Graphdiyne(GDY)and its derivatives have been considered ideal supporting materials for nanoscale active particles because of their unique atomic and electronic structure.An efficient bi-metal Cu-Pd catalyst was added ...Graphdiyne(GDY)and its derivatives have been considered ideal supporting materials for nanoscale active particles because of their unique atomic and electronic structure.An efficient bi-metal Cu-Pd catalyst was added to produce the uniform deposition of Pd nano-clusters with an average size of~0.95 nm on hydrogen-substituted GDY(HGDY)nanosheets.With the assistance of NaBH4,the resulting Pd/H-GDY was very effective in the degradation of 4-nitrophenol(4-NP),whose conversion was sharply increased to 97.21%in 100 s with a rate constant per unit mass(k`)of 8.97×10^(5)min−1 g^(−1).Additionally,dyes such as methyl orange(MO)and Congo red(CR)were completely degraded within 180 and 90 s,respectively.The Pd/H-GDY maintained this activity after 5 reduction cycles.These results highlight the promising performance of Pd/H-GDY in catalyzing the degradation of various pollutants,which is attributed to the combined effect of the largeπ-conjugated structure of the H-GDY nanosheets and the evenly distributed Pd nanoclusters.展开更多
Buckypapers(BPs)consist of carbon nanotube(CNT)membranes with good mechanical,thermal and elec-trical properties.We report the modification of CNT buckypapers by the surface deposition of a thin layer of ti-tanium dio...Buckypapers(BPs)consist of carbon nanotube(CNT)membranes with good mechanical,thermal and elec-trical properties.We report the modification of CNT buckypapers by the surface deposition of a thin layer of ti-tanium dioxide and their subsequent photocatalytic use for the removal of three wastewater pollutants:diclofenac(DF),carbofuran(CB)and methylene blue(MB).The results show the following decreases(RE)in the initial concentrations of these pollutants,REDF=99.5%,REMB=96%and RECB=90%after 90 min of exposure to UV-Vis radiation using~0.6 mg of photocatalyst.Experiments also showed that the degradation rate of diclofenac(k=0.1028 min^(−1))is respectively 3.5 and 6 times faster than the values for CB(k=0.0298 min^(−1))and MB(k=0.0174 min^(−1)),probably due to the easier bond cleavage in DF.UV-Vis irradiated solutions of these pollutants were then analyzed by mass spectrometry to identify the species formed during photocatalysis and suggest possible degradation paths for MB,DF,and CB.Data showed that the degradation of DF involves the formation of a photocyclization product through loss of HCl molecule,clearly consuming less energy than that needed for the opening of the central aromatic ring in MB,or the loss of the N-methyl amide functional group for CB.展开更多
The features of organic pollutants degradation mainly characterized by bio-flocculation for step-A of adsorption-biodegredation（AB） process were studied. By investigating the relationship of extracellular polymeric ...The features of organic pollutants degradation mainly characterized by bio-flocculation for step-A of adsorption-biodegredation（AB） process were studied. By investigating the relationship of extracellular polymeric substances（EPS） with bioflocculation and introducing kinetic model of organic pollutant degradation into EPS, the kinetic model of organic pollutant degradation for step-A hioflocculation was deducted. And through the experiments, the kinetic constants were calculated as follows： k1 =0. 005 3; kc1 =1 710.7 and vmax1=10 min^-1.展开更多
By conducting experimental measurements and numerical simulations of air distribution and microorganism pollutant distribution in the auditorium and game area in a gymnasium,pollutant dispersion control and indoor air...By conducting experimental measurements and numerical simulations of air distribution and microorganism pollutant distribution in the auditorium and game area in a gymnasium,pollutant dispersion control and indoor air quality improvement methods were put forward. The results show that the fungi and bacteria concentration levels are less than the magnitude of 103 CFU (colony-forming units) which meets the requirements of indoor air quality standard. The numerical simulation results quantitatively agree with the experimental data while some differences between theoretical data and experimental data exist in air distributions. People number in gymnasium plays an important role in affecting indoor air quality and the environmental parameters attained the standard.展开更多
