Soot particles have been associated with respiratory diseases and cancer. To decrease these emissions, perovskite-mixed oxides have been proposed due to their thermal stability and redox surface properties. In this work, SrTiO 3 doped with different amounts of Mn were synthesized by the hydrothermal method and tested for soot combustion. Results show that at low Mn content, structural distortion, and higher O ads /O lat ratio were observed which was attributed to the high content of Mn 3+ in Ti sites. On the other hand, increasing the Mn content led to surface segregation of manganese oxide. All synthesized catalysts showed mesopores in the range of 32-47 nm. In the catalytic combustion of soot, the samples synthesized in this work lowered the combustion temperature by more than 100 • C compared with the uncatalyzed reaction. The sample doped with 1 wt % of Mn showed the best catalytic activity. The activation energy of these samples was also calculated, and the order of decreasing activation energy is as follows: uncatalyzed > Mn0 > Mn8 > Mn4 > Mn1. The best catalytic activity for Mn1 was attributed to its physicochemical properties and the mobility of the oxygen from the bulk to the surface at temperatures higher than 500 • C.

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In this study, multidisciplinary teams were formed to develop educational content as digital videos to help in the learning process in Science, Tech-nology, Engineering and Mathematics (STEM) education. The usefulness of the web-learning tool was evaluated by surveys and tests taken by chemical engineering freshman students. The results showed that these students’ scores were higher than the scores obtained by students of previous courses where the web-learning tool was not employed. On the other hand, the au-dience analysis indicated that the average age is 18-24 (91.2%) and the gen-der distribution was 54.9% male and 46.6% female from different countries (Mexico, Colombia, Spain, U.S., among others).

In this work it was determined the effect of fly ash (FA) as bonding material during the fabrication of low thermal expansion porous materials. SiC, fly ash, Vitrified Bonding Material (VBM), and LiAlSiO4 powders were used as raw materials. Porous materials were sintered at 850°C and 950°C after manual milling and mechanical milling in a planetary ball milling at 800 RPM. SEM micrographs showed the presence of porous materials, and it was observed that fly ash particles did not melt at 850°C. However if sintering temperature increases at 950°C, FA starts to melt and it is forming bridges between SiC particles. Thermal expansion values were around 3.0x10-6 K-1. According to these results, it seems that it is possible to have a favorable synergy between FA and VBM to fabricate SiC porous materials with low thermal expansion values.