Assessing the impact of anthropogenic volatile organic compounds(VOCs)on ozone(O_(3))formation is vital for themanagement of emission reduction and pollution control.Continuousmeasurement of O_(3)and the major precurs...Assessing the impact of anthropogenic volatile organic compounds(VOCs)on ozone(O_(3))formation is vital for themanagement of emission reduction and pollution control.Continuousmeasurement of O_(3)and the major precursorswas conducted in a typical light industrial city in the YRD region from 1 May to 25 July in 2021.Alkanes were the most abundant VOC group,contributing to 55.0%of TVOCs concentration(56.43±21.10 ppb).OVOCs,aromatics,halides,alkenes,and alkynes contributed 18.7%,9.6%,9.3%,5.2%and 1.9%,respectively.The observational site shifted from a typical VOC control regime to a mixed regime from May to July,which can be explained by the significant increase of RO_(x)production,resulting in the transition of environment from NOx saturation to radical saturation with respect to O_(3)production.The optimal O_(3)control strategy should be dynamically changed depending on the transition of control regime.Under NOx saturation condition,minimizing the proportion of NOx in reduction could lead to better achievement of O_(3)alleviation.Under mixed control regime,the cut percentage gets the top priority for the effectiveness of O_(3)control.Five VOCs sources were identified:temperature dependent source(28.1%),vehicular exhausts(19.9%),petrochemical industries(7.2%),solvent&gasoline usage(32.3%)and manufacturing industries(12.6%).The increase of temperature and radiation would enhance the evaporation related VOC emissions,resulting in the increase of VOC concentration and the change of RO_(x)circulation.Our results highlight determination of the optimal control strategies for O_(3)pollution in a typical YRD industrial city.展开更多
Aerosol liquid water content(ALWC)plays an important role in secondary aerosol formation.In this study,a whole year field campaign was conducted at Shanxi in north Zhejiang Province during 2021.ALWC estimated by ISORR...Aerosol liquid water content(ALWC)plays an important role in secondary aerosol formation.In this study,a whole year field campaign was conducted at Shanxi in north Zhejiang Province during 2021.ALWC estimated by ISORROPIA-Ⅱ was then investigated to explore its characteristics and relationship with secondary aerosols.ALWC exhibited a highest value in spring(66.38μg/m^(3)),followed by winter(45.08μg/m^(3)),summer(41.64μg/m^(3)),and autumn(35.01μg/m^(3)),respectively.It was supposed that the secondary inorganic aerosols(SIA)were facilitated under higher ALWC conditions(RH>80%),while the secondary organic species tended to form under lower ALWC levels.Higher RH(>80%)promoted the NO_(3)^(-)formation via gas-particle partitioning,while SO_(4)^(2-)was generated at a relative lower RH(>50%).The ALWC was more sensitive to NO_(3)^(-)(R=0.94)than SO_(4)^(2-)(R=0.90).Thus,the self-amplifying processes between the ALWC and SIA enhanced the particle mass growth.The sensitivity of ALWC and OX(NO_(2)+O_(3))to secondary organic carbon(SOC)varied in different seasons at Shanxi,more sensitive to aqueous-phase reactions(daytime R=0.84;nighttime R=0.54)than photochemical oxidation(daytime R=0.23;nighttime R=0.41)in wintertime with a high level of OX(daytime:130-140μg/m^(3);nighttime:100-140μg/m^(3)).The self-amplifying process of ALWC and SIA and the aqueous-phase formation of SOC will enhance aerosol formation,contributing to air pollution and reduction of visibility.展开更多