This essay briefly introduces the historical development of gas chromatography and mass spectrometry technology,it combines important results of GC and GC-MS in environmental monitoring,GC and GC-MS may analyse Polynu...This essay briefly introduces the historical development of gas chromatography and mass spectrometry technology,it combines important results of GC and GC-MS in environmental monitoring,GC and GC-MS may analyse Polynuclear aromatic hydrocarbons,Pesticide,PCBs,PDBEs and Multicomposit ion of organic pollutants,etc.It also elaborates the developing trend of the gas chromatography technology.展开更多
In order to explore the remediation effects of lignite and biochar on Zn-contaminated soil,this experiment studied the impacts of adding lignite and biochar on soil respiration,soil enzyme activity,and organic carbon ...In order to explore the remediation effects of lignite and biochar on Zn-contaminated soil,this experiment studied the impacts of adding lignite and biochar on soil respiration,soil enzyme activity,and organic carbon in Zn-contaminated soil through soil culture experiments,which provided a theoretical basis for the remediation and improvement as well as for the development and utilization of Zn-contaminated soil.The study was an L8(4×2^(2))orthogonal experimental design with eight treatments,in which there were four levels of Zn contamination concentration(Z0:0;Z1:125 mg•kg^(-1);Z2:250 mg•kg^(-1);Z3:500 mg•kg^(-1)),low-Zn(125-250 mg•kg^(-1))and high-Zn(500 mg•kg^(-1)),two levels of lignite(H0:0;H1:13.33 g•kg^(-1)),two levels of biochar(C0:0;C1:3.33 g•kg^(-1)),with four replicates per treatment.The results showed that lignite or biochar and their interaction had extremely significant effects on both respiration rate and accumulation in Zn-contaminated soil.Among the high Zn-contaminated treatments,the mixed application of lignite and biochar(Z3H1C1 treatment)had the fastest soil respiration rate and the highest soil respiration accumulation.Lignite,biochar and their interaction had significant or extremely significant effects on sucrase,catalase and polyphenol oxidase activities in Zn-contaminated soil.Among the high Zn-contaminated treatments(Z3),the addition of biochar alone had the most significant effects on the increase of soil sucrase and catalase enzyme activities,while the mixed application of lignite and biochar had the most significant effects on the increase of soil polyphenol oxidase activity.Lignite,biochar and their interaction had significant or extremely significant effects on the total organic carbon,active organic carbon and microbial carbon content of Zn-contaminated soils.Soil total organic carbon content in general peaked at day 80.Among the high Zn-contaminated treatments,the addition of biochar alone had the most significant effects on the total organic carbon content of the soil,while the mixed application of lignite and biochar had the most significant effect on the microbiomass carbon content.展开更多
The aerosols has been collected by sample of high-volume sampler in Beijing,and the concentrations of n-alkane in aerosol samples were determined via GC-MS.The n-alkane homolog was from C10 to C33.The total concentrat...The aerosols has been collected by sample of high-volume sampler in Beijing,and the concentrations of n-alkane in aerosol samples were determined via GC-MS.The n-alkane homolog was from C10 to C33.The total concentrations of n-alkanes in aerosol of Beijing varied from 176.22 to 5 410.2 ng/m3 in PM10 and from 77.89 to 3 138.9 ng/m3 in PM2.5,respectively,during the year and were higher in winter time than those in the other three season.The carbon numbers of main peaks of n-alkanes were 25,27,29 in spring,and 27,29,31 in summer,27,29 in autumn,25 in winter for PM10 samples,respectively.CPI in four seasons was close to 1.0,which indicated that n-alkanes were mainly from combustion of fossil fuel like petroleum,partially from advanced plants.展开更多
It′s very useful tools for an instant analysis of organic pollutants monitoring using the HAPSITE portable GC-MS.It discusses how to use HAPSITE portable GC-MS in emergency monitoring and treatment.
