Post-mortem methods cannot fulfill the requirement of monitoring the lifetime of the plasma facing components （PFC） and measuring the tritium inventory for the safety evaluation. Laserinduced breakdown spectroscopy ...Post-mortem methods cannot fulfill the requirement of monitoring the lifetime of the plasma facing components （PFC） and measuring the tritium inventory for the safety evaluation. Laserinduced breakdown spectroscopy （LIBS） is proposed as a promising method for the in situ study of fuel retention and impurity deposition in a tokamak. In this study, an in situ LIBS system was successfully established on EAST to investigate fuel retention and impurity deposition on the first wall without the need of removal tiles between plasma discharges. Spectral lines of D, H and impurities （Mo, Li, Si ） in laser-induced plasma were observed and identified within the wavelength range of 500-700 nm. Qualitative measurements such as thickness of the deposition layers, element depth profile and fuel retention on the wall are obtained by means of in situ LIBS. The results demonstrated the potential applications of LIBS for in situ characterization of fuel retention and co-deposition on the first wall of EAST.展开更多
Dust and impurity accumulation has a significant effect on the efficiency and performance of PV panel output power. It influences the transmittance of solar radiation from the PV panels surface. Scheduling weekly or m...Dust and impurity accumulation has a significant effect on the efficiency and performance of PV panel output power. It influences the transmittance of solar radiation from the PV panels surface. Scheduling weekly or monthly cleaning periods requires complete knowledge of area’s weather and environmental condition. In this study, an experimental-based investigation is conducted aiming for a proper scheduling cleaning periods by comparing the output power efficiency of two identical PV panels, the first being cleaned daily and the other cleaned monthly. Both are exposed to unstable weather condition with Sarayat season in April and May, winter and summer Shamal of Kuwait for one year. The results indicated a significant degradation of PV panel output power in April, May, October and December. A need for frequent weekly water washing is a necessity to maintain the power efficiency loss of 15.07%, 13.74%, 10.685% and 8.742% respectively, and frequent monthly water washing for the remaining months of the year.展开更多
基金Supported by the National Magnetic Confinement Fusion Science Program of China(Nos.2013GB105002,2015GB109001,and 2013GB109005)National Natural Science Foundation of China(Nos.11575243,11605238,11605023)+1 种基金Chinesisch-Deutsches Forschungs Project(GZ765)Korea Research Council of Fundamental Science and Technology(KRCF)under the international collaboration&research in Asian countries(PG1314)
文摘Post-mortem methods cannot fulfill the requirement of monitoring the lifetime of the plasma facing components （PFC） and measuring the tritium inventory for the safety evaluation. Laserinduced breakdown spectroscopy （LIBS） is proposed as a promising method for the in situ study of fuel retention and impurity deposition in a tokamak. In this study, an in situ LIBS system was successfully established on EAST to investigate fuel retention and impurity deposition on the first wall without the need of removal tiles between plasma discharges. Spectral lines of D, H and impurities （Mo, Li, Si ） in laser-induced plasma were observed and identified within the wavelength range of 500-700 nm. Qualitative measurements such as thickness of the deposition layers, element depth profile and fuel retention on the wall are obtained by means of in situ LIBS. The results demonstrated the potential applications of LIBS for in situ characterization of fuel retention and co-deposition on the first wall of EAST.
文摘Dust and impurity accumulation has a significant effect on the efficiency and performance of PV panel output power. It influences the transmittance of solar radiation from the PV panels surface. Scheduling weekly or monthly cleaning periods requires complete knowledge of area’s weather and environmental condition. In this study, an experimental-based investigation is conducted aiming for a proper scheduling cleaning periods by comparing the output power efficiency of two identical PV panels, the first being cleaned daily and the other cleaned monthly. Both are exposed to unstable weather condition with Sarayat season in April and May, winter and summer Shamal of Kuwait for one year. The results indicated a significant degradation of PV panel output power in April, May, October and December. A need for frequent weekly water washing is a necessity to maintain the power efficiency loss of 15.07%, 13.74%, 10.685% and 8.742% respectively, and frequent monthly water washing for the remaining months of the year.
