Tomato （Lycopslcon esculentum Mill.） plants grown in a greenhouse were irradiated with two different levels of UV-B, namely 8.82 （T1） and 12.6 kJ/m^2 per day （T2）. Ethylene production, 1-aminocyclopropane-1-carb...Tomato （Lycopslcon esculentum Mill.） plants grown in a greenhouse were irradiated with two different levels of UV-B, namely 8.82 （T1） and 12.6 kJ/m^2 per day （T2）. Ethylene production, 1-aminocyclopropane-1-carboxylate （ACC） content, 1-（malonylamino） cyclopvopane-1-carboxylic acid （MACC） content, gene expression of ACC aynthase （EC 4.4.1.14）, and ACC oxidase activity in tomato leaves were determined. The results Indicated that ACC content, the activity of ACC synthase and ACC oxidase, and ethylene production Increased continuously under low doses of UV-B radiation, whereas at high doses of radiation these parameters Increased during the first 12 d and then started to decrease. The MACC content increased continuously over 18 d under both doses of UV-B irradiation. The changes in ACC content, ACC synthaae activity, ACC oxidase activity, the transcriptional level of the ACC synthase gene, and ethylene production were consistent with each other, suggesting that ACC synthase was the key enzyme in ethylene biosynthesis and that ethylene production in tomato leaf tissues under UV-B radiation could be regulated by the expression of the ACC synthase gene. The results also indicate that the change in ethylene metabolism may be an adaptive mechanism to enhanced UV-B radiation.展开更多
The ethylene project jointly invested by the Beijing Municipal Government and China National Petroleum and Natural Gas Corporation is one of the state’s key projects planned for the Eight Five-Year Plan period, invol...The ethylene project jointly invested by the Beijing Municipal Government and China National Petroleum and Natural Gas Corporation is one of the state’s key projects planned for the Eight Five-Year Plan period, involving a total investment of RMB 4. 1 billion in capital construction and technical renovation. Known as the No. one project, it is the largest project ever undertaken in Beijing. The project began to be constructed in June 1992 and and is planned to be put into production by展开更多
Tomato is one of the extensively consumed vegetable crops worldwide. The regular consumption of tomato decreases the incidence of chronic degenerative diseases such as certain types of cancer and cardiovascular diseas...Tomato is one of the extensively consumed vegetable crops worldwide. The regular consumption of tomato decreases the incidence of chronic degenerative diseases such as certain types of cancer and cardiovascular diseases. The objective of this study was to find an appropriate method that not only reduces tomatoes decay, but also maintains its post-harvest quality. A factorial experiment based on randomized complete block design with three replications was conducted to evaluate effects of ultraviolet（UV）-C and CaCl_2 applications on tomato during storage. The traits studied included ethylene, polygalacturonase（PG） activity, pectin methyl esterase（PME） activity, firmness, total phenol content, and fungal-induced decay were measured weekly during 35 days of storage. Both UV-C and CaCl_2 treatments had positive effects on tomato quality as compared to control treatment. The 3 and 4.5 k J m^（-2） levels of UV-C and 2% CaCl_2 had positive effects on quality characteristics, respectivly. Fruits treated by UV-C and CaCl_2 had higher phenol and firmness, and less PME activity, PG activity, ethylene production, and decay than the control fruits. In conclusion, increasing in storage duration significantly affected the fruits quality by increasing in ethylene, PME activity, PG activity, decay and decreasing the phenol content and firmness. But UV-C and CaCl_2 led to significant decrease in this adverse impact relative to control treatment.展开更多
The study reports progress in developing a molybdenum carbide-based catalyst for co-processing ethane and CO_(2).The cobalt promoting of molybdenum carbide improved the activity and stability of ethane transformation ...The study reports progress in developing a molybdenum carbide-based catalyst for co-processing ethane and CO_(2).The cobalt promoting of molybdenum carbide improved the activity and stability of ethane transformation in the presence of CO_(2) substantially without any impact on ethylene selectivity.The Mo-Co supported catalyst also showed interesting performance in catalyzing ethane dry reforming and that application could be a perspective further use for this system.In addition,the comprehensive analysis of mono-and bi-metallic catalysts revealed that Co-promoting prevented rapid Mo-carbide oxidation.Further,tuning operation conditions allowed to control catalyst’s selectivity and maximize CO_(2) utilization or ethylene formation.展开更多
基金Supported by the National Natural Science Foundation of China （30170038, 90302010）, ＂Hundred talents＂ project of the Chinese Academy of Sciences, Gansu Key Technologies R＆D Program （GS022-A41-045）, and Gansu Agricultural Bio-technology Research ＆ Development Project. Acknowledgements The authors thank Dr Akira Nakatsuka （Laboratory of Postharvest Agriculture, Faculty of Agriculture, 0kayama University, 0kayama, Japan） for providing the ACC synthase clone.
