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In recent years Bio-lubricants much desired in numerous applications in machineries due to their renewable characteristics, which have high biodegradable nature and produce fewer pollutants compared to mineral-based lubricants. Thus, in this paper, the effect of bio-lubricant (Cucurbita Pepo L. seed oil) on wear and friction characteristics in pin on disc tester is studied and compared with commercially available lubricant SAE20W40. Tests were conducted at different loads of 10 N, 50 N, 100 N, 150 N and 200 N at a constant speed of 3 m/s for 60 min to evaluate the behaviour of friction coefficient (COF) and wear at a temperature of 28°C and 100°C. It is observed from the results that, the COF decreases whereas, the wear increases with the rise in temperature and load. Cucurbita pepo L. seed oil (CPO) resulted in a lower wear rate in comparison to commercial SAE20W40. Wear scars on the surface lubricated with SAE20W40 show a rougher surface compared to the pin lubricated with CPO at both lower temperature (28°C) and higher temperature (100°C). This shows that CPO has better lubricity than SAE20W40. The present work indicates that CPO can be a possible substitute to mineral-based lubricant SAE20W40 for higher-temperature workplaces. [ABSTRACT FROM AUTHOR]

Green-synthesized nanoparticles from pumpkin (Cucurbita pepo L.) seed extracts are economical and eco-friendly. Silver nanoparticles (AgNPs) and their selective cytotoxicity towards HCT116 and African Green Monkey Kidney, Vero cells were investigated. Chemical fingerprinting, heat stability, and 2D-images of nanoparticle size and morphology were determined using Fourier-transform infrared spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Transmission Electron Microscopy (TEM), and Scanning electron microscopy-energy dispersive X-ray (SEM-EDX) on AgNPs. UV-vis examination shows surface plasmons in the wide peak at 417 nm, indicating polydisperse nanoparticles. Small silver nanoparticles (AgNPs) below 2 µm demonstrated a rod-like form and a tendency to agglomerate. SEM-EDX element analysis and fingerprinting confirmed the material as AgNPs. TEM indicated that the nanoparticles were generally spherical or ellipsoidal, equally dispersed, and averaged 26.08 nm in diameter with negligible aggregation. The AgNPs are also stable at a temperature of 220°C, indicating that the green material is quite robust at 150°C to 400°C. According to cytotoxic studies, AgNPs are toxic to cancer cells (HCT 116 cells), however they have no effect on Vero cells. AgNPs and tubulin (TUB) domain active sites have a significant affinity, according to molecular docking analysis. In an electrochemical investigation, biogenic AgNPs effectively prevented mild steel from corroding in a 1.0 M HCl solution. [ABSTRACT FROM AUTHOR]

Biodiesel is produced from the refined/edible type oils using methanol and an alkaline catalyst which is one of the environmentally friendly alternative liquid biofuels that has proven itself commercially, with international standards all around the world. In present investigation, mixture of two biodiesels in equal weight ratio namely Cucurbita pepo.L (pumpkin) and Tectona grandis (teak) seed oil was used for the synthesis of biodiesel with 5-ml Diethyl ether as additive. Performance test was made with the biodiesel blend using water-cooled, constant speed, CI engine, and emission characteristics were analyzed using a five-gas analyzer. It was observed that there was 35.5% increment in Brake Thermal efficiency and 25.8% reduction in Brake Specific Fuel consumption at maximum load for 200-ml pumpkin and teak biodiesel blend mixed to the diesel with additive. For this blend, it was observed at maximum load, the emission of Carbon monoxide reduced by 26.67% of diesel; Carbon di-oxide reduced by 12.96% and Nitrous oxide reduced by 26.57%. The emission gets increased in over load condition. Unburned Hydro Carbon emission and smoke opacity increased by 67.16 and 9.84%. The combustion characteristics of blended biodiesel with additive closely followed the diesel fuel operation. Hence, this blend was used as fuel in CI engine without engine modification. [ABSTRACT FROM AUTHOR]