This study evaluates alternatives using the analytic hierarchy process (AHP) and Fuzzy AHP (FAHP) methodologies across five scenarios (SC1 to SC5), aiming to compare the effectiveness of both approaches in integrating environmental and technical criteria. The results indicate that, in SC1, AHP assigns weights of 14.35% to A1 and 16.22% to A2, while FAHP demonstrates greater dispersion, highlighting A6 with 35.22%. In SC2, AHP prioritizes A1 with 14.16%, whereas FAHP increases the weight of the environmental criterion to 21.18%. In SC3, A1 remains the preferred option in both methodologies, with close weights of 34.00% for AHP and 32.98% for FAHP. In SC4, both methods show similar trends, with A1 standing out at 11.12% and A4 at 34.87%. Finally, in SC5, AHP allocates 8.52% to A1, while FAHP evaluates it at 10.73%. The findings suggest that FAHP allows greater sensitivity to variations in sub‐criteria, enabling a more precise evaluation aligned with sustainability objectives. The significance of environmental and social criteria across the scenarios underscores the necessity of incorporating more sustainable approaches into decision‐making processes. It is concluded that, while AHP delivers consistent results, FAHP may be better suited for contexts characterized by complexity and uncertainty. Furthermore, sensitivity analysis is recommended to examine how variations in criterion weights impact final decisions.
This study performs a systematic review and analysis of research on the use of multicriteria decision analysis (MCDA) methods for more than 45 years. More than 34,468 documents related to MCDA were identified in more than 130 countries, with an annual increase of 14.15% in scientific production. India, China, and Iran lead in number of publications, covering about 35%. The universities with the most publications include Islamic Azad University and Vilnius Gediminas Technical University. The main journals in this field are Expert Systems With Applications, Sustainability, and Journal of Cleaner Production. The most prolific authors are Zavadskas, E.; Wang, J.; Tzeng, GH; Zavadskas, EK; and Kahraman, C. The most popular methods are TOPSIS, AHP (analytic hierarchy process), VIKOR, PROMETHEE (Preference Ranking Organization Method for Enrichment Evaluation), and ANP. LATAN, which includes countries such as Brazil, Chile, and Mexico, has increased the use of MCDA in recent years. Colombia has also shown a great interest in MCDA, especially in the selection of alternative energy sources and industrial suppliers. This method of literature review provides a comprehensive overview of research at MCDA and offers valuable information for future projects and studies.
This study explores a sustainable approach to developing magnetic nanocomposites by synthesizing a mixed-phase iron oxide (IO) and recycled polyamide (RPA) composite from textile waste. The RPA/IO nanocomposite’s microstructural and magnetic properties were characterized using X-ray diffraction (XRD) with Rietveld refinement, scanning, transmission electron microscopy (SEM, TEM), and vibrating sample magnetometry (VSM). The proportions of the Fe3O4 and γ-Fe2O3 phases were found to be 23.2 wt% and 76.8 wt%, respectively. SEM and TEM showed a porous, agglomerated IO surface morphology with an average particle size of 14 nm. Magnetic analysis revealed ferrimagnetic and superparamagnetic behavior, with VSM showing saturation magnetization values of 21.81 emu g−1 at 5 K and 18.84 emu g−1 at 300 K. Anisotropy constants were estimated at 4.28 × 105 and 1.53 × 105, respectively, for IO and the composite, with a blocking temperature of approximately 178 K at 300 K. These results contribute to understanding the magnetic behavior of IO and their nanocomposites, which is crucial for their potential applications in emerging technologies.
In this study, we combine computational and experimental methods to investigate urea-derived (CN-U) and thiourea-derived (CN-TU) graphitic carbon nitride (g-C3N4) for surface adsorption, photocatalytic activity, and cell viability using methylene blue (MB) dye degradation. XRD revealed CN-TU is more ordered (d002 = 0.324 nm; crystallite size = 45.4 nm), while CN-U is less crystalline (d002 = 0.326 nm; 18.1 nm). A precursor-dependent shift in absorption edge showed CN-U with wider indirect bandgap (3.07 eV) compared to CN-TU (2.85 eV). Isotherm models and computational analysis reveal monolayer adsorption governed by van der Waals interactions between MB aromatic hydrogens and nitrogen atoms at g-C3N4 inner edges, with experimental data matching computational predictions. A photocatalytic mechanism was proposed based on band-edge analysis, redox potentials, and electron paramagnetic resonance (EPR)-based ROS quantification. Both samples generated • OH, O2•– , and 1O2 under irradiation. Band-edge analysis (ECB /E VB = -1.84/1.24 eV for CN-U; -1.73/1.12 40 eV for CN-TU) supports thermodynamically favorable O2 reduction to O2•– but disfavors direct • OH formation. Spin-trapping EPR confirmed O2•– as predominant ROS (≈53%), 42 with detectable • OH and 1O2. CN-U showed superior performance due to enhanced O2 •– generation. In vitro cytotoxicity by MTT assay in human MRC-5 fibroblasts (20–100 µM, 72 h) indicated significant viability reductions for both materials, with higher cytotoxicity for CN-TU. ADMET analysis showed heptazine polymerization reduces acute toxicity and increases biological adsorption, while increasing bioaccumulation potential. These results demonstrate that precursor selection enables tuning the adsorption–ROS–photocatalysis–cytotoxicity balance in g-C3N4 , advancing rational development of safer, efficient photocatalysts.
19 May 2026 in Sustainable Materials and Technologies