Retraction：Study on the influence of cyclone convex structure on copper separation. International Journal of Mechanical and Electrical Engineering, London, U.K., v. 1, n. 1, p. 79–92, 2023. DOI: 10.62051/ijmee.v1n1.09. Disponível em: https://wepub.org/index.php/IJMEE/article/view/587. Acesso em: 29 apr. 2026.