Conference Agenda

The study investigates the use of rose stems as a bioadsorbent for the removal of lead in contaminated aqueous solutions, taking advantage of plant waste from the flower markets of Arequipa, Peru. For this reason, the capacity of rose stems treated by a sequential process of acid and alkaline hydrolysis will be evaluated. The chemical activation of the rose stem biomass was carried out with a sequential process of acid hydrolysis and alkaline hydrolysis (TRHS) and was characterized by the Fourier Transform Infrared Spectroscopy (FTIR) technique before and after interacting with lead. The experimental equilibrium data are related to the Langmuir isotherm model and the lead biosorption kinetics fit better to the pseudo-second order Ho model. Therefore, a sequential acid-alkaline hydrolysis treatment (SAHT) was carried out to activate the biomass, resulting in a maximum adsorption capacity of 344.827 mg Pb(II)/g of rose stem and a lead removal rate of 99.325%, exceeding the results of other previous studies. The optimum pH for the biosorption process was determined to be 4, and ideal contact conditions and adsorbent dosage were established. The results suggest that the use of rose stems not only contributes to the circular economy by reusing waste, but also offers an effective solution for the removal of heavy metals in contaminated waters, highlighting its potential in environmental management and sustainability.

This study focuses on the application of non-Newtonian fluids, specifically shear-thickening fluids (STF), to improve the impact resistance of safety helmets. Given the growing need to protect workers in high-risk environments, it was explored how the incorporation of this type of fluid could increase the effectiveness of existing helmets. Therefore, the design and manufacture of an impact testing machine will be evaluated, as well as the evaluation of the hardness of aluminum plates using the Rockwell method. Through various tests, it was determined that helmets coated with STF showed a significant improvement in impact absorption, reaching an increase of 25.49% compared to standard models. The tests were carried out at different drop heights, with 1.92 meters being one of the most effective for measuring resistance. The results concluded that the use of non-Newtonian fluids, particularly STF, is feasible and potentially transformative in the design of personal protective equipment, underlining its importance in materials engineering and industrial safety. This work contributes to the creation of products that can provide better protection to people in vulnerable environments.

The arrival of COVID-19 posed a very important challenge for educational institutions, causing them to adopt different measures to guarantee healthy environments for a safe return to classes. However, knowledge about CO₂ as an indicator to know the conditions of air quality and the conditions it modifies with its presence was a mystery until the arrival of the pandemic. That is why, the objective of the present study seeks to analyze the relationship between environmental conditions and the concentration of this gas within the classrooms of a secondary educational institution, located in the city of Arequipa. The methodology used consisted of a non-experimental analysis, of correlational scope, obtaining the data through documentation, monitoring and observation of the 5 classrooms of the institution, finalizing its determination through the calculation of Pearson correlation coefficients. The results showed that there is a correlation between the variables, with temperature and CO₂ maintaining a strong positive relationship; unlike humidity, which demonstrates a strong negative relationship. Furthermore, about the percentage of occupancy and the opening of ventilation, the concentration of CO₂ varies in a direct and inverse proportion respectively. Finally, it is concluded that there is a relationship between the variables, where the measurement of the concentration of carbon dioxide turns out to be an adequate indicator to determine the quality of indoor air in classrooms by not exceeding the permitted threshold of 400 ppm, therefore special emphasis must be placed on the management of environmental conditions to avoid its variation.

This study was conducted at a sawmill to evaluate the effectiveness of a centrifugal fan in reducing respirable and inhalable dust concentrations during the wood planing process. Pre-intervention sampling was performed, where dust levels were measured for three days in five workers, using standardized NIOSH methods (0500 and 0600). Initial results showed weighted concentrations of respirable and inhalable dust that exceeded the established permissible limits, where respirable dust concentrations of 4,599, 5,109, 4,525, 4,681 and 5,595 mg/m3, exceeded the permissible limit value (PLV) of 3 mg/m3 according to D.S. 015-2005-SA. For inhalable dust, concentrations were 12,762, 10,875, 11,759, 13,217 and 11,316 mg/m3, also exceeding the VLP of 10 mg/m3. After the installation of the centrifugal extractor, a significant reduction in dust concentration was observed. Once the extractor was installed, post-monitoring of respirable dust concentration was carried out, obtaining values ​​of 1,276; 1,390; 1,399; 1,215 and 1,238 mg/m3. On the other hand, the inhalable dust values ​​are 1,971; 1,701; 1,922; 2,136 and 2,098 mg/m3, which are below the VLP. The extraction system efficiency reached 74.99% for respirable dust and 83.84% for inhalable dust. The data obtained show that, after the intervention, dust concentrations were within acceptable levels, in line with occupational health regulations and highlighting the importance of implementing control measures in the work environment to protect workers' health.

This study focuses on the synthesis of zeolites from Pucará clay for the removal of arsenic from groundwater in Chuñuhuayo, Moquegua, Peru. The raw material was initially characterized chemically and physically, determining its silicon dioxide (SiO₂) and aluminum oxide (Al₂O₃) content to predict the type of zeolite that could be obtained. The synthesis was performed via a hydrothermal process, varying temperature, activation time, and NaOH concentration as key factors. The zeolites were evaluated for their cation exchange capacity, with the highest value of 180 meq/100g achieved at 100°C, using 3M NaOH for 8 hours. Morphological and crystalline characterization confirmed the formation of analcime- and phillipsite-type zeolites. Subsequently, these zeolites were applied to groundwater containing 38.4 µg/L of arsenic, significantly exceeding the 10 µg/L limit established by the WHO. Adsorption tests in batch systems demonstrated an arsenic removal efficiency of 96.9% within 50 minutes of contact under magnetic stirring conditions. These findings underscore the potential of zeolites synthesized from local clays as low-cost, efficient materials for arsenic remediation in contaminated groundwater

The following research aims to improve the properties of biodegradable active films based on mango seed starch by incorporating biosynthesized silver nanoparticles. Silver nanoparticles were manufactured by green route from grape residues and were added in the film gelatinization process at concentrations of 3% and 6% v/v and compared with control films (0%). The silver nanoparticles were characterized by UV-Vis spectroscopy and DLS analysis to determine the size distribution profile. Films morphology was analyzed by SEM and the integration of silver nanoparticles in biodegradable films was confirmed by EDS analysis. Thermic stability was studied by TGA curves, mechanical properties and antibacterial activity were also studied. The increase in the percentage of silver nanoparticles produces an improvement in its mechanical properties, also, TGA analysis shows an improvement on thermal stability attributed to the good integration of the nanoparticles in the polymeric matrix. Furthermore, films exhibited antimicrobial activity against E. coli and S. aureus bacteria and C. albicans fungi.