文摘Tomato （Lycopslcon esculentum Mill.） plants grown in a greenhouse were irradiated with two different levels of UV-B, namely 8.82 （T1） and 12.6 kJ/m^2 per day （T2）. Ethylene production, 1-aminocyclopropane-1-carboxylate （ACC） content, 1-（malonylamino） cyclopvopane-1-carboxylic acid （MACC） content, gene expression of ACC aynthase （EC 4.4.1.14）, and ACC oxidase activity in tomato leaves were determined. The results Indicated that ACC content, the activity of ACC synthase and ACC oxidase, and ethylene production Increased continuously under low doses of UV-B radiation, whereas at high doses of radiation these parameters Increased during the first 12 d and then started to decrease. The MACC content increased continuously over 18 d under both doses of UV-B irradiation. The changes in ACC content, ACC synthaae activity, ACC oxidase activity, the transcriptional level of the ACC synthase gene, and ethylene production were consistent with each other, suggesting that ACC synthase was the key enzyme in ethylene biosynthesis and that ethylene production in tomato leaf tissues under UV-B radiation could be regulated by the expression of the ACC synthase gene. The results also indicate that the change in ethylene metabolism may be an adaptive mechanism to enhanced UV-B radiation.
文摘The ethylene project jointly invested by the Beijing Municipal Government and China National Petroleum and Natural Gas Corporation is one of the state’s key projects planned for the Eight Five-Year Plan period, involving a total investment of RMB 4. 1 billion in capital construction and technical renovation. Known as the No. one project, it is the largest project ever undertaken in Beijing. The project began to be constructed in June 1992 and and is planned to be put into production by
文摘Tomato is one of the extensively consumed vegetable crops worldwide. The regular consumption of tomato decreases the incidence of chronic degenerative diseases such as certain types of cancer and cardiovascular diseases. The objective of this study was to find an appropriate method that not only reduces tomatoes decay, but also maintains its post-harvest quality. A factorial experiment based on randomized complete block design with three replications was conducted to evaluate effects of ultraviolet（UV）-C and CaCl_2 applications on tomato during storage. The traits studied included ethylene, polygalacturonase（PG） activity, pectin methyl esterase（PME） activity, firmness, total phenol content, and fungal-induced decay were measured weekly during 35 days of storage. Both UV-C and CaCl_2 treatments had positive effects on tomato quality as compared to control treatment. The 3 and 4.5 k J m^（-2） levels of UV-C and 2% CaCl_2 had positive effects on quality characteristics, respectivly. Fruits treated by UV-C and CaCl_2 had higher phenol and firmness, and less PME activity, PG activity, ethylene production, and decay than the control fruits. In conclusion, increasing in storage duration significantly affected the fruits quality by increasing in ethylene, PME activity, PG activity, decay and decreasing the phenol content and firmness. But UV-C and CaCl_2 led to significant decrease in this adverse impact relative to control treatment.
文摘The study reports progress in developing a molybdenum carbide-based catalyst for co-processing ethane and CO_(2).The cobalt promoting of molybdenum carbide improved the activity and stability of ethane transformation in the presence of CO_(2) substantially without any impact on ethylene selectivity.The Mo-Co supported catalyst also showed interesting performance in catalyzing ethane dry reforming and that application could be a perspective further use for this system.In addition,the comprehensive analysis of mono-and bi-metallic catalysts revealed that Co-promoting prevented rapid Mo-carbide oxidation.Further,tuning operation conditions allowed to control catalyst’s selectivity and maximize CO_(2) utilization or ethylene formation.
