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排序方式: 共有354条查询结果,搜索用时 15 毫秒
351.
巴西UC认证     
介绍了巴西的产品管制范围,认证程序和认证标识等,并对巴西 UC 认证的产品分类,强制性 UC 认证产品目录和非强制性 UC 认证产品目录等进行了说明,给出了申请巴西 UC 认证过程中的注意事项和建议。  相似文献   
352.
The photovoltaic (PV) power output might be frequently curtailed to maintain electricity supply-demand balance in future power systems. In our previous study, we proposed a new method for updating the battery energy storage system (BESS) charge/discharge and the generator unit commitment (UC) schedules based on the forecasted and actual PV power outputs. The forecast dataset was updated every 3 h (eight times a day). Although the simulation results showed that the proposed method could reduce the supply-demand imbalances, it was not clear whether the forecasted or actual values made contributions. Therefore, in this study, we propose and evaluate a real-time scheduling and operation method using the forecasted and actual PV power outputs assuming that the forecasted dataset is updated only once a day. Numerical simulations of supply-demand operations are conducted on the power system model of the Kanto area of Japan for one year. The results show that the previous study method has a slight advantage over proposed method in terms of curtailed PV energy and operational cost of thermal generators reduction, but the difference is very small, indicating that the contribution of the actual PV power outputs is greater than that of the forecasted PV power outputs.  相似文献   
353.
《Ceramics International》2023,49(3):4956-4963
High-quality hexagonal NaYF4:Er/Yb particles and monodisperse copper(I) sulfide nanoparticles (NPs) were obtained with the solvothermal method and the hot-injection method, respectively. The hybrid structure of semiconductor-insulator-semiconductor (SIS) was constructed for upconversion luminescence (UCL). The results showed that compared with that of NaYF4:Er/Yb-SiO2 particles, the luminous intensity of SIS was promoted by 12.5 folds, and the quantum yield of SIS can reach to 0.89%. Furthermore, the optical field distribution in the vicinity of hybrid structure of SIS was numerically simulated based on the finite-time domain-difference method (FDTD). The UCL enhancement of the SIS originates from the amplified optical field, which was attributed to the localized surface plasmon resonance (LSPR) effect of copper(I) sulfide NPs and the local effect of the copper(I) sulfide film on the excited light.  相似文献   
354.
《Ceramics International》2023,49(20):33316-33323
Y2O3: x% Er3+ (x=5, 7, 10, 12, 15) and Y2O3: 10% Er3+,x% K+ (x=0, 1, 3, 5, 7, 10, 15) phosphors were successfully prepared by a low-temperature combustion method. The structure as well as the absorption/emission spectra of phosphors were investigated. The effect of doping concentration of K+ ions on the upconversion (UC) luminescence of Y2O3: 10% Er3+ phosphor was examined and the possible optical transitions were discussed. The results showed that K+ ion doping not only changed the microstructure and crystallinity of the phosphors, but also enhanced its UC luminescence intensity. The Y2O3: 10% Er3+, 7% K+ phosphor exhibit the strongest UC emission intensity. Compared with the Y2O3: 10% Er3+ phosphor, the UC luminescence intensity at 563 nm and 661 nm was enhanced by 67.8 and 27.3 times for the K-codoped samples, respectively. The phosphor with the optimal doping concentration was mixed with a polymer to form a composite film, which was employed for the fabrication of near-infrared (NIR) photo-responsive detection devices. The device exhibited strong photo-current response to NIR light at 980 nm, implying that our work could inspire new design strategy for the development of NIR photo-detection devices.  相似文献   
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