There is a large surface-groundwater exchange downstream ofwastewater treatment plants(WWTPs),and antibiotics upstream may influence sites downstream of rivers.Thus,samples from 9 effluent-receiving urban rivers(ERURs...There is a large surface-groundwater exchange downstream ofwastewater treatment plants(WWTPs),and antibiotics upstream may influence sites downstream of rivers.Thus,samples from 9 effluent-receiving urban rivers(ERURs)and 12 groundwater sites were collected in Shijiazhuang City in December 2020 and April 2021.For ERURs,8 out of 13 target quinolone antibiotics(QNs)were detected,and the total concentration of QNs in December and April were 100.6-4,398 ng/L and 8.02–2,476 ng/L,respectively.For groundwater,all target QNs were detected,and the total QNs concentration was 1.09–23.03 ng/L for December and 4.54–170.3 ng/L for April.The distribution of QNs was dissimilar between ERURs and groundwater.Most QN concentrations were weakly correlated with land use types in the system.The results of a positive matrix factorization model(PMF)indicated four potential sources of QNs in both ERURs and groundwater,and WWTP effluents were the main source of QNs.From December to April,the contribution of WWTP effluents and agricultural emissions increased,while livestock activities decreased.Singular value decomposition(SVD)results showed that the spatial variation of most QNs was mainly contributed by sites downstream(7.09%-88.86%)of ERURs.Then,a new method that combined the results of SVD and PMF was developed for a specific-source-site risk quotient(SRQ),and the SRQ for QNs was at high level,especially for the sites downstream of WWTPs.Regarding temporal variation,the SRQ for WWTP effluents,aquaculture,and agricultural emissions increased.Therefore,in order to control the antibiotic pollution,more attention should be paid to WWTP effluents,aquaculture,and agricultural emission sources for the benefit of sites downstream of WWTPs.展开更多
Recent progress in the research of radical anion ligands and their complexes with metals were summarized in this review.Radical anions were sorted into several types including iminosemiquinonate and iminoquinonate rad...Recent progress in the research of radical anion ligands and their complexes with metals were summarized in this review.Radical anions were sorted into several types including iminosemiquinonate and iminoquinonate radical,nitroxide radical,heterocycle radical etc.Structural characteristics and properties of the corresponding complexes were introduced.The complexes exhibited novel properties and possibility for applications in organic magnetic materials and transition metal catalysis.展开更多
基金This work was supported by the Natural Science Foundation of Hebei Province(No.D2019208152)the Natural Science Foundation of Higher Education Institutions of Hebei Province(No.ZD2021046).
文摘There is a large surface-groundwater exchange downstream ofwastewater treatment plants(WWTPs),and antibiotics upstream may influence sites downstream of rivers.Thus,samples from 9 effluent-receiving urban rivers(ERURs)and 12 groundwater sites were collected in Shijiazhuang City in December 2020 and April 2021.For ERURs,8 out of 13 target quinolone antibiotics(QNs)were detected,and the total concentration of QNs in December and April were 100.6-4,398 ng/L and 8.02–2,476 ng/L,respectively.For groundwater,all target QNs were detected,and the total QNs concentration was 1.09–23.03 ng/L for December and 4.54–170.3 ng/L for April.The distribution of QNs was dissimilar between ERURs and groundwater.Most QN concentrations were weakly correlated with land use types in the system.The results of a positive matrix factorization model(PMF)indicated four potential sources of QNs in both ERURs and groundwater,and WWTP effluents were the main source of QNs.From December to April,the contribution of WWTP effluents and agricultural emissions increased,while livestock activities decreased.Singular value decomposition(SVD)results showed that the spatial variation of most QNs was mainly contributed by sites downstream(7.09%-88.86%)of ERURs.Then,a new method that combined the results of SVD and PMF was developed for a specific-source-site risk quotient(SRQ),and the SRQ for QNs was at high level,especially for the sites downstream of WWTPs.Regarding temporal variation,the SRQ for WWTP effluents,aquaculture,and agricultural emissions increased.Therefore,in order to control the antibiotic pollution,more attention should be paid to WWTP effluents,aquaculture,and agricultural emission sources for the benefit of sites downstream of WWTPs.
基金supported by the National Natural Science Foundation of China(20972025,U1362110)PetroChina Innovation Foundation(2013D-5006-0503)+2 种基金Scientific Research Foundation for the Returned Overseas Chinese Scholars,Program for New Century Excellent Talents in University(NCET-07-0142)Heilongjiang Province(41417837-8-08016)Department of Education of Heilongjiang Province(1154H14,1154G53)
文摘Recent progress in the research of radical anion ligands and their complexes with metals were summarized in this review.Radical anions were sorted into several types including iminosemiquinonate and iminoquinonate radical,nitroxide radical,heterocycle radical etc.Structural characteristics and properties of the corresponding complexes were introduced.The complexes exhibited novel properties and possibility for applications in organic magnetic materials and transition metal catalysis.
