Aerosol Dynamics, Inc. | Date: 2014-06-27
This technology relates to the enlargement by water condensation in a laminar flow of airborne particles with diameters of the order of a few nanometers to hundreds of nanometers to form droplets with diameters of the order of several micrometers. The technology presents several advanced designs, including the use of double-stage condensers. It has application to measuring the number concentration of particles suspended in air or other gas, to collecting these particles, or to focusing these particles.
Aerosol Dynamics, Inc. | Date: 2010-10-22
Technology is presented for the high efficiency concentration of fine and ultrafine airborne particles into a small fraction of the sampled airflow by condensational enlargement, aerodynamic focusing and flow separation. A nozzle concentrator structure including an acceleration nozzle with a flow extraction structure may be coupled to a containment vessel. The containment vessel may include a water condensation growth tube to facilitate the concentration of ultrafine particles. The containment vessel may further include a separate carrier flow introduced at the center of the sampled flow, upstream of the acceleration nozzle of the nozzle concentrator to facilitate the separation of particle and vapor constituents.
Brookhaven Science Associates LLC and Aerosol Dynamics, Inc. | Date: 2013-10-08
A parallel plate dimensional electrical mobility separator and laminar flow water condensation provide rapid, mobility-based particle sizing at concentrations typical of the remote atmosphere. Particles are separated spatially within the electrical mobility separator, enlarged through water condensation, and imaged onto a CCD array. The mobility separation distributes particles in accordance with their size. The condensation enlarges size-separated particles by water condensation while they are still within the gap of the mobility drift tube. Once enlarged the particles are illuminated by a laser. At a pre-selected frequency, typically 10 Hz, the position of all of the individual particles illuminated by the laser are captured by CCD camera. This instantly records the particle number concentration at each position. Because the position is directly related to the particle size (or mobility), the particle size spectra is derived from the images recorded by the CCD.
Agency: Department of Energy | Branch: | Program: STTR | Phase: Phase II | Award Amount: 1.39M | Year: 2015
Organic chemicals comprise the dominant fraction of particulates found in atmospheric aerosols, and the largest proportions of these are secondary products formed in the atmosphere from oxidation of volatile organic compounds. Often these chemical transformations result from complex pathways involving species from different sources. To understand these processes, we need to be able to trace the transformation pathways from the emitted vapor species to the oxygenated, less volatile organic matter that comprises the organic aerosol. Proposed is expanding the capability of the Semi-Volatile Thermal desorption Aerosol Gas chromatograph (SV-TAG) instrument to add the measurement of more volatile VOCs which are important secondary organic aerosol (SOA) precursors. Both the VOC precursor and resulting SOA products will be measured by a single detector providing consistent quantification over 15 orders of magnitude of volatility in the comprehensive TAG (c-TAG) instrument. Phase I work developed a VOC collector compatible with the existing SV-TAG system and capable of measuring, identifying, and quantifying organic compounds within the volatility range equal to that of C5 to C16 alkanes. This range spans the dominant biogenic emissions of isoprene and monoterpenes, as well as many important anthropogenic alkanes and aromatics from fossil fuel use. In our Phase II effort we aim to combine these VOC and SVOC channels into a single instrument with a common mass spectrometer, to provide a fully automated, field-deployable instrument with on-line calibration. The proposed instrument will be the very first to comprehensively measure C5- C33 species hourly in-situ, including essentially all the major known primary precursors to secondary organic aerosols from biogenic and anthropogenic sources, along with many of their oxidation products. Combining these measurements in the proposed single comprehensive c-TAG instrument offers many compelling, practical advantages, including consistency through use of a common detector, lower costs, and a smaller footprint. Commercial Applications and Other Benefits: This instrument will be of practical use to the atmospheric research community, especially those now using aerosol mass spectrometers to measure bulk aerosol composition. The molecular level speciation from this instrument will provide insights into chemical transformation processes in the atmosphere that are important to particle formation, and indirectly to cloud characteristics and climate.
Aerosol Dynamics, Inc. | Date: 2013-10-01
A particle charging method and apparatus are provided. An ion source is applied to a particle laden flow. The flow is introduced into a container in a laminar manner. The container has at least a first section, a second section and a third section. The first section includes wetted walls at a first temperature. A second section adjacent to the first section has wetted walls at a second temperature T