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861.
This study, based on data collected from a representative sample of adults in the United States, explores the social cognitive variables that motivated Americans to validate rumours on social media about Hurricanes Harvey and Irma, both of which struck in August/September 2017. The results indicate that risk perception and negative emotions are positively related to systematic processing of relevant risk information, and that systematic processing is significantly related to rumour validation through search engines such as Google. In contrast, trust in information about the hurricane is significantly related to validation through official sources, such as FEMA (Federal Emergency Management Agency), and major news outlets such as The New York Times. Trust in information is also significantly related to systematic processing of risk information. The findings of this study suggest that ordinary citizens may be motivated to validate rumours on social media, which is an increasingly important issue in contemporary societies. 相似文献
862.
Different nutrient media experimentally were N, P and Fe-limited conditions and a serial of diluted BGll media. The cell change of morphology and life history, cell number, cell color and cell area of Microcystis were analyzed quantitatively. First, the effects of nitrogen, phosphorus and iron depletion were distinctively different. Phosphorus and iron depletion caused more special division cells,slowly growth increasing, the easier change of bigger cell area. Second, the nitrogen and iron depletion could make the color of alga from green to brown. Finally, according to the resource competition and Monod equation, Microcystis kinetics of phosphorus and iron were also examined. Ks and μmax of phosphorus absorption were 0.0352 μmol/L, 0.493 d^-1 respectively; iron absorption: 0.00323 μmol/L, 0.483d^-1. In a word, some evidences of the Microcystis bloom dominance in certain nutrient conditions were indicated in the experiments. The dominances were determined as the reviving under the adverse circumstances through the special division, the various nitrogen resources,and the lower kinetics of phosphorus and iron than that of most of other algae. The conclusions provided the scientific basis for preventing and managing Microcystis bloom in freshwater. 相似文献
863.
Ammonium removal by modified zeolite from municipal wastewater 总被引:4,自引:0,他引:4
Ammonium removal by modified zeolite, H-form and Na-form zeolite, were examined by batch-type methods. The adsorption of ammonium on modified zeolite was exothermic process. The saturation adsorption capacity of ammonium on H-form and Na-form zeolite were 21.23 and 41.1.5 mg/g, respectively. After ten times adsorption-desorption-readsorption cycles the standard deviations of H-form and Na-form zeolite were 6.34% and 6.59%. The zeolite adsorption process has proved cost effective and practical in reducing ammonium by H-form and Na-form zeolite in municipal wastewater from concentration 27.68 mg/L to 2.80 mg/L and 5.91 mg/L. 相似文献
864.
“双碳”愿景下微观企业层面的环境责任受到更多关注。本文运用Python获取2014—2019年中国A股上市工业企业数据,分析了异质性企业环境责任对碳绩效的影响,探讨了媒体关注和环境规制在其中的联合调节效应。研究表明:履行前瞻型环境责任和反应型环境责任均对企业碳绩效有显著的增进作用;媒体关注可以正向调节前瞻型企业环境责任和碳绩效的关系,但在反应型企业环境责任与碳绩效间的调节作用不显著。进一步研究发现:环境规制与媒体关注在反应型企业环境责任和碳绩效间产生正向联合调节作用,而在前瞻型环境责任与碳绩效间的联合调节作用不显著。研究结果支持了政府和媒体对企业环境责任的正式和非正式治理效果,进而提高了企业碳绩效的作用逻辑,拓展了对企业碳绩效影响因素以及异质性企业环境责任的理论研究,将环境治理他治和自治相结合,为多元环境治理主体协同联动推进“双碳”目标顺利实现提供新思路和参考证据。 相似文献
865.
ZnCo-LDHs改性人工湿地沸石基质对城市污水的净化效果 总被引:1,自引:0,他引:1
选取常用的垂直流人工湿地沸石基质,采用金属离子物质的量比(Zn~(2+)∶Co~(3+))为2∶1在碱性环境下共沉淀生成ZnCo-LDHs,并覆膜于沸石基质表面,分析了改性前后基质的物化特性;构建模拟垂直流人工湿地基质试验柱,对改性前后2种沸石基质对城市污水的净化效果进行了研究。结果表明:Zn Co-LDHs覆膜改性沸石基质的方法是可行的;ZnCo-LDHs覆膜于基质表面,改变了原始沸石基质的物理化学特性,促进了基质对污染物的物理拦截和物化吸附作用;ZnCo-LDHs改性基质对城市污水中CODCr、氨氮、TP的净化效果均有所提高,其平均去除率分别达到了76%、63%和88%。 相似文献
866.
867.