@article{_39, author = {[null]}, title = {}, publisher = {Journal of Yangtze River Scientific Research Institute}, year = {2013}, journal = {Journal of Yangtze River Scientific Research Institute}, volume = {30}, number = {12}, eid = {39}, pages = {39-42}, keywords = {}, doi = http://ckyyb.crsri.cn/EN/10.3969/j.issn.1001-5485.2013.12.007 }