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Lightweight materials with better resistance to sliding wear are prominent candidates for automobile brake drums, clutch pads and cylinder block applications to facilitate fuel economy. This attempt is reserved to cater to materials with higher tribological quality needs. Less dense foamy pumice stone particles were involved in three different percentages (5, 10, and 15 wt%) to reinforce lightweight AZ31 Mg alloy. A stir-assisted squeeze casting technique was pursued to process the composite and refine the grain structure. A phase detection, elemental mapping and microstructure study were done through X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and scanning electron microscopy (SEM), respectively. An experimental dry sliding wear scrutiny was administered using a pin-on-disc apparatus by considering: (i) ambient and elevated temperature environments and (ii) three different levels of loads. The results reveal a significant drop in wear loss and a frictional coefficient for 15% pumice-loaded composite than the base alloy. Post-wear examination acknowledges the fact that the ambient temperature wear is governed by adhesive-abrasive wear and high temperature is by abrasive wear mechanisms. Worn-out scrutiny authenticates the presence of oxide layers and their role in lubrication. A comparative study with previous works upholds the novel magnesium composite is the right candidate for the mentioned automobile applications.

The present investigation focuses on the microstructural behavior and mechanical properties of Aluminium alloy 2024 reinforced with SiC nanoparticles by applying the Friction Stir Processing (FSP) technique. Taguchi L9 orthogonal array was used to find the optimal process parameters. The experiment used the expected best process parameters, which confirmed the predicted highest value for the mechanical characteristic. Traverse speed, axial load, and rotating speed are the main factors affecting aluminum metal matrix composite. Hence, this experiment examined the effects of five different tool spinning speeds, specifically 800, 900, 1000, 1100, and 1200 rpm. Weld samples are fabricated wherein the stir zone contains SiC nanoparticles. The results of the study indicate that the optimal welding rotational speed of 1000 rpm has a significant impact on the microstructure, wear rate, and microhardness. Specifically, it was observed that the stirred zone exhibited enhanced wear resistance compared to other zones. The study's findings revealed that after implementing friction stir processing (FSP), a well-defined shear zone was observed on the advancing side of the stir zone. Additionally, it is found that the uniform dispersion and strong bonding of SiC particles with an aluminium matrix further enhance wear resistance.

In a variety of industries, including transportation, agriculture, and manufacturing, diesel engines are often employed. Due of rising prices and environmental concerns, researchers examined whether biodiesels might replace diesel. The current study looks into American Saffron Oil's feasibility as a feedstock for biodiesel production. The transesterification technique is used to extract American saffron oil methyl este(ASOME), which is then examined for its physical and chemical properties in accordance with ASTM standards. Diesel fuel and American Saffron Oil methyl ester are mixed on a volume basis to create a variety of fuel blends, including B20, B40, and B60. The test results showed that the 20 % ASOME mix had better performance and reduced emissions. Also, utilizing DIESEL-RK simulation software, diesel engine tests are conducted for the B20, B40, and B60 under identical operating circumstances. Moreover, diesel engine testing for the B20, B40, and B60 are carried out using DIESEL-RK simulation software under comparable operating circumstances. Results of simulation software tests show improved engine performance and reduced pollutants. When experimental data is compared to DIESEL-RK modeling software, it is found that brake thermal efficiency increased by 5.7 % and emissions of hydrocarbon and carbon monoxide decreased by 2.5 % and 14.3 %, respectively.