The naked dinoflagellate Takayama acrotrocha was identified as responsible for a bloom in Shenzhen Bay,Guangdong,China,in early spring 2021.The identification was confirmed by light,scanning,and transmission electron ...The naked dinoflagellate Takayama acrotrocha was identified as responsible for a bloom in Shenzhen Bay,Guangdong,China,in early spring 2021.The identification was confirmed by light,scanning,and transmission electron microscopy and molecular data based on the LSU ribosomal DNA(rDNA)and ITS rDNA sequences.This is the first record of T.acrotrocha bloom in the South China Sea.The sulcus of T.acrotrocha was wide and extended onto the epicone as a short intrusion in general,sometime the intrusion was not apparent and some were finger-like.The apical groove was deeply sigmoid.The nucleus was large,ovoid to cup-shaped and occupied most of the epicone.A large,rounded pyrenoid surrounded by a starch sheath was located at the left side to the centre of the hypocone.Under epifluorescence illumination,a row of large vesicular knobs was observed on the upper border of the cingulum.The intraspecific morphological variabilities in the clonal cultures of T.acrotrocha were investigated carefully.Cells that share the same diagnostic characters used for the description of Takayama xiamenensis such as the finger-like sulcus,a large nucleus located in the epicone and the similar pyrenoid type were observed.The LSU rDNA sequences of T.acrotrocha and T.xiamenensis only differed in 3 base pairs(bp)for a sequence length of 673 bp(with a similarity of 99.55%).For these reasons,we propose T.xiamenensis as a junior synonym of T.acrotrocha.展开更多
Designing efficient and sustainable catalyst for peroxymonosulfate(PMS)activation and refractory 2,4,6-trichlorophenol(2,4,6-TCP)removal is an imminent task.This study synthesized a novelγ-MnO_(2)/NF catalyst,which h...Designing efficient and sustainable catalyst for peroxymonosulfate(PMS)activation and refractory 2,4,6-trichlorophenol(2,4,6-TCP)removal is an imminent task.This study synthesized a novelγ-MnO_(2)/NF catalyst,which has advantages in saving manganese dioxide demand and reducing manganese leaching.Theγ-MnO_(2)/NF+PMS oxidation system achieved a 0.219 min^(−1)2,4,6-TCP apparent rate constant at 20℃,and removed>90%of 2,4,6-TCP at the 5th cycle.Both free radical identification and DFT calculations revealed that•OH and SO_(4)^(•−),rather than 1O_(2),were the dominant reactive species duringγ-MnO_(2)/NF+PMS oxidation.The results indicated that the inner-sphere complexation betweenγ-MnO_(2)/NF and PMS facilitated the formation of•OH and SO_(4)^(•−).To fill the research gap in the molecular-level dissimilarities between•OH and SO_(4)^(•−)in 2,4,6-TCP degradation mechanism,experimental testing and quantum chemical analysis methods were used.The DFT calculation found that the HAA reaction at H13 site and RAF reaction at C1 site were more favorable for both•OH and SO_(4)^(•−).For most reaction sites,SO_(4)^(•−)demonstrates greater energy barriers and substrate selectivity than•OH,attributed to steric constraints.The•OH acted as the predominant oxidative agents responsible for 2,4,6-TCP decomposition.Combining DFT calculation and intermediate identification,potential degradation routes of 2,4,6-TCP were proposed.The ecotoxicity assays verified a substantial reduction in acute toxicity of the treated 2,4,6-TCP solution.This study opens up new avenues for activating PMS withγ-MnO_(2)/NF,and helps to select preferred radical oxidation processes for optimal 2,4,6-TCP removal in practical engineering.展开更多
Halogens are elements in soil and water that occur as organic and inorganic species.Studies have shown that inorganic halogens are closely related to animal and plant life.Matrix-assisted laser desorption/ionization m...Halogens are elements in soil and water that occur as organic and inorganic species.Studies have shown that inorganic halogens are closely related to animal and plant life.Matrix-assisted laser desorption/ionization mass spectrometry(MALDI-MS)can achieve high-throughput and rapid analysis,which is also an essential characteristic in some environmental studies.However,there is currently no report on MALDI-MS analysis for water-soluble inorganic halogen compounds.In this study,we aimed to develop a reliable and reproductive method to detect inorganic halogens in soil and water by MALDI-MS.Based on sinapic acid(SA)and silver trifluoromethanesulfonate(SA/AgOTf)as the matrix in negative-ion mode,MALDI-MS showed excellent MS signals related to halogens.Under the optimum conditions,the method achieved satisfactory linearity(R^(2)>0.99)and repeatability(RSD<18%).The LODs for Cl^(−),Br^(−)and I^(−)were 0.76,0.11 and 0.10μg/mL,respectively.The concentration of inorganic halogens from 24 samples was successfully determined by MALDI-MS.In summary,an innovative method was developed for the analysis of inorganic halogens by MALDI-MS using a novel SA/AgOTf matrix,extending the application of MALDI-MS in inorganic compounds.展开更多