The application of photocatalytic technology in H_(2) production,CO_(2) reduction,H_(2)O_(2) production,and pollutant degradation provides a promising approach to the alleviation of energy shortage and environmental i...The application of photocatalytic technology in H_(2) production,CO_(2) reduction,H_(2)O_(2) production,and pollutant degradation provides a promising approach to the alleviation of energy shortage and environmental issues 1-3.However,hindered by the easy recombination of electron-hole pairs,single-component photocatalysts usually exhibit inferior performance.Constructing heterojunction photocatalysts is a valid method which can improve charge separation and attain high catalytic efficiencies4.展开更多
Oxygen fuels have broad application prospects and great potential for realizing efficient and clean combustion,and hence this study applies diesel/n-butanol blends to explore the influence of split-injection strategy ...Oxygen fuels have broad application prospects and great potential for realizing efficient and clean combustion,and hence this study applies diesel/n-butanol blends to explore the influence of split-injection strategy on combustion and emission characteristics.Simultaneously,changing the way of exhaust gas recirculation(EGR)gas introduction forms uneven in-cylinder components distribution,and utilizing EGR stratification optimizes the combustion process and allows better emission results.The results show that the split-injection strategy can reduce the NO_(x)emissions and keep smoke opacity low compared with the single injection,but the rise in accumulation mode particles is noticeable.NO_(x)emissions show an upward trend as the injection interval expands,while soot emissions are significantly reduced.The increase in pre-injection proportion causes the apparent low-temperature heat release,and the two-stage heat release can be observed during the process of main combustion heat release.More pre-injection mass makes NO_(x)gradually increase,but smoke opacity reaches the lowest point at 15%pre-injection proportion.EGR stratification can optimize the emission results under the split injection strategy,especially the considerable suppression of accumulation mode particulate emissions.Above all,fuel stratification coupled with EGR stratification is beneficial for further realizing the in-cylinder purification of pollutants.展开更多
The mechanism of health effects caused by organohalogen pollutants, e.g., toxins from electronic waste(e-waste), is poorly understood. We supposed that micro RNAs(mi RNAs), an important post-transcriptional regulator,...The mechanism of health effects caused by organohalogen pollutants, e.g., toxins from electronic waste(e-waste), is poorly understood. We supposed that micro RNAs(mi RNAs), an important post-transcriptional regulator, could play a role in this process. In this study, fasting peripheral blood samples were collected from residents living at an e-waste site in northern China and a nearby reference population. Concentrations of e-waste related organohalogen pollutants in plasma from the exposure group were higher than the corresponding measurement in the reference group. Correspondingly, sixty mi RNAs in plasma showed > 2-fold change between the two groups in microarray analysis. Among them, mi R-125a-5p was confirmed to be upregulated by q RT-PCR and its validated targets were enriched in responses to xenobiotics and cancer related pathways. Furthermore, significant positive correlations were found between levels of mi R-125a-5p in plasma and reactive oxygen species(ROS) in polymorphonuclear neutrophil leukocytes(P < 0.05). These evidences suggested oxidative stress might be an intermediate between e-waste related POPs exposure and alteration of plasma mi RNA.展开更多
Soil cadmium(Cd)contamination resulted from mining and smelting is a major environmental concern,and health risk associated with Cd exposure to multi-media through muti-pathway is increasing.Cd concentrations in soils...Soil cadmium(Cd)contamination resulted from mining and smelting is a major environmental concern,and health risk associated with Cd exposure to multi-media through muti-pathway is increasing.Cd concentrations in soils,vegetables and paddy rice were investigated,and potential non-carcinogenic and carcinogenic health risks exposure to Cd were estimated at six villages around the Dabaoshan Mine,South China.A total of 87 soil samples were found to exceed the China's maximum permission level(MPL)for Cd,while the highest value of 4.42 mg/kg was found near irrigation ditch associated with Hengshi River in Xinyi(XY)Village.Cd contents in vegetables and rice exceeded the maximum permissible concentration by more than five times in every village.Cadmium accumulation in plants is in the order of celery>lactuca sativa L>Chinese cabbage>Romaine lettuce>asparagus lettuce>mustard>cabbage mustard>cabbage.The mean hazard quotient(HQ)of all villages is in the range of [5.29,25.75],and the mean values of cancer risk for investigated areas are more than 10 times greater than the USEPA(2009)threshold limit value of 10-4.Moreover,human non-carcinogenic and carcinogenic risks are mainly attributable to paddy rice intake,followed by vegetables intake,soil ingestion,inhalation,and dermal contact.The results indicate that Cd has a huge potential risk on human health for the local residents.展开更多
