| Summary: | 碩士 === 國立中興大學 === 化學系 === 84 === This study has
been investigated for the practicability of residues analysis of
organophosphorus pesticides in soil using microwave-assisted
extraction. The effect of microwave-assisted extraction was
emphasized in the study. Finally, GC/P-FPD method for
qualitative and quantitative determination was adopted.
First of all the possible factors for the decomposition of
organophosphorus pesticides with microwave were considered
without the existence of matrix. The factors were the kind of
solvent, power of microwave and the heating time etc. The
results were shown that the effects were not obvious for solvent
types. When the power of microwave was too high and the heating
time too long, the recovery of organophosphorus pesticides were
lowered. The investigations of real sample were proceeded in
similar way. The best condition from the results were 20mL n-
hexane/ethyl acetate (v/v,1+1) for extraction solvent, the power
of microwave 75% and the heating time 5 minutes. Real samples
were extracted by microwave-assisted extraction, then the
extract was filtered and concentrated and then injected in GC.
The effect for the existence of water was considered, the
recovery of 5 organophosphorus pesticides were lowered. The
setting effect for organophosphorus pesticides was observed. In
10 days, organophosphorus pesticides had already been
decomposed. sphorus
pesticides could be determined with GC/P-FPD in 16 minutes. The
linear relative coefficients for calibration curve of real
sample were higher than 0.99. Besides of the recovery of
dichlorvos (31.9~68.0%), the recovery of other 4
organophosphorus pesticides were 87.5~127%, and limits of
detection were 35.32~109.1ppb.
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