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The expanding field of alternative proteins represents a transformative approach to addressing global food security and sustainability challenges. Among these, fermentation-derived alternative proteins cultivated from microorganisms such as fungi, bacteria, and algae offer a promising avenue for sustainable protein production. This review explores the selection and utilization of raw materials to produce microbial proteins through fermentation processes. Critical raw materials include agricultural byproducts, industrial waste streams, and specifically designed feedstocks, which not only mitigate environmental footprint but also enhance the economic viability of production systems. The utilization of lignocellulosic biomass and molasses has demonstrated considerable promise, attributed to their abundant and renewable nature. The review underscored the necessity of exploring specific areas to enhance the viability of producing microbial protein from diverse raw materials. These areas include improving pre-treatment strategies to enhance substrate suitability for fermentation, optimizing fermentation processes for increased yield and reduced costs, and developing more resilient microorganisms capable of thriving on varied substrates. These strategies are crucial for advancing the production of alternative proteins through fermentation, in addition to raw material selection, which is vital in the scalability and sustainability of alternative protein production through fermentation, emphasizing the need for continued research and innovation in this field.

Due to climate change and hot summers in most of Algeria’s regions, air conditioning has become a thorny issue, resulting in excessive energy consumption. This research focuses on the implementation of dew point evaporative coolers as an alternative to conventional air conditioners. The desirability function approach is used to predict the optimal operating parameters and compare the thermal performance and water consumption of two dew point cooler configurations (counter flow-regenerative cooler and combined parallel–regenerative cooler) under different climatic conditions in Algeria. A numerical model is developed and validated using literature data for regenerative and combined dew point evaporative systems. Parametric analysis and multi- to single-objective optimization simulations were performed with the GenOpt simulation software, identifying the most influential parameters and predicting the optimal conditions for both configurations. The findings suggest that the optimal channel spacing, working air ratio, and primary air velocity are identical for both technologies.

AbstractThe paper aims to present a new insulating material based on cork aggregates and cement designed for building applications. Samples are prepared by mixing natural cork aggregates, sand, cement and water. Four cork volume dosages are considered, 0, 25, 50 and 75% (relative to the sand). Samples are characterised in terms of hardened density, compressive and flexural strength, as well as thermal conductivity and hydric properties (moisture content, vapour permeability, moisture buffering value and absorption by partial immersion). Results show that increasing cork granule amount tends to increase moisture retention and buffering value but decreases density, thermal conductivity and mechanical properties. Depending on the cork content, cork concrete mixture can be used as thermal insulator or as a structural component.

The TackSHS project aims to comprehensively elucidate the impact that exposure to second-hand smoke (SHS) from cigarettes and second-hand aerosols (SHA) from electronic cigarettes have on the respiratory health of the European population according to socioeconomic characteristics and other determinants.

The aim of this work is to study the effect of the position of an obstacle in the U-shaped with length lr = 0.6Hand height hr = 0.4H, thickness wr = 0.2Hlocated inside a square cavity of two-dimensional length Land height Hfilled with a diamond–water nanofluid (solid volume fraction in the range of 0.05). The bottom wall of the cavity is brought to a constant hot temperature (Th). The two side walls are cooled to a constant temperature Tf, and the upper wall of the cavity is adiabatic. The position of the obstacle in relation to the hot wall was studied in four cases: in the first case, the obstacle is placed on the vertical left side wall, the obstacle is placed on the upper in case 2, (against a hot wall), the obstacle is placed on the vertical right side wall in the case three, and the fourth case the obstacle is placed on the hot wall. The effect of the obstacle dimensions, such as its thickness, length, and width in the fourth case, on heat exchange inside the cavity was also studied. Numerical results were developed for Rayleigh numbers equal to 103and 105for the laminar and steady flow regime. According to the results obtained from the study, the effect of increasing the Rayleigh number on the heat transfer coefficient was observed in the four cases. We found that the position of the obstacle in the fourth case gives the best heat exchange compared to the cases studied, with a difference of 8.8%, 11%, and 8.9% for the first case, the second case, and the third case, respectively. We also noticed that an increase in the thickness, length, and height of the obstacle affects the heat exchange in the fourth case.

