Hediye Deniz Ada

Parsley (Petroselinum crispum) leaves are rich in phenolic acids, flavonoids, and volatile compounds with antioxidant activity, but these bioactives degrade rapidly after extraction. Here, aqueous parsley leaf extract (PLE) was incorporated into electrospun polyvinyl alcohol (PVA) nanofibers and characterized by SEM, ATR-FTIR, XRD, thermogravimetric analysis (TGA), and the DPPH radical scavenging assay. SEM showed continuous submicron fibers under the conditions tested (17 kV, 18 cm, 0.3 mL/h), with a mean diameter of 333.7 ± 94.0 nm (N = 40, measured across two separate micrographs). ATR-FTIR showed that PVA and PLE bands were both present in the composite spectrum, with an O–H stretching shift consistent with possible hydrogen-bonding interactions. XRD showed that the main PVA reflection persisted after electrospinning, with a lower raw peak intensity after PLE addition, suggestive of partial interaction with the polymer chains. TGA showed that the main decomposition temperature of the PLE/PVA nanofiber (277 °C) fell between those of PVA (266 °C) and PLE (296 °C), consistent with PLE incorporation within the PVA matrix. In the DPPH assay (n = 3), pure PLE showed a radical scavenging activity of 96.61 ± 0.29% and the PLE/PVA nanofiber 89.32 ± 0.27%, indicating measurable antioxidant activity of the composite fibers; because the samples were not normalized to an equivalent extract dose and no PVA-only control was included, the activity retained after electrospinning is not quantified. These preliminary results show that aqueous parsley extract can be incorporated into PVA nanofibers with retention of fibrous morphology. Unlike a recently reported multicomponent PVA/metal–organic-framework system containing parsley extract for wound healing, this work addresses a simple, organic-solvent-free binary PLE/PVA system and its basic physicochemical characteristics; it does not claim a performance advantage over that or other plant extract-loaded PVA systems, and release, antimicrobial, and application-specific tests were not part of this study.

Erosion corrosion is encountered in many areas of industry and is a very complex phenomenon. In this study, it is aimed to investigate the effects of erosion corrosion in elbow pipes with different shear moduli, velocities of fluid, density of pipe using Ansys Workbench Explicit Dynamics module which is computer-aided and based on finite element. Statistical analyses were also performed to obtain the best flow parameters. SolidWorks program was used for three-dimensional studies considering elbow pipe design. The fluid properties and physical conditions were applied to the three-dimensional solid model in the pipe flow analysis. At the end of the dynamic analysis, erosion values (deformation) occurring in the elbow pipes were statistically compared to each other.

In this study, the reason for erosion-corrosion of drinking or mains water in the faucet was investigated by computational fluid dynamics. Pipes used in homes, the service sector, and industry are responsible for transporting different types of fluids from one place to another. Considering the faucet design, the SolidWorks program was used for 3D studies. In-faucet flow analyses were performed using Ansys Fluent, a computational fluid dynamics program based on the finite volume method. In the analyses, lime particles were chosen. At the end of the analysis, the amount of erosion in the faucet was obtained.

Viruses are the leading infectious diseases. Viruses spread very fast and has a mortal risk to people with chronic diseases. Different methods are being sought to protect against the virus. In this study, the effect of face mask used against Covid-19 and other infections were investigated using finite element analysis. The effects of droplets formed because of cough or sneezing on the masked and without masked human model were analyzed. The human model without mask has a negative effective on the human face. The risk of infection is higher on the unmasked human model than on the masked human model.