Patents by Inventor Xuejun Chen

Xuejun Chen 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).

  • Patent number: 7582456
    Abstract: The invention discloses a method for directly separating and purifying polyhydroxyalkanoates in cells from fermentation liquid and it relates to the field of posttreatment technology of biological engineering. The method includes following steps: pretreating fermentation liquid with physical method for breaking cell wall; adjusting pH value of pretreated fermentation liquid to alkaline; adding anionic surfactant; reacting under agitation; separating and extracting coagulated precipitate from reaction liquid; washing and drying. The invention has the advantage of simple technology, low cost, high extraction yield and no pollution, and large scale industrialized production can be realized.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: September 1, 2009
    Assignee: Tianan Biologic Material Co., Ltd. Ningbo
    Inventor: Xuejun Chen
  • Publication number: 20090195317
    Abstract: A power amplifier includes a plurality of amplification paths in which at least one amplification path is selectively enabled and disabled, wherein each amplification path includes an output impedance modification element and an output phase shift element that is operable independently from the output impedance modification element, and wherein the output impedance modification element in each amplification path provides selective impedance for each amplification path.
    Type: Application
    Filed: November 18, 2008
    Publication date: August 6, 2009
    Inventors: Guohao Zhang, Shiaw W. Chang, Xuejun Chen, Jing Sun
  • Publication number: 20070072276
    Abstract: The invention discloses a method for directly separating and purifying polyhydroxyalkanoates in cells from fermentation liquid and it relates to the field of posttreatment technology of biological engineering. The method includes following steps: pretreating fermentation liquid with physical method for breaking cell wall; adjusting pH value of pretreated fermentation liquid to alkaline; adding anionic surfactant; reacting under agitation; separating and extracting coagulated precipitate from reaction liquid; washing and drying. The invention has the advantage of simple technology, low cost, high extraction yield and no pollution, and large scale industrialized production can be realized.
    Type: Application
    Filed: December 19, 2003
    Publication date: March 29, 2007
    Inventor: Xuejun Chen