Nanostructured tin dioxide (SnO2) powders were prepared by a sol-gel dialytic process and and the doping of CuO on it was completed by a deposition-precipitation method.The thick film sensors were fabricated from th...Nanostructured tin dioxide (SnO2) powders were prepared by a sol-gel dialytic process and and the doping of CuO on it was completed by a deposition-precipitation method.The thick film sensors were fabricated from the CuO/SnO2 polycrystalline powders.Sensing behavior of the sensor was investigated with various gases including CO,H2,NH3,hexane,acetone,ethanol,methanol and H2S in air.The as-synthesized gas sensor had much better response to H2S than to other gases.At the same time,the CuO/SnO2 sensor had enough sensitivity,together with fast response and recovery,to distinguish H2S from those gases at 160 and 210 ℃.Therefore,it might have promising applications in the future.展开更多
Soil contamination by polycyclic aromatic hydrocarbons(PAHs)has raised great environmental concerns.However,the information on national wide distribution of PAHs in soil as well as their effect on soil bacterial commu...Soil contamination by polycyclic aromatic hydrocarbons(PAHs)has raised great environmental concerns.However,the information on national wide distribution of PAHs in soil as well as their effect on soil bacterial community are limited.In this study,16 PAHs weremeasured in 94 soil samples collected across China.The total concentration of 16 PAHs(PAHs)in soil ranged from 74.0 to 17,657 ng/g(dry weight basis),with a median value of 200 ng/g.Pyrene was themajor soil PAH,with amedian concentration of 71.3 ng/g.Soil samples from Northeast China had a higher median concentration ofPAHs(1,961 ng/g)than those from other regions.Petroleum emission and wood/grass/coal combustion were potential sources for soil PAHs based on diagnostic ratios and positive matrix factors analysis.A nonnegligible ecological risk(hazard quotients>1)was found in over 20%of soil samples analyzed and the highestmedian total HQs value(8.53)was found in soils from Northeast China.The effect of PAHs on bacterial abundance,α-diversity,andβ-diversity was limited in the soils surveyed.Nevertheless,the relative abundance of some members in genera Gaiella,Nocardioides,and Clostridium was significantly correlated with the concentrations of some PAHs.Especially,the bacterium Gaiella Occulta showed potential in indicating soil contamination by PAH,which is worth further exploration.展开更多
Arsenic(As)contamination in soil and water poses a serious threat to the ecosystem health and human beings,and is of widespread concern.The main As species found in soil and water are arsenite As(Ⅲ)and arsenate As(V)...Arsenic(As)contamination in soil and water poses a serious threat to the ecosystem health and human beings,and is of widespread concern.The main As species found in soil and water are arsenite As(Ⅲ)and arsenate As(V).Because As(Ⅲ)is more toxic and often more mobile than As(Ⅴ),many remediation strategies aim to oxidize As(Ⅲ)to As(Ⅴ).In the environment,the reduction of As(Ⅴ)under anaerobic conditions is mainly mediated by microorganisms,but the oxidation of As(Ⅲ)under aerobic conditions can be mediated primarily by chemical processes.This article first reviews the existing knowledge on chemical oxidation of As(Ⅲ)in the environment,with an emphasis on the roles of iron(Fe)and manganese(Mn)oxides.The application of Fe and Mn oxides for the remediation of As-contaminated soil and water is then summarized.The oxidation of As(Ⅲ)by oxygen is very slow in the absence of catalysts.Many Mn oxides,on the other hand,can efficiently oxidize As(Ⅲ).Although the oxidation of As(Ⅲ)by Fe(Ⅲ)is also slow,this process can be accelerated by light or Fe(Ⅱ).Iron and Mn oxides are widely used for the remediation of As-contaminated soil and water,with Fe oxides generally acting as absorbents while Mn oxides as oxidants.To better understand and regulate As transformation and transport in the environment,further study is needed on the mechanisms and influencing factors of As(Ⅲ)oxidation by Fe and Mn oxides,and the development of innovative methods and materials based on Fe and Mn oxides are desired.展开更多