Background: Gynecological issues and sexually transmitted infections (STIs) pose significant challenges to women's health, particularly in developing nations. These challenges are exacerbated by limited access to modern reproductive healthcare facilities, economic constraints, and entrenched cultural norms. Consequently, most of the Pakistani population relies on traditional ethno-medicinal healthcare systems. This preference stems from the ease of access, affordability, widespread availability, and inherent trust placed in these alternative healthcare methods. Aim/objective: The inquiry aimed to report details on the application of conventional uses of plants in the health field in rural areas that could contribute to advancing the natural discovery of drugs. The objective of this analysis is to provide researchers with information on conventional and empirical knowledge of plant species concerning women's diseases. Methodology: Information on the common use of medicinal plants in treating women's diseases was gathered from electronic databases. As a keyword for the quest, ethnobotany, and ethnopharmacology were used together with gynecological complications. Result: The work of the current analysis has revealed that 217 plant species belonging to 89 families have been used in Pakistan's rural communities. The majority of plant species belong to the Apiaceae family, followed by the Asteraceae, Fabaceae, Solanaceae, Rosaceae, Lamiaceae, and other families. The biological interpretation of plants used in rural communities of Pakistan revealed that herbs and trees are the dominant forms with 58 % and 23 % respectively while shrubs and sub-shrubs with a low percentage of 17 % and 2 %. In natural preparation, leaves 29 %, flowers 22 %, seeds 14 %, fruits 14 %, roots 13 %, bark 7 %, and stems 5 % were the most used parts respectively and aerial parts, dried pericarp, bulb, bud, berry, latex, wood, rhizome, husk, fruit coat, oil, resins, twigs, and shoot were also used in minimum percentage. A multitude of plant species have found extensive application in the management of diverse women's health issues. These encompass concerns such as fatigue, mood fluctuations attributed to menstrual problems, gonorrhea, complications related to pregnancy, cravings for specific foods, throbbing breast pain, abdominal and pelvic cramps, excessive vaginal discharge, mastitis, irritability, abortion-related matters, headaches, uterine hemorrhage, Menorrhagia, Amenorrhea, Menopause, Vomiting Abortion, infertility and lactation challenges, as well as the regulation of lochia flow. Conclusion: This review provides remarkable information about the use of medicinal plants against women's diseases in the rural communities of Pakistan. It opens the gateway for the discovery of natural drug development.

Environmental sustainability concerns have led to exploring alternative fuels like biodiesel in transportation. However, biodiesel engines emit pollutants like NOx, CO, and PM, posing health and environmental risks. This review explores the use of Aluminium Oxide (Al2O3), Ruthenium Oxide (RuO2), Titanium Oxide (TiO2), Cerium Oxide (CeO2), Graphene Oxide, Multi-walled Carbon Nanotubes (CNT) and other nanoparticles, in biodiesel engine. It focuses on their unique properties, characterization, emission control, environmental impact, and engine performance. The study emphasizes the significance of different biodiesel blends, compositions, and nanoparticle additions in determining engine performance and emissions. Results vary based on nanoparticle type, size, concentration, and blend composition. The review examines the impact of nanoparticles on various aspects of biodiesel blends, including density, viscosity, cetane number, calorific value, and flash points. It found that nanoparticle additives significantly influence Brake Thermal Efficiency and combustion efficiency. The study also found that nanoparticle-enhanced biodiesel blends have improved ignition properties, faster evaporation, higher oxygen content, and elevated cetane numbers, leading to cleaner combustion and more environmentally friendly engine operation. The research supports the beneficial effects of nanoparticles on biodiesel characteristics and emissions reduction. The review suggests that nanoparticles in biodiesel engines can improve fuel characteristics, engine performance, and emissions reduction but cautions against potential environmental and health risks. The findings suggest further research and optimization for sustainable and efficient engine performance in pursuing greener transportation fuels, highlighting the potential of nanoparticles in biodiesel blends.

The study proposed the removal of Brilliant Green, a cationic dye, by adsorption process from wastewater solution utilizing a low-cost adsorbent such as Nutraceutical Industrial Pepper Seed Spent (NIPSS). The study comprises an investigation of the parametric influence on the adsorption process. The parameters identified are pH, dye concentration, process temperature, quantity of the adsorbent, and particle size. The study of statistics found from experiments was carried out by incorporating Freundlich, Brouers-Sotolongo, Langmuir, Toth, Sips, Jovanovic, and Redlich-Peterson isotherm models. The adsorption kinetics were determined by implementing pseudo-first-order and second-order models, diffusion film models, and Dumwald-Wagner and Weber-Morris models. The experimental adsorption capacity qe was found to be about 130 mg/g. This value was closest to the maximum adsorption of 144.6mg/g predicted by the Brouers-Sotolongo isotherm which had a correlation coefficient (R2) of 0.998. The adsorption kinetics data was confirmed to be a pseudo-second-order model. The change in free energy, enthalpy change, and entropy change were vital thermodynamic factors in concluding that adsorption is almost spontaneous and endothermic process. Change in enthalpy (ΔH°) reduced value indicates the physical nature of the process. The adsorption of BG dye on the adsorbent surface was authenticated by FTIR spectroscopy and SEM imaging. A Central Composite Design (CCD) Quadratic model under Response Surface Methodology (RSM) was implemented for statistical optimization of adsorption capacity for the five parameters studied, namely, time, temperature, concentration of the dye, weight of the adsorbent, and pH. Software Design Expert 7.0 was used to evaluate 3D contour plots. The process of optimization yielded a value of 350 mg/g. Thus, incrementing the adsorption process by 84.2 %. The study provides insights on various dye and adsorbent interaction possibilities and derives that NIPSS is an efficient adsorbent to extract BG dye from wastewater solutions.

