dos
approximated dos written in "Polymer Engineering and science, 47, 1359(2007)" http://onlinelibrary.wiley.com/doi/10.1002/pen.20820/abstract
approximated dos written in "Polymer Engineering and science, 47, 1359(2007)" http://onlinelibrary.wiley.com/doi/10.1002/pen.20820/abstract