sentences:  Qualitatively, the aerosols appear dense with a moderately narrow particle size distribution.The method of thermospray ionization was first introduced by a patent evidenced as early as 1983, and described in further detail by a patent published on March 8, 1988.Inventors Marvin L. Vestal and Calvin R. Blakley proposed an ion vapor source for mass spectrometry of liquids under a US Grant from the Department of Health, Education, and Welfare.