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The size and shape of solar box cooker is determined by the volume of the vessel, which in turn depends on the number of family members. The primary objective of this study is to overcome the obstacles inhibiting researchers from crafting solar box cookers tailored to their specific research needs, as well as hindrances preventing manufacturers from effectively bringing them to market. This experimental study aims to identify two novel optimal volumetric efficiencies (VE1and VE2) to minimize cooking time. To achieve this goal, we employed two identical solar box cookers made from the same materials and four vessels. The results obtained clearly show that the absorber temperature reached a maximum value of 124.9 °C and the boiling time was the shortest 02h50 when the first volumetric efficiency VE1had the least value of 6.2% and the second volumetric efficiency VE2had the greatest value of 100%. It is concluded that these two volumetric efficiencies could serve as benchmark parameters for future research, providing a standardized reference for developing solar box cookers of varied shapes and sizes under the same climatic conditions.

In this study, peanut shell-derived activated carbon, produced by orthophosphoric acid activation, was used as a material to adsorb methylene blue (MB). An optimization process was conducted to determine the optimal values for the adsorption parameters, including adsorbent dosage, temperature, pH, and contact duration. The outcomes of experiments were analyzed using four adsorption isotherms, while the pseudo-first and second-order models were deployed for assessing the kinetics. The adsorption of MB achieved equilibrium after 120 min, following the pseudo-second-order kinetic model. The Langmuir model accurately represented the sorption process and achieved a maximum amount adsorbed of 219.7 mg/g at 25 °C. The thermodynamic variables (ΔH0, ΔG0, and ΔS0) were calculated by investigating the impact of temperature, revealing that the adsorption was both exothermic and spontaneous. Carbon functionalization with Fe3+or Ca2+ions enhances the adsorption capacity and expedites the adsorption process, with equilibrium being achieved in 70 min and 50 min, respectively.

Airborne particulates were collected daily during three year seasons by using medium-volume aspirating systems equipped with PM10 inertial impactors. The organic fraction was solvent extracted with soxhlet, fractioned and cleaned-up through column chromatography, then processed by gas chromatography combined with flame ionisation and mass spectrometry detectors. Chemical analyses allowed characterising a set of groups of compounds, namely n-alkanes, n-alkanoic acids, dicarboxylic acids, polycyclic aromatic hydrocarbons, nitrated polycyclic aromatic hydrocarbons, and highly-polar chemicals. Besides that, the potential sources of pollution were investigated by analysing the n-alkane carbon preference index and selected diagnostic ratios among PAH and NPAH concentrations. Total concentrations of n-alkanes varied widely over the study period (from 48 to 170 ng m−3); PAHs behaved similarly (2 ÷ 24 ng m−3). Caffeine and nicotine accounted together for ∼12% of all identified PM components in the Rouiba urban area during summers and this percentage raised up to ~65% in autumn 2007.