Removal of cadmium in water samples from the El Macho estuary, Machala-Ecuador, using polyurethane foam activated with silver nanoparticles as an adsorbent. Novasinergia [Internet]. 2024 Jul. 3 [cited 2025 Apr. 1];7(2):36-51. Available from: https://novasinergia.unach.edu.ec/index.php/novasinergia/article/view/446