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Injection of bubbly jets is a critical process in various fields, such as fuel atomization and petrochemicals. However, existing instability models for bubbly jets have predominantly focused on density variations due to bubble compressibility, largely neglecting the impact of bubbles on the macroscopic rheological properties of the mixture. In this study, we have integrated compressibility with non-Newtonian properties induced by bubbles to explore the evaluation of jet perturbations. Additionally, considering bubble pre-deformation before injection, we particularly examine the role of unrelaxed axial elastic tension in the bubbly jets. Both linear stability analysis and energy budget methods are used to illustrate the contributions of viscosity, elasticity, and compressibility. The results indicate that the viscoelastic effects induced by bubbles can significantly outweigh the effects of compressibility during the jet destabilization process. Notably, a slight unrelaxed tension can markedly increase both the perturbation growth rate and the cutoff wavenumber, potentially making it a more dominant driver of jet instability than the classical surface tension. [ABSTRACT FROM AUTHOR]

In this paper, we study a stochastic differential investment consumption and proportional reinsurance game problem for two competitive insurers with constant absolute risk aversion (CARA) utilities. The utility of an insurer depends not only on his absolute wealth and consumption but also his relative wealth and consumption when compared to the other insurer. The surplus processes of both insurers are governed by the diffusion approximated process of the classical Cramér-Lundberg model. Each insurer is allowed to purchase a proportional reinsurance treaty and invest his surplus into a financial market consisting of one risk-free asset and one risky asset to manage his insurance risk. Moreover, the consumption behavior of each insurer is also considered. The main objective of each insurer is to maximize the utility of his terminal surplus and accumulated consumption relative to that of his competitor. Applying the techniques of stochastic dynamic programming, we obtain the Hamilton-Jacobi-Bellman (HJB) equations for both insurers. We establish the equilibrium reinsurance-investment-consumption strategies and the corresponding equilibrium value functions of both insurers by solving the HJB equations. Finally, we perform some numerical examples to illustrate the influence of model parameters on the equilibrium reinsurance-investment-consumption strategies. Numerical simulation results indicate that the insurer's investment, consumption and reinsurance strategies increase with the increasing of the sensitivity parameter to competition; and decrease with the increasing of the constant absolute risk aversion coefficient. [ABSTRACT FROM AUTHOR]

We apply the complex method to build new exact solutions for the conformable Huxley equation. The results show that abundant new exact solutions were constructed, which extends the results of Cevikel, Bekir and Zahran. Further, we extend the undetermined form for the exponential function solutions in the complex method. [ABSTRACT FROM AUTHOR]

Complex microbiological interactions in reinjection water can lead to severe corrosion of pipelines. In this study, X65 specimen was used for corrosion simulation experiments to explore the microbiologically influenced corrosion (MIC) and mechanism in actual oilfield reinjection water. The results of scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) showed that the X65 carbon steel was severely corroded by microorganisms, with the maximum localized corrosion pit depth of 15.04 μm after 28 days of immersion. Electrochemical analysis and weight loss measurement further confirmed that the mixed microorganisms caused serious corrosion of X65 carbon steel, and the maximum corrosion rate was 0.249 mm/y. Furthermore, microbial community structure determination showed that mixed microorganisms in the actual reinjection water formed a corrosive biofilm on the surface of X65 steel, inducing severe pitting corrosion, which was mainly attributed to the synergistic effect of Pseudomonas , sulfur-oxidizing bacteria (SOB), sulfate-reducing bacteria (SRB) and methanogenic archaea. The results of this study have important guiding significance for the identification of MIC process for actual water samples of the oilfield and the timely adjustment of MIC control measures. [Display omitted] • Actual reinjection water samples from offshore platforms were used for corrosion simulation experiments. • Corrosive microorganisms synergistically promote corrosion of X65 carbon steel. • The microbial community structure of biofilm/corrosion product layer changed with time. • Identifying microorganisms in the corrosion process facilitates the development and adaptation of MIC prevention strategies. [ABSTRACT FROM AUTHOR]

Microbiologically induced corrosion (MIC) is widespread in the oilfield industry, and new environmentally friendly materials are urgently needed to inhibit MIC with the increasing environmental requirements and microbial resistance problems. The synthesis method and cost of the materials are important factors that must be considered in the production and application. In this study, Ag/Cu bimetallic nanoparticles (BNPs) were synthesized by eco-friendly and sustainable method using waste banana peel extract (BPE) as a green reducing. The antibacterial and corrosion inhibition properties of Ag/Cu BNPs were investigated by using the enriched mixed strains containing sulfate-reducing bacteria (SRB) as model bacteria. The results of electron microscopy showed that the prepared BNPs exhibited spherical structure with about 19.0 nm in size. The synthesized nanoparticles significantly inhibited the growth of mixed strains by antimicrobial experiments with minimum inhibitory concentration (MIC) value of 9.38 μg/mL. The addition of Ag/Cu BNPs (9.38 μg/mL) inhibited the corrosion of X65 carbon steel induced by the mixed strains with 77.9% compared to the untreated condition. Correspondingly, the number of sessile SRB cells in the solution containing Ag/Cu BNPs (9.38 μg/mL) after 28 days of immersion decreased by 5-log compared with the treatment group without nanomaterials (1.1 × 10 8  cells/cm 2 ). Furthermore, the observation of the surface morphology and strains cellular microstructure of carbon steel treated with nanoparticle materials illustrated that the corrosion inhibition mechanism mainly includes destroying cell structure, affecting metabolic activities and inhibiting biofilm formation. The environmentally friendly nanoparticle materials prepared in this study have great potential in the safe and clean production of oil fields., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)