Following exposure,neonicotinoid insecticides(NEOs)can be metabolized by both Phase Ⅰ and Phase Ⅱ reactions catalyzed by human cytochrome P450 enzymes.However,toxicities of parent NEOs and their metabolites are stil...Following exposure,neonicotinoid insecticides(NEOs)can be metabolized by both Phase Ⅰ and Phase Ⅱ reactions catalyzed by human cytochrome P450 enzymes.However,toxicities of parent NEOs and their metabolites are still unclear,and little is known about biotransformation rates and pathways of NEOs in humans.In this study,98 serum samples collected in China were analyzed for free,conjugated and total forms of six parent NEOs(i.e.,acetamiprid(ACE),imidacloprid(IMI),clothianidin(CLO),thiacloprid(THD),thiamethoxam(THM),and dinotefuran(DIN))and four metabolites(i.e.,N-desmethyl-acetamiprid(N-dm-ACE),1-methyl-3-(tetrahydro-3-furylmethyl)(DIN-U),5-hydroxy-imidacloprid(5-OH-IMI),olefin-imidacloprid(Of-IMI)).NEOs and their metabolites were detected in all serum samples,and the total median concentrations of free,conjugated,and total forms of 10 NEOs were 2.04,2.01,and 5.12 ng/mL,respectively.Conjugated forms of NEOs accounted for only half(53%)of the total forms of NEOs.Based on the profiles of Phase Ⅰ and Phase Ⅱ metabolites of NEOs in serum,it was found that age is a determinant in Phase Ⅰmetabolism of DIN and Phase Ⅱ metabolism of IMI.The Phase Ⅱmetabolites of NEOs are associated with oxidative DNA damage,and the conjugated forms of IMI,DIN,and 5-OH-IMI in serum were significantly positively correlated with oxidative stress.Overall,the amount of NEOs present in conjugated forms in human serum was determined to document the existence of a considerable proportion of free forms of these insecticides.展开更多
Cadmium(Cd) contamination in paddy soil has caused public concern. The uptake of Cd by rice plants depends on soil Cd mobility, which is in turn substantially influenced by organic matter(OM). In this review, we first...Cadmium(Cd) contamination in paddy soil has caused public concern. The uptake of Cd by rice plants depends on soil Cd mobility, which is in turn substantially influenced by organic matter(OM). In this review, we first summarize the fate of Cd in soil and the role of OM. We then focus on the effects of OM on Cd mobility in paddy soil and the factors influencing the remedial effectiveness of OM amendments. We further discuss the performance of straw incorporation in the remediation of Cd-contaminated paddy soils reported in laboratory and field studies. Considering the huge production of organic materials(such as straw) in agriculture, the use of natural OM for soil remediation has obvious appeal due to the environmental benefits and low cost. Although there have been successful application cases, the properties of OM amendments and soil can significantly affect the remedial performance of the OM amendments. Importantly, straw incorporation alone does not often decrease the mobility of Cd in soil or the Cd content in rice grains. Careful evaluation is required when considering natural OM amendments, and the factors and mechanisms that influence their remedial effectiveness need further investigation in paddy soil with realistic Cd concentrations.展开更多
A microcosm system that included river sediment,water and different zeolite capping materials(natural zeolite,surfactant-modified zeolite(SMZ),or aluminum modified zeolite(AMZ))was designed to study the effect of capp...A microcosm system that included river sediment,water and different zeolite capping materials(natural zeolite,surfactant-modified zeolite(SMZ),or aluminum modified zeolite(AMZ))was designed to study the effect of capping on the release of phosphorus and three organic pollutants(phenol,pyridine,and pyrene)from the sediment to the overlying water over the course of three month.For the same amount of the three capping materials,the efficiency of phosphorus inactivation was in the order of SMZ>AMZ>natural zeolite.The inactivation of phosphorus was mainly caused by the covering effect,co-precipitation and adsorption by the capping materials.The different zeolites gave different results for the release of phenol,pyridine,and pyrene from the sediment.When natural zeolite was used as the capping material,there was no effect on the release of pyrene and pyridine,whereas capping the sediment with SMZ or AMZ inhibited the release of pyrene and pyridine but to different extents.However,for controlling the release of phenol from the sediment,aluminum modified zeolite was the most efficient material,whereas no effects were observed when natural zeolite or SMZ were used.The different capabilities of the zeolite materials for controlling the release of different organic pollutants are related to the differences in the electrical properties of these pollutants.展开更多
