Most pumping actions entail a physical volume change of the duct, which is frequently achieved by having a compliant wall or membrane. To the best of our knowledge, the current study is the first report on a mathematical model developed to analyze the peristaltic transport of a Newtonian fluid in a curved duct with rectangular face and compliant walls. Such geometries are most commonly used in clinical and biological equipment, where the walls of the duct need to be flexible. Flexible ducts are more useful than rigid ones because they do not require any extra modifications or accessories. Here, we have used the conditions of lubrication theory to construct an accurate model, and a common perturbation technique was incorporated to handle the Navier-Stokes equations with emphasis on various aspect ratios and curvatures. A system of curvilinear coordinates operating according to the principles of the cylindrical system was employed to represent the mathematical problem. No-slip boundary limitations were considered at the walls along with the extra constraint of compliant walls showing damping force and stiffness. Comprehensive graphical representations were made to illustrate the effects of all emerging factors of the study in both two- and three-dimensional formats. We found that large curvatures and flexure rigidity decreased the fluid velocity uniformly, but the aspect ratio and amplitude parameters could promote fluid velocity. Validation of the results was performed through the generation of a residual error curve. The current readings were taken again with a straight duct to make a comparison with the existing literature.

In this paper, a synthesized zeolite (ZSM-5) is used as an adsorbent to analyze the adsorption phenomenon of carbon dioxide. This investigation, based on the statistical physics treatment, applied the multilayer model with saturation to understand the CO2 adsorption on four samples, namely M-ZSM-5 (M = Na+, Mg2+, Zn2+, La3+), at various temperatures T = 0 °C, 30 °C and 60 °C. The modeling results indicated that CO2 adsorption occurred via a non-parallel orientation on the ZSM-5 surface. The CO2 adsorption capacities varied from 26.14 to 28.65 cm3/g for Na-ZSM-5, from 25.82 to 27.97 cm3/g for Mg-ZSM-5, from 54.82 to 68.63 cm3/g for La-ZSM-5 and from 56.53 to 74.72 cm3/g for Zn-ZSM-5. Thus, Zn-ZSM-5 exhibits the highest adsorption amount. The analysis of the adsorption energies shows that the adsorption of CO2 on ZSM-5 zeolite is a physisorption phenomenon that could be controlled thanks to the energy parameters obtained via the numerical findings using the multilayer statistical model. Finally, the distribution of site energy was determined to confirm the physical character of the interactions between adsorbate/adsorbent and the heterogeneity of the zeolite surface.

Vaccination against any infectious disease is considered to be an effective way of controlling it. This paper studies a fractional order model with vaccine efficacy and waning immunity. We present the model’s dynamics under vaccine efficacy, the impact of immunization, and the waning of the vaccine on coronavirus infection disease. We analyze the model under their equilibrium points. The model under the equilibrium points is discussed and proven that it is locally asymptotically stable if Rv is lesser than unity. We present the backward bifurcation hypothesis of the model and show that there is a parameter β2 that causes the backward bifurcation in the imperfect vaccine model. We show certain assumptions when ψ=1 for the imperfect vaccine case; the model is both stable globally asymptotically at the disease-free (R0≤1) and endemic cases (R0>1). By using infected cases from the recent wave throughout Pakistan, we shall estimate the model parameters and calculate the numerical value of the basic reproductive number R0≈1.2591. We present the comprehensive graphical results for the realistic parameter values and show many useful suggestions regarding the elimination of the infection from society. The vaccination efficacy that provides an important role in disease elimination is discussed in detail.

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