Polar Imaging Nephelometer

High-end instrument for precise particle characterization

The PI Neph (Polar Imaging Nephelometer) is a high grade laboratory instrument designed for an in-depth understating of particulate properties. It provides a full particle characterization including the size distribution and the complex refractive index from hyperangle scattering measurements. Amongst its capabilities, the PI-Neph includes: measuring light scattering from 3° to 176°, angular resolution of less than 1°, standard configuration of 2 wavelengths but customizable for 1-3 wavelengths, polarization and a GRASP™ included software package.

GRASP software included package contributes to the retrieval of parameters such as size distribution, percent sphericity or complex refractive index. In addition, it can provide an overview of the multi-source retrieval capabilities of the algorithm and suggest exploring further analysis. The fact that the PI Nephelometer brings so much capabilities also makes it more complex to use. In this regard, the learning curve to get to most of his capabilities are accompanied with an extensive instruments training. In sum, the instrument will not only provide a deeper understanding on particulate matter but also will introduce trainees to GRASP software capabilities.

Data sheet

  • Operational temperature: 5 to 40℃
  • Wavelengths: Up to 3 in the range of 400-680 nm
  • Polarization: P11 and P12 measurements. Other stokes parameters options available
  • Angular Range: At least 100 angles from 5-175°
  • Range: 0.0 to >20000 Mm-1
  • Lower detectable limit: < 1 Mm –1 for phase function measurements
  • Programmable flow rate: Available
  • Flow range: 2 to 20 lpm & Optional
  • Particle size selection: Optional cycling up to 4 cut off sizes
  • External pump option: Available
  • Automatic Zero and Span check: Automatic Zero with clean air system. GRASP software. Included for span calibration
  • Light source: Laser
  • Dimensions: 200*100*50cm
  • Weight: < 30 Kg
  • Storage memory: Internal SSD hard drive
  • Data Transfer: USB, Ethernet, wifi
  • Environmentally rugged: For Indoor or Aircraft Use

The PI Neph can provide size distribution retrieval, determine sphericity, measure complex refractive index and determine full particule characterization from hyper-angle scattering measurements. Also, it can measure scattering light (3°-176°) and has an angular resolution of <1°. The standard configuration is 2 visible wavelengths, customizable for 1-3 wavelengths. The GRASP™ software analaysis package is also included.

We suggest the Polar Imaging Nephelometer for specific scientific research purposes looking for in depth and advanced characterization of particulate properties in laboratory or aircraft settings.

Retrievals of aerosol size distribution,spherical fraction, and complex refractive index from airborne in situ angular light scattering and absorption measurements. Espinosa, W. R., Vanderlei Martins, J.,Remer, L. A., Dubovik, O.,Lapyonok, T., Fuertes, D., et al. (2019). Journal of Geophysical Research: Atmospheres,124,7997–8024. https://doi.org/10.1029/2018JD030009

Investigating biomass burning aerosol morphology using a laser imaging nephelometer. Manfred, K. M., Washenfelder, R. A., Wagner, N. L., Adler, G., Erdesz, F., Womack, C. C., Lamb, K. D. Schwarz, J. P., Franchin, A., Selimovic, V., Yokelson, R. J., and Murphy, D. M. (2018) Atmos. Chem. Phys., 18, 1879-1894, https://doi.org/10.5194/acp-18-1879-2018

Retrievals of aerosol optical and microphysical properties from imaging polar nephelometer scattering measurements. W. R. Espinosa., Remer, L. A., Dubovik, O., Ziemba, L., Beyersdorf, et. al. (2017). Atmospheric Measurement Techniques, 10(3), 811-824. http://dx.doi.org/10.5194/amt-10-811-2017; https://www.atmos-meas-tech.net/10/811/2017/

In situ measurements of angular dependent light scattering by aerosols over the contiguous United States. W. R Espinosa, J. Vanderlei Martins, Lorraine A. Remer et.al. (2017) Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2017-941; https://www.atmos-chem-phys-discuss.net/acp-2017-941/acp-2017-941.pdf

Espinosa, W. R. (2017). Comprehensive airborne in situ characterization of atmospheric aerosols: From angular light scattering to particle microphysics (Order No. 10639352). Available from Dissertations & Theses @UMBC; ProQuest Dissertations & Theses Global. (1984589840). http://proxy-bc.researchport.umd.edu/login?url=; https://search.proquest.com/docview/1984589840?accountid=14577