The impacts of soil organic matter (SOM), aging and sterilization on the production of lignin peroxidase (LIP) and manganese peroxidase (MnP) by Phanerochaete chrysosporium during the biodegradation of pyrene in...The impacts of soil organic matter (SOM), aging and sterilization on the production of lignin peroxidase (LIP) and manganese peroxidase (MnP) by Phanerochaete chrysosporium during the biodegradation of pyrene in soils were investigated. The biodegradation of pyrene by P. chrysosporium decreased with increasing SOM content, whereas the maximum activities of LiP and MnP increased, which indicates that SOM outweighed pyrene in controlling enzyme production. Sterilization enhanced the degradation of pyrene due to the elimination of competition from indigenous microbes, whereas aging led to a reduction in the degradation of pyrene primarily through changes in its sorbed forms. Both sterilization and aging could reduce SOM content and alter its structure, which also influenced the bioavailability of pyrene and the enzyme activity. The sterilization and aging processes caused changes in the degradation of pyrene, and the enzyme activities were greater in soils with high SOM contents. MnP was related to the degradation of pyrene to a greater extent, whereas LiP was more related to the decomposition of SOM.展开更多
The purpose of this study is to estimate the removal efficiency of As and Cr(VI)by one kind of industrial waste–iron chips,as well as to estimate the effects of typical inorganic anions(sulfate,phosphate,and nitrate)...The purpose of this study is to estimate the removal efficiency of As and Cr(VI)by one kind of industrial waste–iron chips,as well as to estimate the effects of typical inorganic anions(sulfate,phosphate,and nitrate),and typical organic anions(citrate,oxalate,and humate)on As or Cr(VI)removal.The results showed that 98%of As(V)and 92%of As(III)could be removed from aqueous phase by the iron chips within 60 min.Compared with As species,Cr(VI)was removed much more rapidly and efficiently with 97%of Cr(VI)being removed within 25 min.The removal efficiency for arsenic was in the order:As(III)(sulfate),As(III)(nitrate)or As(III),As(III)(humate),As(III)(oxalate),As(III)(citrate),As(III)(phosphate),and for chromate was in the order:Cr(VI)(sulfate),Cr(VI)(phosphate)or Cr(VI)(nitrate)or Cr(VI)(oxalate),Cr(VI),Cr(VI)(citrate),Cr(VI)(humate).In all the treatments,pH level increased with time except for As(III),the removal of which was either without anions or in the presence of humate or nitrate.展开更多
Application of biochar technology in the remediation of organic contaminated soils has drawn growing interest in recent years.In this study,sorption and degradation of two typical neonicotinoid insecticides,imidaclopr...Application of biochar technology in the remediation of organic contaminated soils has drawn growing interest in recent years.In this study,sorption and degradation of two typical neonicotinoid insecticides,imidacloprid(IMI)and clothianidin(CLO)in Chinese typical paddy soil and red soil amended with six kinds of biochars were investigated.The results showed that surface area(SA),pH,total organic carbon and dissolved organic carbon(DOC)of the two soils all increased after biochar amendment,while H/C decreased.With biochar pyrolyzing temperature(PT)increasing from 300℃ to 700℃,the sorption of the two insecticides on biochar-soil mixtures increased by more than 4.3-fold,due to the increasing SA and decreasing H/C.The acidic pH of the two tested soils also favored the enhanced sorption of the insecticides by removing the ash on biochar.The amendment of low-PT(300℃)biochar promoted the biodegradation of IMI and CLO by 11.3-41.9%via providing more DOC and available N for microorganisms,while inhibiting the chemical degradation.Oppositely,the high-PT(500-700℃)biochars inhibited the biodegradation of the insecticides by decreasing their bioavailability and promoted the chemical degradation by providing mineral active groups,and generating·OH and other free radicals.In addition,soil type also affected the effects of biochar remediation.The highest 60-day degradation extent was achieved for CLO(90.5%)and IMI(81.4%)in paddy soil by adding biochar derived from pig manure at 700℃ PT.In summary,the effect of biochar on the fate of organic contaminants in soil is a comprehensive result involving several processes and a systematic study considering the type and property of biochar and soil is needed to optimize biochar technology.展开更多
文摘Nanostructured tin dioxide (SnO2) powders were prepared by a sol-gel dialytic process and and the doping of CuO on it was completed by a deposition-precipitation method.The thick film sensors were fabricated from the CuO/SnO2 polycrystalline powders.Sensing behavior of the sensor was investigated with various gases including CO,H2,NH3,hexane,acetone,ethanol,methanol and H2S in air.The as-synthesized gas sensor had much better response to H2S than to other gases.At the same time,the CuO/SnO2 sensor had enough sensitivity,together with fast response and recovery,to distinguish H2S from those gases at 160 and 210 ℃.Therefore,it might have promising applications in the future.
