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During the dyeing process, the color is maintained over time due to the mordant that creates a strong bond between the dye and the fiber. The most common chemical mordants are potassium alum, tartar cream, tin chloride, cupric sulfate, ferrous sulfate and potassium dichromate. The current trend of increasing nature protection requires the use of clean products for the textile finishing sector and the biodegradability of textiles. Aloe vera is known to be a natural mordant. Based on data from the literature, the authors of this paper aimed to identify several behaviors between aloe vera gel and textiles. Aloe vera gel macerated onsida rhombifoliashows (with the residue in the oven) after IR analysis a disappearance of peak 1029 cm-1which indicated the degree of C-O-C bonds of cellulose present in the modification of sida rhombifolia. The active ingredients of Aloe vera have also been shown to bind to the hydroxyl groups of cotton, which is a crosslinking agent for macromolecules.

This work, which aims at realizing a synthesis of the knowledge on cutaneous microbes, shows that the skin is made up of pathogenic microbes and commensal microbes. The resident or commensal microbes are defenders of the skin and are ready to compete for nutrients and available space. Therefore, pathogenic microorganisms will not be able to settle and grow. The textile designer, in his search for an antimicrobial textile, should not be satisfied with the ability to inhibit skin microbes. He should investigate whether his textile promotes the balance of the commensal flora before testing the inhibition of the transient flora. For this reason, it is desirable to know the skin flora before embarking on the implementation of antimicrobial textiles.

This chapter highlights the typology of road accidents related to the default of signing for many accidents have occurred due to imperfect signposting along roads in Cameroon. The Yaounde-Douala highway has been chosen for this study. Available Field data recorded during the years 2007, 2009 and 2011, have enabled the analysis of each accident. It appears that amongst the 569 accidents recorded along a section of 114 km, 108 cases (about 20%) result from the default or lack of signing. From a clinical analysis, four scenarios of accidents that occurred by collision were found on one hand, and on the other hand, seven were elaborated based on factors such as: no signposting at crossroads, the lack of vertical and/or horizontal alignment or slightly raised bump and the deficiency of signpost for normal parking layouts or no parking at certain critical points.

This work aims to develop and characterize a hybrid composite material with two particles of the same size. As reinforcing particles, the hulls of palm nuts and coconut are chosen. Hybrid composite material composites in the form of specimens were produced by molding at 10%, 20% and 30% mass fractions in various sizes (0.63 mm, 1.25 mm and 2.5 mm). The samples were physically characterized (water absorption rate, moisture content, actual, theoretical and apparent density) and mechanical in 3-point flexion. The main results are: the highest and minimum water absorption rate is respectly 3.57% and 0.67% for respectly particle sizes 1.25 mm (sample P10C30) and 0.67% in the size of 0.63 mm (sample P10C10). The moisture content varies from 0.64 to 7.14% respectively for the P20C20 (2.5 mm) and P10C30 (2.5 mm) samples. The maximum and minimum real density are 1340,518 Kg/m3 and 1055.981 Kg/m3, for respectly the composites of particles sizes 1.25 mm (P20C10) and 0.63 mm (sample P20C20). The minimum real density is Its maximum theoretical density is 1194.949 Kg/m3 (for samples P20C10, P10C10 and P30C10); however, the minimum is 1189.966 Kg/m3 (P10C20 and P20C20). The bulk density varies from 933.28 Kg/m3 to 1176.1 Kg/m3, respectively, in sizes from 2.5 mm (P10C30) to 0.63 mm (for P10C30). As for the mechanical characteristics, the Modulus of Elasticity (MOE) varies from 25.664 GPa to 25.759 GPa, respectively, the samples P10C10 (1.25 mm) and P10C20 (2.5 mm). The MOE values describe a parabola whose peak is reached when the palm shell loads are 20%, that is to say P20C10, whatever the particle size distribution. In resilience, samples with small particles are more resilient with a maximum value of 22.49 J/cm2 and a minimum value of 4.45 J/cm2 to verify the principles of Hall-Petch's law.

This work is the study of the thermal point of view of the mixtures of the copolymer (PP/EPR) with calcium carbonates socal312, socal322v, Winnofil spm marketed by Solvay trading company. Calcium carbonates have the mechanical reinforcement role of copolymer (PP/EPR). The present study focuses their effects on the thermal properties of the said copolymer. An analysis and comparison of DSC curves, summary tables of mixtures properties are made according to the type of machine used to carry out the mixtures (a micro twin screw or an internal mixer HAAKE Poly Lab System) and the rate of each type of reinforcement of calcium carbonate (5% and 10%) in the copolymer. After tabulation of results, it is shown two observations: first the presence of each type of calcium carbonate used, does not change the melting and crystallization temperatures of mixtures and this regardless of the reinforcements rates; afterwards, calcium carbonates generally decrease the thermal properties of the copolymer regardless of the type of mixer used, this constitutes a double advantage: calcium carbonates reinforce the matrix while reducing the energy cost implementation. This phenomenon is much more pronounced when using Winnofil spm at low rates of reinforcement. These results are consistent with those provided by the literature, and have in additional, that they provide more curves and detailed tables of DSC test values and situational analysis for the types of components used in our study (copolymer PP/EPR mixed with calcium carbonates Socal312, Socal322v or Winnofil spm).