Eleven plant species were collected from the vicinity of lead-battery plant in the city of Gaziantep,Turkey.Lead,cadmium and copper concentrations in the soil and leaves of plants were determined by atomic absorption ...Eleven plant species were collected from the vicinity of lead-battery plant in the city of Gaziantep,Turkey.Lead,cadmium and copper concentrations in the soil and leaves of plants were determined by atomic absorption spectrometry.Lead,Cd and Cu concentrations in the soil samples taken from battery area were found to be in the ranges of 304～602,0.4～0.44 and 31～37 mg·kg-1,respectively.Significantly increased lead concentration up to 2 750 mg·kg-1 was found in the leaves of Eleagnus angustifolia L.plant.The lead concentrations in the other plant leaves taken from 50 m around battery factory followed the order Ailanthus altissima>Morus sp.>Juglans regia L.>Ficus carica L.>Cydonia oblonga Miller>Prunus x domestica L.The plants,Populus nigra L.,Eleagnus angustifolia L.and Salix sp.were found useful for Cd,and the plant,Eleagnus angustifolia L.for Pb,to be considered as potential biomonitor.Especially,leaves of trees and plants taken from the distance of 50 m from battery plant have relatively higher Pb concentrations.Therefore,people who and animals which live in this area and benefit from these soil and plants have vital risks.展开更多
In order to control the dust pollution produced by air leg rock drill in the trolley area during the excavation of long-distance single ended tunnel,the full-scale physical model of working face was established by usi...In order to control the dust pollution produced by air leg rock drill in the trolley area during the excavation of long-distance single ended tunnel,the full-scale physical model of working face was established by using FLUENT software,and the numerical simulation analysis of tunnel drilling ventilation and dust removal parameters was carried out.The results show that it is difficult to control the dust pollution of the face by conventional ventilation,and the drilling dust is distributed in the range of 10 m from the face;after the introduction of the long pressure and short suction ventilation scheme,when the ratio of compressed air volume to exhaust air volume is 0.72,the height of the pressure fan is 2.5 m,the distance between the pressure fan and the palm face is 20 m,and the exhaust fan is 12 m away from the palm,the dust concentration control efficiency of the working face is increased by about 60%.Therefore,in the similar long-distance single head tunnel construction,it is appropriate to adopt the dust removal method of long-distance short suction and exhaust fan to ensure the working environment.展开更多
基金National Natural Science Foundation of China(52072336,51902285)Zhejiang Provincial Natural Science Foundation(LR23E020002)+1 种基金Fundamental Research Funds for the Central Universities(226-2023-00064,226-2024-00146)Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(2022SZ-FR001)。
文摘Graphdiyne(GDY)and its derivatives have been considered ideal supporting materials for nanoscale active particles because of their unique atomic and electronic structure.An efficient bi-metal Cu-Pd catalyst was added to produce the uniform deposition of Pd nano-clusters with an average size of~0.95 nm on hydrogen-substituted GDY(HGDY)nanosheets.With the assistance of NaBH4,the resulting Pd/H-GDY was very effective in the degradation of 4-nitrophenol(4-NP),whose conversion was sharply increased to 97.21%in 100 s with a rate constant per unit mass(k`)of 8.97×10^(5)min−1 g^(−1).Additionally,dyes such as methyl orange(MO)and Congo red(CR)were completely degraded within 180 and 90 s,respectively.The Pd/H-GDY maintained this activity after 5 reduction cycles.These results highlight the promising performance of Pd/H-GDY in catalyzing the degradation of various pollutants,which is attributed to the combined effect of the largeπ-conjugated structure of the H-GDY nanosheets and the evenly distributed Pd nanoclusters.