A Zn‐based coating with durable hydrophobicity and good corrosion resistance was formed on a mild steel substrate,which involves electroplating Zn from a non‐aqueous electrolyte,followed by passivation in an oleic a...A Zn‐based coating with durable hydrophobicity and good corrosion resistance was formed on a mild steel substrate,which involves electroplating Zn from a non‐aqueous electrolyte,followed by passivation in an oleic acid(OA)solution.The electrodeposited Zn coatings were porous,which facilitated the formation of a chemical conversion layer of Zn oleate(ZO)during OA passivation.The Zn coating after passivation had a twolayer structure,which included an outer layer of ZO with a thickness of~26μm and an inner layer of Zn with a thickness of~6μm.The outer layer ZO is a type of metal soap with a smooth surface and durable hydrophobicity,such that water droplets can easily slip off its surface.Corrosion testing and electrochemical measurements in 3.5 wt.%NaCl aqueous solution indicate that the Zn coating after OA passivation exhibits outstanding anti‐corrosion properties compared with those exhibited by pure Zn coating.The corrosion products and mechanism of the two‐layer coating were explored.This study shows that smooth metal oleate coatings can provide hydrophobicity and corrosion resistance simultaneously to mild steel substrates.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42005086,91844301,and 41805100)the National Key Research and Development Programof China(No.2022YFC3703500)+2 种基金China Postdoctoral Science Foundation(No.2023M733028)the Key Research and Development Program of Zhejiang Province(Nos.2021C03165 and 2022C03084)the Ecological and Environmental Scientific Research and Achievement Promotion Project of Zhejiang Province(No.2020HT0048).
文摘Assessing the impact of anthropogenic volatile organic compounds(VOCs)on ozone(O_(3))formation is vital for themanagement of emission reduction and pollution control.Continuousmeasurement of O_(3)and the major precursorswas conducted in a typical light industrial city in the YRD region from 1 May to 25 July in 2021.Alkanes were the most abundant VOC group,contributing to 55.0%of TVOCs concentration(56.43±21.10 ppb).OVOCs,aromatics,halides,alkenes,and alkynes contributed 18.7%,9.6%,9.3%,5.2%and 1.9%,respectively.The observational site shifted from a typical VOC control regime to a mixed regime from May to July,which can be explained by the significant increase of RO_(x)production,resulting in the transition of environment from NOx saturation to radical saturation with respect to O_(3)production.The optimal O_(3)control strategy should be dynamically changed depending on the transition of control regime.Under NOx saturation condition,minimizing the proportion of NOx in reduction could lead to better achievement of O_(3)alleviation.Under mixed control regime,the cut percentage gets the top priority for the effectiveness of O_(3)control.Five VOCs sources were identified:temperature dependent source(28.1%),vehicular exhausts(19.9%),petrochemical industries(7.2%),solvent&gasoline usage(32.3%)and manufacturing industries(12.6%).The increase of temperature and radiation would enhance the evaporation related VOC emissions,resulting in the increase of VOC concentration and the change of RO_(x)circulation.Our results highlight determination of the optimal control strategies for O_(3)pollution in a typical YRD industrial city.
