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A rapid, specific and sensitive multiresidue method based on the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) sample preparation method and gas chromatography with mass spectrometric detection by selected ion monitoring (GC/MS-SIM) has been developed for the routine analysis of 109 pesticides in rice. The method uses one quantification ion and two identification ions. Temperature control during sample preparation helps improve the recovery of thermally labile pesticides such as captan. The method was validated by the analysis of samples spiked at 0.025-0.150 mg/kg in rice matrix. The recoveries of all pesticides were between 80% and 115% with a relative standard deviation of less than 15%. The limit of quantitation (LOQ) for most compounds met the maximum residue limits (MRLs) for pesticides in rice in Korea.

Laser-induced copper plasma emission was investigated by time-integrated spatially resolved spectrometry. The comparative work on the plasma emission characteristics—specifically, self-absorption, line broadening, emission intensity, and metal ion formation—was carried out by the use of two different laser systems (XeCl excimer: = 308 nm; Nd:YAG: = 1064 and 532 nm). The characteristics of plasma emission produced by different wavelength radiation on copper atomic and ion lines under various atmospheric gases (argon, neon, and helium) and pressures (760–10 Torr) are presented. The differences in self-absorption and line broadening phenomena in the plasma location were explained by shock wave-driven excitation mechanism for atoms in the outer region in the plasma. The excitation temperatures of the plasma induced by 308- or 532-nm irradiation were also much higher that those induced by 1064-nm irradiation.