基金This work was funded by the National Key Research and Development Program of China(No.2020YFC1807000)the National Natural Science Foundation of China(Nos.42007328,41977273 and U21A20291)+1 种基金the Major Scientific and Technological Innovation Project of Shandong Province(No.2021CXGC011206)the 111 Program,Ministry of Education,China(No.T2017002).
文摘Soil contamination by polycyclic aromatic hydrocarbons(PAHs)has raised great environmental concerns.However,the information on national wide distribution of PAHs in soil as well as their effect on soil bacterial community are limited.In this study,16 PAHs weremeasured in 94 soil samples collected across China.The total concentration of 16 PAHs(PAHs)in soil ranged from 74.0 to 17,657 ng/g(dry weight basis),with a median value of 200 ng/g.Pyrene was themajor soil PAH,with amedian concentration of 71.3 ng/g.Soil samples from Northeast China had a higher median concentration ofPAHs(1,961 ng/g)than those from other regions.Petroleum emission and wood/grass/coal combustion were potential sources for soil PAHs based on diagnostic ratios and positive matrix factors analysis.A nonnegligible ecological risk(hazard quotients>1)was found in over 20%of soil samples analyzed and the highestmedian total HQs value(8.53)was found in soils from Northeast China.The effect of PAHs on bacterial abundance,α-diversity,andβ-diversity was limited in the soils surveyed.Nevertheless,the relative abundance of some members in genera Gaiella,Nocardioides,and Clostridium was significantly correlated with the concentrations of some PAHs.Especially,the bacterium Gaiella Occulta showed potential in indicating soil contamination by PAH,which is worth further exploration.
基金supported by the National Natural Science Foundation of China(Nos.41977273 and U21A20291)the National Key Research and Development Program of China(No.2018YFC1800702)+1 种基金the Major Research Plan of the Shandong Science Foundation,China(No.ZR2020ZD19)funding from the Special Fund for Basic Scientific Research Business of Central Public Research Institutes,China(No.K-JBYWF-2019-T04).
文摘Arsenic(As)contamination in soil and water poses a serious threat to the ecosystem health and human beings,and is of widespread concern.The main As species found in soil and water are arsenite As(Ⅲ)and arsenate As(V).Because As(Ⅲ)is more toxic and often more mobile than As(Ⅴ),many remediation strategies aim to oxidize As(Ⅲ)to As(Ⅴ).In the environment,the reduction of As(Ⅴ)under anaerobic conditions is mainly mediated by microorganisms,but the oxidation of As(Ⅲ)under aerobic conditions can be mediated primarily by chemical processes.This article first reviews the existing knowledge on chemical oxidation of As(Ⅲ)in the environment,with an emphasis on the roles of iron(Fe)and manganese(Mn)oxides.The application of Fe and Mn oxides for the remediation of As-contaminated soil and water is then summarized.The oxidation of As(Ⅲ)by oxygen is very slow in the absence of catalysts.Many Mn oxides,on the other hand,can efficiently oxidize As(Ⅲ).Although the oxidation of As(Ⅲ)by Fe(Ⅲ)is also slow,this process can be accelerated by light or Fe(Ⅱ).Iron and Mn oxides are widely used for the remediation of As-contaminated soil and water,with Fe oxides generally acting as absorbents while Mn oxides as oxidants.To better understand and regulate As transformation and transport in the environment,further study is needed on the mechanisms and influencing factors of As(Ⅲ)oxidation by Fe and Mn oxides,and the development of innovative methods and materials based on Fe and Mn oxides are desired.
基金The Natural Science Foundation of China(Nos.22022612,22036004,and 21677184)Natural Science Foundation of Guangdong Province,China(Nos.2020A0104006 and 2021A1515010243)are acknowledged for their partial research support.We gratefully acknowledge the donors who contributed blood samples to this study.
