Patents by Inventor Ping-Xiao Guan

Ping-Xiao Guan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Methods for making controlled-release ammonium phosphate fertilizer
    Patent number: 7252697
    Abstract: A method for making controlled-release ammonium phosphate fertilizer has the following acts of: cracking, pulverizing, blending, aging, drying, and adding release-controlling materials into an ammonium phosphate slurry during preparing processes or adding release-controlling materials in achieved ammonium phosphate powder. Selectively, sulfuric acid is added into the mixture of the release-controlling materials and the ammonium phosphate slurry or ammonium phosphate powder to acidify the mixture. In this method, the release-controlling material combines with the ammonium phosphate by chemical bonding to control the release of nitrogen and phosphorus nutrients to enhance the use efficiency and elongate fertilization effect of the controlled-release ammonium phosphate fertilizer.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: August 7, 2007
    Assignee: South China Agricultural University
    Inventors: Zongwen Liao, Song Bo, Xiaoyun Mao, Ping-Xiao Guan
  • Methods for making controlled-release ammonium phosphate fertilizer
    Publication number: 20040003636
    Abstract: A method for making controlled-release ammonium phosphate fertilizer has the following acts of: cracking, pulverizing, blending, aging, drying, and adding release-controlling materials into an ammonium phosphate slurry during preparing processes or adding release-controlling materials in achieved ammonium phosphate powder. Selectively, sulfuric acid is added into the mixture of the release-controlling materials and the ammonium phosphate slurry or ammonium phosphate powder to acidify the mixture. In this method, the release-controlling material combines with the ammonium phosphate by chemical bonding to controll the release of nitrogen and phosphorus nutrients to enhance the use efficiency and elongate fertilization effect of the controlled-release ammonium phosphate fertilizer.
    Type: Application
    Filed: July 2, 2003
    Publication date: January 8, 2004
    Inventors: Zongwen Liao, Song Bo, Xiaoyun Mao, Ping-Xiao Guan