This study aims to explore the tensile and impact properties (tensile strength, modulus of elasticity, and impact strength) of polypropylene (PP)-based nanocomposites reinforced with graphene nanosheets, nanoclay, and basalt fibers. The response surface methodology (RSM) with Box–Behnken design (BBD) was adopted as the experimental design. An internal mixer was used to prepare compounds consisting of 0, 0.75 and 1.5 wt% graphene nanosheets, 0, 10 and 20 wt% basalt fibers, and 0, 3 and 6 wt% nanoclay. The samples were prepared by a hot press machine for mechanical testing. The tensile tests were run to determine the tensile strength, and modulus of elasticity, and the Charpy impact tests were performed to assess the impact strength. It was found that the addition of basalt increased the tensile strength, modulus of elasticity, and impact strength by 32%, 64% and 18%, respectively. Also, the incorporation of the low-weight graphene nanosheets increased the tensile and impact strength by 15% and 20%, respectively, Adding graphene nanosheets generally improved the modulus of elasticity by 66%. Similarly, the addition of nanoclay improved the tensile strength by 17% and increased the modulus of elasticity by 59%, but further addition of it decreased the impact strength by 19%. The values obtained by this experiment for the mechanical property were roughly close to the data yielded from desirability optimization.

To examine the acousto-structural behavior of a sandwich cylindrical shell benefiting from hexagonal honeycomb structures in its core and functionally graded porous (FGP) layers on its outer and inner surfaces, a comprehensive study based on an analytical model which also considers the effect of an external flow is conducted. A homogenous orthotropic model is used for the honeycomb core while its corresponding material features are found from the modified Gibson’s equation. The distribution pattern of FGP parts is either even or logarithmic-uneven, and a special rule-of-mixture relation governs their properties. Based on the first-order shear deformation theory (FSDT), Hamilton’s principle is exploited to derive the final coupled vibro-acoustic equations, which are then solved analytically to allow us to calculate the amount of sound transmission loss (STL) through the whole structure. This acoustic property is further investigated in the frequency domain by changing a set of parameters, i.e., Mach number, wave approach angle, structure’s radius, volume fraction, index of functionally graded material (FGM), and different honeycomb properties. Overall, good agreement is observed between the result of the present study and previous findings.

The idea of transferring vital drugs through nanotubes in the human body has attracted the attention of many researchers in the field of nanomedicine. Accordingly, the main objective of this article is to investigate the forced vibration response of two hybrid smart carbon nanotubes connected using springs and conveying a nanofluid, with each one including either a piezoelectric or electrorheological fluid layer. To this aim, a slip boundary condition along with a Knudsen number is employed to address the vibration behavior of smart hybrid sandwich nanotubes acted upon by a moving sinusoidal load, while equations are derived with the aid of the Timoshenko beam model and nonlocal strain gradient theory. The former theory is complemented with hardening and softening material effects which can greatly enhance the precision of the results. Furthermore, Hamilton’s principle is implemented to obtain the equations of motion. Regarding the time response of the structure, a combination of modal analysis and the Laplace transform is applied. The accuracy of the developed procedure is verified through a set of comparisons of static deflection (as a result of a point load) and vibration frequencies. In addition, the impact of a number of parameters ranging from nanoparticle velocity to material length scale is investigated.