基金supported by the National Natural Science Foundation of China(Nos.91844301 and 42005087)the support from State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex,Shanghai Academy of Environment Sciences(No.CX2020080581)。
文摘Aerosol liquid water content(ALWC)plays an important role in secondary aerosol formation.In this study,a whole year field campaign was conducted at Shanxi in north Zhejiang Province during 2021.ALWC estimated by ISORROPIA-Ⅱ was then investigated to explore its characteristics and relationship with secondary aerosols.ALWC exhibited a highest value in spring(66.38μg/m^(3)),followed by winter(45.08μg/m^(3)),summer(41.64μg/m^(3)),and autumn(35.01μg/m^(3)),respectively.It was supposed that the secondary inorganic aerosols(SIA)were facilitated under higher ALWC conditions(RH>80%),while the secondary organic species tended to form under lower ALWC levels.Higher RH(>80%)promoted the NO_(3)^(-)formation via gas-particle partitioning,while SO_(4)^(2-)was generated at a relative lower RH(>50%).The ALWC was more sensitive to NO_(3)^(-)(R=0.94)than SO_(4)^(2-)(R=0.90).Thus,the self-amplifying processes between the ALWC and SIA enhanced the particle mass growth.The sensitivity of ALWC and OX(NO_(2)+O_(3))to secondary organic carbon(SOC)varied in different seasons at Shanxi,more sensitive to aqueous-phase reactions(daytime R=0.84;nighttime R=0.54)than photochemical oxidation(daytime R=0.23;nighttime R=0.41)in wintertime with a high level of OX(daytime:130-140μg/m^(3);nighttime:100-140μg/m^(3)).The self-amplifying process of ALWC and SIA and the aqueous-phase formation of SOC will enhance aerosol formation,contributing to air pollution and reduction of visibility.
基金Supported by the National Natural Science Foundation of China(Nos.41906112,42076144,42176201)the Science&Technology Basic Resources Investigation Program of China(No.2018FY100200)the Analysis Program on Key factors for Red Tide Forecast in Shenzhen。
文摘The naked dinoflagellate Takayama acrotrocha was identified as responsible for a bloom in Shenzhen Bay,Guangdong,China,in early spring 2021.The identification was confirmed by light,scanning,and transmission electron microscopy and molecular data based on the LSU ribosomal DNA(rDNA)and ITS rDNA sequences.This is the first record of T.acrotrocha bloom in the South China Sea.The sulcus of T.acrotrocha was wide and extended onto the epicone as a short intrusion in general,sometime the intrusion was not apparent and some were finger-like.The apical groove was deeply sigmoid.The nucleus was large,ovoid to cup-shaped and occupied most of the epicone.A large,rounded pyrenoid surrounded by a starch sheath was located at the left side to the centre of the hypocone.Under epifluorescence illumination,a row of large vesicular knobs was observed on the upper border of the cingulum.The intraspecific morphological variabilities in the clonal cultures of T.acrotrocha were investigated carefully.Cells that share the same diagnostic characters used for the description of Takayama xiamenensis such as the finger-like sulcus,a large nucleus located in the epicone and the similar pyrenoid type were observed.The LSU rDNA sequences of T.acrotrocha and T.xiamenensis only differed in 3 base pairs(bp)for a sequence length of 673 bp(with a similarity of 99.55%).For these reasons,we propose T.xiamenensis as a junior synonym of T.acrotrocha.
基金supported by“Pioneer and Leading Goose+X”S&T Program of Zhejiang,China(No.2025C02230)the National Natural Science Foundation of China(Nos.52400110 and 52070111).