文摘Following exposure,neonicotinoid insecticides(NEOs)can be metabolized by both Phase Ⅰ and Phase Ⅱ reactions catalyzed by human cytochrome P450 enzymes.However,toxicities of parent NEOs and their metabolites are still unclear,and little is known about biotransformation rates and pathways of NEOs in humans.In this study,98 serum samples collected in China were analyzed for free,conjugated and total forms of six parent NEOs(i.e.,acetamiprid(ACE),imidacloprid(IMI),clothianidin(CLO),thiacloprid(THD),thiamethoxam(THM),and dinotefuran(DIN))and four metabolites(i.e.,N-desmethyl-acetamiprid(N-dm-ACE),1-methyl-3-(tetrahydro-3-furylmethyl)(DIN-U),5-hydroxy-imidacloprid(5-OH-IMI),olefin-imidacloprid(Of-IMI)).NEOs and their metabolites were detected in all serum samples,and the total median concentrations of free,conjugated,and total forms of 10 NEOs were 2.04,2.01,and 5.12 ng/mL,respectively.Conjugated forms of NEOs accounted for only half(53%)of the total forms of NEOs.Based on the profiles of Phase Ⅰ and Phase Ⅱ metabolites of NEOs in serum,it was found that age is a determinant in Phase Ⅰmetabolism of DIN and Phase Ⅱ metabolism of IMI.The Phase Ⅱmetabolites of NEOs are associated with oxidative DNA damage,and the conjugated forms of IMI,DIN,and 5-OH-IMI in serum were significantly positively correlated with oxidative stress.Overall,the amount of NEOs present in conjugated forms in human serum was determined to document the existence of a considerable proportion of free forms of these insecticides.
基金supported by the National Natural Science Foundation of China (No. 41977273 )the National Key Research and Development Program of China (No. 2018YFC1800702 )the Natural Science Foundation of Tianjin City (No. 19JCQNJC07700 )。
文摘Cadmium(Cd) contamination in paddy soil has caused public concern. The uptake of Cd by rice plants depends on soil Cd mobility, which is in turn substantially influenced by organic matter(OM). In this review, we first summarize the fate of Cd in soil and the role of OM. We then focus on the effects of OM on Cd mobility in paddy soil and the factors influencing the remedial effectiveness of OM amendments. We further discuss the performance of straw incorporation in the remediation of Cd-contaminated paddy soils reported in laboratory and field studies. Considering the huge production of organic materials(such as straw) in agriculture, the use of natural OM for soil remediation has obvious appeal due to the environmental benefits and low cost. Although there have been successful application cases, the properties of OM amendments and soil can significantly affect the remedial performance of the OM amendments. Importantly, straw incorporation alone does not often decrease the mobility of Cd in soil or the Cd content in rice grains. Careful evaluation is required when considering natural OM amendments, and the factors and mechanisms that influence their remedial effectiveness need further investigation in paddy soil with realistic Cd concentrations.
基金supported by the National Natural Science Foundation of China(Grant Nos.20677031,20737002).
文摘A microcosm system that included river sediment,water and different zeolite capping materials(natural zeolite,surfactant-modified zeolite(SMZ),or aluminum modified zeolite(AMZ))was designed to study the effect of capping on the release of phosphorus and three organic pollutants(phenol,pyridine,and pyrene)from the sediment to the overlying water over the course of three month.For the same amount of the three capping materials,the efficiency of phosphorus inactivation was in the order of SMZ>AMZ>natural zeolite.The inactivation of phosphorus was mainly caused by the covering effect,co-precipitation and adsorption by the capping materials.The different zeolites gave different results for the release of phenol,pyridine,and pyrene from the sediment.When natural zeolite was used as the capping material,there was no effect on the release of pyrene and pyridine,whereas capping the sediment with SMZ or AMZ inhibited the release of pyrene and pyridine but to different extents.However,for controlling the release of phenol from the sediment,aluminum modified zeolite was the most efficient material,whereas no effects were observed when natural zeolite or SMZ were used.The different capabilities of the zeolite materials for controlling the release of different organic pollutants are related to the differences in the electrical properties of these pollutants.
