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Title: 3002 Humidified Tandem Differential Mobility Analyzer Instrument Handbook

Abstract

The Brechtel Manufacturing Inc. (BMI) Humidified Tandem Differential Mobility Analyzer (HT-DMA Model 3002) (Brechtel and Kreidenweis 2000a,b, Henning et al. 2005, Xerxes et al. 2014) measures how aerosol particles of different initial dry sizes grow or shrink when exposed to changing relative humidity (RH) conditions. It uses two different mobility analyzers (DMA) and a humidification system to make the measurements. One DMA selects a narrow size range of dry aerosol particles, which are exposed to varying RH conditions in the humidification system. The second (humidified) DMA scans the particle size distribution output from the humidification system. Scanning a wide range of particle sizes enables the second DMA to measure changes in size or growth factor (growth factor = humidified size/dry size), due to water uptake by the particles. A Condensation Particle Counter (CPC) downstream of the second DMA counts particles as a function of selected size in order to obtain the number size distribution of particles exposed to different RH conditions.

Authors:
 [1]
+ Show Author Affiliations
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
DOE Office of Science Atmospheric Radiation Measurement (ARM) Program (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1251403
Report Number(s):
DOE/SC-ARM-TR-161
DOE Contract Number:
AC05-7601830
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; aerosol particles; particle growth factor; aerosol particle concentration

Citation Formats

Uin, Janek. 3002 Humidified Tandem Differential Mobility Analyzer Instrument Handbook. United States: N. p., 2016. Web. doi:10.2172/1251403.
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Uin, Janek. 3002 Humidified Tandem Differential Mobility Analyzer Instrument Handbook. United States. doi:10.2172/1251403.
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Uin, Janek. Tue . "3002 Humidified Tandem Differential Mobility Analyzer Instrument Handbook". United States. doi:10.2172/1251403. https://www.osti.gov/servlets/purl/1251403.
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@article{osti_1251403,
title = {3002 Humidified Tandem Differential Mobility Analyzer Instrument Handbook},
author = {Uin, Janek},
abstractNote = {The Brechtel Manufacturing Inc. (BMI) Humidified Tandem Differential Mobility Analyzer (HT-DMA Model 3002) (Brechtel and Kreidenweis 2000a,b, Henning et al. 2005, Xerxes et al. 2014) measures how aerosol particles of different initial dry sizes grow or shrink when exposed to changing relative humidity (RH) conditions. It uses two different mobility analyzers (DMA) and a humidification system to make the measurements. One DMA selects a narrow size range of dry aerosol particles, which are exposed to varying RH conditions in the humidification system. The second (humidified) DMA scans the particle size distribution output from the humidification system. Scanning a wide range of particle sizes enables the second DMA to measure changes in size or growth factor (growth factor = humidified size/dry size), due to water uptake by the particles. A Condensation Particle Counter (CPC) downstream of the second DMA counts particles as a function of selected size in order to obtain the number size distribution of particles exposed to different RH conditions.},
doi = {10.2172/1251403},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Mar 01 00:00:00 EST 2016},
month = {Tue Mar 01 00:00:00 EST 2016}
}
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Technical Report:
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DOI:  10.2172/1251403
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