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排序方式: 共有473条查询结果,搜索用时 765 毫秒
471.
Matteo L. Zaffalon Ye Wu Francesca Cova Luca Gironi Xiaoming Li Valerio Pinchetti Yang Liu Muhammad Imran Alessia Cemmi Ilaria Di Sarcina Liberato Manna Haibo Zeng Sergio Brovelli 《Advanced functional materials》2023,33(48):2305564
The search for efficient, re-absorption-free scintillators has recently focused the attention on antimony-based halides, which exhibit largely Stokes shifted luminescence due to radiative recombination of excitons self-trapped (STE) in strongly Jahn–Teller distorted Sb3+ color centers. Here, the synthesis of a hybrid structure is reported with chemical formula (C13H14N3)3SbCl6 consisting of spatially isolated [SbCl6]3− octahedra separated by organic N,N'-diphenylguanidinium (Gua) molecules. The optical properties of this material are mainly determined by the inorganic component and are characterized by a pronounced Stokes shift of ≈1.3 eV and a room-temperature photoluminescence (PL) efficiency of up to 85%. Remarkably, highly efficient radioluminescence (RL) is observed with scintillation light yields of ≈2000 ph MeV−1 using both soft X-rays and a 124 keV gamma source. Temperature-dependent PL and RL measurements confirm the minor role of non-radiative channels, which are completely suppressed below 100 K. Thermally stimulated luminescence measurements suggest that the traps in Gua3SbCl6 crystals have a significantly large energy depth distribution below the absorbing state. 相似文献
472.
Quantification of the performance degradation on the annual energy production (AEP) of a wind farm due to leading-edge (LE) erosion of wind turbine blades is important to design cost-effective maintenance plans and timely blade retrofit. In this work, the effects of LE erosion on horizontal axis wind turbines are quantified using infrared (IR) thermographic imaging of turbine blades, as well as meteorological and SCADA data. The average AEP loss of turbines with LE erosion is estimated from SCADA and meteorological data to be between 3% and 8% of the expected power capture. The impact of LE erosion on the average power capture of the turbines is found to be higher at lower hub-height wind speeds (peak around 50% of the turbine rated wind speed) and at lower turbulence intensity of the incoming wind associated with stable atmospheric conditions. The effect of LE erosion is investigated with IR thermography to identify the laminar to turbulent transition (LTT) position over the airfoils of the turbine blades. Reduction in the laminar flow region of about 85% and 87% on average in the suction and pressure sides, respectively, is observed for the airfoils of the investigated turbines with LE erosion. Using the observed LTT locations over the airfoils and the geometry of the blade, an average AEP loss of about 3.7% is calculated with blade element momentum simulations, which is found to be comparable with the magnitude of AEP loss estimated through the SCADA data. 相似文献
473.
Laura M. de Kort Oscar E. Brandt Corstius Valerio Gulino Andrei Gurinov Marc Baldus Peter Ngene 《Advanced functional materials》2023,33(13):2209122
Sodium-based complex hydrides have recently gained interest as electrolytes for all-solid-state batteries due to their light weight and high electrochemical stability. Although their room temperature conductivities are not sufficiently high for battery application, nanocomposite formation with metal oxides has emerged as a promising approach to enhance the ionic conductivity of complex hydrides. This enhancement is generally attributed to the formation of a space charge layer at the hydride-oxide interface. However, in this study it is found that the conductivity enhancement results from interface reactions between the metal hydride and the oxide. Highly conductive NaBH4 and NaNH2/oxide nanocomposites are obtained by optimizing the interface reaction, which strongly depends on the interplay between the surface chemistry of the oxides and the reactivity of the metal hydrides. Notably, for NaBH4, the best performance is obtained with Al2O3, while NaNH2/SiO2 is the most conductive NaNH2/oxide nanocomposite with conductivities of, respectively, 4.7 × 10−5 and 2.1 × 10−5 S cm−1 at 80 °C. Detailed structural characterization reveals that this disparity originates from the formation of different tertiary interfacial compounds, and is not only a space charge effect. These results provide useful insights for the preparation of highly conductive nanocomposite electrolytes by optimizing interface interactions. 相似文献