Quality assurance and quality control
The recoveries of the PCDD/F, PCB, and PCN internal standards in the ambient air samples were in the ranges of 42e118%, 42e119%, and 45e115%, respectively (Table S1). The following quality control criteria were used when identifying a target compound: (a) the chromatographic retention time matched that of the corre- sponding standard compound; (b) the signal-to-noise ratio was greater than 3:1; and (c) the isotopic ratio between the quantitation and confirmation ions was within ±15% of the theoretical value. One method blank was included in each batch of samples, and the blanks were spiked with the same amounts of internal standard as were the samples. No target compounds were detected in any of the blank samples.
Quality assurance and quality controlThe recoveries of the PCDD/F, PCB, and PCN internal standards in the ambient air samples were in the ranges of 42e118%, 42e119%, and 45e115%, respectively (Table S1). The following quality control criteria were used when identifying a target compound: (a) the chromatographic retention time matched that of the corre- sponding standard compound; (b) the signal-to-noise ratio was greater than 3:1; and (c) the isotopic ratio between the quantitation and confirmation ions was within ±15% of the theoretical value. One method blank was included in each batch of samples, and the blanks were spiked with the same amounts of internal standard as were the samples. No target compounds were detected in any of the blank samples.
การแปล กรุณารอสักครู่..
