Leaching of a low-grade lead and zinc oxide ore was studied by an organic reagent, citric acid. The quadratic mathematical models were developed for the relationship among the influential parameters and lead and zinc recoveries. Leaching rate was strongly affected by the interactive effects of factors. It was also found that the quadratic effects of stirring speed and linear<e...

The software manual of a MATLAB 6.0 implementation of the LSTRS method is presented. LSTRS was described in M. Rojas, S.A. Santos and D.C. Sorensen, A new matrix-free method for the large-scale trust-region subproblem, SIAM J. Optim., 11(3):611-646, 2000. LSTRS is designed for large-scale quadratic problems with one norm constraint. The method is based on a reformulation of the trust-region sub...