Pickering乳液在油基钻井液中的应用

Pickering乳液以其较高的聚并稳定性、多样性、可调控性、低成本、低毒性和生物兼容性等优势,广泛应用于生物医学、食品和化妆品等领域。近年来,Pickering乳液在石油行业的应用备受关注。分析了Pickering乳液的稳定机理与其相较于传统乳液的优势;探究了影响Pickering乳液稳定性的诸多因素及调控方式;最后综述了近年来国内外Pickering乳液在钻井和驱油方面的应用,并对Pickering乳液在石油行业中的发展前景进行了展望。      

高硅铝合金缸套材料摩擦磨损性能研究

采用坦克专用机油,分别加载100N、200N、800N,在不同时间条件下进行喷射沉积高硅铝合金与军用大功率发动机钢缸套材料的对比摩擦学性能试验、模拟发动机工况条件的摩擦配副试验．结果表明,高硅铝合金比钢缸套材料具有更优越的摩擦学性能．高硅铝合金的摩擦学机制分析表明,软基体上分布的高硬度质点相具有决定性作用,摩擦发生时高硬度质点相起到耐磨与支撑作用,软基体磨下的凹坑具有储油与润滑作用．磨痕分析表明,高硅铝合金中的高硬度质点能将42MnCr52钢基表面磨出划痕,证明了高硅铝合金中高硬度质点相的摩擦学作用．     

The shift in US oil demand and its impact on OPEC's market share

Tremendous political pressure is being exerted on the US government by different political parties to diversify its sources of foreign oil supplies by switching from the reliance on OPEC's oil to that originating from non-OPEC nations. Without a doubt, such a shift would adversely impact the market share of some OPEC members, particularly Saudi Arabia, Venezuela and Nigeria. These countries should therefore consider seriously the negative impact of this scenario and consequently formulate individual or joint production policies aiming at protecting their oil market share. To help OPEC achieve this objective, there is a need to estimate the demand function of US oil imports. This paper proffers an estimate of such a function, taking into account, among other variables, the impact of US Strategic Petroleum Reserve (SPR).     

钢质薄壁缸套和膜式煤气表外壳成型工艺分析及计算

介绍了内燃机的钢质薄壁缸套圆筒形拉伸、翻边工艺和膜式煤气表外壳的盒形成型工艺,并通过计算公式确定出相应的工艺尺寸。     

汽缸中分面孔加工工艺研究

介绍了汽缸中分布螺孔的加工方法,提出了保证加工质量的具体措施。     

变壁厚筒形构件辊挤成形过程数值模拟

为解决变壁厚筒体构件制造过程材料利用率低、机加工时长等问题,提出一种辊挤成形工艺。该工艺通过3个被动旋转辊轮的辊压作用实现坯料的塑性变形。借助Deform-3D软件建立变壁厚筒形构件辊挤成形热力耦合刚黏塑性有限元模型,对辊挤过程进行数值模拟,获得了辊挤过程中载荷-行程曲线、等效应力与应变场以及温度场的分布规律。研究了工艺参数对成形构件变形均匀性的影响。结果表明:工件变形的不均匀性随着辊挤速度和摩擦因数的增大而增大,随变形温度的升高而减小。     

高硅铝合金缸套材料腐蚀加工技术研究

采用三维视频显微金相技术对高硅铝合金缸套材料的组织构成、颗粒尺寸以及碱腐蚀深度进行测试与评价;用激光共聚焦显微镜技术对碱腐蚀界面颗粒凹凸以及表面纹理进行观察与描述;用往复式摩擦磨损实验机对碱腐蚀试样进行摩擦学性能评价。结果表明:高硅铝合金组织中主要由硅颗粒及第二相硬质点颗粒构成,平均硅颗粒尺寸为4.00μm,平均第二相颗粒尺寸为3.05μm;随腐蚀时间、深度的增加,腐蚀界面区域增大,表面凸凹及纹理更加清晰,当碱的质量分数为5%,溶液温度为40℃,腐蚀时间为30~40 s,摩擦学性能最优越。     

单缸柴油机滑动轴承润滑的计算机仿真

针对单缸柴油机使用的滑动轴承的润滑设计问题,采用计算机对它的润滑性能进行了仿真.通过编程计算了滑动轴承的油膜厚度、油膜压力、摩擦功耗、润滑油流量、温度等参数.结果表明,通过仿真得到润滑性能数据,可实现提前对单缸柴油机滑动轴承的润滑特性进行预测,能够提高润滑设计的可靠性,具有较高的实用价值.     

基于FLUENT的机动管线泵机组发动机气缸数值模拟

建立了发动机气缸与活塞的三维简化模型并对其进行了动网格划分,应用FLUENT对发动机气缸内的气体压缩及膨胀过程进行了仿真模拟,对气缸温度及压力进行了数值分析,得出了发动机气缸温度变化曲线图及温度、压力变化云图,分析比较了仿真模拟数据与数值计算数据,对模型的准确性进行了验证。     

Assessing the impact of oil prices on firms of different sizes: Its tough being in the middle

Recent empirical research has found evidence of a relationship between oil price movements and stock prices. Most published research investigates the relationship between oil price movements and stock prices using either economy-wide measures of stock prices or industry sector measures of stock prices. An important question that has largely gone unanswered relates to the relationship between oil prices and stock prices when the size of firms is allowed to vary. Relative to large firms, do oil price movements have larger or smaller impacts on the stock prices of small- or medium-sized firms? The answer to this question could have important policy implications that affect economic growth and prosperity. In this paper, a panel of firms is followed over a 17-year period to investigate the relationship between oil price movements, firm size, and stock prices. Evidence is found that shows the relationship between oil price movements and stock prices does vary with firm size and the relationship is strongest for medium-sized firms.