Acidity measurement of iron ore powders using laser-induced breakdown spectroscopy with partial least squares regression Hao, Z. Q. ; Li, C. M. ; Shen, M. ; Yang, X. Y. ; Li, K. H. ; Guo, L. B. ; Li, X. Y. ; Lu, Y. F. ; Zeng, X. Y. Abstract Publication: Optics Express Pub Date: March 2015 DOI: 10.1364/OE.23.007795 Bibcode: 2015OExpr..23.7795H