Air pollutants can be transported to the pristine regions such as the Tibetan Plateau,by monsoon and stratospheric intrusion.The Tibetan Plateau region has limited local anthropogenic emissions,while this region is in...Air pollutants can be transported to the pristine regions such as the Tibetan Plateau,by monsoon and stratospheric intrusion.The Tibetan Plateau region has limited local anthropogenic emissions,while this region is influenced strongly by transport of heavy emissions mainly from South Asia.We conducted a comprehensive study on various air pollutants (PM_(2.5),total gaseous mercury,and surface ozone) at Nam Co Station in the inland Tibetan Plateau.Monthly mean PM_(2.5)concentration at Nam Co peaked in April before monsoon season,and decreased during the whole monsoon season (June–September).Monthly mean total gaseous mercury concentrations at Nam Co peaked in July and were in high levels during monsoon season.The Indian summer monsoon acted as a facilitator for transporting gaseous pollutants (total gaseous mercury) but a suppressor for particulate pollutants (PM_(2.5)) during the monsoon season.Different from both PM_(2.5)and total gaseous mercury variabilities,surface ozone concentrations at Nam Co are primarily attributed to stratospheric intrusion of ozone and peaked in May.The effects of the Indian summer monsoon and stratospheric intrusion on air pollutants in the inland Tibetan Plateau are complex and require further studies.展开更多
Three 4.8 nm isostructural{M_(72)}(M=Co^(Ⅱ) for CIAC-128,Ni^(Ⅱ) for CIAC-129,Fe^(Ⅱ) for CIAC-130) metal-organic polyhedra(MOPs) are constructed by eighteen M_(4)-p-tert-butylthiacalix[4]arene (M_(4)-TC4A) units bri...Three 4.8 nm isostructural{M_(72)}(M=Co^(Ⅱ) for CIAC-128,Ni^(Ⅱ) for CIAC-129,Fe^(Ⅱ) for CIAC-130) metal-organic polyhedra(MOPs) are constructed by eighteen M_(4)-p-tert-butylthiacalix[4]arene (M_(4)-TC4A) units bridged via sixteen four-connected 5,5′-(1H-1,2,4-triazole-3,5-diyl) diisophthalic acid (H_(4)TADIPA) linkers.These MOPs are featured with a rarely reported concave coordination cage,which can be simplified as a squeezed double-decker hexagonal prism pressed from the top and bottom hexagonal faces.Furthermore,CIAC-128,CIAC-129 and CIAC-130 are the highest nuclearity discrete clusters of Co,Ni and Fe reported so far.CIAC-128 has higher separation selectivity of C_(3)H_(8) than CH_(4) under ambient conditions,and also exhibits separation selectivity for C_(2)H_(6)/CH_(4),C_(2)H_(2)/CH_(4),and C_(2)H_(4)/CH_(4).In addition,CIAC-128 can provide the cavity for the confined synthesis of noble metal nanoclusters such as Pd nanoclusters and the resulting Pd@CIAC-128 hybrids show higher electrocatalytic activity than commercial Pt/C towards hydrogen evolution reaction (HER).展开更多
基金This study was supported by the Strategic Priority Research Program(A)of the Chinese Academy of Sciences(XDA20040501)the National Natural Science Foundation of China(41907328)+3 种基金State Key Laboratory of Cryospheric Science(SKLCS-ZZ-2020)financial support from the Chinese Academy of Sciences"Light of West China"Programfinancial support from the Youth Innovation Promotion Association of CAS(2016070)the support provided by the Institute for Advanced Sustainability Studies(IASS),which is funded by the German Federal Ministry for Education and Research(BMBF)and the Brandenburg Ministry for Science,Research and Culture(MWFK)。
文摘Air pollutants can be transported to the pristine regions such as the Tibetan Plateau,by monsoon and stratospheric intrusion.The Tibetan Plateau region has limited local anthropogenic emissions,while this region is influenced strongly by transport of heavy emissions mainly from South Asia.We conducted a comprehensive study on various air pollutants (PM_(2.5),total gaseous mercury,and surface ozone) at Nam Co Station in the inland Tibetan Plateau.Monthly mean PM_(2.5)concentration at Nam Co peaked in April before monsoon season,and decreased during the whole monsoon season (June–September).Monthly mean total gaseous mercury concentrations at Nam Co peaked in July and were in high levels during monsoon season.The Indian summer monsoon acted as a facilitator for transporting gaseous pollutants (total gaseous mercury) but a suppressor for particulate pollutants (PM_(2.5)) during the monsoon season.Different from both PM_(2.5)and total gaseous mercury variabilities,surface ozone concentrations at Nam Co are primarily attributed to stratospheric intrusion of ozone and peaked in May.The effects of the Indian summer monsoon and stratospheric intrusion on air pollutants in the inland Tibetan Plateau are complex and require further studies.
基金supported by the National Natural Science Foundation of China(21971233,21571172,51222404)。
文摘Three 4.8 nm isostructural{M_(72)}(M=Co^(Ⅱ) for CIAC-128,Ni^(Ⅱ) for CIAC-129,Fe^(Ⅱ) for CIAC-130) metal-organic polyhedra(MOPs) are constructed by eighteen M_(4)-p-tert-butylthiacalix[4]arene (M_(4)-TC4A) units bridged via sixteen four-connected 5,5′-(1H-1,2,4-triazole-3,5-diyl) diisophthalic acid (H_(4)TADIPA) linkers.These MOPs are featured with a rarely reported concave coordination cage,which can be simplified as a squeezed double-decker hexagonal prism pressed from the top and bottom hexagonal faces.Furthermore,CIAC-128,CIAC-129 and CIAC-130 are the highest nuclearity discrete clusters of Co,Ni and Fe reported so far.CIAC-128 has higher separation selectivity of C_(3)H_(8) than CH_(4) under ambient conditions,and also exhibits separation selectivity for C_(2)H_(6)/CH_(4),C_(2)H_(2)/CH_(4),and C_(2)H_(4)/CH_(4).In addition,CIAC-128 can provide the cavity for the confined synthesis of noble metal nanoclusters such as Pd nanoclusters and the resulting Pd@CIAC-128 hybrids show higher electrocatalytic activity than commercial Pt/C towards hydrogen evolution reaction (HER).
