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90Sr has a long half-life, strong radioactivity, and high mobility. The removal of radioactive strontium from the water environment is of great significance to human safety and the sustainable development of nuclear energy. In this study, a two-dimensional rare earth phosphate K3Nd(PO4)2 efficiently captured Sr2+ ions in aqueous solutions. At room temperature, the adsorption isotherm, kinetics, and pH dependence experiments of K3Nd(PO4)2 for Sr2+ ions were examined (V/m = 1000 mL/g, 12 h contact time). The experimental results show that the maximum adsorption capacity of K3Nd(PO4)2 for Sr2+ (qmSr) was 42.35 mg/g. The removal efficiency for Sr2+ (RSr) was 87.47% within 24 h. It had a good affinity with Sr2+ ions in neutral or even high alkaline environments (distribution coefficient KdSr = 1.46 × 106 mL/g, RSr = 99.93%). The adsorption mechanism was attributed to the ion exchange between Sr2+ and K+ ions by batch adsorption experiments combined with multiple characterizations, including XPS, EDS, and PXRD. This is the first report of Sr2+ removal by ion exchange via rare earth phosphate materials with a two-dimensional structure. This work provides insight into the future development of rare earth phosphates as ion exchange materials for radionuclide remediation.

This study explores factors influencing the sharing behaviour of medical crowdfunding campaigns on mobile social media regarding retweeter and retweeted text features from the social influence perspective and verifies the moderating effect of potential supporter donations. Two scenario-based surveys of medical crowdfunding users are conducted in China. The first (524 samples) and second (510 samples) surveys emphasize scenarios without and with retweeted text, respectively. These surveys are tested by PLS-SEM and suggest that the credibility of retweeters and the strength of their relationship with supporters can positively promote potential supporters' sharing behaviour, regardless of whether retweeters provide retweeted text. Three features of retweeted text significantly influence medical crowdfunding sharing behaviour. Retweeted text can promote sharing behaviour among individuals. With retweeted text available, if potential supporters donate before sharing the campaign, then the influences of retweeter and retweeted text features can be increased.