Source resolution

Hopke, P.K. The Application of Factor Analysis to Urban Aerosol Source Resolution, ACS SYMPOSIUM SERIES, No. 167, 1981. 

We start from the chemical element balance (CEB) method Z) of source resolution as a reference approach although it is not necessary to all of the discussion which follows. 

BeP was assumed a stable species in the source resolution analysis. 

Finally, receptor modeling offers a useful theme around which to organize aerosol characterization studies. Large scale field studies are expensive, and they also tend to be diffuse. Data requirements for source resolution can be used to select the chemical and physical properties of the aerosol to be measured both at receptor sites and at sources. 

Duval, M.M., (1980) "Source Resolution Studies of Ambient Polycyclic Aromatic Hydrocarbons in the Los Angeles Atmosphere Application of a Chemical Species Balance Method with First Order Chemical Decay", Thesis, Master of Science in Engineering, UCLA. 

The Application of Factor Analysis to Urban Aerosol Source Resolution... 

Among these techniques are various forms of a statistical method called factor analysis. Several forms of factor analysis have been applied to the problem of aerosol source resolution. These different forms provide several different frameworks in which to examine aerosol composition data and Interpret it in terms of source contributions. 

A Varimax rotation (Vl ) is often used to achieve it. However, simple structure may not be the most useful criterion for environmental source resolution since an element may be present in an aerosol sample because of its emission by several sources. The variance should, therefore, be spread over several factors rather than concentrated in one. 

A dichotomous sampler with a fine to coarse cut point of about 2 pm is preferred because of the bimodal nature of the ambient aerosol and its sources. This type of physical separation according to particle size, is the first stage of source resolution since it separates the particles as well as sources into two broad classes. 

Sampling for less than 24 hours should substantially improve source resolution due to more precisely defined time dependence and enhanced signal to noise ratios. Sampling for less than 24 hours does Increase cost substantially, and it may not be necessary for the first phase of a study. 

Venkataraman, C., and S. K. Friedlander, Source Resolution of Fine Particulate Polycyclic Aromatic Hydrocarbons Using a Receptor Model Modified for Reactivity, J. Air Waste Manage. Assoc., 44, 1103-1108 (1994c). 

Protein and metal ion(s) Source Resolution of crystallographic data (nm) Metal binding sites1 Ref... 

Pratsinis, S. E., Zeldin, M. D., and Ellis, E. C. (1988) Source resolution of fine carbonaceous aerosol by principal component-stepwise regression analysis, Environ. Sci. Technol. 22, 212-216. 

Linearity and sensitivity using a continuum source will of course be improved as the bandpass of the monochromator (and hence the band of unabsorbed radiation) is narrowed however, this results in a loss of source intensity and an increased noise level as more gain is required on the detector. In order to approach the sensitivity of a line source, resolution beyond the capabilities of ordinary spectrophotometers would be required. 

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