Cardiovascular diseases, particularly coronary artery disease, pose big challenges to human life. Deployment of the stent is a preferable treatment for the above-mentioned disease. However, stents are usually made up of shape memory alloy called Nitinol. The poorer surface finish on the machined nitinol stents accelerates the migration of Nickel ions from the implanted nitinol stent, which is considered toxic and can lead to stenosis. The current study deals with controlling surface quality by minimising surface roughness and improving corrosion resistance. Femtosecond laser (fs-laser 10−15 s) micromachining was employed to machine the Nitinol surface to achieve sub-micron surface roughness. The Grey relational analysis (GRA)-coupled design of the experimental technique was implemented to determine optimal levels of four micromachining parameters (laser power, pulse frequency, scanning speed, and scanning pattern) varied at three levels to achieve minimum surface roughness and to maximise the volume ablation. The results show that to yield minimum surface roughness and maximum volume ablation, laser power and scanning speed are in a higher range. In contrast, the pulse frequency is lower, and the scanning pattern is in a zig-zag manner. ANOVA results manifest that scanning speed is the predominant factor in minimising surface roughness, followed by pulse frequency. Furthermore, the corrosion behaviour of the machined nitinol specimens was evaluated, and the results show that specimens with lower surface roughness had lower corrosion rates.

The increase in strength and stiffness of a metal matrix composite connecting (MMC) rod when compared to conventional rods have motivated researchers in this area. This opens a new window for the present research, here Al7075 alloy and Al7075-based composite connecting rods were fabricated by machining composite blocks using computer numerical control machining centre. Al7075-based composite connecting rods comprises of 91 % Al7075, 3 % hexagonal boron nitride (h-BN) and 6 % of zirconium dioxide (ZrO2). Modal characteristics and mechanical performance of the prepared components were analysed. An experimental modal analysis was conducted on the connecting rod under fixed-free condition to identify the natural frequency and its mode shapes, further the outcomes were compared with the numerical values. The ANSYS workbench is used to estimate the component's failure load based on finite element (FE) approach. The results obtained from modal analysis revealed that the composite connecting rod is more dynamically stable than its unreinforced counterpart. Composite connecting rods also showed better load-bearing capacity as compared to Al7075 in terms of tensile and compressive loading. Failure load analysis results indicate that under compressive load the component bends along the shank (I-beam), while under tensile load, cracks originate at the section connecting the piston pin end and the I-beam. The composite connecting rod sustained 13.5 % higher compressive load and16.5 % higher tensile load than the Al7075 connecting rod, making it a suitable alternative material. The failure mechanisms have been investigated by extensive scanning electron micrography of fabricated connecting rods.

Fluid–structure interaction has been widely studied in the last few decades due to its wide range of applications in engineering fields. This phenomenon plays an important design role, for example, in offshore risers, high slender buildings, chimney stacks and heat exchangers. The vortex shedding generated from a bluff body can induce high-amplitude oscillations, known as vortex-induced vibrations (VIVs). This study presents a numerical analysis to investigate the impact of surface roughness on VIV in the crossflow direction of a circular cylinder. The study also investigates the impact of surface roughness with variation in mass ratio from 2.4 to 11 at a high Reynolds number (Re) = 104 using Reynolds-averaged Navier–Stokes (RANS) equations. The study concludes that roughness on a cylinder results in a reduction in amplitude response. Furthermore, the lock-in region is narrower compared to that of a smooth cylinder, irrespective of the mass ratio. However, it is observed that the impact of surface roughness is more significant in high-mass-ratio cylinders where the lock-in region is more squeezed and shifted toward lower reduced velocities. Furthermore, the vortex mode beyond reduced velocities Ur = 5.84 and 7.52 was observed to be 2S for high and low mass ratios, respectively.