In recent years, graphene oxide(GO), prepared by the modified Hummers’ method, and its derivatives have become a focus of research owing to their outstanding physical and chemical properties and low cost. Drawing ins...In recent years, graphene oxide(GO), prepared by the modified Hummers’ method, and its derivatives have become a focus of research owing to their outstanding physical and chemical properties and low cost. Drawing inspiration from the mussel protein,a facile and environmentally-friendly method was employed to fabricate superhydrophobic/superoleophilic reduced graphene oxide(rGO) derivative. The preparation comprises two steps: coating GO nanosheets with polydopamine(PDA) and subsequent reaction with 1H,1H,2H,2H-perfluorodecanethiol. Due to the excellent adhesive ability of PDA, the resulting f PDA modified rGO nanosheets(rGO-f PDA) were firmly immobilized onto polyurethane(PU) sponge skeleton by a simple drop-coating method. The as-prepared rGO-f PDA functionalized sponge exhibited superhydrophobic behavior with a water contact angle of 162°±2°, high organic adsorption capacity, recyclability and stable oil/water separation behavior under different acidic/alkaline conditions. Due to its facile fabrication technique and outstanding properties, the superhydrophobic-superoleophilic PU-rGOf PDA sponge holds great promise as an oil adsorbent for cleaning up large-scale pollution of oil and organic solvents, and dehydrating crude oil.展开更多
采用搅拌铸造法制备了漂珠/镁合金复合材料可溶压裂球。基于正交实验法,分析合金元素含量对复合材料溶解速率和抗压强度的影响。采用扫描电子显微镜(SEM)和X射线衍射仪(XRD)分析复合材料的微观组织和物相组成。通过浸泡实验和准静态压...采用搅拌铸造法制备了漂珠/镁合金复合材料可溶压裂球。基于正交实验法,分析合金元素含量对复合材料溶解速率和抗压强度的影响。采用扫描电子显微镜(SEM)和X射线衍射仪(XRD)分析复合材料的微观组织和物相组成。通过浸泡实验和准静态压缩实验评价复合材料的溶解性能和力学性能,并通过扫描电子显微镜分析复合材料溶解后微观形貌和断口形貌,从而得到复合材料的溶解机理和断裂机制。实验结果表明,影响漂珠/镁合金复合材料溶解速率的合金元素的主次顺序为:Al>Zn>Ni>Cu,最优合金成分为:Al 15%, Zn 6%, Cu 1.5%, Ni 1%(质量分数)。漂珠/镁合金复合材料中除了α-Mg、漂珠和β-Mg17Al12外,还存在Mg2Si和MgO相。复合材料的最大溶解速率为11.96 mg·h^-1·cm^-2,抗压强度为352 MPa,相比于镁合金分别提高了93.5%和9.7%。溶解速率提高的主要原因是复合材料中分布着较多的漂珠和Mg2Si等相,与α-Mg形成腐蚀原电池,加速复合材料的溶解。抗压强度提高的主要原因是细晶强化、第二相强化和位错强化的共同作用。展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.51701240&41206063)Key Research and Development Program of Shandong Province(Grant No.2017GGX20123)Fundamental Research Funds for the Central Universities(Grant Nos.19CX05001A,16CX05011A&17CX02063)
文摘In recent years, graphene oxide(GO), prepared by the modified Hummers’ method, and its derivatives have become a focus of research owing to their outstanding physical and chemical properties and low cost. Drawing inspiration from the mussel protein,a facile and environmentally-friendly method was employed to fabricate superhydrophobic/superoleophilic reduced graphene oxide(rGO) derivative. The preparation comprises two steps: coating GO nanosheets with polydopamine(PDA) and subsequent reaction with 1H,1H,2H,2H-perfluorodecanethiol. Due to the excellent adhesive ability of PDA, the resulting f PDA modified rGO nanosheets(rGO-f PDA) were firmly immobilized onto polyurethane(PU) sponge skeleton by a simple drop-coating method. The as-prepared rGO-f PDA functionalized sponge exhibited superhydrophobic behavior with a water contact angle of 162°±2°, high organic adsorption capacity, recyclability and stable oil/water separation behavior under different acidic/alkaline conditions. Due to its facile fabrication technique and outstanding properties, the superhydrophobic-superoleophilic PU-rGOf PDA sponge holds great promise as an oil adsorbent for cleaning up large-scale pollution of oil and organic solvents, and dehydrating crude oil.
文摘采用搅拌铸造法制备了漂珠/镁合金复合材料可溶压裂球。基于正交实验法,分析合金元素含量对复合材料溶解速率和抗压强度的影响。采用扫描电子显微镜(SEM)和X射线衍射仪(XRD)分析复合材料的微观组织和物相组成。通过浸泡实验和准静态压缩实验评价复合材料的溶解性能和力学性能,并通过扫描电子显微镜分析复合材料溶解后微观形貌和断口形貌,从而得到复合材料的溶解机理和断裂机制。实验结果表明,影响漂珠/镁合金复合材料溶解速率的合金元素的主次顺序为:Al>Zn>Ni>Cu,最优合金成分为:Al 15%, Zn 6%, Cu 1.5%, Ni 1%(质量分数)。漂珠/镁合金复合材料中除了α-Mg、漂珠和β-Mg17Al12外,还存在Mg2Si和MgO相。复合材料的最大溶解速率为11.96 mg·h^-1·cm^-2,抗压强度为352 MPa,相比于镁合金分别提高了93.5%和9.7%。溶解速率提高的主要原因是复合材料中分布着较多的漂珠和Mg2Si等相,与α-Mg形成腐蚀原电池,加速复合材料的溶解。抗压强度提高的主要原因是细晶强化、第二相强化和位错强化的共同作用。
