The study of heat transfer in frequency dynamic regime established helped define the thermal impedance of the material. The material is a plane wall composed of kapok-plaster with thickness of 0.01 m and a thermal conductivity 0.1 W/mK. The thermal behavior of the studied material is highlighted by showing the influences of heat transfer coefficients and external excitation pulse. L'evolution de la capacity equivalent intérêt Donnée en fonction de la pulsation excitatrice Extérieure. The evolution of the equivalent capacitance is given as a function of the external excitation pulse; the influences of the depth of the material, his diffusivity and heat exchange coefficients are shown.

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Clay is currently experiencing a renewed interest following energy crisis and that of housing. It is therefore important to estimate the thermo-physical and mechanical parameters of this material which is used among things as building material. We present in this study, the results of the thermo-physical and mechanical properties of clay from BANGA BANA quarry, mixed with cow dung. BANGA BANA is a neighborhood in the city of Niamey in Niger, located on the right bank of the Niger River. This mixture is used to make bricks for the construction of houses in Niamey. The results obtained show that the conductivity and effusivity of this clay decrease depending on the content of cow dung. Regarding resistances to compression, they are present to a maximum when they are represented depending on the percentage of cow dung. The stabilization of the mixture is obtained by adding cement.

This study focuses on the study of the behavior of aluminum alloys based utensils in Senegal against some daily food products such as rice (main cereal consumed) and tomato. The results of experiments show that these alloys, which do not respect the current standard NF EN 601 of July 2004, are generally more degraded when cooking foods aforementioned than the control sample which respects it. Mass losses are significant and go up to 0.2 mg/cm²/h for rice, as they are barely detectable for tomato. The mechanism of corrosion was exposed and appears to be related to the microstructure and chemical composition of the alloys. The presence of metallic ions is also detected in the substrates. Thus, given the daily use of these utensils to prepare more often rice, the issue of health consequences arises. A work with specialists health care partners is ongoing. However it would be interesting to see in future studies how to limit this degradation against rice.

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