Covering Covid-19 pandemic on short video platforms in China: a content analysis of Douyin accounts of people's daily and China daily

As a new form of social media, short videos have been deeply seated in Chinese life. In order to expand their influence, China's mainstream media also opened accounts on short video platforms, especially during the Covid-19 pandemic. They use short video platforms to report news, which play a key role in guiding public opinion and stabilising people's hearts. Based on the pandemic coverage of two of China's representative media, People's Daily and China Daily on Douyin platform, content analysis method is used to analyse the reporting frequency, video length, reporting content, reporting tendency, and user engagement, and compare the similarities and differences between the two media in the above five aspects. It was found that in terms of reporting frequency, the development trend of the two media is different, but they post roughly the same number of videos per day on average, and the number of videos released during the pandemic is higher than usual. In terms of video length, most of the videos of the two media are produced in a duration of one minute. China Daily produced more long videos than People's Daily. In terms of the reporting content, the two media are involved in 11 constructed categories, but the top four categories are different because of the different position. About the reporting tendency, People's Daily has strong subjective emotion, and China Daily reported more neutral news. As for user engagement, People's Daily did better in likes, comments and shares, although both posted more likes, comments and shares than usual during the pandemic

Experimental study on impermeability of Loess liner mixed with bentonite-HDTMA

Abstract Permeability tests are performed by using the flexible wall permeameter to study the influence of bentonite-HDTMA (hexadecyl trimethyl ammonium bromide) on the permeability performance of Loess as a lining material in the solid waste landfill. Results show, the impermeability of compacted Loess in the middle and lower reaches of the Yellow River in China does not meet the standard requirement as the landfill liner. The permeability of Loess mixed with more than 10% bentonite ratio is less than 1.0 × 10−7 cm·s−1. The permeability of Loess increases slightly after mixing a small amount of HDTMA. The impermeability of Loess mixed with some bentonite-HDTMA ratio still meet the standard requirement. The HDTMA may destroy the soil aggregate structure and increase the soil permeate channel. The SEMs show that the bentonite clay particle can fill the pores between Loess coarse particles and improve the impermeability performance of the material. The digital photos show that HDTMA can effectively resist the development of soil macro-cracks induced by wetting–drying cycles, better for liner to maintain good impermeability. On this basis, the relationship between the hydraulic conductivity of bentonite-HDTMA modified Loess and dry density is constructed. From this study, Loess can be used as a lining material for landfills, when mixed with bentonite/HDTMA at ratios of 10%/0% or 14%/2%