Shnaihej, K. T. ., Khaleel, S. F. ., & Sukkar, D. K. A. . (2019). 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, 9(3), 36-58. https://doi.org/10.52716/jprs.v9i3.313