The Effect of Nanoparticle Morphology on the Measurement Accuracy of Mobility Particle Sizers

Awasthi, Amit; Wu, Bo-Sen; Liu, Chun Nan; Chen, Chun Wan; Uang, Shi Nan; Tsai, Chuen-Tinn

doi:10.1007/s12647-013-0068-7

Cited by 13 publications

(11 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, as reported previously, the FMPS is unable to properly measure the monodisperse distributions that the PSL should give rise to due to its data inversion where the measured particles always will be spread out over a minimum of five channels (TSI 2011;Leskinen et al 2012;Awasthi et al 2013). The CPC 3010 and CPC 3007 were also compared in terms of concentration to be within the manufacture-stated precision.…”

Section: Condensation Particle Counter (Cpc 3007 Tsi)mentioning

confidence: 99%

“…They found low deviation for the FMPSs from the GMD ( §7.5%) as measured by the SMPS systems. Awasthi et al (2013) compared the Engine Exhaust Particle Size (EEPS 3090; TSI Inc., Shoreview, MN, USA), which uses the same measurement design as the FMPS, with an SMPS for silver agglomerates, and showed that the EEPS consistently measured smaller number median mobility diameters and overestimated the total number concentration up to 67%. They also concluded that for small monodisperse particles (<80 nm), the EEPS measured diameters close to that of the SMPS but with a polydispersive distribution.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Limitations in the Use of Unipolar Charging for Electrical Mobility Sizing Instruments: A Study of the Fast Mobility Particle Sizer

Levin

Gudmundsson

Pagels

et al. 2015

Aerosol Science and Technology

View full text Add to dashboard Cite

A comparison between three different types of particle sizing instruments (fast mobility particle sizer, FMPS; electrical low pressure impactor, ELPI; and scanning mobility particle sizer, SMPS) and one condensation particle counter (CPC) was made to compare instrument response in terms of size distributions and number concentration. Spherical oil droplets in 39 different sizes, with geometric mean diameter (GMD) ranging from 50 nm to 820 nm, were used as test particles. Furthermore, a characterization of the FMPS unipolar charger behavior was made to analyze the measured size distributions and number concentrations. The results show that all three sizing-instruments agree well for particle sizes below 200 nm, both in terms of size and number concentration, but the FMPS deviates clearly when particle sizes exceed 200 nm. Above this, the FMPS underestimates the particle size throughout the remainder of the size range, with an apparent upper limit for GMD of 300 nm. It also estimates a higher particle number concentration as compared to the other instruments. Analysis of the 22 FMPS electrometer currents and calculation of average number of charges per particle show a diameter dependence of response of d 1:21 p for the FMPS unipolar charger. The resulting calculated electrical mobility showed a minimum in mobility for spherical particles at 577 nm, which indicates an interfering range of particles above the measurement range, but below the cut-off of the inlet pre-separator (1 mm). The study concludes that particle distributions with a true GMD above 200 nm cannot be measured reliably with the FMPS.

show abstract

Section: Condensation Particle Counter (Cpc 3007 Tsi)mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Limitations in the Use of Unipolar Charging for Electrical Mobility Sizing Instruments: A Study of the Fast Mobility Particle Sizer

Levin

Gudmundsson

Pagels

et al. 2015

Aerosol Science and Technology

View full text Add to dashboard Cite

show abstract

“…Two commonly applied instruments capable of high time resolution particle number and size characterization are the TSI Fast Mobility Particle Sizer (FMPS) and the Engine Exhaust Particle Sizer (EEPS). When measuring traffic-related particle sources in parallel, agreement between the SMPS, the FMPS, and the EEPS has been inconsistent (Asbach et al, 2009;Awasthi et al, 2013;Kaminski et al, 2013;Leskinen et al, 2012).…”

Section: Introductionmentioning

confidence: 99%

A source-independent empirical correction procedure for the fast mobility and engine exhaust particle sizers

