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排序方式: 共有680条查询结果,搜索用时 31 毫秒
81.
Luo Manlelan Sliva Andrey P. Hu Renzhi Goncharov Aleksei L. Karpovich Dragunov Viktor Trushnikov Dmitriy N. Pang Shengyong 《Metallurgical and Materials Transactions A》2022,53(9):3369-3380
Metallurgical and Materials Transactions A - Low-frequency scanning electron beam welding (SEBW) is recently recognized as a possible control method for preventing the top concavity behavior in... 相似文献
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Pavel Diko Renáta Pagáčová Katarína Zmorayová Veronika Kuchárová Liudmila Vojtková Vitaliy Antal Viktor Kavečanský 《Journal of the American Ceramic Society》2021,104(2):740-752
Barium cerate (BaCeO3) is one of the possible additions to bulk YBa2Cu3O7 single-grain superconductors to suppress the growth of Y2BaCuO5 (Y211) particles. This paper investigates the synthesis of barium cerate powder and its use in YBa2Cu3O7 bulk superconductors. Crystalline barium cerate was synthesized by solid-state reaction, by co-precipitation of oxalates and by sol-gel method. Final calcination was held in air or in vacuum. It is shown that the most efficient in refining Y211 is nanocrystalline barium cerate prepared by sol-gel method calcined in vacuum. The effective refinement of Y211 particles occurred over the entire interval of nanocrystalline BaCeO3 addition from 0.38 to 1.90 wt%. The optimal concentration of nanosize barium cerate was determined, microstructure and superconducting properties were characterized. The effect of Y211 content on trapped field in YBCO bulks with addition of nanocrystalline barium cerate is shown. 相似文献
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Bone Repair: High‐Performance Thiol–Ene Composites Unveil a New Era of Adhesives Suited for Bone Repair (Adv. Funct. Mater. 26/2018)
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Felix Lang Oleksandra Shargaieva Viktor V. Brus Heinz C. Neitzert Jörg Rappich Norbert H. Nickel 《Advanced materials (Deerfield Beach, Fla.)》2018,30(3)
Organic–inorganic perovskites are well suited for optoelectronic applications. In particular, perovskite single and perovskite tandem solar cells with silicon are close to their market entry. Despite their swift rise in efficiency to more than 21%, solar cell lifetimes are way below the needed 25 years. In fact, comparison of the time when the device performance has degraded to 80% of its initial value (T80 lifetime) of numerous solar cells throughout the literature reveals a strongly reduced stability under illumination. Herein, the various detrimental effects are discussed. Most notably, moisture‐ and heat‐related degradation can be mitigated easily by now. Recently, however, several photoinduced degradation mechanisms have been observed. Under illumination, mixed perovskites tend to phase segregate, while, further, oxygen catalyzes deprotonation of the organic cations. Additionally, during illumination photogenerated charge can be trapped in the N? H antibonding orbitals causing dissociation of the organic cation. On the other hand, organic–inorganic perovskites exhibit a high radiation hardness that is superior to crystalline silicon. Here, the proposed degradation mechanisms reported in the literature are thoroughly reviewed and the microscopic mechanisms and their implications for solar cells are discussed. 相似文献
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