Precipitable Water and the Precipitation Conversion Efficiency in Summer During the Recent 45 Years in Zhengzhou  
LIU Yuanyuan,ZHOU Shunwu,WU Peipei,MA Siqi
Journal of Arid Meteorology . 2013, (3): 486 -490 .  DOI: 10. 11755/j. issn. 1006 -7639(2013) -03 -0486