## 3 Results and Analysis
### Plasma Degradation Effect of Five Acaricides on the Surface of Kumquats  
The influence of discharge voltage and treatment time on the degradation of avermectin is shown in Figure 3A. The results of the variance analysis indicate that both the  
Figure 2: Liquid chromatography-mass spectrometry (LC-MS) chromatograms of acaricide residues on the surface of kumquats before and after plasma treatment. discharge voltage and treatment time have a significant effect on the degradation rate of avermectin (\(p<0.05\)), and the degradation rate of avermectin increases with increasing discharge voltage. As shown in the figure, when the discharge voltage is 10 kV and the treatment time is 20 min, the discharge phenomenon is relatively obvious, and the degradation rate is 47.83%. When the voltage is increased to 20 kV and the treatment time is 20 min, the discharge phenomenon is more intense, and the degradation rate is 80.67%. The main reason for the increase in avermectin degradation rate with increasing discharge voltage may be that, within a certain voltage range, as the discharge voltage increases, the electric field energy increases, and therefore, the quantity of reactive species, such as ozone, and high-energy electrons in low plasma increases within a unit of time. These active substances react with more pesticide molecules to decompose them, thus increasing their degradation rate. Figure 3: The influence of discharge voltage and treatment time on the degradation rate of avermectin (**A**), bifenazate (**B**), spiromesifen (**C**), etoxazole (**D**) and lufenuron (**E**). The degradation rate of avermectin increases with the increase in treatment time. When the discharge voltage is 20 kV, the degradation rate of avermectin is 49.24% after 10 min of treatment, and it increases to 80.67% after 20 min of treatment. The main reason for the increase in avermectin degradation rate with increasing treatment time is the presence of more active substances in the plasma, resulting in a higher degradation rate. The influence of discharge voltage and treatment time on the degradation of bifenazate is shown in Figure 3B. The results of the variance analysis indicate that both discharge voltage and treatment time have significant effects on the degradation rate of benzene sulfonyl hydrazide (\(p<0.05\)), and the degradation rate of bifenazate increases with increasing discharge voltage. As shown in the figure, when the discharge voltage is 10 kV and the treatment time is 20 min, the degradation rate of bifenazate is 16.18%, and obvious discharge phenomena are observed. When the discharge voltage is increased to 20 kV and the treatment time is also 20 min, the degradation rate increases significantly to 79.52%. The main reason for the increase in the degradation rate of bifenazate with increasing discharge voltage is the same as that of avermectin, which will not be further elaborated here. The degradation rate of benzene sulfonyl hydrazide increases with the increase in treatment time. When the discharge voltage is 20 kV and the treatment time is 10 min, the degradation rate of bifenazate is 49.24%, and when the treatment time is increased to 20 min, the degradation rate increases to 80.67%. However, unlike avermectin, the degradation rate of bifenazate is lower when the discharge voltage is lower. When the discharge voltage is 10 kV and the treatment time is 10 min, the degradation rate of bifenazate is only 13.41%, and when the treatment time is increased to 20 min, the degradation rate is only 16.18%. This indicates that the degradation effect of bifenazate is not significant when the discharge voltage is low, and the influence of discharge voltage is more significant compared to treatment time. The effects of voltage and treatment time on the degradation of spiromesifen are shown in Figure 3C. The results of variance analysis indicate that both discharge voltage and treatment time have significant effects on the degradation rate of spiromesifen (\(p<0.05\)).