Title: Detection near 1-nm with a laminar-flow, water-based condensation particle counter

Abstract

Presented is a laminar-flow, water-based condensation particle counter capable of particle detection near 1 nm. This instrument employs a three-stage, laminar-flow growth tube with a “moderator” stage that reduces the temperature and water content of the output flow without reducing the peak supersaturation, and makes feasible operation at the large temperature differences necessary for achieving high supersaturations. The instrument has an aerosol flow of 0.3 L/min, and does not use a filtered sheath flow. It is referred to as a “versatile” water condensation particle counter, or vWCPC, as operating temperatures can be adjusted in accordance with the cut-point desired. When operated with wall temperatures of ~2°C, >90°C, and ~22°C for the three stages, respectively, the vWCPC detects particles generated from a heated nichrome wire with a 50% efficiency cut-point near 1.6 nm mobility diameter. At these operating temperatures, it also detects 10–20% of large molecular ions formed from passing filtered ambient air through a bipolar ion source. Decreasing the temperature difference between the first two stages, with the first and second stages operated at 10 and 90°C, respectively, essentially eliminates the response to charger ions, and raises the 50% efficiency cut-point for the nichrome wire particles to 1.9 nm mobilitymore » diameter. Here, the time response, as measured by rapid removal of an inlet filter, yields a characteristic time constant of 195 ms.« less

Authors:

Hering, Susanne V. ^[1]; Lewis, Gregory S. ^[1]; Spielman, Steven R. ^[1]; Eiguren-Fernandez, Arantzazu ^[1]; Kreisberg, Nathan M. ^[1]; Kuang, Chongai ^[2]; Attoui, Michel ^[3]

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+ Show Author Affiliations

1. Aerosol Dynamics Inc., Berkeley, CA (United States)
2. Brookhaven National Lab. (BNL), Upton, NY (United States)
3. Lisa Univ. Paris Est Creteil, Paris (France)

Publication Date:

Fri Nov 18 00:00:00 EST 2016

Research Org.:

Brookhaven National Laboratory (BNL), Upton, NY (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Biological and Environmental Research (BER)

OSTI Identifier:

1350916

Report Number(s):

BNL-113749-2017-JA
Journal ID: ISSN 0278-6826; R&D Project: 2016-BNL-EE630EECA-Budg; KP1701000

Grant/Contract Number:  

SC00112704

Resource Type:

Accepted Manuscript

Journal Name:

Aerosol Science and Technology

Additional Journal Information:

Journal Volume: 51; Journal Issue: 3; Journal ID: ISSN 0278-6826

Publisher:

American Association for Aerosol Research

Country of Publication:

United States

Language:

English

Subject:

54 ENVIRONMENTAL SCIENCES; nanoparticles; condensation particle counting; growth tube