Particles light

Smoke detection depending upon absorption of ionizing radiation by smoke particles light scattering by smoke particles light obscuration. 

Einstein s explanation of the photoelectric effect showed that light has some properties of particles. Light consists of photons, each of which is like a bullet of energy with the discrete energy E = Hy. Although simple, this... 

In a separate study ( ) aerosol species mass distributions were successfully used to calculate the contribution of each species to the extinction coefficient. Unfortunately, such detailed data is not usually available. At most air monitoring stations, only the total aerosol species mass concentrations, M -, are determined from filter samples. Statistical methods have been used to infer chemical species contributions to the particle light extinction coefficient ( ). For such analyses it is assumed that bgp can be represented as a linear combination of the total species mass concentrations, M-j, viz.. 

These limitations on the statistical inference of species contributions to the particle light extinction coefficient raise several questions (i) Is the statistical analysis of filter data a valid method for determining species contributions to the extinction coefficient of atmospheric aerosols (ii) Can we place confidence limits on the quality of the statistical results and (iii) Can the quality of the statistical results be enhanced through improved sampling techniques ... 

The particle light scattering coefficient has been continuously measured at this location since 1976. Measurements of the particle size distribution have been made daily since 1978, providing the data base necessary to assess the variability of the normalized aerosol volume distribution. 

Aerosol sampling instruments were housed in an air conditioned monitoring trailer operated by NWC. The particle light scattering coefficient, bg, was continuously measured with modified MRI Model 1561 integrating nephelometer. The nephelometer automatically zeroed daily and was calibrated quarterly. 

The response R of a single-particle light scattering instrument is... 

Multi-elemental analysis by non-destructive X-ray fluorescence (XRF) is possible on filter tape samples similar to those collected for particle light absorption measurements. Up to 23 elements with the atomic number of potassium and above can be analysed by this method simultaneously, with a time resolution down to 15 min. 

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