Toward A Mechanistic Understanding of Re-Infiltration in Naturally Fractured Reservoirs with Surfactant-Aided Gravity Drainage Process

Surfactant-aided gravity drainage is an improved oil recovery technique for water-invaded zone in fractured carbonate reservoirs, which are mostly oil-wet or mixed-wet rocks. The re-infiltration mechanism in water-invaded zone has a considerable effect on oil vertical movement in gravity drainage processes. In this work, a mechanistic understanding of re-infiltration in surfactant-aided gravity drainage, in comparison to oil–water gravity drainage is presented using an experimentally and numerically validated model. A column model is constructed from three matrix blocks. These blocks are separated from each other by horizontal fractures. A storage tank is considered on top of the model to store depleted oil from matrix blocks. The stacked-blocks model for re-infiltration is validated and verified to simulate water and chemical flooding using a mesh independency study and experimental flooding data in a composite core experiment. Using this model, several analyses are performed to investigate effects of rock and fluid properties, rock saturation functions, wettability alteration, surfactant adsorption, and capillary continuity on re-infiltration.     

基于纳米压痕技术的电子玻璃微观力学性能研究

为了研究不同电子玻璃的微观力学性能,采用先进的纳米压痕技术记录钠钙硅、无碱硼铝硅和碱铝硅等典型电子玻璃的载荷-位移曲线,利用Oliver-Pharr方法和经典的弹塑性变形理论,计算玻璃的硬度和弹性模量. 玻璃的硬度主要与结构的键合度相关,平均非桥氧数越高,外力作用下越容易致密化,硬度越小;弹性模量主要取决于质点间的化学键强度,化学键力越强,变形越小,弹性模量越大;九点法测得的弹性模量与硬度的变化趋势不完全相同,借助硬度-弹性模量-能量耗散之间的本征关系,评价玻璃样品的微观均匀性,其中无碱硼铝硅玻璃的恢复阻力大,局部能量耗散大,不容易引起整体破坏,力学性能最好;与浮法工艺相比,溢流下拉法制备样品的局部力学性能波动较小,微观均匀性较好.     

地聚合物混凝土配比及力学性能研究

混凝土是巷道支护过程中的重要建筑材料,然而混凝土在巷道施工中常常出现质量问题,为了不影响正常生产,需要对其进行修补。地聚合物混凝土凝结时间快,早期强度高,界面结合能力强,耐高温性和抗冻性强,耐腐蚀性良好,具有用作修补材料的潜力。以粉煤灰和矿粉为原料,Na₂SiO₃溶液和NaOH为碱激发剂制备地聚合物胶砂,研究不同的碱激发剂模数（1.0、1.2、1.4）和掺量（10%、15%、20%）对不同龄期胶砂力学性能的影响。结果表明：当碱激发剂模数为1.2,碱掺量为15%时,胶砂强度达到最大值。设计正交试验,研究了不同水胶比（0.45、0.50、0.55）、粉煤灰掺量（30%、50%、70%）和砂率（30%、35%、40%）对不同龄期地聚合物混凝土的工作性能和力学性能的影响。结果表明：粉煤灰掺量对抗压强度影响最为显著,水胶比次之,而砂率对强度发展几乎没有影响。最优的配合比为水胶比为0.50,粉煤灰掺量为50%,砂率为35%。     

回火处理对Fe-Mn基合金剪切模量的影响SCIEI

研究了回火温度和时间对两种成分Fe-Mn基合金剪切模量的影响。结果指出,附加Cr,Ti的合金在回火状态下ΔG G-T曲线有极小和极大两个极值,而附加Cr,Ni,W,C的合金只呈现极大值特征。这是由于Ni,W,C降低反铁磁转变点T_N造成的, 随着回火温度升高或回火时间增加,ΔG_λ效应逐渐增加。     

CHARACTERISTICS OF INTERNAL FRICTION AND MODULUS ASSOCIATED WITH NON-EQUILIBRIUM DIFFUSION-TYPE PHASE TRANSFORMATION IN EUTECTOID Al-Zn ALLOY

The characteristics of the low frequency internal friction and the modulus effect associatedwith the non-equilibrium spinodal pretransformation and the following discontinuous trans-formation was investigated in an as-quenched eutectiod Al-Zn alloy.It was observed that theloss of the stability in the lattice,which corresponded to the large-amplitude long-wavelengthstatic concentration wave in the non-equilibrium spinodal pretransformation,did not induceany effect of localized soft modulus.Although there are two aging internal friction peaks inphase transformation which correspond to the appearance and disappearance of the coherencyin spinodal pretransformation and the maximum of the interface area in the discontinuoustransformation respectively,the effect of localized soft modulus did not take place yet.     