基金supported by the Tianjin Science and Technology Committee(No.10JCZDJC24200)the Ministry of Science and Technology of China(No.2014CB441104,2008AA06Z333)the Natural Science Foundation of China(No.20907024)
文摘The impacts of soil organic matter (SOM), aging and sterilization on the production of lignin peroxidase (LIP) and manganese peroxidase (MnP) by Phanerochaete chrysosporium during the biodegradation of pyrene in soils were investigated. The biodegradation of pyrene by P. chrysosporium decreased with increasing SOM content, whereas the maximum activities of LiP and MnP increased, which indicates that SOM outweighed pyrene in controlling enzyme production. Sterilization enhanced the degradation of pyrene due to the elimination of competition from indigenous microbes, whereas aging led to a reduction in the degradation of pyrene primarily through changes in its sorbed forms. Both sterilization and aging could reduce SOM content and alter its structure, which also influenced the bioavailability of pyrene and the enzyme activity. The sterilization and aging processes caused changes in the degradation of pyrene, and the enzyme activities were greater in soils with high SOM contents. MnP was related to the degradation of pyrene to a greater extent, whereas LiP was more related to the decomposition of SOM.
基金This paper was supported by Asian Institute at Nankai University,Tianjin,China.
文摘The purpose of this study is to estimate the removal efficiency of As and Cr(VI)by one kind of industrial waste–iron chips,as well as to estimate the effects of typical inorganic anions(sulfate,phosphate,and nitrate),and typical organic anions(citrate,oxalate,and humate)on As or Cr(VI)removal.The results showed that 98%of As(V)and 92%of As(III)could be removed from aqueous phase by the iron chips within 60 min.Compared with As species,Cr(VI)was removed much more rapidly and efficiently with 97%of Cr(VI)being removed within 25 min.The removal efficiency for arsenic was in the order:As(III)(sulfate),As(III)(nitrate)or As(III),As(III)(humate),As(III)(oxalate),As(III)(citrate),As(III)(phosphate),and for chromate was in the order:Cr(VI)(sulfate),Cr(VI)(phosphate)or Cr(VI)(nitrate)or Cr(VI)(oxalate),Cr(VI),Cr(VI)(citrate),Cr(VI)(humate).In all the treatments,pH level increased with time except for As(III),the removal of which was either without anions or in the presence of humate or nitrate.
基金supported by the National Key R&D Program of China(2018YFC1802001)the special fund of platform for innovation of Tianjin Science and Technology Commission(19PTZWHZ00040)+1 种基金Science and Technology Major Project of Tianjin(19ZXSZSN00010)and Postdoctoral Science Foundation of China(2019M651018)Ministry of Education of China(111 program,T2017002).
文摘Application of biochar technology in the remediation of organic contaminated soils has drawn growing interest in recent years.In this study,sorption and degradation of two typical neonicotinoid insecticides,imidacloprid(IMI)and clothianidin(CLO)in Chinese typical paddy soil and red soil amended with six kinds of biochars were investigated.The results showed that surface area(SA),pH,total organic carbon and dissolved organic carbon(DOC)of the two soils all increased after biochar amendment,while H/C decreased.With biochar pyrolyzing temperature(PT)increasing from 300℃ to 700℃,the sorption of the two insecticides on biochar-soil mixtures increased by more than 4.3-fold,due to the increasing SA and decreasing H/C.The acidic pH of the two tested soils also favored the enhanced sorption of the insecticides by removing the ash on biochar.The amendment of low-PT(300℃)biochar promoted the biodegradation of IMI and CLO by 11.3-41.9%via providing more DOC and available N for microorganisms,while inhibiting the chemical degradation.Oppositely,the high-PT(500-700℃)biochars inhibited the biodegradation of the insecticides by decreasing their bioavailability and promoted the chemical degradation by providing mineral active groups,and generating·OH and other free radicals.In addition,soil type also affected the effects of biochar remediation.The highest 60-day degradation extent was achieved for CLO(90.5%)and IMI(81.4%)in paddy soil by adding biochar derived from pig manure at 700℃ PT.In summary,the effect of biochar on the fate of organic contaminants in soil is a comprehensive result involving several processes and a systematic study considering the type and property of biochar and soil is needed to optimize biochar technology.