1. Department of Chemical Engineering and Department of Petroleum Engineering University of Wyoming Laramie WY 82071 USA
2. Faculty of Environmental Science and Engineering Kunming University of Science and Technology Kunming 650500 P. R. China
3. Department of Chemical Engineering Brigham Young University Provo UT 84602 USA
4. Department of Civil Engineering University of Wyoming Laramie WY 82071 USA
5. School of Civil and Environmental Engineering Georgia Institute of Technology Atlanta GA 30332 USA
6. School of Energy Resources University of Wyoming Laramie WY 82071 USA