Table 3.

Pollutant Ratios

	Cluster 1	Cluster 2	Cluster 3	Cluster 4	Cluster 5
Fe/Si	0.80	0.87	1.25	0.71	1.00
K/Si	0.52	0.40	0.74	0.57	0.67
NO/NO2	0.81	0.98	1.70	0.54	1.01
S/PM2.5	0.10	0.09	0.09	0.13	0.10
BC/PM2.5	0.07	0.09	0.08	0.05	0.07
Ca/Si	0.42	0.39	0.49	0.36	0.50
Ni/V	0.75	0.76	1.01	0.62	0.97
PN/PM2.5	2534	1861	2486	654	3851