This study was conducted to fabricate and model a time–temperature label (TTL) based on paraffin wax and black carrot anthocyanin for monitoring fish products. A polar homogeneous wax was prepared using water, liquid paraffin, paraffin gel, cetyl alcohol, and citric acid. The prepared polar solid homogeneous wax was positioned on a paper smeared with pH-sensitive anthocyanin. The wax melted after being heated and flowed on pH-sensitive anthocyanin. The pH-sensitive anthocyanin smoothly showed color changes after contacting with wax. The efficiency of TTL was evaluated in the samples of farmed rainbow trout slices. Thiobarbituric acid reactive substances (TBARS), total volatile basic nitrogen (TVB-N), and sensory analyses were evaluated at the temperatures of −5, 5, 15, and 25 °C. The obtained values for TBARS, TVB-N, and color changes were plotted vs. time for all the temperatures and finally modeled by the Arrhenius equation, and activation energy values (E_a) were calculated. The fabricated TTL did not show color changes at the temperatures of −5 and 5 °C, but it showed color changes at the temperatures of 15 and 25 °C. The values of TBARS and TVB-N were significantly higher and the data for sensory analyses were smaller for the samples stored at the temperatures of 15 and 25 °C compared to those for the samples stored at −5 and 5 °C (P < 0.05). The obtained value for E_a (118.622 kJ mol⁻¹) was in the required range for quality indices in fish products. In conclusion, the fabricated TTL shows color changes at higher temperatures parallel to higher TBARS and TVB-N and lower sensory panels.

The environmental sustainability of agricultural and industrial vehicles, as well as of the transportation sector, represents one of the most critical challenges to the sustainable development of a nation. In recent decades, compression-ignition engines have been widely used in on-road and off-road vehicles due to their better fuel economy, autonomy, compactness, and mechanical performance (spec. the high torque values). Due to the consistent environmental impact of fossil fuels, scientists are searching for alternative energy sources while preserving the beneficial features of diesel engines. The utilization of blends of diesel fuel, biodiesel, and bioethanol fuel (referred to as “ternary blends”) is among the most promising solutions for replacing fossil fuels in the near term, allowing, at the same time, us to continue using existing vehicles until new technologies are developed, consolidated and adapted to the agricultural and industrial sector. These ternary blends can lower exhaust emissions without creating major problems for existing fuel-feeding systems, typically designed for low-viscosity fossil fuels. One of the concerns in using liquid biofuels, specifically biodiesel, is the high chemical affinity with conventional and bio-based lubricants, so the main parameters of lubricants can vary significantly after a long operation of the engine. The comprehensive literature review presented in this article delves into the technical challenges, the main research pathways, and the potential solutions associated with the utilization of biofuels. Additionally, it investigates the emerging application of nanoparticles as additives in lubricants and biofuels, highlighting their valuable potential. This study also discusses the potential implementation of bio-ethanol in ternary blends, offering a promising avenue for reducing reliance on fossil fuels while maintaining engine efficiency.

One of the technical possibilities to enhance the properties of lubricants and biolubricants is dispersing nanoparticles in them. Although conceptually simple, this operation faces challenges related to: (1) obtaining an initial good dispersion of the nanoparticles in the liquid and (2) ensuring the stability of this dispersion to avoid coalescence. The objective of this study is to verify possible improvements of the stability and characteristics of conventional and bio-based lubricants by efficiently dispersing in them surface-modified SiO₂ nanoparticles. The silane coupling agent KH570 was utilized to modify the surface properties of SiO₂ nanoparticles, facilitating their dispersion within the lubricants. Nanolubricants and nanobiolubricants were prepared using a two-step technique. The dispersion stability of these lubricants was assessed using sedimentation photography, FTIR, and UV-Vis spectrophotometric analyses. The addition of SiO₂ nanoparticles resulted in enhanced physicochemical properties of the resulting lubricant, including slight increases in density and viscosity, as well as a higher viscosity index. Chemical analyses, such as TAN and TBN measurements, confirmed that the nanoparticle addition at various concentrations (0.25%, 0.5%, 0.75%, and 1.0%) did not introduce critical acidity levels or compromise the alkaline reserve. ICP-OES analysis indicated minimal impact on essential additive concentrations, supporting the feasibility of SiO₂ nanoparticles in enhancing lubricant properties without destabilizing additives. The stability of the nanolubricants was monitored over 77 days, with visible sedimentation beginning around the 30th day and becoming more pronounced by the 54th and 77th days. Bio-lubricants exhibited slightly higher sedimentation than conventional lubricants. Optimizing the sonication time proved to be crucial, with longer sonication times (2.5 h) significantly improving the stability of nanolubricants across various concentrations of added nanoparticles. FTIR analysis confirmed the presence of SiO₂ and KH570, indicating no alteration to the basic functional structures of the lubricants and biolubricants. UV-Vis spectrophotometry further underscored the importance of optimizing sonication time for enhanced stability. Overall, this study demonstrates that incorporating surface-modified SiO₂ nanoparticles enhances the properties and stability of conventional and biolubricants, offering potential for improved performance in industrial and engine applications.

The need for the decarbonization of heavy-duty vehicles requires a deep understanding about the effects of biofuels, which represent a viable pathway to cut the emissions in the hard-to-abate sectors, like agricultural tractors. A novel meta-analysis approach can help to thoroughly investigate the effects of biodiesel blends on farm tractor engines in terms of performance and emissions. Studies were identified using the main keywords related to internal combustion engines in prominent scientific databases. Standardized mean differences were calculated for each study to evaluate engine performance and gas emissions. Mixed-effects regression models were developed to investigate performance and environmental pollution changes over different biodiesel blending ratios, biodiesel sources, and engine types. The analysis revealed significant effects of biodiesel blending ratio on decreasing torque [−13.0%, CI 95% (6.7%–19.3%); I² = 97.67; p = 0.000; Q = 129.94], engine power [−15.0%, CI 95% (10.0–20.0%); I² = 54.82; p = 0.000; Q = 101.81], CO₂ emissions [−24.1%(15.0–32.0%); I² = 0.198; p = 0.000; Q = 20.04], and CO emissions [−17.5%, CI 95% (16.0–18.0%); I² = 98.62; p = 0.000; Q = 97.69], while increasing specific fuel consumption [+5.2%, CI 95% (1.0–9.0%); I² = 95.94; p = 0.000; Q = 129.74] and NO emissions [+11.0%, CI 95% (6.0–15.0%); I² = 98.51; p = 0.000; Q = 157.56]. The same analysis did not show any influence of the sources of biodiesel and the engine type. Finally, meta-regression found a significant positive association between increasing ratios of biodiesels and decreasing torque, engine power, CO and CO₂ emissions, and increasing fuel consumption and NO emissions in terms of linear equations. Although through these equations it is not possible to individuate an optimal range of blending ratios able to lower the emissions and not affect the engine parameters, the range from 9.1% to 13.0% of biodiesel is a good tradeoff. Within it, the only decrease in engine performance is in charge of the power, however contained within 4%, while CO and CO₂ emissions are reduced (respectively by 0.0%/−2.8% and −3.6%/−6.0%) without using any specific pollutant abatement systems.