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A polyampholytic superabsorbent polymer (PASAP), sodium alginate-g-(polyacrylic acid-co-allyltrimethylammonium chloride) (SA-g-(PAA-co-PTM)), was prepared by free-radical graft copolymerization and characterized. The polymer exhibited pH-dependent swelling behaviors with extremely high swelling ratios, and was saline tolerant. The dye adsorption properties of SA-g-(PAA-co-PTM) were investigated using methylene blue (MB) as a cationic dye model. It was found that its dye adsorption capacity was significantly affected by the TM content in PASAP and pH of dye solution. The dye adsorption kinetics and isotherm obey the pseudo-second-order kinetic model and the Langmuir isotherm model, respectively, and the adsorption process is chemisorption in nature. In addition, SA-g-(PAA-co-PTM) exhibited high MB adsorption capacities in a wide pH range and reusability in at least five adsorption-desorption cycles, indicating its great application potentials as the adsorbent for dye removals from effluents.

The climate impact assessment and monthly and annual reports o£ surface meteorological observation of cities and counties were reviewed, and there were no records of lightning disasters in Shaoyang from 1978 to 2000. Since 2001, there have been few records of lightning disasters, with only about 10 times in various regions. In this paper, a total of 143 investigation reports on lightning accidents since 2002 were collected, and statistical analysis was conducted based on the loss, location of occurrence, damaged industries, and social impact. In particular, the temporal and spatial distribution characteristics of lightning in Shaoyang area have been clearly understood, and the main characteristics and laws of lightning accidents in Shaoyang area were revealed. The results showed that the most lightning accidents occurred in June, and no lightning accidents occurred in December. Dongkou, Long- hui, and Shaoyang urban areas were the lightning prone areas, and the impact of lightning on agriculture was the largest, followed by commerce. The prevention countermeasures of lightning disasters were proposed to provide reference for disaster prevention and reduction. [ABSTRACT FROM AUTHOR]