type of acid, , , , , , , , , , , whereas the more predominant inorganic anions (e.g., sulfate, sulfite, nitrate, and chloride) have typically somewhat higher concentrations.56
AEC is the preferred technique when dealing with large sample numbers , , - since rain samples can be injected directly, perhaps after filtration if particles are present. Organic acids are separated on anion exchange columns and then detected by suppressed conductivity. Detection limits thus achieved are in the low p.molar range, which is adequate for rain samples. Inorganic anion concentrations in rain are not high enough to interfere with organic acid peak separation and, hence, they are even sometimes quantified simultaneously with organic acids, thus further streamlining the analytical process.70,71 Similarly, methods utilizing CZE are capable of determining inorganic anions and organic acids simultaneously while achieving low detection limits.82,83 Interestingly, these CZE methods have been employed for measurements of single raindrops.
GC methods tend to be more time consuming due to necessary sample preparation steps
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