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In order to analyze the ecological risk of the heavy metals in road dust. The improved potential ecological risk index was established. In the improved method, the toxicity of different chemical speciations of heavy metals were considered. Since residual fraction of Cd are non-toxic in the improved method, the results of the improved method were much lower than the traditional method.The results showed that the total risks of 3# and 15# were medium risk. The highest risk appeared on14# with the value 337.49, which belonged to high risk, and the total risk of the other sampling sites were low risk. Therefore, 14# should be the primary control site. The improved method established in this study is more scientific.

Herein, a new floating porous graphite carbon monolith (FCM) was prepared using the graphite powder and peanut shells as the carbon skeleton and using FAC and sepiolite as the swelling agent. The multi-hierarchical porous FCMs were obtained by two-step acid activation method. The effects of the addition of biomass and phosphoric acid on the physical properties and pore structure of the prepared material were investigated. The FCM was combined with codoped titania to develop a new floating photocatalysts. The results showed an increase in the amount of biomass materials during FCM preparation increased the ratio of mesoporous structure in the products. In addition, a high micropore volume ratio and the strongest adsorption effect were achieved by optimizing the phosphoric acid impregnation ratio. After process optimization, the densities of the prepared FCMs ranged between 0.75 and 0.89 g/cm3, and the specific surface area and diameter range of the large pores of the material were 104.5 m2/g and 3-50 μm, respectively. Moreover, the new floating catalysts displayed the excellent photocatalytic properties and recyclability performance.