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Rapid Scan Dynamic Humidity Particle Spectrometer

Award Information
Agency: Department of Energy
Branch: N/A
Contract: DE-FG02-11ER86479
Agency Tracking Number: 97337
Amount: $99,989.00
Phase: Phase I
Program: STTR
Solicitation Topic Code: 31 e
Solicitation Number: DE-FOA-0000413
Solicitation Year: 2011
Award Year: 2011
Award Start Date (Proposal Award Date): 2011-06-17
Award End Date (Contract End Date): 2012-05-16
Small Business Information
2545 Central Avenue
Boulder, CO 80301-2865
United States
DUNS: 786731802
HUBZone Owned: No
Woman Owned: No
Socially and Economically Disadvantaged: No
Principal Investigator
 Gregory Kok
 (303) 440-5576
Business Contact
 Gregory Kok
Title: Dr.
Phone: (303) 440-5576
Research Institution
 Georgia Institute of Technology
311 Ferst Drive
Atlanta, GA 30332-0420
United States

 () -
 Nonprofit College or University

The Continuous-Flow Streamwise Thermal-Gradient CCN Counter (CFSTGC) ommercialized by Droplet Measurement Technologies has proven to be reliable, robust, and relatively simple to operate for ground-based and airborne measurements. Supersaturation changes are made by varying the temperature gradient between the top and bottom of the column. This provides a reliable supersaturation, but changing supersaturation requires 30-60 seconds, and the data is not valid during this time. A new mode of CCN instrument operation, called Scanning Flow CCN Analysis, or, SFCA addresses these issues. SFCA involves changing the flow rate in the instrument over time, while maintaining a constant temperature gradient; this causes supersaturation to continuously change, allowing the measurement of a supersaturation spectrum over a flow cycle, which can be as short as 10 seconds and without loss of data continuity. The CCN column can also be used as a subsaturated hygroscopic growth chamber by applying a reverse temperature gradient on the column. Very few instruments to date can operate at these high RH levels, which are crucial for understanding the water uptake properties of aerosol during their transition from cloud-free to cloudy conditions. In this proposal, the SFCA and subsaturated operational modes of the CCN will be expanded to improve the particle counting capability with a more sensitive optical particle counter. Software will also be developed to simplify the data analysis

* Information listed above is at the time of submission. *

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