基金MIUR,Italian Ministry for University and Research(EX-60%/2024)。
文摘Buckypapers(BPs)consist of carbon nanotube(CNT)membranes with good mechanical,thermal and elec-trical properties.We report the modification of CNT buckypapers by the surface deposition of a thin layer of ti-tanium dioxide and their subsequent photocatalytic use for the removal of three wastewater pollutants:diclofenac(DF),carbofuran(CB)and methylene blue(MB).The results show the following decreases(RE)in the initial concentrations of these pollutants,REDF=99.5%,REMB=96%and RECB=90%after 90 min of exposure to UV-Vis radiation using~0.6 mg of photocatalyst.Experiments also showed that the degradation rate of diclofenac(k=0.1028 min^(−1))is respectively 3.5 and 6 times faster than the values for CB(k=0.0298 min^(−1))and MB(k=0.0174 min^(−1)),probably due to the easier bond cleavage in DF.UV-Vis irradiated solutions of these pollutants were then analyzed by mass spectrometry to identify the species formed during photocatalysis and suggest possible degradation paths for MB,DF,and CB.Data showed that the degradation of DF involves the formation of a photocyclization product through loss of HCl molecule,clearly consuming less energy than that needed for the opening of the central aromatic ring in MB,or the loss of the N-methyl amide functional group for CB.
基金project (2004B4604A01-01) supported by the Mega-projects of Science Research for the 10th Five-Year Plan
文摘The features of organic pollutants degradation mainly characterized by bio-flocculation for step-A of adsorption-biodegredation（AB） process were studied. By investigating the relationship of extracellular polymeric substances（EPS） with bioflocculation and introducing kinetic model of organic pollutant degradation into EPS, the kinetic model of organic pollutant degradation for step-A hioflocculation was deducted. And through the experiments, the kinetic constants were calculated as follows： k1 =0. 005 3; kc1 =1 710.7 and vmax1=10 min^-1.
基金Project(2006BAJ02A10) supported by the National Key Technologies R & D Program of China
文摘By conducting experimental measurements and numerical simulations of air distribution and microorganism pollutant distribution in the auditorium and game area in a gymnasium,pollutant dispersion control and indoor air quality improvement methods were put forward. The results show that the fungi and bacteria concentration levels are less than the magnitude of 103 CFU (colony-forming units) which meets the requirements of indoor air quality standard. The numerical simulation results quantitatively agree with the experimental data while some differences between theoretical data and experimental data exist in air distributions. People number in gymnasium plays an important role in affecting indoor air quality and the environmental parameters attained the standard.
文摘This essay briefly introduces the historical development of gas chromatography and mass spectrometry technology,it combines important results of GC and GC-MS in environmental monitoring,GC and GC-MS may analyse Polynuclear aromatic hydrocarbons,Pesticide,PCBs,PDBEs and Multicomposit ion of organic pollutants,etc.It also elaborates the developing trend of the gas chromatography technology.
基金Supported by the Special Fund for Agro-scientific Research in Public Interest in China(201503119-06-01)。
文摘In order to explore the remediation effects of lignite and biochar on Zn-contaminated soil,this experiment studied the impacts of adding lignite and biochar on soil respiration,soil enzyme activity,and organic carbon in Zn-contaminated soil through soil culture experiments,which provided a theoretical basis for the remediation and improvement as well as for the development and utilization of Zn-contaminated soil.The study was an L8(4×2^(2))orthogonal experimental design with eight treatments,in which there were four levels of Zn contamination concentration(Z0:0;Z1:125 mg•kg^(-1);Z2:250 mg•kg^(-1);Z3:500 mg•kg^(-1)),low-Zn(125-250 mg•kg^(-1))and high-Zn(500 mg•kg^(-1)),two levels of lignite(H0:0;H1:13.33 g•kg^(-1)),two levels of biochar(C0:0;C1:3.33 g•kg^(-1)),with four replicates per treatment.The results showed that lignite or biochar and their interaction had extremely significant effects on both respiration rate and accumulation in Zn-contaminated soil.Among the high Zn-contaminated treatments,the mixed application of lignite and biochar(Z3H1C1 treatment)had the fastest soil respiration rate and the highest soil respiration accumulation.Lignite,biochar and their interaction had significant or extremely significant effects on sucrase,catalase and polyphenol oxidase activities in Zn-contaminated soil.Among the high Zn-contaminated treatments(Z3),the addition of biochar alone had the most significant effects on the increase of soil sucrase and catalase enzyme activities,while the mixed application of lignite and biochar had the most significant effects on the increase of soil polyphenol oxidase activity.Lignite,biochar and their interaction had significant or extremely significant effects on the total organic carbon,active organic carbon and microbial carbon content of Zn-contaminated soils.Soil total organic carbon content in general peaked at day 80.Among the high Zn-contaminated treatments,the addition of biochar alone had the most significant effects on the total organic carbon content of the soil,while the mixed application of lignite and biochar had the most significant effect on the microbiomass carbon content.
