原油/碱水相互作用热力学

从化学平衡、相平衡原理和Gouy-Chapman扩散双电层理论建立了原油/碱水体系表面活性剂的吸附等温式和界面张力及界面电势方程。测定了大港油田羊三木原油与碱水的界面张力和Zeta电位。结果表明,原油/碱水界面表面活性剂的吸附量虽随水相中NaOH和NaCl浓度而变化,但本质上取决于水相中就地生成的表面活性剂的吸附自由能和表面活性阴离子与其反离子的活度积。碱水中加入NaCl可在低碱浓度时大大促进界面吸附但使界面电势显著下降。理论预测结果与实验结果较为符合。     

Finite element analysis of effect of interfacial bubbles on performance of epoxy coatings under alternating hydrostatic pressure

The stresses around bubbles formed on a coating/substrate interface under hydrostatic pressure(HP)and alternating hydrostatic pressure(AHP)were calculated using the finite element method.The results reveal that HP promotes coating failure but does not mechanically destroy the interface,whereas AHP can provide tensile stress on bubbles formed at the interface and accelerate disbonding of the coating.Because of water resistance,a lag time exists for the coating that serves in an AHP environment.The coating can have a better protective performance if the lag time suits the AHP to minimize the impact of the AHP on the interface.     

接枝马来酸酐对聚乙烯板缝隙液体渗流的影响

用马来酸酐对聚乙烯（PE）进行接枝,制得马来酸酐接枝聚乙烯（PE-g-MAH）,进而制备2组PE板缝隙渗流装置和2组PE-g-MAH板缝隙渗流装置。以蒸馏水和丁酸辛酯为流体,计量各缝隙渗流装置的渗流速度,研究接枝马来酸酐对聚乙烯板缝隙的液体渗流的影响。实验表明;当丁酸辛酯渗流时,接枝马采酸酐对PE板缝隙渗流装置的液体渗流的影响不大,而蒸馏水渗流时,由于马来酸酐基团在界面的富集,降低了水和PE的界面张力。接枝马来酸酐明显地提高了PE板渗流装置液体渗流的速度。     

Gemini型表面活性剂三元复合体系性能和驱油效果

以胱氨酸钠和油酰氯为原料,通过一步反应合成了一种新型阴离子Gemini表面活性剂二油酰胺基胱氨酸钠(Sodium dioleoylamino cystine,SDOLC),利用Texas-500C型界面张力仪和MCR301流变仪研究了Gemini型表面活性剂/HPAM/碱三元复合体系降低油水界面张力性能和黏弹性能,在均质和非均质岩心中评价了体系的驱油效果。结果表明,HPAM的加入不影响Gemini表面活性剂和碱复合溶液与原油界面张力最低值,但可以有效增加体系的黏度。综合考虑界面张力和黏弹性能,选择黏度44mPa·s且与大庆原油界面张力最低值2.4×10-2 mN/m的含质量分数为0.18%HPAM、0.1%SDOLC、0.15%NaOH和0.06%HEDP·Na4体系作为Gemini型表面活性剂三元复合驱油体系。注入0.6PV该体系在均质岩心中水驱基础上可提高采收率26.11%,在非均质岩心中水驱基础上可提高采收率22.25%。     

甜菜碱与胜利原油间界面张力的影响因素

采用旋转滴法测定了两性离子表面活性剂十六烷基二乙基羟丙基磺基甜菜碱与胜利原油间界面张力,并考察了矿化度、二价离子浓度及弱碱NaHCO3对界面张力的影响。结果表明,甜菜碱分子与原油活性组分在界面上混合吸附、协同作用,共同决定油水界面张力。电中性的甜菜碱表面活性剂在界面上排列较为紧密,随着离子半径较小的Na＋和Mg2＋质量分数增大,界面张力呈缓慢下降的趋势;而随着离子半径较大的Ca2＋质量分数增大,界面张力始终较高;NaHCO3与原油活性组分反应,能将油水界面张力降至超低,此时总矿化度起决定作用,离子类型影响不大。     

