Corresponding author at: P.O. Box 303 of China Agricultural University, Qinghua East Road No. 17, Haidian District, Beijing 100083,China. Tel.: +86 10 62737645; fax: +86 10 62737434x601.
E-mail address: wzhfuwzhfu@163.com (Z.F. Wang).
Received 7 June 2011; Received in revised form 26 September 2011; Accepted 12 October 2011
0960-3085/$ – see front matter © 2011 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
doi:10.1016/j.fbp.2011.10.003