2015): Synthesis of iron sulfide films through solid-gas reaction of iron with diethyl disulfide, Journal of Sulfur Chemistry, Iron sulfide films were synthesized by the solid-gas reaction of diethyl disulfide on iron foils in the temperature range of 658-768 K using a microbalance, where the film growth kinetics followed Deal-Grove behavior. Analysis of the films by X-ray photoelectron and Raman spectroscopies as well as X-ray diffraction and scanning electron microscopy analysis revealed the formation of combined FeS/FeS 2 (troilite/pyrite) films with a sheet-like morphology at low temperatures and only FeS (troilite) films with granular morphology at higher temperatures.

This study presents a prospective study for the potential exploitation of pelagic Sargassum spp. as a solid biofuel energy source. It was carried out in three stages. First we conducted a morphological, physical-chemical, and structural characterization using scanning electron microscopy (SEM), infrared spectroscopy (FTIR), and X-ray diffraction (DRX), respectively. Second we evaluated the material’s functional properties as a solid biofuel based on its calorific value and the quantification of polymeric components like hemicellulose, cellulose, and lignin, as well as thermogravimetric and differential analysis to study the kinetics of its pyrolysis and determine parameters like activation energy (Ea), reaction order (n), and the pre-exponential factor (Z). Third we analyzed the energetic potential considering the estimated volume of pelagic Sargassum spp. that was removed from beaches along the Mexican Caribbean coast in recent years. Results of the kinetic study indicate that Sargassum spp. has an enormous potential for use as a complement to other bioenergy sources. Other results show the high potential for exploiting these algae as an energy source due to the huge volumes that have inundated Caribbean, West African, and northern Brazil shorelines in recent years. As a solid biofuel, Sargassum spp. has a potential energy the order of 0.203 gigajoules (GJ)/m3. In the energy matrix of the residential sector in Mexico, its potential use as an energy source is comparable to the national consumption of firewood. The volume of beachcast Sargassum spp. that was removed from ~8 km of coastline around Puerto Morelos, Mexico in 2018–2019, could have generated over 40 terajoules/year of solid biofuel.

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The COVID-19 pandemic has generated multiple impacts. In particular, in the educational sector, the virtual class modality generated changes in the patterns of energy consumption at the institutional level; the identification of this consumption will allow us to reflect on new energy saving and efficient use strategies. In this research, we present a case study of the effects of the COVID-19 pandemic on electricity consumption in 13 state universities in Michoacán, Mexico. Electric energy consumption has been evaluated before and during the presence of the COVID-19 between 2019 and 2020. The comparative analysis estimated the reduction in energy consumption and its economic and environmental impact. The results show a considerable decrease in electricity consumption, generating an average saving of 76.24 MWh/month, which translates into an annual emission reduction from 2019 to 2020 of approximately 497 TnCO2e, and in economic terms of $8,882.25 USD each month. In general, it was identified that consumption patterns in the use of machinery and computer equipment for administrative activities were drastically reduced. If education continues in virtual or hybrid modes, energy consumption schemes will continue to decline and institutions could move towards resilient, affordable, and sustainable models of energy production and consumption.

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The energy use of fruit tree pruning represents a current alternative to achieving an energy transition toward clean biomass resources, which can substitute for fossil fuels and mitigate polluting emissions. In Mexico, avocado is one of the most important fruit crops, with approximately 260,000 ha planted. The pruning of avocado trees generates large amounts of biomass that are not fully exploited, lacking studies that analyze in depth the energy potential of pruning. This study aims to determine the potential energy use of avocado pruning as densified solid biofuels. The physical, chemical and energetic properties of two pruning fractions defined as class B (branches) and class BAL (branches and leaves) were determined. From class B, pellets were made, and their physical and mechanical properties were determined. Subsequently, the evaluated parameters of the pellets obtained were compared to European quality regulations to determine their quality and identify their potential uses. The characterization of avocado pruning indicates that class B generally has better physicochemical characteristics than class BAL to be used as solid biofuel. It was found that class B has a high calorific value (19.61 MJ/kg) and low ash content (1.2%), while class BAL contains a high amount of ash (7.2%) and high levels of N (1.98%) and S (1.88%). The manufactured pellets met most of the quality requirements for immediate use in the residential, commercial and industrial sectors at the regional level.