Zimmerman

Jeong

Wang

et al. 2015

Atmospheric Environment

View full text Add to dashboard Cite

h i g h l i g h t sAccuracy of high time resolution particle sizers is affected by particle morphology. These instruments also under-size particles larger than 80 nm. We provide a source-independent correction protocol to address this issue. The correction protocol ensures agreement within 20% of a reference instrument. Keywords: EEPS FMPS SMPS Morphology Vehicle emissions Particle size distributions a b s t r a c tThe TSI Fast Mobility Particle Sizer (FMPS) and Engine Exhaust Particle Sizer (EEPS) provide size distributions for 6e560 nm particles with a time resolution suitable for characterizing transient particle sources; however, the accuracy of these instruments can be source dependent, due to influences of particle morphology. The aim of this study was to develop a source-independent correction protocol for the FMPS and EEPS. The correction protocol consists of: (1) broadening the >80 nm size range of the distribution to account for under-sizing by the FMPS and EEPS; (2) applying an existing correction protocol in the 8e93 nm size range; and (3) dividing each size bin by the ratio of total concentration measured by the FMPS or EEPS and a water-based Condensation Particle Counter (CPC) as a surrogate scaling factor to account for particle morphology. Efficacy of the correction protocol was assessed for three sources: urban ambient air, diluted gasoline direct injection engine exhaust, and diluted diesel engine exhaust. Linear regression against a reference instrument, the Scanning Mobility Particle Sizer (SMPS), before and after applying the correction protocol demonstrated that the correction ensured agreement within 20%.

show abstract

“…There have been extensive laboratory and ambient air studies related to particle mass, mass concentration, density, and morphology (McMurry et al 2002;Park et al 2003aPark et al , 2004DeCarlo et al 2004;Geller et al 2006;Virtanen et al 2006;Lall et al 2008;Lee et al 2009;Tsai et al 2009Tsai et al , 2011Chen et al 2010Chen et al , 2013Awasthi et al 2013;Johnson et al 2013;Symonds et al 2013). Two commercially available particle mass analyzers, namely, aerosol particle mass analyzer (APM) (Ehara et al , 1996 and Couette centrifugal particle mass analyzer (CPMA) (Olfert and Collings 2005;Olfert et al 2006) were often used in these studies.…”

Section: Introductionmentioning

confidence: 99%

The Effect of Nanoparticle Convection-Diffusion Loss on the Transfer Function of an Aerosol Particle Mass Analyzer

Lin

Liao

Tzeng

et al. 2014

Aerosol Science and Technology

Self Cite

View full text Add to dashboard Cite

The existing theoretical response spectra of APM-3600 agree well with the experimental data for submicron particles larger than 100 nm in the electrical mobility diameter but not for nanoparticles. In this study, a 2-D numerical model was developed to predict the transfer function and response spectra of APM-3600 based on the detailed simulation of flow and particle concentration fields. It was found that recirculation flows existed in the annular classifying region and APM's inlet and outlet regions, which led to enhanced convection-diffusion loss of nanoparticles compared to that without considering flow recirculation. As a result, the APM underestimates the mass of naonoparticles due to the shift of the peak position of the transfer function to a larger diameter than the targeted diameter. The response spectra calculated with the simulated transfer function agree well both in shapes and peak values with the experimental data present in a previous study for both nanoparticles and submicron particles larger than 100 nm. The predicted particle masses also agree well with the PSL's experimental data of the article.

show abstract

The Effect of Nanoparticle Morphology on the Measurement Accuracy of Mobility Particle Sizers

Cited by 13 publications

References 38 publications

Limitations in the Use of Unipolar Charging for Electrical Mobility Sizing Instruments: A Study of the Fast Mobility Particle Sizer

Limitations in the Use of Unipolar Charging for Electrical Mobility Sizing Instruments: A Study of the Fast Mobility Particle Sizer

A source-independent empirical correction procedure for the fast mobility and engine exhaust particle sizers

The Effect of Nanoparticle Convection-Diffusion Loss on the Transfer Function of an Aerosol Particle Mass Analyzer

Contact Info

Product

Resources

About