Biotoxicity assessment results of environmental waters largely depend on the sample extraction protocols that enrich pollutants to meet the effect-trigger thresholds of bioassays.However,more chemical mixture does not...Biotoxicity assessment results of environmental waters largely depend on the sample extraction protocols that enrich pollutants to meet the effect-trigger thresholds of bioassays.However,more chemical mixture does not necessarily translate to higher combined biotoxicity.Thus,there is a need to establish the link between chemical extracting efficiency and biotoxicity outcome to standardize extraction methods for biotoxicity assessment of environmental waters.This study compares the performance of five different extraction phases in solid phase extraction(SPE),namely HLB,HLB+Coconut,C18 cartridge,C18 disk and Strata-X,and evaluated their chemical extracting efficiencies and biotoxicity outcomes.We quantitatively assessed cytotoxicity,acute toxicity,genotoxicity,estrogenic activity,and neurotoxicity of the extracts using in vitro bioassays and characterized the chemical extracting efficiencies of the SPE methods through chemical recoveries of 23 model compounds with different polarities and total organic carbon.Using Pareto ranking,we identified HLB+Coconut as the optimal SPE method,which exhibited the highest level of water sample biotoxicity and recovered the most chemicals in water samples.We found that the biotoxicity outcomes of the extracted water samples significantly and positively correlated with the chemical extracting efficiencies of the SPE methods.Moreover,we observed synchronous changing patterns in biotoxicity outcome and chemical extracting efficiencies in response to increasing sample volumes per cartridge(SVPC)during SPE.Our findings underscore that higher chemical extracting efficiency of SPE corresponds to higher biotoxicity outcome of environmental water samples,providing a scientific basis for standardization of SPE methods for adequate assessment of biotoxicities of environmental waters.展开更多
When the installation of cables and pipelines needs to go across rivers,bridges are usually adopted to support the cables and pipelines for crossing the rivers.The measure can make full use of the space resources and ...When the installation of cables and pipelines needs to go across rivers,bridges are usually adopted to support the cables and pipelines for crossing the rivers.The measure can make full use of the space resources and have no effect on the flow pattern of rivers.For this reason,analysis on the structural-type design of a large-span steel truss bridge specially used for cables has been performed.The numerical results indicate that the stayed-cable bridge with steel truss beam and concrete main tower has better performance and improved structural type caparisoned with that of the beam and arch bridges,and the construction of the major beam can be without the temporary support.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52025102,52192682,51908276)the Excellent Research Program of Nanjing University(No.ZYJH005)the Fundamental Research Funds for the Central Universities(No.0211/14380200)。
文摘Biotoxicity assessment results of environmental waters largely depend on the sample extraction protocols that enrich pollutants to meet the effect-trigger thresholds of bioassays.However,more chemical mixture does not necessarily translate to higher combined biotoxicity.Thus,there is a need to establish the link between chemical extracting efficiency and biotoxicity outcome to standardize extraction methods for biotoxicity assessment of environmental waters.This study compares the performance of five different extraction phases in solid phase extraction(SPE),namely HLB,HLB+Coconut,C18 cartridge,C18 disk and Strata-X,and evaluated their chemical extracting efficiencies and biotoxicity outcomes.We quantitatively assessed cytotoxicity,acute toxicity,genotoxicity,estrogenic activity,and neurotoxicity of the extracts using in vitro bioassays and characterized the chemical extracting efficiencies of the SPE methods through chemical recoveries of 23 model compounds with different polarities and total organic carbon.Using Pareto ranking,we identified HLB+Coconut as the optimal SPE method,which exhibited the highest level of water sample biotoxicity and recovered the most chemicals in water samples.We found that the biotoxicity outcomes of the extracted water samples significantly and positively correlated with the chemical extracting efficiencies of the SPE methods.Moreover,we observed synchronous changing patterns in biotoxicity outcome and chemical extracting efficiencies in response to increasing sample volumes per cartridge(SVPC)during SPE.Our findings underscore that higher chemical extracting efficiency of SPE corresponds to higher biotoxicity outcome of environmental water samples,providing a scientific basis for standardization of SPE methods for adequate assessment of biotoxicities of environmental waters.
文摘When the installation of cables and pipelines needs to go across rivers,bridges are usually adopted to support the cables and pipelines for crossing the rivers.The measure can make full use of the space resources and have no effect on the flow pattern of rivers.For this reason,analysis on the structural-type design of a large-span steel truss bridge specially used for cables has been performed.The numerical results indicate that the stayed-cable bridge with steel truss beam and concrete main tower has better performance and improved structural type caparisoned with that of the beam and arch bridges,and the construction of the major beam can be without the temporary support.
