The effects of treatment of chlorine dioxide （C1Oz） gas on postharvest physiology and preservation quality of green bell peppers were studied. Green bell peppers were collected in bags and treated with 0, 5, 10, 20,...The effects of treatment of chlorine dioxide （C1Oz） gas on postharvest physiology and preservation quality of green bell peppers were studied. Green bell peppers were collected in bags and treated with 0, 5, 10, 20, and 50 mg L^-1 ClO2 gas at 10±0.5℃ for over 40 d, and the changes in postharvest physiology and preservation quality of the peppers were evaluated during the storage. The inhibition of rot of the peppers was observed for all the tested ClO2 gas treatments. The rot rates of the treated samples were 50% lesser than those of the control after day 40 of storage. The highest inhibitory effect was obtained after 50 mg L^-1 ClO2 gas treatment, where the peppers did not decay until day 30 and showed only one-fourth of the rot rate of the control at day 40 of storage. The respiratory activity of the peppers was significantly （P〈0.05） inhibited by 20 and 50 mg L^-1 ClO2 treatments, whereas no significant effects on respiratory activity were observed with 5 and 10 mg L^-1 ClO2 treatments （P〉0.05）. Except for 50 mg L^-1 ClO2, malondialdenyde （MDA） contents in the peppers treated with 5, 10, or 20 mg L^-1 ClO2 were not significantly （P〉0.05） different from those in the control. Degradation of chlorophyll in the peppers was delayed by 5 mg L-1ClO2, but promoted by 10, 20, or 50 mg L^-1 ClO2. The vitamin C content, titratable acidity, and total soluble solids of the peppers treated by all the tested ClO2 gas did not significantly change during the storage. The results suggested that ClO2 gas treatment effectively delayed the postharvest physiological transformation of green peppers, inhibited decay and respiration, maintained some nutritional and sensory quality, and retarded MDA accumulation.展开更多
The explosion characteristics of chlorine dioxide gas have been studied for the first time in a cylindrical exploder with a shell capacity of 201. The experimental results have indicated that the lower concentration l...The explosion characteristics of chlorine dioxide gas have been studied for the first time in a cylindrical exploder with a shell capacity of 201. The experimental results have indicated that the lower concentration limit for the explosive decomposition of chlorine dioxide gas is 9.5% （[ClO2]/[air]）, whereas there is no corresponding upper concentration limit. The maximum pressure of explosion relative to the initial pressure was measured as 0.024 MPa at 10% ClO2 and 0.641 MPa at 90% ClO2. The induction time （the time from the moment of sparking to explosion） at 10% ClO2 was 2195 ms, but at 90% ClO2 the induction time was just 8 ms. The explosion reaction mechanism of ClO2 is of a degenerate chain-branching type involving the formation of a stable intermediate （Cl2O3）, from which the chain branching occurs.展开更多
文摘The effects of treatment of chlorine dioxide （C1Oz） gas on postharvest physiology and preservation quality of green bell peppers were studied. Green bell peppers were collected in bags and treated with 0, 5, 10, 20, and 50 mg L^-1 ClO2 gas at 10±0.5℃ for over 40 d, and the changes in postharvest physiology and preservation quality of the peppers were evaluated during the storage. The inhibition of rot of the peppers was observed for all the tested ClO2 gas treatments. The rot rates of the treated samples were 50% lesser than those of the control after day 40 of storage. The highest inhibitory effect was obtained after 50 mg L^-1 ClO2 gas treatment, where the peppers did not decay until day 30 and showed only one-fourth of the rot rate of the control at day 40 of storage. The respiratory activity of the peppers was significantly （P〈0.05） inhibited by 20 and 50 mg L^-1 ClO2 treatments, whereas no significant effects on respiratory activity were observed with 5 and 10 mg L^-1 ClO2 treatments （P〉0.05）. Except for 50 mg L^-1 ClO2, malondialdenyde （MDA） contents in the peppers treated with 5, 10, or 20 mg L^-1 ClO2 were not significantly （P〉0.05） different from those in the control. Degradation of chlorophyll in the peppers was delayed by 5 mg L-1ClO2, but promoted by 10, 20, or 50 mg L^-1 ClO2. The vitamin C content, titratable acidity, and total soluble solids of the peppers treated by all the tested ClO2 gas did not significantly change during the storage. The results suggested that ClO2 gas treatment effectively delayed the postharvest physiological transformation of green peppers, inhibited decay and respiration, maintained some nutritional and sensory quality, and retarded MDA accumulation.
基金supported by the National Natural Science Foundation of China (No.50774068) and Shanxi Provincial Science and Technology Department,China.
文摘The explosion characteristics of chlorine dioxide gas have been studied for the first time in a cylindrical exploder with a shell capacity of 201. The experimental results have indicated that the lower concentration limit for the explosive decomposition of chlorine dioxide gas is 9.5% （[ClO2]/[air]）, whereas there is no corresponding upper concentration limit. The maximum pressure of explosion relative to the initial pressure was measured as 0.024 MPa at 10% ClO2 and 0.641 MPa at 90% ClO2. The induction time （the time from the moment of sparking to explosion） at 10% ClO2 was 2195 ms, but at 90% ClO2 the induction time was just 8 ms. The explosion reaction mechanism of ClO2 is of a degenerate chain-branching type involving the formation of a stable intermediate （Cl2O3）, from which the chain branching occurs.
