Yohanis Dabesa Jelila

This study presents a systematic investigation of the structural, thermal, and morphological characteristics of starch–PVA reinforced cactus bio-based composite films using FTIR, DSC, XRD, TGA, DMA, and SEM analyses. FTIR results suggested enhanced intermolecular hydrogen-bonding interactions among starch, PVA, and cactus-derived polysaccharides, with possible minor ester-link formation in the presence of citric acid. DSC analysis showed a glass transition temperature (Tg) in the range of 38–40 °C and a minor endothermic transition near 83 °C associated with bound moisture relaxation. The thermal transitions observed using the PerkinElmer DSC 9 were reproducible across replicate measurements, indicating good thermal consistency of the developed composite system. XRD analysis indicated a predominantly amorphous morphology with limited semi-crystalline domains and a crystallinity index of approximately 23.32%. TGA results suggested improved thermal stability relative to plasticized starch systems, while DMA results indicated moderate storage-modulus retention and viscoelastic stability over the investigated temperature range. SEM observations of tortuous crack propagation pathways and localized deformation mechanisms. The combined results indicate that the developed composite exhibits balanced thermal and structural performance and potential for sustainable flexible bio-based material applications. However, additional mechanical, durability, water-resistance, and comparative performance studies are necessary to evaluate its suitability as a leather substitute.

The improvements in the sheet metal industry have largely been influenced by the improvements in the formability of the material, modernized tools, computer simulations, and flexibility of the processes. Although these innovations have helped in reducing costs and reducing production cycles, there are also challenges that have to be addressed. In the present study, EDD 513 steel used for manufacturing of automobile oil drain cup having thickness of 1.5 mm was investigated through finite element analysis (FEA) and experimental validation for deep drawing operation. Few simulations conducted during intital phase resulted in excessive thinning of approximately 16% along with severe wrinkling at the flange region, leading to rejection of the tooling design. Parametric investigations were performed by varying die entry radius range from (4–11 mm), varying friction coefficient, blank holding force and die-punch clearance (0.31 mm and 0.82 mm). The optimized conditions obtained through FEA simulations demonstrated that an 11 mm die entry radius provided acceptable formability and satisfied industry requirements for defect-free production.The thinning percentage was reduced to 14% with low wrinkle formation at body and flange. The experimantal trial shows the inline aggrement with simulations results with devation of 3% in thickness and geometry.The findings underscore the significance of process parameters like friction, die entry radius and punch-die clearance in creating the best formability in the part.

The growing need for energy around the world is putting pressure on established power sources like fossil fuels, making renewable energy solutions more concern. The high calorific value of hydrogen has made it an attractive technique for increasing combustion rates. To get the best possible results from a dual biodiesel blend of juliflora and kapok, this research seeks to improve the hydrogen enrichment ratio. When compared to diesel, the combined effects of 12H ₂ + JK B20 increased BTE by 11.5%, CP by 6.9%, and HRR by 5.9%. The use of H ₂ and JK B20 improved combustion, leading to a decrease of 8.5% in BSFC, 10.9% in CO and HC emissions, 11.5% in smoke, and 14.6% in both. The increase in NOx emissions is a result of the trade-off. The RSM results demonstrate that the test blend B20, which included 12% H ₂ at 100% load, exhibited an attractiveness index of 0.995. An effective and trustworthy prediction framework for optimizing CI engine properties, the ANN model was fitted using experimental data and validated. Sustainable transportation and environmental protection stand to benefit greatly from the synergistic effects of H ₂ enrichment and dual biodiesel.

In recent days natural fibres are gaining lot of interest for the development of polymer composites as an alternative to conventional fibres such as carbon, glass, aramid, due to their low cost, relatively good mechanical characteristics, high specific strength, nonabrasive, eco-friendly, and biodegradability. In the present work, treated Kigellia Africana (sausage) fruit fibres are reinforced with epoxy resin, composites were fabricated and characterized for their structural, mechanical, wear, vibration characteristics. Mineral salts, dirt, inorganic residues, leftover fruit pulp, and waxy materials were all eliminated using hydrochloric acid (HCl) treatment. Following the bleaching of the treated material, its properties were assessed and characterized. After the alkali treatment and bleaching, a substantial level of lignin and hemicellulose were removed, resulting in a highly cellulosic fibre with improved characteristics. Results showed that the HCl-treated fiber composites with cenosphere demonstrated their viability for load-bearing applications with tensile strengths of 32.24 MPa (96% improvement) and flexural strengths of 50.28 MPa (39.8% increase). The structure and uniform distribution Kigelia africana fibers were responsible for a maximum hardness of 34 RHN (57% greater), whereas RSM analysis showed minimal wear at 25 N load, 3000 m sliding distance, and 0.5 m/s velocity.

The suspension system plays a significant role in ride comfort, car weight support, and road handling, which is crucial for the safety of the ride. This paper illustrates a derivation of a mathematical model and proportional-integral-derivative (PID) controller design for an active suspension system for a quarter car model of a passenger car. The performance of an active suspension system in terms of the vertical acceleration of the car body, suspension deflection, and tyre deflection is compared with that of a passive suspension system when subjected to road disturbance. The results show that the active suspension system with PID controller provides better performance compared to that of the passive suspension system.