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Preparing for back-to-school is essential, and it is also complicated because it involves different groups of people, and they have different needs. Pandemics, like COVID-19, make the situation even more difficult. Better preparation during a pandemic needs a comprehensive understanding of the situation. However, few studies have provided such information, especially during a pandemic. Furthermore, traditional research methods can hardly address the problems. This paper used text mining approaches to interpret open Twitter discussions on back-to-school preparation during COVID-19 and generated an inclusive insight into the preparation. Specifically, we collected 26,219 related tweets and analyzed the user profile descriptions to determine who was involved in the preparation. We also examined the most frequently retweeted tweets and conducted a topic modeling analysis to find people's concerns. Our research provides a holistic view of preparation for back-to-school during the pandemic, and it could help better prepare for back-to-school in the future pandemic.

The paper delves into the historical development of Taoism, analyzing its rise and fall across various Chinese dynasties. It begins with the Eastern Han dynasty, emphasizing Zhang Ling’s role in establishing Taoism as a significant religious force. The paper highlights the strategic expansion of Taoist influence under Zhang Lu in Sichuan. During the South North Dynasty, the focus shifts to Tao Hongjing’s efforts in integrating Taoist, Buddhist, and Confucian ideas, thereby creating a comprehensive deity system. The contributions of Ge Hong, especially in alchemy and the concept of ’inner alchemy’, are noted in the context of the Danding School. The peak of ancient Taoism is traced back to the Song and Yuan dynasties, underscoring the pivotal support of emperors and the roles of figures like Zhang Zhengsui and Zhang Jixian in promoting Taoism. However, the Ming and Qing dynasties saw Taoism’s decline due to the suppression of religious practices and its reduction to a mere cultural aspect for the royal family and aristocracy. The paper concludes by proposing a future path for Taoism, emphasizing the need for adaptation to modern society. It suggests that Taoism should lower barriers to entry and increase its relevance to contemporary life, learning from other religions like Christianity, to sustain its growth and significance in the modern era.

Two-dimensional (2D) van der Waals heterostructures (vdWHs) received intensive interest due to their amazing physical properties and broad applications in fields such as ultrasensitive sensors, transistors, and solar cells. Although remarkable progresses were achieved for the synthesis of 2D vdWHs, great challenges still remain for the easy preparation of 2D vdWHs because of the weak interlayer coupling. As a type of 2D semiconductor, the 2D SnSe film is particularly appealing for optoelectronic and thermoelectric devices because of its high thermoelectric and optoelectronic performance. However, the easy preparation of large-area and high-quality 2D SnSe films remains a great challenge. In this work, we proposed an approach to regulate the preparation of high-quality 2D vdWHs, which employed the polarization field of substrate as a key factor to control the diffusion barriers of the adsorbed Sn and Se atoms. Hexagonally stacking α-In2Se3 was selected as such polarized substrate because this substrate exhibits out-of-plane ferroelectricity with upward or downward polarized states at room temperature, and the two degenerated polarized states can be easily switched by applying an external electric field. It was revealed that the polarization field of α-In2Se3 can substantially influence the diffusion behavior of Sn and Se atoms on polarized α-In2Se3 substrate. So, the film growth property of SnSe film is sensitive to the polarization direction of In2Se3 substrate. Our research provides an ideal method to explore the possibility of building 2D functional nanoelectronic devices. [ABSTRACT FROM AUTHOR]

Over the years, Bi2Te3-based alloys have garnered considerable recognition as exceptional thermoelectric materials. Researchers have diligently pursued avenues to enhance the properties of these materials, with a primary focus on reducing thermal conductivity while maintaining optimal electrical performance. Nonetheless, achieving this delicate balance has proven to be a formidable challenge. In this study, we present a novel synergistic optimization approach that entails manipulating the grain refinement and porous structure of the material through precise adjustments in cooling rate and relief temperature during the direct current hot pressing process. By meticulously controlling these parameters, we successfully engineered a multiscale microstructure that effectively promotes phonon scattering. Simultaneously, we optimized carrier concentration. The outcomes of our investigation are truly remarkable, as we attained a peak zT value of approximately 1.23 at 325 K, accompanied by an outstanding average zTave of approximately 1.2 across the temperature range of 300–400 K in the 6.5% porosity-Bi0.35Sb1.65Te3 sample. These findings underscore the efficacy of the multiple synergies employed in our study. Moreover, our research provides a solid foundation for further exploration of complex micro structure modification techniques. [ABSTRACT FROM AUTHOR]