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971.
972.
伴随着新媒体时代的全面来临,各类智能终端设备进驻千家万户,人们的生活方式和思维方式已受到了极大的影响和改变。本文以自媒体时代为背景,分析了当前高校大学生目前使用自媒体媒介的现状,结合自媒体媒介的优缺点,探讨了当前高校师生关系存在的问题,并根据目前存在的问题,提出了构建自媒体时代和谐师生关系的几条对策。 相似文献
973.
中国传统教育思想内涵深厚、源远流长,依然需要今天的教育研究者不断发现其现代价值,并运用到当代教育的改革发展实践中。本文探究了中国传统教育思想对通识教育发展的意义,分析了当代应用型大学通识教育的缺失及其原因,并应用中国传统教育理念对通识教育的目标、课程体系的完整性及课程设计中合作学习的设计三个方面提出了发展建议。 相似文献
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975.
Wei Ren Tang Li Qiuzhi Qu Bin Wang Lin Li Desheng Lü Weibiao Chen Liang Liu 《国家科学评论(英文版)》2020,7(12):1828
Atomic clocks with cold atoms play important roles in the field of fundamental physics as well as primary frequency standards. Operating such cold atom clocks in space paves the way for further exploration in fundamental physics, for example dark matter and general relativity. We developed a space cold atom clock (SCAC), which was launched into orbit with the Space Lab TG-2 in 2016. Before it deorbited with TG-2 in 2019, the SCAC had been working continuously for almost 3 years. During the period in orbit, many scientific experiments and engineering tests were performed. In this article, we summarize the principle, development and in-orbit results. These works provide the basis for construction of a space-borne time-frequency system in deep space. 相似文献
976.
977.
Shuyu Xiao Yaming Jin Xiaomei Lu Sang-Wook Cheong Jiangyu Li Yang Li Fengzhen Huang Jinsong Zhu 《国家科学评论(英文版)》2020,7(2):278
Ferroelectric domain walls differ from domains not only in their crystalline and discrete symmetry, but also in their electronic, magnetic, and mechanical properties. Although domain walls provide a degree of freedom to regulate the physical properties at the nanoscale, the relatively lower controllability prevents their practical applications in nano-devices. In this work, with the advantages of 3D domain configuration detection based on piezoresponse force microscopy, we find that the mobility of three types of domain walls (tail-to-tail, head-to-tail, head-to-head) in (001) BiFeO3 films varies with the applied electrical field. Under low voltages, head-to-tail domain walls are more mobile than other domain walls, while, under high voltages, tail-to-tail domain walls become rather active and possess relatively long average lengths. This is due to the high nucleation energy and relatively low growth energy for charged domain walls. Finally, we demonstrate the manipulation of domain walls through successive electric writings, resulting in well-aligned conduction paths as designed, paving the way for their application in advanced spintronic, memory and communication nano-devices. 相似文献
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979.
Ningsi Zhang Xin Wang Jianyong Feng Huiting Huang Yongsheng Guo Zhaosheng Li Zhigang Zou 《国家科学评论(英文版)》2020,7(6):1059
Although β-Fe2O3 has a high theoretical solar-to-hydrogen efficiency because of its narrow band gap, the study of β-Fe2O3 photoanodes for water splitting is elusive as a result of their metastable nature. Raman identification of β-Fe2O3 is theoretically and experimentally investigated in this study for the first time, thus clarifying the debate about its Raman spectrum in the literature. Phase transformation of β-Fe2O3 to α-Fe2O3 was found to potentially take place under laser and electron irradiation as well as annealing. Herein, phase transformation of β-Fe2O3 to α-Fe2O3 was inhibited by introduction of Zr doping, and β-Fe2O3 was found to withstand a higher annealing temperature without any phase transformation. The solar water splitting photocurrent of the Zr-doped β-Fe2O3 photoanode was increased by 500% compared to that of the pure β-Fe2O3 photoanode. Additionally, Zr-doped β-Fe2O3 exhibited very good stability during the process of solar water splitting. These results indicate that by improving its thermal stability, metastable β-Fe2O3 film is a promising photoanode for solar water splitting. 相似文献
980.