Reported here is the synthesis of a new macrocycle bearing anionic carboxylate groups with water-soluble aggregation-induced emission(AIE).The water-soluble macrocycle without typical AIE luminogens is constructed based on the building block of benzothiadiazole.It exhibits a remarkable AIE effect.This watersoluble macrocycle can selectively bind different types of biogenic amines in aqueous media with the tightest binding towards spermine.The fluorescence enhancement induced by supramolecular encapsulation is used to detect spermine.
As a vital type of light-absorbing aerosol,brown carbon(BrC)presents inherent associations with atmospheric photochemistry and climate change.However,the understanding of the chemical and optical properties of BrC is limited,especially in some resource-dependent cities with long heating periods in northwest China.This study showed that the annual average abundances of Water-soluble BrC(WS-BrC)were 9.33±7.42 and 8.69±6.29μg/m^(3)in Baotou and Wuhai and the concentrations,absorption coefficient(Abs_(365)),and mass absorption efficiency(MAE365)of WS-BrC presented significant seasonal patterns,with high values in the heating season and low values in the non-heating season;while showing opposite seasonal trends for the Absorption Angstr?m exponent(AAE_(300-400)).Comparatively,the levels of WS-BrC in developing regions(such as cities in Asia)were higher than those in developed regions(such as cities in Europe and Australia),indicating the significant differences in energy consumption in these regions.By combining fluorescence excitation-emission matrix(EEM)spectra with the parallel factor(PARAFAC)model,humic-like(C1 and C2)and proteinlike(C3)substances were identified,and accounted for 61.40%±4.66%and 38.6%±3.78%at Baotou,and 60.33%±6.29%and 39.67%±4.17%at Wuhai,respectively.The results of source apportionment suggested that the potential source regions of WS-BrC varied in heating vs.non-heating seasons and that the properties of WS-BrC significantly depended on primary emissions(e.g.,combustion emissions)and secondary formation.
Haoji WangYue SuYangzheng LiuFei XieXingjun ZhouRuihong YuChangwei LüJiang He
Water-soluble chitosan(WSC)has been studied for its ability to mobilize soil Pb and promote the phytoremediation by Hylotelephium spectabile in Pb-contaminated fields.We aimed to clarify the internal mechanism by which wSC impacts phytoremediation by examining plant growth and Pb accumulation performance of H.spectabile as well as the Pb form,functional groups,and mineral phases of Pb-contaminated soil.WSC effectively decreased soil pH and activated Pb migration in rhizosphere soils,with a considerable increase in water-soluble and acid-extractable Pb by 29%-102%and 9%-65%,respectively,and a clear decreasing trend in reducible and oxidizable Pb.Fourier-transform infrared spectroscopy revealed a significant increase in amino and hydroxyl groups in the soil generated by WSC.The coordination of Pb with amino and hydroxyl groups may play an important role in the formation of Pb complexes and activation of Pb in soil.In field trials,the application of WSC significantly increased Pb accumulation in H.spectabile by 125.44%,reaching 92 g/hm^(2).Moreover,the organic matter and nitrogen in the soils were increased by WSc,which improved the growth conditions of H.spectabile.No obvious growth inhibition was observed in either the pot or field trials.Therefore,WSC is a promising chelating agent for mobilizing Pb in soil.Additionally,WSC can be potentially used to boost H.spectabil-mediated phytoremediation of Pb-contaminatedfarmland.
