浸润性可调的导电聚苯胺/聚丙烯腈同轴纳米纤维

聚苯胺(PANI)因其具有可调的导电性、优异的化学稳定性、简单的制备方法等特点, 在化学电源、抗静电涂层、电磁屏蔽材料、抗腐蚀、传感器等领域具有广泛的应用前景[^1~4]. 由于聚苯胺的刚性分子链使得聚苯胺几乎不溶不熔, 难以加工应用, 因此, 将导电聚合物直接制成纳米纤维一直是合成纤维界所希望的目标之一. 此外, 由于材料尺度的减小, 使纳米材料的表面与界面性质,尤其是表面浸润性变得更为突出.浸润性是固体表面的重要特征之一, 它主要由表面的化学组成和微观结构共同决定^[5,6]. 可调的浸润性在超疏水材料、药物传输、仿生材料和微流体等领域具有重要的应用价值^[7~10] , 引起人们广泛关注.     

Using magnesium oxide nanoparticles in a magnetic field to enhance oil production from oil-wet carbonate reservoirs

Enhanced oil production can maximise yield from depleted reservoirs, and in the face of dwindling global oil reserves can reduce the need for exploratory drilling during the transition away from fossil fuels. A hybrid technique, merging a magnetic field (MF) and magnesium oxide (MgO) nanoparticles (NPs), was investigated as a potential method of enhancing oil production from oil-wet carbonate reservoirs. The impact of this hybrid technique on rock wettability, zeta potential, and interfacial tension was also investigated. Displacement experiments were carried out on oil-wet Austin chalk – a laboratory carbonate rock analogue – using MgO NPs in deionized water (DW) and salt water (SW), in the presence of an MF up to 6000 G in strength. It was found that the addition of MgO NPs to DW before the spontaneous imbibition of the solution into initially oil-wet rock samples increased the recovery factor (RF, defined as the volume of oil recovered divided by the initial oil in place). For 0.005 wt% and 0.0025 wt% MgO NPs mixed in DW, the RF was 12.5% and 15.9% respectively. When DW was replaced with SW as the imbibing fluid, the RF increased by a further 0.7% of initial oil in place for the 0.0025 wt% MgO NPs. This additional increase in oil recovery was attributed to the presence of potential determining ions, which made the rock more water-wet. To avoid pore-clogging and thus the limited ingress of the solution into the rock, the NPs’ concentration was kept low. This hybrid technique is a cleaner alternative to conventional enhanced oil recovery techniques and will enable oil industries to produce oil more efficiently from existing reservoirs: when used in conjunction with Carbon Capture and Storage (CCS), this provides a useful short to medium-term option to support energy production during the transition to net zero.