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To investigate the influence of the Hutuo River (North China) ecological water replenishment project on the hydrogeochemical processes of groundwater, 64 groundwater samples collected at different time intervals after four replenishment events, and four samples from the Middle Route of the South-to-North Water Diversion Project water, were analyzed for water chemistry. Hydrogeochemical methods such as the Piper diagram, chloride-alkalinity index, and ion correlation were employed to analyze the characteristics of groundwater chemical evolution through replenishment. The results demonstrated that the hydrochemical types of groundwater in the study area underwent significant changes during continuous replenishment in the Hutuo River region. During the initial replenishment period (October 2019), the dominant hydrochemical type of groundwater in the study area was Mg-Na-HCO3-SO4, whereas the dominant type in the Middle Route of the South-to-North Water Diversion Project water was Ca-Na-SO4-HCO3. As the replenishment continued, the hydrochemical types of groundwater in the study area evolved into Ca-Na-Mg-HCO3-SO4, Na-Ca-Mg-HCO3-SO4, and Ca-Na-Mg-SO4-HCO3. The groundwater experienced a dissolution of calcite, gypsum, nitratine, carbonate rocks, and gypsum, accompanied by dilution effects, resulting in reduced ion exchange as replenishment progressed. The input of the high quality Middle Route of South-to-North Water Diversion Project water effectively promoted groundwater quality improvement, leading to an overall decrease or stabilization of components other than Ca2+ in the groundwater. Water quality was assessed using the entropy water quality index, with indicators including Na+, SO42−, Cl−, pH, total dissolved solids, NO3−-N, NO2−-N, F−, Al, As, and Zn. The evaluation results showed that, except for one medium-quality water sample, the water quality of the other samples was suitable for drinking and domestic purposes during the early replenishment period. The Middle Route of the South-to-North Water Diversion Project exhibited excellent quality (Rank 1), and as replenishment progressed, all water samples demonstrated good quality by October 2020, with a gradual improvement. [ABSTRACT FROM AUTHOR]

In order to prolong the shelf life of roasted mutton and effectively maintain the quality of the mutton as well, edible films were prepared by blending chitosan, sodium carboxymethyl cellulose, sodium alginate and oregano essential oil as film forming matrix, glycerol as plasticizer and CaCl2 as crosslinking agent. The effects of the contents of chitosan, sodium carboxymethyl cellulose, sodium alginate and oregano essential oil on the properties of the films were studied by single factor test. Based on the single factor test, the basic formula of the films was optimized by response surface test. The results show that the thickness, tensile strength, elongation at break and light transmittability of the film are excellent when the addition of chitosan is 0.664 g/ (100 g), sodium carboxymethyl cellulose is 0.398 g/ (100 g), sodium alginate is 0.510 g/ (100 g) and oregano essential oil is 0.941 g/ (100 g). By applying the composite film to the preservation of roasted mutton, the preservation time of roasted mutton is increased by 3~4 d, which greatly inhibits the oxidation rate of lipid in roasted mutton, effectively prolonging the shelf life of roasted mutton and improving the preservation effect of roasted mutton. The research provides a theoretical basis for the study on the preservation application of meat and meat products. [ABSTRACT FROM AUTHOR]

River bank filtration (RBF) under human supervision has been applied for groundwater recharge. This study clarified the characteristics of water composition and its origins during the reservoir water recharge RBF. The groundwater samples were collected during four periods: pre-recharge (June 2018), early recharge (November 2018), intermediate recharge (May 2019), and late recharge (October 2019). Hydrogeochemical methods (Piper diagram, chlor-alkali index, and ion correlation) and principal component analysis (PCA) were used to analyze the chemical evolution of groundwater in the aforementioned periods. TDS concentration tended to increase in the later stage due to the aggravation of carbonate rock dissolution and cation exchange adsorption. Results demonstrated a small, temporary influence of reservoir water on groundwater, characterized as the Ca–Mg–HCO3–SO4 and Ca–Mg–SO4–HCO3 types, both before and after the recharge. The research on water chemistry changes under different mixing ratios depicts that the continuation of the recharge process promotes mineral dissolution. Rock dissolution was the primary environmental control factor of groundwater components during the recharge period. This strengthened the water–rock reaction and caused potential risk impacts such as the increase of nitrate. [ABSTRACT FROM AUTHOR]