This paper aims to study the thermal performance at wall scale of hollowed bricks made of starch/beet-pulp bio-composites identified as a potent solution for the development of sustainable, non-load bearing, insulation materials to be used in the construction sector. Numerical studies on thermal resistance using the COMSOL software were conducted to study the characteristics of optimal hollowed brick pattern. The numerical study results were then compared with thermal resistance calculations based on the NF EN ISO norm 6946 (2017). In a later stage, an experimental 1 m x 1 m wall made of starch/beet-pulp composite bricks and binder was built. Experimental studies on the thermal resistance and thermal imaging were carried out on the wall inserted in a bi-climatic chamber showing only a 3 °C change of the surface temperature of the wall on the one side after applying a 23 °C temperature difference on the other side for 7 h. The equivalent thermal resistances were obtained equal to 1.180 m2. K/W, 1.218 m2. K/W, 1.10 m2. K/W respectively as described previously which reflected a good agreement between the numerical and experimental results.Finally, the obtained results reflected the high thermal performance of the studied starch/beet-pulp composites.

Nous présentons une modélisation de la mesure de température de surface par thermocouple. La solution du modèle s'effectue par séparation de variables et par méthode des “quadripôles”. Cette dernière méthode permet une représentation élégante des résultats et une extrapolation simple. L'application du modèle permet de déterminer l'influence du détecteur de température sur la détermination de la diffusivité thermique par méthode “flash”. Des exemples pour un thermocouple à semi-conducteur et pour un thermocouple métallique sont donnés.

Le but de cette étude est de montrer que la méthode " flash " originellement utilisée pour la mesure de la diffusivité thermique de matériaux isotropes, peut être étendue à la mesure des diffusivités thermiques de matériaux anisotropes. Dans le cas de matériaux anisotropes se présentant sous forme de plaques de faibles épaisseurs (composite multicouche par exemple), il n'est pas possible de mesurer la diffusivité thermique dans le plan des plaques par la méthode, flash classique. Deux thermogrammes relevés sur la face opposée à l'impulsion permettent, par une comparaison à un modèle analytique d'identifier simultanément les deux diffusivités axiale (perpendiculaire au plan de l'échantillon) et radiale (dans le plan de l'échantillon), par la méthode des moments temporels partiels. Une installation a été développée et validée. Des résultats obtenus sur des composites Kevlar-Epoxy sont présentés.

This article presents a comparative study between two different geothermal systems: an earth air heat exchanger (EAHE) and seasonal storage systems. The energy efficiency of a combined geothermal system composed of two series of connected underground tanks coupled with a cooling floor and a PVC earth-air heat exchanger coupled to an experimental cell is presented through an experimental and numerical analysis. A measurement system is installed to study the thermal performance of both systems under the same conditions. The climatic conditions, the temperature at the outlet of the two systems were measured. This experimental protocol allows to evaluate and understand the interest of each system for cooling needs. Experimental results show that the energy performance of two systems is different. The blowing temperature of the EAHE varies between 19 and 24 °C, however the outlet temperature of the underground tank varies between 16 °C and 20 °C. Based on experimental data, a Long-Short-Term-Memory (LSTM) neural network algorithm is then used to forecast the underground tank and EAHE temperatures evolutions. The forecasting accuracy of the proposed model was evaluated using different statistical measures. The determination coefficient (R2), the Root Means Square Error (RMSE), and the Mean Squared Error (MSE) for the EAHE outlet temperature are 0.953, 0.093 and 0.306, respectively. Furthermore, the R2, MSE and RMSE for the underground tank temperature are 0.984, 0.165 and 0.406 respectively.

Context.The full three-year Wilkinson Microwave Anisotropy Probe results (hereafter WMAP3) reinforce the absence of large-angle correlations at scales greater than 60?. The Poincar? dodecahedral space?model, which may naturally explain such features, thus remains a plausible cosmological model, despite recent controversy about whether matched circle searches would or would not push the topology beyond the horizon.Aims.We have used new eigenmode calculations of the dodecahedral space to predict the cosmic microwave background (CMB) temperature anisotropies in such a model, with an improved angular resolution.Methods.We have simulated CMB maps and exhibited the expected self intersection of the last scattering surface along six pairs of circles. For a set of plausible cosmological parameters, we have derived the angular power spectrum of the CMB up to large wavenumbers.Results.Comparison of the angular power spectrum with the WMAP3 observations leads to an optimal fit with the Poincar? dodecahedral space?model, for a value ?tot = 1.018 of the total energy density parameter.

A water-cooled electromagnetic (EM) dipole, for intracavitary hyperthermia, embodying a metallic reflector to give directional characteristics to the SAR and then to the heating pattern in the biological tissue, is considered. The influence of the reflector on the SAR deposition has been theoretically modelled with an EM analysis which uses the method of moments (MOM). A thermal model, based on the heat transfer equation, is used to predict temperature distribution, which exhibits a directivity related to the angular extension of the reflector. Experiments have been carried out in a polyacrylamide phantom. The temperature distribution detected with a liquid crystal sheet shows fairly good agreement with theoretical predictions.