Patents by Inventor Narayan Pradhan

Narayan Pradhan 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).

  • Doped semiconductor nanocrystals and methods of making same
    Patent number: 8012377
    Abstract: A method of synthesizing doped semiconductor nanocrystals.
    Type: Grant
    Filed: February 4, 2009
    Date of Patent: September 6, 2011
    Assignee: The Board of Trustees of the University of Arkansas
    Inventors: Xiaogang Peng, Narayan Pradhan
  • Multi-dimensional complex nanocrystal structures and methods of making same
    Patent number: 8007757
    Abstract: A method of synthesizing nanostructures. In one embodiment, the method includes the step of heating a reaction mixture at an elevated temperature, T, for a period of time effective to allow the growth of desired nanostructures. The reaction mixture contains an amount, P, of a carboxylate salt and an amount, L, of a fatty acid ligand, defining a molar ratio of the fatty acid ligand to the carboxylate salt, ?=L/P, and a hydrocarbon solvent. The reaction mixture is characterizable with a critical ligand protection, ?, associating with the chemical structure of the carboxylate salt such that when ?<?, the reaction mixture is in a limited ligand protection (LLP) domain, and when ?>?, the reaction mixture is in a sufficient ligand protection (SLP) domain.
    Type: Grant
    Filed: May 17, 2007
    Date of Patent: August 30, 2011
    Assignee: The Board of Trustees of the University of Arkansas
    Inventors: Xiaogang Peng, Arun Narayanaswamy, Narayan Pradhan
  • Transition Metal Ion Doped Semiconductor Nanocrystals and a Process for the Preparation Thereof
    Publication number: 20110186780
    Abstract: The present invention deals with transition metal ions doped semiconductor nanocrystals that are free from heavy metals like cadmium and therefore environment friendly and useful for biological applications. The present invention also describes a process for the preparation of such transition metal ion doped semiconductor nanocrystals, where the reactions take place at a temperature less than 3000 C. The said doped nanocrystals are stable in air and under UV radiation in both solution and precipitated solid form.
    Type: Application
    Filed: August 17, 2009
    Publication date: August 4, 2011
    Applicant: INDIAN ASSOCIATION FOR THE CULTIVATION OF SCIENCE
    Inventors: Narayan Pradhan, Nikhil Ranjan Jana, Dipankar Das Sarma
  • Doped semiconductor nanocrystals and methods of making same
    Patent number: 7632428
    Abstract: A method of synthesizing doped semiconductor nanocrystals.
    Type: Grant
    Filed: April 25, 2006
    Date of Patent: December 15, 2009
    Assignee: The Board of Trustees of the University of Arkansas
    Inventors: Xiaogang Peng, Narayan Pradhan
  • DOPED SEMICONDUCTOR NANOCRYSTALS AND METHODS OF MAKING SAME
    Publication number: 20090302304
    Abstract: A method of synthesizing doped semiconductor nanocrystals.
    Type: Application
    Filed: February 4, 2009
    Publication date: December 10, 2009
    Inventors: Xiaogang Peng, Narayan Pradhan
  • Multi-dimensional complex nanocrystal structures and methods of making same
    Publication number: 20080081016
    Abstract: A method of synthesizing nanostructures. In one embodiment, the method includes the step of heating a reaction mixture at an elevated temperature, T, for a period of time effective to allow the growth of desired nanostructures. The reaction mixture contains an amount, P, of a carboxylate salt and an amount, L, of a fatty acid ligand, defining a molar ratio of the fatty acid ligand to the carboxylate salt, ?=L/P, and a hydrocarbon solvent. The reaction mixture is characterizable with a critical ligand protection, ?, associating with the chemical structure of the carboxylate salt such that when ?<?, the reaction mixture is in a limited ligand protection (LLP) domain, and when ?>?, the reaction mixture is in a sufficient ligand protection (SLP) domain.
    Type: Application
    Filed: May 17, 2007
    Publication date: April 3, 2008
    Applicant: Board of Trustees of the University of Arkansas
    Inventors: Xiaogang Peng, Arun Narayanaswamy, Narayan Pradhan
  • Doped semiconductor nanocrystals and methods of making same
    Publication number: 20070194279
    Abstract: A method of synthesizing doped semiconductor nanocrystals.
    Type: Application
    Filed: April 25, 2006
    Publication date: August 23, 2007
    Applicant: BOARD OF TRUSTEES OF THE UNIVERSITY OF ARKANSAS
    Inventors: Xiaogang Peng, Narayan Pradhan