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The transportation of liquids through pipelines is attributed with highenergy consumption due to the turbulent nature of their transportation. Low concentrations of polymeric additives were proven effective flow enhancing agent when injected into these pipelines due to its viscoelastic property capable of suppressing the turbulent structures; however, the mechanical degradation of polymers is a disadvantage, which can be controlled efficiently by using complex in a surfactant-polymer interface. In this presented work, turbulent drag reduction (DR) efficacy of anionic Xathan gum and nonionic surfactant (PDDAC) regarding the surfactant-polymer interface was studied using a rotating disk apparatus (RDA) technique and pipeline. The effect of surfactant addition, critical concentration of XG, and the dependence of drag reduction on the turbulent strength from the rotation speed were also studied. The critical behavior of the interface was found at XG (700 ppm) and (1000-ppm) concentrations, respectively. The drag reduction (~70%) was observed at critical concentration behavior, which is largely reliant on the alkyl chain in the surfactant molecule. The result of the a rotating disk apparatus (RDA) gave about 51% drag reduction with the Xanthan gum alone while in the pipe, about 58% drag reduction percent (DR%) was obtained. (PDDAC) alone yielded about 32% and 36% drag reduction in the rotating disk apparatus (RDA) and pipe respectively. However, combining the Xanthan gum polymer and Polydiallyldimethylammonium chloride (PDDAC) surfactant gave 62% drag reduction. Thus, it could be inferred that the combination of these duo has greater impact than the individual materials. It could thus be concluded that the complex formed by these materials is another form of drag reducing agents.

This paper focuses on the determination of the interaction between polymer (Polyacrylamide (PAM)) and surfactant (Sodium dod benzene sulfonate (SDBS)) as a drag reducer using Rotating Disk apparatus (RDA) at various concentrations (500, 700, 1000, 1500 and 2000) ppm individually and in the combined form under turbulent conditions at different rotation speed up to 3000 rpm, as well as studying their mechanisms as a drag reducer. The results show that the maximum percent drag reduction increases to (40, 41, 43, 45 and 48)% by using the combined additives of surfactant and polymer at the above concentrations respectively, with slower degradation and display drag reduction for a larger range of Reynolds numbers. The nano and micro particles formed from the combined PAA and SDBSA was studied using cryo-transmission electron microscopy (cryo-TEM) techniques. The images show the surrounding of polymer chain to the surfactant micelle to form an aggregate structure. A hexagonal crystalline form was suggested to describe the shape of the aggregate structure.

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Introduction: Acinetobacter baumannii (A.baumannii ) is a ubiquitous pathogen responsible for serious infections in hospitalized patients with a high propensity to develop resistance to antimicrobial agents. The study aimed to determine the antimicrobial resistance patterns and the prevalence of aminoglycoside resistance genes among A. baumannii clinical isolates from patients in different intensive care units (ICUs) in Alexandria, Egypt. Methods: A total of 100 A. baumannii isolates collected from ICU patients were confirmed as A. baumannii by VITEK 2 and the presence of the blaOXA-51 gene has been reported. Antimicrobial susceptibility testing was performed and Multiplex PCR was done for the detection of aminoglycoside resistance genes. Results: Most of the isolates (82%) were resistant to all tested aminoglycosides; resistance was higher for kanamycin and neomycin, followed by amikacin. The predominant AMEs were aphA6 and aphA1 in 86% and 67% of the isolates, respectively; aacA4 and aacC1 were detected in 37% and 8%, respectively, while aadA1 and aadB were present in 34% and 4%, respectively. Furthermore, armA gene was detected in 83% of the isolates. Conclusion: The results of this study revealed a high level carriage of armA and AMEs which limit the usage of aminoglycoside as a treatment option for A. baumannii and makes treatment extremely difficult.

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In the pipeline networks field, GAL surfactant can reduce drag forces relatively using a small quantity part per million (ppm). Accordingly, the drag reduction (DR) enhancement is highly recommended in many industrial applications specifically the crude oil transportation aspect. GAL solution was experimentally investigated at various concentrations. The experiments were performed at low concentrations range from 50 to 300 ppm, and high concentrations range from 1000 to 2000 ppm. The rotating disk apparatus (RDA) was used at various speeds range from 50 to 3000 rpm in all experiments. Torque values of the GAL solutions were compared with water alone. The results clearly show that the different concentrations of the Glycolic Acid Ethoxylate Lauryl Ether (GAL) are good drag reduction agents (DRAs), with clear and high torque reading differences. Further, GAL solutions have the same tendency at all concentrations. The torque finding was enhanced with increasing concentration.

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