Pollution characteristics and quantitative source apportionment of heavy metals within a zinc smelting site by GIS-based PMF and APCS-MLR models.

The abandoned smelters present a substantial pollution threat to the nearby soil and groundwater. In this study, 63 surface soil samples were collected from a zinc smelter to quantitatively describe the pollution characteristics, ecological risks, and source apportionment of heavy metal(loid)s (HMs). The results revealed that the average contents of Zn, Cd, Pb, As, and Hg were 0.4, 12.2, 3.3, 5.3, and 12.7 times higher than the risk screening values of the construction sites, respectively. Notably, the smelter was accumulated heavily with Cd and Hg, and the contribution of Cd (0.38) and Hg (0.53) to ecological risk was 91.58%. ZZ3 and ZZ7 were the most polluted workshops, accounting for 25.7% and 35.0% of the pollution load and ecological risk, respectively. The influence of soil parent materials on pollution was minor compared to various workshops within the smelter. Combined with PMF, APCS-MLR and GIS analysis, four sources of HMs were identified: P1(25.5%) and A3(18.4%) were atmospheric deposition from the electric defogging workshop and surface runoff from the smelter; P2(32.7%) and A2(20.9%) were surface runoff of As-Pb foul acid; P3(14.5%) and A4(49.8%) were atmospheric deposition from the leach slag drying workshop; P4(27.3%) and A1(10.8%) were the smelting process of zinc products. This paper described the distribution characteristics and specific sources of HMs in different process workshops, providing a new perspective for the precise remediation of the smelter by determining the priority control factors.

More friends on SNS, more materialism? The moderating roles of self-esteem and social comparison orientation.

On social networking sites, users are continuously exposed to a variety of posts from the networked individuals. Such information may often influence recipients' perceptions of what is important and goal pursuits such as materialism. Even though several studies have examined the negative consequences of using social networking sites, less attention has been paid to the role of friends' number and its impact on people's life goal pursuits. This study aimed to investigate the dark side of online friends and explored why and when more friends in social networking sites would promote materialism. Based on a sample of 264 WeChat users, study 1 discovered that friends' number positively impacted materialism through extrinsic goal (i.e., wealth and status). Additionally, such association was moderated by social comparison orientation and self-esteem. Importantly, self-esteem buffers the detrimental effect of friends' number on materialism while social comparison orientation increases it. Study 2 further tested the causal relationship and showed that friends' number on SNS might become a signal to indicate materialism via an experiment. In conclusion, our findings add to the understanding of psychological processes regarding the dark side of online friends' number and render suggestions for developing positive personal value.