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C15H14F3NO3, monoclinic, P21 (no. 4), a = 5.0637(5) Å, b = 19.1061(19) Å, c = 7.4883(6) Å, β = 95.666(9)°, V = 720.94(12) Å3, Z = 2, Rgt(F) = 0.0463, wRref(F2) = 0.1036, T = 294.8(6) K.

C15H14F3NO3, monoclinic, P21 (no. 4), a = 5.0637(5) Å, b = 19.1061(19) Å, c = 7.4883(6) Å, β = 95.666(9)°, V = 720.94(12) Å3, Z = 2, Rgt(F) = 0.0463, wRref(F2) = 0.1036, T = 294.8(6) K. [ABSTRACT FROM AUTHOR]

In view of the frequent occurrence of marine accidents and the complex interaction of various risk-influencing factors (RIFs), a data-driven method to risk analysis that combines association rule mining (ARM) and complex network (CN) analysis is proposed in this study. The efficient FP-Growth algorithm is applied to facilitate ARM to examine risk patterns that frequently occur in marine accidents. Subsequently, CN theory is employed to scrutinise the multifaceted role of various RIFs and their interactions in the complex marine accident system, which involves the basic characteristics of the network, the identification of key RIFs through the application of the weighted LeaderRank (WLR) algorithm, and a robustness analysis. The results of the study indicate that compared with random networks, marine accident networks exhibit a higher level of complexity, which brings challenges to safety prevention and control. Inadequate regulation, violations, and deficiencies in safety management systems are identified as key RIFs, stressing the urgency of improving supervision, strengthening law enforcement and strengthening the safety management system. This study may facilitate maritime safety management of maritime traffic and the development of risk analysis methods. [ABSTRACT FROM AUTHOR]

Oil-based foam has become a research hotspot in petroleum industry, whose stability plays a key role in the application. The employment of oil-based foam prevents the damage to water-sensitive reservoir. This paper focuses on the stabilization of oil-based foam by improving the viscoelasticity of foam film and the effect study of polymer-surfactant. The Polydimethylsiloxane (PDMS) and Natural rubber (NR) are employed to stabilize oil-based foam, and the comprehensive properties of foam which created by air flow method are evaluated by FCI. Besides, the behavior of interfacial adsorption foam film is analyzed through rheological study and molecular dynamics (MD) simulation. According to the results, the oil-based foam volume increases to 150 mL and the half-life time is extended to 140 s with the combination of NR and PDMS. It is ascribed that the synergistic effect of NR and PDMS molecules. The NR molecules, which are stretched and crimped corresponding to the change of external force, begin to move toward the interface after blending with PDMS to improve the viscoelasticity of the foam film. [ABSTRACT FROM AUTHOR]

Oil-based foam stabilized by dispersed asphaltene is potential in the oil recovery process of water-sensitive formations. But asphaltenes are prone to aggregate, which jeopardizes the stability of the foam. This paper investigated the effect of different VO79 (model asphaltene compound violanthrone-79) systems on the performance of oil-based foams through surface tension and foaming tests. And simulations were performed to investigate the microscopic mechanism of ODA (octadecyl amine) and Span20 (sorbitan monolaurate) on the dispersion effect of VO79 and the effect of their mixtures on the interfacial film formation. The experimental results showed that the mixed system of ODA, Span20, and VO79 significantly enhances the performance of the oil-based foam. According to simulative results, ODA and Span20 blending are able to form ODA: Span20 molecular pairs, inhibiting the aggregation of model asphaltenes. The blend of ODA, Span20, and VO79 tends to form a ternary supramolecular complex, assembling into a dense and stretchable interfacial film. The synergistic effect generated by the ternary blends is capable of optimizing the performance of oil-based foams. [ABSTRACT FROM AUTHOR]