文摘The aerosols has been collected by sample of high-volume sampler in Beijing,and the concentrations of n-alkane in aerosol samples were determined via GC-MS.The n-alkane homolog was from C10 to C33.The total concentrations of n-alkanes in aerosol of Beijing varied from 176.22 to 5 410.2 ng/m3 in PM10 and from 77.89 to 3 138.9 ng/m3 in PM2.5,respectively,during the year and were higher in winter time than those in the other three season.The carbon numbers of main peaks of n-alkanes were 25,27,29 in spring,and 27,29,31 in summer,27,29 in autumn,25 in winter for PM10 samples,respectively.CPI in four seasons was close to 1.0,which indicated that n-alkanes were mainly from combustion of fossil fuel like petroleum,partially from advanced plants.
文摘It′s very useful tools for an instant analysis of organic pollutants monitoring using the HAPSITE portable GC-MS.It discusses how to use HAPSITE portable GC-MS in emergency monitoring and treatment.
文摘The application of photocatalytic technology in H_(2) production,CO_(2) reduction,H_(2)O_(2) production,and pollutant degradation provides a promising approach to the alleviation of energy shortage and environmental issues 1-3.However,hindered by the easy recombination of electron-hole pairs,single-component photocatalysts usually exhibit inferior performance.Constructing heterojunction photocatalysts is a valid method which can improve charge separation and attain high catalytic efficiencies4.
基金Projects(51476069,51676084)supported by the National Natural Science Foundation of ChinaProject(2019C058-3)supported by the Jilin Provincial Industrial Innovation Special Guidance Fund Project,China+1 种基金Project(20180101059JC)supported by the Jilin Provincial Science and Technology Development Plan Project,ChinaProject(2020C025-2)supported by the Jilin Provincial Specific Project of Industrial Technology Research&Development,China。
文摘Oxygen fuels have broad application prospects and great potential for realizing efficient and clean combustion,and hence this study applies diesel/n-butanol blends to explore the influence of split-injection strategy on combustion and emission characteristics.Simultaneously,changing the way of exhaust gas recirculation(EGR)gas introduction forms uneven in-cylinder components distribution,and utilizing EGR stratification optimizes the combustion process and allows better emission results.The results show that the split-injection strategy can reduce the NO_(x)emissions and keep smoke opacity low compared with the single injection,but the rise in accumulation mode particles is noticeable.NO_(x)emissions show an upward trend as the injection interval expands,while soot emissions are significantly reduced.The increase in pre-injection proportion causes the apparent low-temperature heat release,and the two-stage heat release can be observed during the process of main combustion heat release.More pre-injection mass makes NO_(x)gradually increase,but smoke opacity reaches the lowest point at 15%pre-injection proportion.EGR stratification can optimize the emission results under the split injection strategy,especially the considerable suppression of accumulation mode particulate emissions.Above all,fuel stratification coupled with EGR stratification is beneficial for further realizing the in-cylinder purification of pollutants.
基金National Natural Science Foundation of China(21322705,41121004,21190051,and 21177091)
文摘The mechanism of health effects caused by organohalogen pollutants, e.g., toxins from electronic waste(e-waste), is poorly understood. We supposed that micro RNAs(mi RNAs), an important post-transcriptional regulator, could play a role in this process. In this study, fasting peripheral blood samples were collected from residents living at an e-waste site in northern China and a nearby reference population. Concentrations of e-waste related organohalogen pollutants in plasma from the exposure group were higher than the corresponding measurement in the reference group. Correspondingly, sixty mi RNAs in plasma showed > 2-fold change between the two groups in microarray analysis. Among them, mi R-125a-5p was confirmed to be upregulated by q RT-PCR and its validated targets were enriched in responses to xenobiotics and cancer related pathways. Furthermore, significant positive correlations were found between levels of mi R-125a-5p in plasma and reactive oxygen species(ROS) in polymorphonuclear neutrophil leukocytes(P < 0.05). These evidences suggested oxidative stress might be an intermediate between e-waste related POPs exposure and alteration of plasma mi RNA.
