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Particle Size Analyzers: Practical Procedures and Laboratory Techniques
Published in Christopher S. Cox, Christopher M. Wathes, Bioaerosols Handbook, 2020
Recently, TSI has introduced a modification to the operation of the DMPS so that complete size scans can be achieved in as little as 60 s at very high resolution (64 channels per decade of size). The Scanning Mobility Particle Sizer (SMPS) is based on the work of Wang and Flagan126 in which the electric field strength in the electrical classifier section of the DMPS is varied monotonically, at the same time making particle number concentration measurements in rapid succession (as much as 10 times per second) using a condensation nuclei counter. The measurement cycle consists of repeated ramps of the central electrode voltage on an exponential scale, increasing from a defined minimum value to maximum field strength, then decreasing the field strength back to the minimum value. The particles entering the sample extraction slot of the classifier will have a monotonie variation in electrical mobility if the electric field strength is varied monotonically Hence, after making allowances for the finite transit times of the particles within the classifier and from the extraction slot to the condensation nucleus counter, the entire size distribution of the incoming aerosol can be scanned both accurately and rapidly. The system is designed to be used with the most recently introduced range of condensation nucleus counters that contain the necessary interface electronics.
Material Characterizations
Published in Debasish Sarkar, Nanostructured Ceramics, 2018
Nanoparticles are subject to experience agglomeration of primary particles and often represent as secondary particles which consist of wider size distribution. Thus, particle size distribution encompasses the particle size and volume fraction with a qualitative prediction only, which is confusing, but a quantitative statistical analysis can envisage the monosize, narrow size, or wider size distribution of particles in order to provide an insight for the selection of nanoparticles for particular applications. In a recent article, a statistical analysis technique has been introduced to analyze nanoparticle size distribution phenomenon, which quantifies the real meaning of the nanoparticle size characteristics [22]. Scanning Mobility Particle Sizer (SMPS) spectrometer is widely used as the standard for measuring airborne particle size distributions, as well as particles suspended in liquids [23]. SMPS spectrometer sizing is a discreet technique in which number populations are measured directly without assuming the shape of the particle size distribution. The method is independent of the refractive index of the particle or fluid and has a high degree of absolute sizing accuracy and measurement repeatability. Table 2.4 illustrates how to approach three parameter Weibull statistical analysis for particle size distribution and their quantification parameters from experimental data (x and N). In order to determine the particle volume fraction in percentage, divide all N1, N2, N3……Nn values by the highest particle value (N), and multiply by 100, then plot the particle volume fraction (%) versus particle size (x).
Measurement of Indoor Air Contaminants
Published in Elizabeth L. Anderson, Roy E. Albert, RISK ASSESSMENT and INDOOR AIR QUALITY, 2019
Far more complex particle counters capable of providing data on very finely divided size fractions are beginning to find use in field monitoring indoors. One such monitor is the Aerodynamic Particle Sizer (APS) of TSI, Inc., which returns information on particle numbers in 50 size fractions from about 0.1 μm to about 20 μm, although the range from 0.1 μm to 1 μm is of uncertain validity. A complementary system, returning data on the ultrafine particles from about 0.01 μm to 0.5 μm, is the Scanning Mobility Particle Sizer (SMPS) by the same company. These two devices have been used in research studies of a few residences (Abt Inc., personal communication).
Method to assess performance of scanning mobility particle sizer (SMPS) instruments and software
Published in Aerosol Science and Technology, 2018
Mark R. Stolzenburg, Peter H. McMurry
The Scanning Mobility Particle Sizer (SMPS) (Wang and Flagan 1990) is the most commonly used instrument for measuring size distributions of sub-0.5 µm aerosol particles. However, insufficient attention has been paid to assessing the quality of SMPS data. This is largely because suitable methods have not been developed, accepted, and routinely used by aerosol scientists. In this Letter we describe a method that determines to high accuracy whether or not the SMPS mobility classifier, condensation particle counter, and data acquisition/analysis software are performing properly.
Characterization of in-stack particulate emissions from residential wood hydronic heater appliances under different combustion conditions
Published in Journal of the Air & Waste Management Association, 2022
Jake Lindberg, Nicole Vitillo, Marilyn Wurth, Brian P. Frank, Shida Tang, Gil LaDuke, Patricia Mason Fritz, Rebecca Trojanowski, Thomas Butcher
The SMPS is a scanning mobility particle sizer, which can measure the concentration of particles with electrodynamic diameters between 10 and 420 nm. The SMPS was operated using an aerosol inlet flow rate of 0.75 LPM and working fluid of 99.5+% pure spectroscopic grade isopropyl alcohol in scanning mode. Size-segregated particle concentrations were collected continuously on a 1-min time basis throughout each experiment.