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991.
Liang Xu Lei Su Hongjie Wang Hongfei Gao De Lu Kang Peng Min Niu Zhixin Cai 《Journal of the American Ceramic Society》2022,105(2):1548-1557
Thermal barrier coating materials with proper thermal expansion coefficient (TEC), low thermal conductivity, and good high-temperature stability are of great significance for their applications in next-generation turbine engines. Herein, we report a new class of high-entropy (La0.2Sm0.2Er0.2Yb0.2Y0.2)2CexO3+2x with different Ce4+ contents synthesized by a solid-state reaction method. They exhibit different crystal structures at different Ce4+ content, including a bixbyite single phase without Ce4+ doping (x = 0), bixbyite-fluorite dual-phase in the RE2O3-rich region (0 < x < 2), and fluorite single phase in the stoichiometric (x = 2) and CeO2-rich region (x > 2). The high-entropy (La0.2Sm0.2Er0.2Yb0.2Y0.2)2CexO3+2x exhibit tailorable TECs at a large range of 9.04 × 10–6–13.12 × 10–6 °C–1 and engineered low thermal conductivity of 1.79–2.63 W·m–1·K–1. They also possess good sintering resistance and high-temperature phase stability. These results reveal that the high-entropy (La0.2Sm0.2Er0.2Yb0.2Y0.2)2CexO3+2x are promising candidates for thermal barrier coating materials as well as thermally insulating materials and refractories. 相似文献
992.
Chao He Bin Du Juan Ma Hao Xiong Junjie Qian Mei Cai Anze Shui 《Journal of the American Ceramic Society》2022,105(5):3177-3188
Under the condition of constant thickness, improving the low-frequency sound absorption performance of conventional sound-absorbing materials is a challenging research topic. To address this issue, a new reduced graphene oxide/polyvinyl alcohol (RGO/PVA) porous composite ceramic was fabricated using freeze-drying and optimized by redesigning the internal connecting pores of porous ceramic matrixes with a reticular microstructure using RGO and PVA. The as-prepared porous structure showed significant enhancement in the low-frequency sound absorption band compared with pristine porous ceramics. In addition, the hybrid porous ceramics exhibited low thermal conductivity. These favorable properties indicate that the hybrid sound-absorbing ceramics have potential application prospects for noise reduction in the fields of construction and electrical and mechanical devices. 相似文献
993.
Haoyi Wang Delong Cai Zhihua Yang Xiaoming Duan Bingzhu Wang Bo Wang Daxin Li Dechang Jia Yu Zhou 《Journal of the American Ceramic Society》2022,105(5):3590-3600
A type of boron nitride–magnesium aluminum silicate (BN-MAS) composite ceramics was fabricated by hot-press sintering at different sintering temperatures. The relationship between the sintering temperature and microstructure was investigated by analyzing the interaction between hexagonal boron nitride (h-BN) and the MAS phase. The main MAS phase in the composite ceramics is the α-cordierite phase at a sintering temperature of 1300°C. At temperatures above 1400°C, the inhibitory effect of h-BN on the crystallization of the MAS system is significant, and MAS mainly exists in the form of an amorphous phase. The composite sintered at 1700°C exhibited the highest bending strength of 218MPa. h-BN and MAS were co-enhanced. MAS can be used as an effective liquid-phase sintering aid to assist in the sintering of h-BN, whereas h-BN can absorb the fracture energy of the composite ceramics through the pull-out and bridging effect of the particles. 相似文献
994.
Junjie Qian Bin Du Chao He Mei Cai Xinrong Zhong Hao Xiong Shenghui Zeng Anze Shui 《Journal of the American Ceramic Society》2022,105(5):3456-3468
The hierarchical SiOC/SiCnws/CF composites (A/B/C structure) were designed via precursor infiltration and pyrolysis process. The SiOC ceramics served as the wave-transparent characteristic materials to adjust the impedance matching. Herein, the in situ growth of SiCnws not only was used for the absorber but served as the reinforcement of SiOC matrix composites. In detail, the SiOC/SiCnws/CF-1200°C-2 exhibits excellent electromagnetic absorption performance with minimum reflection loss of −46 dB at 14.4 GHz with the thickness of 1.6 mm, and its effective absorption band reaches 4.3 GHz. Its compressive strength reaches 8.69 and 16.41 MPa in z and x/y directions, separately. This contribution has a guidance for the application of carbon fiber/ceramics matrix composites in harsh environment. 相似文献
995.
Dr. Lei Chen Ying Yang Yuanliang Zhang Kecheng Li Prof. Hongmin Cai Prof. Hongwei Wang Dr. Qian Zhao 《Chembiochem : a European journal of chemical biology》2022,23(8):e202100534
Small open reading frames (sORFs) are an important class of genes with less than 100 codons. They were historically annotated as noncoding or even junk sequences. In recent years, accumulating evidence suggests that sORFs could encode a considerable number of polypeptides, many of which play important roles in both physiology and disease pathology. However, it has been technically challenging to directly detect sORF-encoded peptides (SEPs). Here, we discuss the latest advances in methodologies for identifying SEPs with mass spectrometry, as well as the progress on functional studies of SEPs. 相似文献
996.
Silicon - In the production of multicrystalline silicon solar cell, diamond wire sawing method (DWS) is an important technique, which has already completely replaced multiwire slurry sawing (MWSS)... 相似文献
997.
998.
为提高生产效率、降低生产成本、快速判断混合溶剂芳脂比,研究了混合溶剂芳脂比与特定温度下密度的关系。实验结果表明,混合溶剂的芳脂比与其特定温度下的密度之间存在明显线性关系,且该线性关系对生产具有指导意义。 相似文献
999.
1000.