SHNAIHEJ, K. T. .; KHALEEL, S. F. .; SUKKAR, D. K. A. . Preparation of Nano Silica particles by laboratory from Iraqi sand and added it to concrete to improve hardness specifications. Journal of Petroleum Research and Studies, [S. l.], v. 9, n. 3, p. 36-58, 2019. DOI: 10.52716/jprs.v9i3.313. Disponível em: https://jprs.gov.iq/index.php/jprs/article/view/313. Acesso em: 2 jul. 2022.