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Objective: To establish a new QuEChERS-ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the detection of chlorantraniliprole and penoxsulam residues in rice. Methods: After the sample was extracted with 0.2% formic acid-acetonitrile, purified with N-propylethylenediamine (PSA) and graphitized carbon black (GCB) packing, 0.2% formic acid water and acetonitrile were used as mobile phases for gradient elution, and then subjected to C18 chromatography. UPLC-MS/MS was used to column separation and determination. Results: The limits of quantification (LOQ) of chlorantraniliprole and penoxsulam were both 0.004 mg/kg, and the method detection limits (LOD) were both 0.001 mg/kg. Chlorantraniliprole and penoxsulam had a good linear relationship in the range of 0.002~0.5 mg/L, and their coefficient was greater than 0.993. At the addition levels of 0.05, 0.1, and 0.5 mg/kg, the average recovery rates of chlorantraniliprole and penoxsulam were 86% to 110% with the relative standard deviations (RSD) of 1.5% to 6.1%. Conclusion: This method is efficient and simple, has good stability and high sensitivity, and is suitable for the detection of chlorantraniliprole and penoxsulam in rice.

The thermal behavior and kinetic study of lignocellulosic biomass (rice straw (RS)) and linear low-density polyethylene (LLDPE) pyrolysis over modified ZSM-5 catalyst were investigated using thermo-gravimetric analysis (TGA). Cellulose and lignin were used as model compounds of biomass in order to investigate the reaction mechanism of lignocellulosic biomass and polyethylene co-pyrolysis. Results showed that RS&LLDPE co-pyrolysis was more complicated than that of the individual components. The activation energy (E) of RS, and RS&LLDPE pyrolysis were 79.61 kJ/mol and 59.70 kJ/mol respectively, suggesting that there was a positive synergistic interaction between RS and LLDPE. The addition of LLDPE with lignin co-pyrolysis obtained a lower apparent activation energy (33.39 kJ/mol) compared to raw lignin pyrolysis (53.10 kJ/mol). Results indicated that the Cobalt modified ZSM-5 catalyst was able to improve the reaction rate of RS and LLDPE co-pyrolysis; also the addition of Co/ZSM-5 catalyst resulted in a lower apparent activation energy during cellulose and LLDPE co-pyrolysis. [ABSTRACT FROM AUTHOR]