文摘Designing efficient and sustainable catalyst for peroxymonosulfate(PMS)activation and refractory 2,4,6-trichlorophenol(2,4,6-TCP)removal is an imminent task.This study synthesized a novelγ-MnO_(2)/NF catalyst,which has advantages in saving manganese dioxide demand and reducing manganese leaching.Theγ-MnO_(2)/NF+PMS oxidation system achieved a 0.219 min^(−1)2,4,6-TCP apparent rate constant at 20℃,and removed>90%of 2,4,6-TCP at the 5th cycle.Both free radical identification and DFT calculations revealed that•OH and SO_(4)^(•−),rather than 1O_(2),were the dominant reactive species duringγ-MnO_(2)/NF+PMS oxidation.The results indicated that the inner-sphere complexation betweenγ-MnO_(2)/NF and PMS facilitated the formation of•OH and SO_(4)^(•−).To fill the research gap in the molecular-level dissimilarities between•OH and SO_(4)^(•−)in 2,4,6-TCP degradation mechanism,experimental testing and quantum chemical analysis methods were used.The DFT calculation found that the HAA reaction at H13 site and RAF reaction at C1 site were more favorable for both•OH and SO_(4)^(•−).For most reaction sites,SO_(4)^(•−)demonstrates greater energy barriers and substrate selectivity than•OH,attributed to steric constraints.The•OH acted as the predominant oxidative agents responsible for 2,4,6-TCP decomposition.Combining DFT calculation and intermediate identification,potential degradation routes of 2,4,6-TCP were proposed.The ecotoxicity assays verified a substantial reduction in acute toxicity of the treated 2,4,6-TCP solution.This study opens up new avenues for activating PMS withγ-MnO_(2)/NF,and helps to select preferred radical oxidation processes for optimal 2,4,6-TCP removal in practical engineering.
基金This study was jointly supported by the National Natural Science Foundation of China(21906137)the Science and Technology Program of Zhejiang Province(LGC21B050008).
文摘Halogens are elements in soil and water that occur as organic and inorganic species.Studies have shown that inorganic halogens are closely related to animal and plant life.Matrix-assisted laser desorption/ionization mass spectrometry(MALDI-MS)can achieve high-throughput and rapid analysis,which is also an essential characteristic in some environmental studies.However,there is currently no report on MALDI-MS analysis for water-soluble inorganic halogen compounds.In this study,we aimed to develop a reliable and reproductive method to detect inorganic halogens in soil and water by MALDI-MS.Based on sinapic acid(SA)and silver trifluoromethanesulfonate(SA/AgOTf)as the matrix in negative-ion mode,MALDI-MS showed excellent MS signals related to halogens.Under the optimum conditions,the method achieved satisfactory linearity(R^(2)>0.99)and repeatability(RSD<18%).The LODs for Cl^(−),Br^(−)and I^(−)were 0.76,0.11 and 0.10μg/mL,respectively.The concentration of inorganic halogens from 24 samples was successfully determined by MALDI-MS.In summary,an innovative method was developed for the analysis of inorganic halogens by MALDI-MS using a novel SA/AgOTf matrix,extending the application of MALDI-MS in inorganic compounds.
基金Zhejiang University K.P.Chao's High Technology Development Foundation。
文摘A Zn‐based coating with durable hydrophobicity and good corrosion resistance was formed on a mild steel substrate,which involves electroplating Zn from a non‐aqueous electrolyte,followed by passivation in an oleic acid(OA)solution.The electrodeposited Zn coatings were porous,which facilitated the formation of a chemical conversion layer of Zn oleate(ZO)during OA passivation.The Zn coating after passivation had a twolayer structure,which included an outer layer of ZO with a thickness of~26μm and an inner layer of Zn with a thickness of~6μm.The outer layer ZO is a type of metal soap with a smooth surface and durable hydrophobicity,such that water droplets can easily slip off its surface.Corrosion testing and electrochemical measurements in 3.5 wt.%NaCl aqueous solution indicate that the Zn coating after OA passivation exhibits outstanding anti‐corrosion properties compared with those exhibited by pure Zn coating.The corrosion products and mechanism of the two‐layer coating were explored.This study shows that smooth metal oleate coatings can provide hydrophobicity and corrosion resistance simultaneously to mild steel substrates.
