Improved Time-Resolved Measurements of Inorganic Ions in Particulate Matter by PILS-IC Integrated with a Sample Pre-Concentration System

Figures & data

FIG. 1. Schematic diagram of the six-way valve and of the cartridge used for sample pre-concentration and injection.

TABLE 1 Analytical performances of the pre-concentration cartridges (break-through volume, capacity, and recovery percentage): limit of detection (LOD) and limit of quantification (LOQ) of the pc-PILS-IC and the PILS-IC (N = 6)

	Cartridge performances			pcPILS		PILS
	Breakthrough (mL)	Capacity (μg)	R ± SD (%)	LOD (μg m^–3)	LOQ (μg m^–3)	LOD (μg m^–3)	LOQ (μg m^–3)
Br^−	120	12	99 ± 4	—	—	—	—
Li^+	25	2.5	98 ± 2	—	—	—	—
Cl^−	30	3.0	101 ± 6	0.01	0.02	0.02	0.04
NO2^−	65	6.5	97 ± 4	0.001	0.002	0.01	0.03
NO3^−	65	6.5	100 ± 2	0.003	0.005	0.05	0.08
SO4^2−	>250	>25	96 ± 3	0.02	0.04	0.2	0.6
Na^+	50	5.0	98 ± 2	0.01	0.01	0.02	0.03
NH4^+	70	7.0	101 ± 3	0.007	0.01	0.1	0.2
K^+	85	8.5	96 ± 6	0.005	0.007	0.07	0.1
Mg^2+	>250	>25	99 ± 8	0.01	0.02	0.1	0.3
Ca^2+	>250	>25	97 ± 12	0.02	0.04	0.3	0.6

FIG. 2. Comparison of nitrate, sulfate, and ammonium concentration as measured by the pcPILS-IC and by the HR-TOF-AMS.

FIG. 3. Time pattern of natural radioactivity during the intensive measurement period.

FIG. 4. Time patterns of chloride, nitrite, sodium, magnesium, potassium, and calcium determined by the pcPILS-IC.

FIG. 5. Time pattern of SO₄²⁻, Na⁺, Cl⁻, and Mg²⁺ concentration during 2 and 3 February.