides an ingenious design route and a simple preparation method toward exploring a high-property electrode for K-ion and Na-ion batteries, and it also introduces broad application prospects for other electrochemical applications.     

自治系统中广义Kuramoto-Sivashinsky方程有限差分解的长时间行为

分析了带全局吸引子的广义Kuramoto-Sivashinsky方程的有限差分格式所生成的离散动力系统的动力性质,在自治系统中得到了有限差分格式的稳定性证明和差分解的误差估计,以及该系统在日H2h空间中全局吸引子的存在性.     

齿轮中心双流传动系统的动力学分析

为了研究滑动摩擦和相位调谐对齿轮中心双流传动动力学的影响,建立了考虑时变啮合刚度、啮合阻尼、齿面摩擦、啮合相位、支承刚度及支承阻尼的齿轮中心双流传动系统扭转-横向振动耦合模型.通过对齿轮副啮合过程的分析,推导了系统中与摩擦有关的计算公式,并采用数值仿真法研究了滑动摩擦、相位调谐对齿轮动态传动误差和支承动载荷的影响.研究结果表明:滑动摩擦对齿轮支承动载荷影响很大,采用相位调谐可有效地降低系统的动态传动误差及中心轮的支承动载荷.     

Highly effective La-deficient La_(1-x)Ce_xMnO_3 mixed oxides for the complete oxidation of methane

La-deficient La_1-xCe_xMnO₃ mixed oxides, obtained by selective dissolution in 1 M nitric acid, were employed in methane complete oxidation. The majority of the La cations in these perovskites were removed, resulting in increased specific surface areas, better reducibility and greater activity. Incorporation of a small amount of Ce stabilized the structure and a perovskite phase persisted in La-deficient La_1-xCe_xMnO₃ mixed oxides af...     

南诏时期的施蛮与顺蛮

南诏时期的乌蛮是一个内涵丰富并处于不断分化发展的民族群体。在其内部,除了被史家记为乌蛮的那部分,尚存施蛮和顺蛮等多个"乌蛮别种"。对于施蛮、顺蛮的研究而言,现有的相关研究成果主要着眼于施蛮、顺蛮的分布、迁徙,对其民族关系、民族文化及社会发展关注较少。从历史人类学的视角对施蛮和顺蛮进行研读和挖掘,既可以拓展乌蛮乃至西南民族研究的视野和内容,也可以为人们了解中国多民族国家形成过程中的多样性和复杂性提供一些生动案例。     

A model-embedded trend test with incorporating Hardy-Weinberg equilibrium information

The genetic models are greatly important in the analysis of genetic epidemiologic studies and many of the studies are conducted using the trend test under the additive model. However, for many complex diseases and traits, the underlying genetic model for a genetic locus is usually uncertain. So a robust test free of genetic model is appropriate. In this paper, the authors propose a model-embedded trend test by incorporating Hardy-Weinberg equilibrium information and obtain the explicit formula to calculate its statistical significance. Extensive simulation studies show the proposed test is more robust than the existing procedures. Finally, a real application is further analyzed to show the performance of the proposed test.