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61.
《Journal of the European Ceramic Society》2022,42(11):4528-4538
Ideal relaxor antiferroelectrics (RAFEs) have high field-induced polarization, low remnant polarization and very slim hysteresis, which can generate high recoverable energy storage Wrec and high energy storage efficiency η, thus attracting much attention for energy storage applications. True RAFEs, on the other hand, are extremely rare, and the majority of them contain environmentally hazardous lead. In this work, we use a viscous polymer rolling process to synthesize a novel and eco-friendly 0.65Bi0.5Na0.4K0.1TiO3-0.35[2/3SrTiO3-1/3Bi(Mg2/3Nb1/3)O3] (BNKT-ST-BMN) dielectric material, which possesses a very typical RAFE-like characteristic. As a result, this material has a high Wrec of 4.43 J/cm3 and a η of 86% at an electric felid of 290 kV/cm, as well as a high thermal stability of Wrec (>3 J/cm3) over a wide range of 30–140 °C at 250 kV/cm. Our findings suggest that the BNKT-ST-BMN material could be a potential candidate for use in energy storage pulse capacitors. 相似文献
62.
Chaofeng Zhu Jia Wang Meimei Zhang Xiaorong Ren Jianxing Shen Yuanzheng Yue 《Journal of the American Ceramic Society》2014,97(3):854-861
Luminescence glass is a potential candidate for the light‐emitting diodes (LEDs) applications. Here, we study the structural and optical properties of the Eu‐, Tb‐, and Dy‐doped oxyfluoride silicate glasses for LEDs by means of X‐ray diffraction, photoluminescence spectra, Commission Internationale de L'Eclairage (CIE) chromaticity coordinates, and correlated color temperatures (CCTs). The results show that the white light emission can be achieved in Eu/Tb/Dy codoped oxyfluoride silicate glasses under excitation by near‐ultraviolet light due to the simultaneous generation of blue, green, yellow, and red‐light wavelengths from Tb, Dy, and Eu ions. The optical performances can be tuned by varying the glass composition and excitation wavelength. Furthermore, we observed a remarkable emission spectral change for the Tb3+ single‐doped oxyfluoride silicate glasses. The 5D3 emission of Tb3+ can be suppressed by introducing B2O3 into the glass. The conversion of Eu3+ to Eu2+ takes place in Eu single‐doped oxyfluoride aluminosilicate glasses. The creation of CaF2 crystals enhances the conversion efficiency. In addition, energy transfers from Dy3+ to Tb3+ and Tb3+ to Eu3+ ions occurred in Eu/Tb/Dy codoped glasses, which can be confirmed by analyzing fluorescence spectra and energy level diagrams. 相似文献
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Yue Wu Yu Liu Ruidi Dou Wenjie Tang Bin Sun Tingting Gao Zhizhou Yang Guowei Zhou 《应用聚合物科学杂志》2020,137(16):48572
Synthesis of covalently linked porous polymers with high surface area and larger pore volume for two or more task-specific functionalities is always a big challenge. In this article, the facile Friedel–Crafts reaction is employed to construct the hierarchical hybrid porous polymers (HPPs) from tetraphenyladamantane and octavinylsilsesquioxane. The resulting polymers, HPP-1 to HPP-3, possessed the surface areas from 1356 to 1511 m2 g−1, and the pore volumes from 2.05 to 2.67 cm3 g−1. All these polymers feature micropores, mesopores, and macropores in nature. The resultant polymers exhibit high CO2 adsorption capacity up to 2.0 mmol g−1 (8.82 wt %), at 273 K, 1.0 bar, and the maximum Rhodamine B (RB) sorption capacity of 653.6 mg g−1. To illustrate the adsorption process, the effects of factors, contact time, initial concentration, temperature, and pH value on the adsorption capacity of RB were studied. The adsorption equilibrium data displayed a better fitting to the Langmuir isotherm model than the Freundlich model and the adsorption kinetics fitted well with the pseudo-second-order kinetic model. The recycle experiments displayed that the capacity recovery was still higher than 95% after four cycles. Theses polymers are promising to be the adsorbents for capturing CO2 and removing RB. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 136, 48572. 相似文献
69.
《Zeolites》1989,9(3):253-256
HZSM-5 appears to be ferroelastic. Application of a uniaxial mechanical stress during the orthorhombic/monoclinic transition of zeoltie HZSM-5 changes the population of the monoclinic twin domains. The volume fraction of one of the twin mates is changed from 0.5 (before application of mechanical stress) to 0.06 in the crystal studied. 相似文献
70.
用苯酚为封闭剂,对TDI(80%2,4-二异氰酸酯甲苯+20%2,6-二异氰酸酯甲苯)进行了封闭。研究了不同因素对PTDI(封闭的TDI)脱封温度的影响,用二月桂酸二丁基锡为催化剂,有效地降低了PTDI的脱封温度。以PTDI为交联剂制备了聚氨酯胶片,测试了所得聚氨酯胶片的拉伸强度、断裂伸长率、撕裂强度、邵氏硬度等性能,讨论了硫化温度、硫化时间、催化剂用量等各种因素对聚氨酯胶片性能的影响。 相似文献