Aerosol Dynamics Inc.

Virginia Tech Intellectual Properties, Inc.

Nathan Michael Kreisberg

Susanne Vera Hering

Steven Russel Spielman

Gregory Stephen Lewis

Gabriel Isaacman-VanWertz

A method and apparatus for evaluating the chemical composition of airborne particles by sequentially collecting and analyzing airborne particles in-situ. The method includes: collecting particles; enlarging the particles through water condensation; accelerating the enlarged particles onto a surface to collect enlarged particles; and analyzing the enlarged particles by: isolating the surface; passing a carrier gas over the surface; heating the surface to thermally desorb collected particles into the carrier gas; transporting this evolved vapor into detectors; and assaying the evolved vapor as a function of a desorption temperature. The apparatus includes: a sample flow inlet; a condensational growth tube; a collection and thermal desorption (CTD) cell; a carrier gas source; a heater coupled to the CTD; one or more gas detectors; and a controller configured to operate valves, the heater, the growth tube, and the CTD cell in at least an in-situ sequential collection mode and analysis mode.

Volatility-resolved chemical characterization of airborne particles

A system and method for particle enlargement with continuously wetted wicks includes a container into which a flow of particle-laden air is introduced in a laminar manner through an inlet and to an outlet. The container has a first section, a second section and a third section though which the particle-laden air flows between the inlet and the outlet. The temperature of the second section is warmer than that of the first section at the inlet and the third section at the outlet. In one embodiment, a continuous wick spanning an interior wall of the first second, second section and third section, said wick being capable of internally transporting liquid water along its length is provided.

Wick wetting for water condensation systems

A particle microtrap screen apparatus has an inlet, a jet orifice screen with multiple microjet orifices, and a microtrap plate having multiple microtraps spaced opposite the multiple microjet orifices for entrapping particles entrained by the jets and then released by the gas, and impacting in the microtraps with the energy imparted by the gas as the gas turns and flows between the jet orifice screen and the microtrap impact plate. Collection efficiencies of greater than 90% of particles, about 2 micrometers or larger in size, are experienced with pressure drops of less than 5 millimeters of water. The pressure drop does not increase upon increased loading with particles. The jet orifices have widths of D, about 0.5 millimeters, with spacing between orifices of about 5D and trap width and depth of about 4D and 2D, respectively, with about 2D spacing between the jet orifice screen and the microtrap plate. Ultraviolet lamps in a plenum on the inlet side of the jet orifice screen illuminate the particle traps through the jet orifices for sterilizing microorganisms within the particle traps. The jet orifices are circular or rectangular orifices.

Growing community of inventors

Richmond, CA, United States of America

Nathan Michael Kreisberg