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排序方式: 共有683条查询结果,搜索用时 46 毫秒
21.
《Arabian Journal of Chemistry》2022,15(11):104286
Studies show that after acidizing operation of oil wells using the alkali/surfactant/polymer (ASP) flooding technology, the produced fluid is emulsified. Since the produced emulsion is stable, it affects the oil–water separation performance. In order to analyze the generation of stable emulsion in the produced fluid after acidizing an oil well, innovative separation experiments were carried out on real oil wells. During the experiments, solid particles in the middle layer of the emulsifying system in the produced fluid after acidizing ASP flooding were extracted and characterized. The generation of the stable emulsifying system in the produced fluid was studied through stability experiments and molecular dynamics simulations. The results showed that the synergistic effect of ferrous sulfide nanoparticles and surfactants was the fundamental reason for the strong emulsifying stability of the produced liquid after acidizing of the ternary composite system. The generation of ferrous sulfide solid particles mainly included two steps. First, sulfate reducing bacteria in injected water by ASP flooding reacted with sulfate in formation water to form hydrogen sulfide. Then, the hydrogen sulfide reacted with iron metal in oil wells and casing of wellbore to form ferrous sulfide particles. It was found that surfactants are adsorbed on the surface of ferrous sulfide nanoparticles. Subsequently, the control ability of surfactant on oil and water phases in the liquid film was enhanced. The performed analyses demonstrate that the adsorption of solid particles to the oil phase was enhanced, while the free motion of molecules in the oil phase at the liquid film position was weakened. The strength of the interfacial film between oil and water was further increased by the synergistic effect of ferrous sulfide nanoparticles and surfactant. The present study is expected to provide a guideline for a better understanding of the efficient treatment of produced fluids in ASP flooding. 相似文献
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Ultralight flexible polymers enable promising application in many fields but are often hindered by low reusability with fatigue failure, weak mechanical stability and low temperature resistance. Here, superelastic polyimide nanofiber aerogels (PNFAs) with high hydrophobicity have been prepared by utilizing the polyamic acid (PAA) nanofibers to construct a continuous and isotropic fibrous architecture. “Fiber-bonding” effect is designed to endow the PNFAs with the structure-derived superelasticity. The results demonstrate that the PNFAs possess ultralight densities (9.7–19.1 mg cm−3), excellent absorption capacity (58 times for n-hexane), broad working-temperature range, high resilience after 1000 fatigue cycles at 60% strain, and outstanding thermal insulation performance. Analysis of 50 absorption-harvesting cycle tests reveals that these highly hydrophobic PNFAs possess an ultrahigh reusability. The compressed PNFAs return to their original shape after they are distilled to recover the absorbed pollutants. These PNFAs with high absorption capacity and robust mechanical stability are promising to be applied in a variety of industrial and environmental applications. 相似文献
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In this study, Polystyrene based materials, PS, with tailored morphologies are prepared by solution blow spinning, SBS. It is demonstrated that this tailored morphology of PS can be designed through the choice of particular SBS processing conditions. Several SBS processing conditions, including solution concentration, gas pressure and solution feeding rate are changed to consider their individual and combined effects on the final polymer morphology. The morphology of the PS samples is inspected by scanning electron microscopy, SEM. This morphology is analyzed in terms of fiber diameter and relative amount of fibers respect to other morphological features such as lumps or fibers aggregates. Coupling the experimental analysis with the use of Box-Behnken method and the desirability function, particular values of parameters controlling the SBS processing conditions are able to be obtained in order to achieve certain morphologies of PS, in particular, maximum amount of fibers with the minimum diameter. Influence of PS morphology on hydrophobicity and the ability of oil absorption is studied by contact angle measurements. The use of Box-Behnken design together with the desirability function is revealed as a reliable and accurate method for designing polystyrene materials through the optimal election of SBS processing conditions for the production of the polymer with particular morphologies and therefore, with especial performance regarding adsorption and absorption of liquid wastes. SBS PS constituted by the maximum amount of fibers with the shortest diameters lead to superhydrophobic materials with the highest ability of oil absorption for the PS. 相似文献
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《Current Applied Physics》2020,20(2):344-351
Oil spills are a major threat to the marine ecosystem, requiring immediate solutions to remove spilled oil from oceanic environments. In this study, we report a superhydrophobic molybdenum disulfide (MoS2) coated polydimethylsiloxane (PDMS) sponge and demonstrate its high proficiency in spilled oil recovery and oil spill detection based on oil-water separation ability. This novel oil sorbent is fabricated by a simple dip-coating to incorporate MoS2 flakes into PDMS sponge. The optimized MoS2-sponge displays a water contact angle of >152°, demonstrating excellent superhydrophobicity and high oil absorption (>97 wt%) for a variety of oils, including vegetable oil and fuel waste. Moreover, the material retains excellent oil absorption capability upon repetitive compression cycles. The versatility of this novel sorbent has been extended for the real-time spontaneous detection of oils by taking advantage of electrically conductive MoS2 layers. 相似文献
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近红外(NIRS)技术分析小样品油菜籽芥酸和含油量的应用研究 总被引:4,自引:0,他引:4
以完整油菜籽为样品,采用旋转杯和安培瓶两种样品杯、每种样品分为4×2种不同样品量并通过不同光谱预处理来优化油菜籽芥酸和含油量的近红外分析模型。结果表明:油菜籽各小样品含油量模型的决定系数(R2)从93.93%到96.93%不等,均方差(RMSECV)从0.56到0.79不等;油菜籽各小样品芥酸模型的决定系数(R2)从96.91%到98.42%不等,均方差(RMSECV)从1.73到2.43不等。随着样品量的逐渐增加,油菜籽芥酸和含油量不同样品杯模型各参数逐渐有所优化;同一样品厚度时,油菜小样品芥酸和含油量的旋转样品杯模型各参数均略优于安培瓶样品模型;不同样品量的NIRS模型,W3和W4差异不大,依次优于W2和W1。最小样品量AW1为0.3g。优化油菜小样品模型时,应该选择全部的预处理方法,根据优化结果选择最佳模型。外部检验结果表明:不同重量小样品(W1/0.3g、W2/1.0g、W3/2.0g和W4/4.0g)模型之间及其与标准化学值之间在0.01水平上差异不显著,说明W1和W2小样品模型同样可应用于油菜品质育种材料的分析选择。 相似文献
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以天然石墨为原料,用Hummers法和超声剥离法制备了氧化石墨烯(GO).将氧化石墨烯浸渍,涂覆于三聚氰胺海绵表面,在线还原制得还原氧化石墨烯基三聚氰胺海绵(RGOME).通过扫描电子显微镜(SEM)、傅里叶变换红外光谱(FTIR)仪及光学接触角测定仪等分析了RGOME的结构,考察了RGOME对多种油品的吸附性能,并对其油水选择吸附性能和循环使用性能进行了研究.结果表明,RGOME具有疏水超亲油性,对油品的吸附量达到56~127 g/g,可用Bangham方程描述RGOME对甲苯和煤油的吸附动力学过程;在选择吸附过程中,油品浓度急剧降低,吸附量不断升高,分离效率达到74.49%,可较好地实现油水分离;吸附油品的RGOME经脱附可多次循环使用. 相似文献
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