Fruits and vegetables are the most beneficial foods for health, so their consumption throughout the year is necessary. But its presence is generally limited to its harvest season, for this reason preservation is necessary to make it available, but their conservation in its fresh form can cause deterioration and growth of bacteria. Drying method of fruits and vegetables in the industry aliment is an effective solution, several research focuses on thermal or non-thermal drying methods to decrease the water content of these vegetable products. The aim of this article is to study a cold drying process under reduced pressure (non-thermal). It is based on molecular sieves having good selectivity toward water molecules. The dehydration of fresh and pre-treated apple slices by freezing with a thickness of 7 mm was carried out alongside a comparison with apple slices dried by convective drying (thermal). It was concluded that the maximum water is eliminated after 12 h of drying. In return, we observe that the drying time of frozen apple slices is equal to 7 h with a greater reduction in water content. This allows us to understand the effectiveness of freezing pretreatment on water transfer. Characterizations of fresh and dehydrated apple slices are carried out such as water activity, color, and hardness. Additionally, measurements of temperature, pressure and humidity within the enclosure are determined by an “Ardouino” sensor. Finally, a determination of the appropriate model for the drying experiments was carried out using mathematical models such as Newton, Page, Midilli et al.
Since its introduction in 2014, Tunisian farmers in the northern regions have shown increasing interest to cultivate oilseed rape (Brassica napus L.) due to its industrial and economic benefits. Many bioagressors attack this crop, like blackleg disease, caused by Leptosphaeria maculans-Leptosphaeria biglobosa a complex of fungal species. However, the lack of an integrated management strategy has highlighted the need to conduct research and test the efficacy of commercially available fungicides against L. maculans. This study aimed to evaluate the potential of three broad-spectrum fungicides (Mastor®, Prosaro®, and Progreen®) against L. maculans by assessing their growth rate and inhibition percentage. A total of twenty Tunisian L. maculans isolates from the 2019–2020 growing season were exposed to V8 juice-agar media supplemented with three different concentrations of each fungicide: half, equal and double the recommended dose. ANOVA with post-hoc Tukey HSD tests were performed to evaluate the significance of differences between different treatments and controls. The fungicides Prosaro® and Progreen® consistently demonstrated the highest inhibition percentages (100
In the context of decarbonizing the heating energy sector and reducing the emission of GreenHouse Gasses (GHG), shallow geothermal resources are considered one of the most potential and promising options for an environmental friendly heat supply. Despite the undeniable advantages of these systems, their use is still limited in certain applications and regions, generally due to the high initial investment usually associated with these installations. In order to contribute to the expansion of these systems and the optimization of their operation, this research focuses on the modeling of a closed-loop geothermal well to evaluate the influence of the grouting material on the overall system performance. This essential component directly intervenes in the heat exchange between the ground and the heat transfer fluid. Based on previous experimental laboratory tests performed on different grouting materials, the present work provides a mathematical modeling of the geothermal exchange in which the tested geothermal grout and the thermal conditions surrounding ground are varied. These models are fundamental to globally analyze the energy performance of the system under different grouting materials (with specific thermal and mechanical properties) and external operating conditions. Results show that beyond what the specific measurements on the analyzed samples provide, the modeling of the whole geothermal system is essential to establish the most suitable grouting material according to the particularities of the subsoil environment. The developed mathematical model constitutes a valuable tool for the optimal management of shallow geothermal resources so that, as in this case, the most appropriate grout is identified with the aim of ensuring the correct operation of the system during the planned useful life period and with the maximum possible performance. All these outputs are expected to have a significant impact on establishing the ideal operational pattern, thus making the use of these resources more extensible to the potential user.
The region of Arich is located in the southwestern part of Tunisia, precisely in the south-west of the region of Gafsa, marked by an arid climate. The extension of the cultivated lands and the industrial development has exacerbated enormously the volumes of groundwater used. In this region, the Plio-Quaternary water table contains salty water. The aim of this study is to identify the cause and the process responsible for the salinization of this water table. The chemical parameters were measured. These included electrical conductivity, pH, temperature, anions and cations concentrations. The interpretation of the analytical results of the hydrochemical study has been carried out through ion correlations. These results show that the origin of the salinization is related to the dissolution of evaporite minerals (halite, gypsum and anhydrite). The geophysical approach by electrical resistivity tomography, allowed to determine the extension of the salinity, by showing the presence of two zones, characterized by different qualities of waters. In this study, the hydrochemical results have confirmed and clarified what was obtained by the geophysical approach.
Heavy metal pollution is a serious environmental problem that many researchers across the world focus on in order to limit and reduce the induced toxicity effects on flora. One of the several applications adopted to resolve the metallic stress problem is soil amendment by biochar. Biochar is able to turn down metals translocation from the culture medium to plants. To more explore this application, we have studied the effects of simultaneous nitrogen fertilizer and biochar doses addition in Cd-contaminated soil, on tomato plants’ growth. For this reason, we have applied different biochar levels (0