压入深度与膜厚对薄膜与基体复合硬度及弹性模量的影响

根据高华建的复合弹性模量模型，提出了用一个测点的载荷-位移曲线计算整个压入深度内薄膜和基体复合硬度分布的方法，探讨了压入深度与膜厚对硬度与弹性模量测量值的影响，指出可由膜-基复合性能反推膜本身的性能。     

熔模铸造型壳抗弯弹性模量的研究

依据材料力学、陶瓷材料的有关理论和方法,分别对水玻璃型壳、硅溶胶型壳及其复合型壳在不同温度时的抗弯弹性模量进行了测试研究.结果表明,耐火材料、温度对型壳的弹性模量有较大的影响,硅溶胶型壳和复合型壳的弹性模量值比水玻璃型壳的大.     

Effect of cold spray deposition of a titanium coating on fatigue behavior of a titanium alloy

The deposition of titanium on a titanium alloy substrate is being examined for potential use as a surface treatment for medical prostheses. A Ti6Al4V alloy was coated with pure titanium by cold gas dynamic spraying. Coatings were deposited onto samples with two different surface preparation methods (as-received and grit-blasted). The fatigue life of the as-received and grit-blasted materials, both before and after coating, was measured with a rotating-bend fatigue rig. A 15% reduction in fatigue endurance limit was observed after application of the coating to the as-received substrate, but no significant reduction was observed on its application to the grit-blasted substrate. The reduction in fatigue endurance limit has been related to the substrate-coating interface properties, the elastic modulus, and the residual stress states. This article was originally published inBuilding on 100 Years of Success, Proceedings of the 2006 International Thermal Spray Conference, (Seattle, WA), May 15–18, 2006, B.R. Marple, M.M. Hyland, Y.-Ch. Lau, R.S. Lima, and J. Voyer, Ed., ASM International, Materials Park, 2006.     

在纳米压入仪上进行悬臂梁法测量弹性模量的影响因素分析

对在纳米压入仪上进行悬臂梁法测量弹性模量的主要影响因素进行了综合分析,主要包括加载系统悬置弹簧刚度、压头压入、梁沿截面宽度方向挠曲、梁支座附加挠曲等影响。在考虑这些因素的基础上,得到了悬臂梁的有效挠度,利用有效挠度与载荷之间的关系,评价悬臂梁材料的弹性模量。对单晶硅(100)悬臂梁试样进行了实验,得到其弹性模量为155GPa±9.5%GPa,与参考文献值符合较好。表明在纳米压入仪上进行悬臂梁法测量,只有综合这些影响因素后,才能获得有效、准确的弹性模量测量结果。     

Some new operational modes and parameters of stress relaxation for the viscoelastic characterization of solid polymers. III. The area ratio mode and the intrinsic “strain–clock” function

The introduced area ratio mode of operation with its corresponding parameters seems to have a fairly high sensitivity to the viscoelastic response of the solid polymer. This appeared from the fact that a good distinction among the linear viscoelastic, the nonlinear viscoelastic, and the viscoplastic ranges of behavior can be made. By using a relevant rheological modeling and its corresponding algorithmical approach, in the case of isotactic polypropylene, this material can be characterized as a morphological three‐phase material consisting of an intraspherulitic crystalline, an amorphous phase, and a interspherulitic para‐crystalline phase. In this sense, the material was simulated using two models: the Poynting–Thomson and the Maxwell–Wierchert, from where a good response of the material to the first model appeared. The so‐called intrinsic “strain–clock” function and its corresponding coefficient of strength of nonlinear viscoelastic behavior, which were relieved by the experimental data, seem to be some powerful and very practical “tools” that can give a proven suplementary characterization of the material. Finally, by this intrinsic function, the existence of permanent internal stresses, was confirmed, in an indirect way, which was mentioned in part II of this study. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 149–158, 2003