Long-duration manned submersible missions require advanced life support systems (LSS) that can regenerate air, water and food. This study presented two CO_2-capture methods used in LSS, CO_2 removal with diethanolamin...Long-duration manned submersible missions require advanced life support systems (LSS) that can regenerate air, water and food. This study presented two CO_2-capture methods used in LSS, CO_2 removal with diethanolamine (DEA) and cryo-freezing with liquid oxygen. Both processes were modeled and simulated with HYSYS simulator. The performance of the two types of module was compared, and the results showed that the latter could be advantageous over the former in specific power, facility scale, operation reliability and safety. Economic evaluation suggested the latter cost only half of the former. Cryo-capture module could be an alternative for underwater LSS because of its efficiency and compactness.展开更多
Chlordecone, one of the most persistent organochlorine pesticides, was applied between 1972 and 1993 in banana fields in the French West Indies, which results in long-term pollution of soils and contamination of water...Chlordecone, one of the most persistent organochlorine pesticides, was applied between 1972 and 1993 in banana fields in the French West Indies, which results in long-term pollution of soils and contamination of waters, aquatic biota, and crops. As human exposure to chlordecone is mainly due to food contamination, early research was focused on chlordecone transfer to crops. Field trials were conducted to investigate chlordecone contamination of yam, sweet potato, turnip, and radish grown on a Ferralic Nitisol polluted by chlordecone. We also carried out trials on yam, courgette, and tomato under greenhouse conditions with homogenized Andosol and Nitisol, polluted by chlordecone to various extents. Our results indicated that i) all tubers were contaminated in accordance with the chlordecone content of the soils; ii) the plant contamination capacity of the Nitisol was greater than that of the Andosol; and iii) whatever the soil type, tuber contamination was related to the soil volumetric content of dissolved chlordecone. Nevertheless, no tubers showed sufficient chlordecone uptake for efficient soil decontamination by means of plant extraction. Soil contact accounted for most of the root crop contamination, which was inversely proportional to the tuber size. Internal transfer might also increase root crop contamination when the root central cylinder contained raw sap flow, as in the case of turnip or radish. Courgette fruits showed high contamination without soil contact. Thus, further research is needed to explore the pattern of both below- and aboveground plant chlordecone contamination and assess the hypothesis of its correlation with sap flow. Finally, we used our results to build a decisionmaking tool for farmers, relating soil pollution with the maximal contamination of the harvested organs to predict crop contamination and thus assisting farmers in making crop choices at planting in order to conform with the European Union's regulations.展开更多
We propose a novel pressure sensor based on the combination of the ring resonator with two straight waveguides and a two-end fixed beam.The principle of this device is acquiring the system static pressure by monitorin...We propose a novel pressure sensor based on the combination of the ring resonator with two straight waveguides and a two-end fixed beam.The principle of this device is acquiring the system static pressure by monitoring the changes in the transmission wavelength shift of the ring resonator with double waveguides.The numerical results show that the sensitivity of the system is up to 49.3 pm/kPa while the pressure range is 0—300 kPa.The thickness of the fixed beam is an important factor which impacts the sensitivity of the system.This device can provide support for fabricating high sensitivity and low cost micro pressure sensors.展开更多
文摘Long-duration manned submersible missions require advanced life support systems (LSS) that can regenerate air, water and food. This study presented two CO_2-capture methods used in LSS, CO_2 removal with diethanolamine (DEA) and cryo-freezing with liquid oxygen. Both processes were modeled and simulated with HYSYS simulator. The performance of the two types of module was compared, and the results showed that the latter could be advantageous over the former in specific power, facility scale, operation reliability and safety. Economic evaluation suggested the latter cost only half of the former. Cryo-capture module could be an alternative for underwater LSS because of its efficiency and compactness.
基金Supported by the Ministry of Ecology and Sustainable Development and the Ministry of Agriculture and Food,France,the French National Agency of Research,and the French National Chlordecone Action Plan
文摘Chlordecone, one of the most persistent organochlorine pesticides, was applied between 1972 and 1993 in banana fields in the French West Indies, which results in long-term pollution of soils and contamination of waters, aquatic biota, and crops. As human exposure to chlordecone is mainly due to food contamination, early research was focused on chlordecone transfer to crops. Field trials were conducted to investigate chlordecone contamination of yam, sweet potato, turnip, and radish grown on a Ferralic Nitisol polluted by chlordecone. We also carried out trials on yam, courgette, and tomato under greenhouse conditions with homogenized Andosol and Nitisol, polluted by chlordecone to various extents. Our results indicated that i) all tubers were contaminated in accordance with the chlordecone content of the soils; ii) the plant contamination capacity of the Nitisol was greater than that of the Andosol; and iii) whatever the soil type, tuber contamination was related to the soil volumetric content of dissolved chlordecone. Nevertheless, no tubers showed sufficient chlordecone uptake for efficient soil decontamination by means of plant extraction. Soil contact accounted for most of the root crop contamination, which was inversely proportional to the tuber size. Internal transfer might also increase root crop contamination when the root central cylinder contained raw sap flow, as in the case of turnip or radish. Courgette fruits showed high contamination without soil contact. Thus, further research is needed to explore the pattern of both below- and aboveground plant chlordecone contamination and assess the hypothesis of its correlation with sap flow. Finally, we used our results to build a decisionmaking tool for farmers, relating soil pollution with the maximal contamination of the harvested organs to predict crop contamination and thus assisting farmers in making crop choices at planting in order to conform with the European Union's regulations.
基金supported by the National Natural Science Foundation of China(No.6172044)the Natural Science Foundation of Hebei Province(No.F2012203204)
文摘We propose a novel pressure sensor based on the combination of the ring resonator with two straight waveguides and a two-end fixed beam.The principle of this device is acquiring the system static pressure by monitoring the changes in the transmission wavelength shift of the ring resonator with double waveguides.The numerical results show that the sensitivity of the system is up to 49.3 pm/kPa while the pressure range is 0—300 kPa.The thickness of the fixed beam is an important factor which impacts the sensitivity of the system.This device can provide support for fabricating high sensitivity and low cost micro pressure sensors.