混凝土集料-浆体界面过渡区微观结构表征技术综述

硬化混凝土由集料、界面过渡区和水泥浆体三个部分组成。其中集料一浆体界面过渡区被认为是混凝土中最薄弱的环节。界面的表征手段对界面研究极其重要,在理解界面的性质、特征等方面起到了很大的作用;界面问题研究的深入,与研究方法的不断更新有密切关系。本文归纳了界面过渡区微观结构特征,并在此基础上结合界面过渡区微观结构具体的研究对象,对表征ITZ的试验技术进行了评述,指出界面研究的一些潜在的方法。     

Refill Friction Stir Spot Welding Al Alloy to Copper via Pure Metallurgical Joining Mechanism

The current investigation of refill friction stir spot welding(refill FSSW) Al alloy to copper primarily involved plunging the tool into bottom copper sheet to achieve both metallurgical and mechanical interfacial bonding. Compared to conventional FSSW and pinless FSSW, weld strength can be significantly improved by using this method. Nevertheless, tool wear is a critical issue during refill FSSW. In this study, defect-free Al/copper dissimilar welds were successfully fabricated using refill FSSW by only plunging the tool into top Al alloy sheet. Overall, two types of continuous and ultra-thin intermetallic compounds(IMCs) layers were identified at the whole Al/copper interface. Also, strong evidence of melting and resolidification was observed in the localized region. The peak temperature obtained at the center of Al/copper interface was 591℃, and the heating rate reached up to 916 ℃/s during the sleeve penetration phase. A softened weld region was produced via refill FSSW process, the hardness profile exhibited a W-shaped appearance along middle thickness of top Al alloy. The weld lap shear load was insensitive to the welding condition, whose scatter was rather small. The fracture path exclusively propagated along the IMCs layer of Cu_9Al_4 under the external lap shear loadings, both CuAl_2 and Cu_9Al_4 were detected on the fractured surface on the copper side. This research indicated that acceptable weld strength can be achieved via pure metallurgical joining mechanism, which has significant potential for the industrial applications.     

聚丙烯基木塑复合材料的研究进展

概述了近年来国内外聚丙烯（PP）基木塑复合材料的研究概况，PP和木质材料的界面增容方法以及PP基木塑复合材料的基本性能；并展望了目前国内PP基木塑复合材料的研究方向。     

复合碱三元体系与含CO_2二类油层适应性研究

针对大庆北一区断东二类油层强碱三元复合驱现场试验,分析了试验区中心井伴生气中CO2含量的变化趋势以及和三元液的化学作用规律,研究了氢氧化钠和碳酸钠复配三元体系的界面张力、黏度特性、驱油效率。其中HPAM质量浓度2 000mg/L、重烷基苯磺酸盐质量分数0.3%、氢氧化钠质量分数0.8%、碳酸钠质量分数0.4%组成的复合碱三元体系(简称F21)综合性能较优。复合碱(F21)三元体系2h的平衡界面张力低至6.5×10-3mN/m;复合碱(F21)三元体系的黏度比强碱体系增加28.5%,且三元体系黏度随复合碱强度减弱而升高;复合碱(F21)三元体系比水驱采收率提高24.4%,和强碱体系化学驱采收率接近;非均质模型化学驱采收率比均质模型降低2.4%。     

Interface Structure and Formation Mechanism of Directly-Bonded Joints of Silicated Graphite to Fe-based Alloys

Commercially available 000Cr3OMo2 ferritic stainless steel and 4J33 ferromagnetic expansion alloy were di- rectly bonded to silicated graphite at 1180-1200℃ and 1100-1150℃, respectively, Intedacial microstructures were examined by scanning electron microscopy, electron probe microanalysis, and X-ray diffraction. The results showed that transient liquid-phase present during bonding promoted the interracial reactions during bonding. Plenty of brittle chromium carbides, such as （Cr, Fe）7C3 and （Cr2.5Fe4.3Mo0.1）C3, were observed in 000Cr3OMo2/silicated graphite joints. Besides, transverse cracks were also found. In case of 4J33/silicated graphite system, well bonded joints free of defects Were obtained.