基金Project(51204074)supported by the National Natural Science Foundation of ChinaProjects(2010009017,201209048,ZX021-201106-031)supported by the National Environmental Protection Public Welfare Industry Targeted Research Fund,China
文摘Soil cadmium(Cd)contamination resulted from mining and smelting is a major environmental concern,and health risk associated with Cd exposure to multi-media through muti-pathway is increasing.Cd concentrations in soils,vegetables and paddy rice were investigated,and potential non-carcinogenic and carcinogenic health risks exposure to Cd were estimated at six villages around the Dabaoshan Mine,South China.A total of 87 soil samples were found to exceed the China's maximum permission level(MPL)for Cd,while the highest value of 4.42 mg/kg was found near irrigation ditch associated with Hengshi River in Xinyi(XY)Village.Cd contents in vegetables and rice exceeded the maximum permissible concentration by more than five times in every village.Cadmium accumulation in plants is in the order of celery>lactuca sativa L>Chinese cabbage>Romaine lettuce>asparagus lettuce>mustard>cabbage mustard>cabbage.The mean hazard quotient(HQ)of all villages is in the range of [5.29,25.75],and the mean values of cancer risk for investigated areas are more than 10 times greater than the USEPA(2009)threshold limit value of 10-4.Moreover,human non-carcinogenic and carcinogenic risks are mainly attributable to paddy rice intake,followed by vegetables intake,soil ingestion,inhalation,and dermal contact.The results indicate that Cd has a huge potential risk on human health for the local residents.
文摘Eleven plant species were collected from the vicinity of lead-battery plant in the city of Gaziantep,Turkey.Lead,cadmium and copper concentrations in the soil and leaves of plants were determined by atomic absorption spectrometry.Lead,Cd and Cu concentrations in the soil samples taken from battery area were found to be in the ranges of 304～602,0.4～0.44 and 31～37 mg·kg-1,respectively.Significantly increased lead concentration up to 2 750 mg·kg-1 was found in the leaves of Eleagnus angustifolia L.plant.The lead concentrations in the other plant leaves taken from 50 m around battery factory followed the order Ailanthus altissima>Morus sp.>Juglans regia L.>Ficus carica L.>Cydonia oblonga Miller>Prunus x domestica L.The plants,Populus nigra L.,Eleagnus angustifolia L.and Salix sp.were found useful for Cd,and the plant,Eleagnus angustifolia L.for Pb,to be considered as potential biomonitor.Especially,leaves of trees and plants taken from the distance of 50 m from battery plant have relatively higher Pb concentrations.Therefore,people who and animals which live in this area and benefit from these soil and plants have vital risks.
基金Project(51874016)supported by the National Natural Science Foundation of China。
文摘In order to control the dust pollution produced by air leg rock drill in the trolley area during the excavation of long-distance single ended tunnel,the full-scale physical model of working face was established by using FLUENT software,and the numerical simulation analysis of tunnel drilling ventilation and dust removal parameters was carried out.The results show that it is difficult to control the dust pollution of the face by conventional ventilation,and the drilling dust is distributed in the range of 10 m from the face;after the introduction of the long pressure and short suction ventilation scheme,when the ratio of compressed air volume to exhaust air volume is 0.72,the height of the pressure fan is 2.5 m,the distance between the pressure fan and the palm face is 20 m,and the exhaust fan is 12 m away from the palm,the dust concentration control efficiency of the working face is increased by about 60%.Therefore,in the similar long-distance single head tunnel construction,it is appropriate to adopt the dust removal method of long-distance short suction and exhaust fan to ensure the working environment.
