Objective The study aim was to investigate the effects of exposure to multiple environmental organic pollutants on cardiopulmonary health with a focus on the potential mediating role of oxidative stress.Methods A repe...Objective The study aim was to investigate the effects of exposure to multiple environmental organic pollutants on cardiopulmonary health with a focus on the potential mediating role of oxidative stress.Methods A repeated-measures randomized crossover study involving healthy college students in Beijing was conducted. Biological samples, including morning urine and venous blood, were collected to measure concentrations of 29 typical organic pollutants, including hydroxy polycyclic aromatic hydrocarbons(OH-PAHs), bisphenol A and its substitutes, phthalates and their metabolites, parabens,and five biomarkers of oxidative stress. Health assessments included blood pressure measurements and lung function indicators.Results Urinary concentrations of 2-hydroxyphenanthrene(2-OH-PHE)(β = 4.35% [95% confidence interval(CI): 0.85%, 7.97%]), 3-hydroxyphenanthrene(β = 3.44% [95% CI: 0.19%, 6.79%]), and 4-hydroxyphenanthrene(4-OH-PHE)(β = 5.78% [95% CI: 1.27%, 10.5%]) were significantly and positively associated with systolic blood pressure. Exposures to 1-hydroxypyrene(1-OH-PYR)(β = 3.05% [95% CI:-4.66%,-1.41%]), 2-OH-PHE(β = 2.68% [95% CI:-4%,-1.34%]), and 4-OH-PHE(β = 3% [95% CI:-4.68%,-1.29%]) were negatively associated with the ratio of forced expiratory volume in the first second to forced vital capacity. These findings highlight the adverse effects of exposure to multiple pollutants on cardiopulmonary health. Biomarkers of oxidative stress, including 8-hydroxy-2'-deoxyguanosine and extracellular superoxide dismutase, mediated the effects of multiple OH-PAHs on blood pressure and lung function.Conclusion Exposure to multiple organic pollutants can adversely affect cardiopulmonary health.Oxidative stress is a key mediator of the effects of OH-PAHs on blood pressure and lung function.展开更多
Conductive elastomers combining micromechanical sensitivity,lightweight adaptability,and environmental sustainability are critically needed for advanced flexible electronics requiring precise responsiveness and long-t...Conductive elastomers combining micromechanical sensitivity,lightweight adaptability,and environmental sustainability are critically needed for advanced flexible electronics requiring precise responsiveness and long-term wearability;however,the integration of these properties remains a significant challenge.Here,we present a biomass-derived conductive elastomer featuring a rationally engineered dynamic crosslinked network integrated with a tunable microporous architecture.This structural design imparts pronounced micromechanical sensitivity,an ultralow density(~0.25 g cm^(−3)),and superior mechanical compliance for adaptive deformation.Moreover,the unique micro-spring effect derived from the porous architecture ensures exceptional stretchability(>500%elongation at break)and superior resilience,delivering immediate and stable electrical response under both subtle(<1%)and large(>200%)mechanical stimuli.Intrinsic dynamic interactions endow the elastomer with efficient room temperature self-healing and complete recyclability without compromising performance.First-principles simulations clarify the mechanisms behind micropore formation and the resulting functionality.Beyond its facile and mild fabrication process,this work establishes a scalable route toward high-performance,sustainable conductive elastomers tailored for next-generation soft electronics.展开更多
In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and cha...In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change.Likewise,this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa.By leveraging a large volume of climate model outputs,numerous studies have investigated the model representation of African precipitation as well as underlying physical processes.These studies have assessed whether the physical processes are well depicted and whether the models are fit for informing mitigation and adaptation strategies.This paper provides a review of the progress in precipitation simulation overAfrica in state-of-the-science climate models and discusses the major issues and challenges that remain.展开更多
Extracellular polymeric substances （EPS） are the predominant constituents of activated sludge and represent up to 80% of the mass of activated sludge. They play a crucial role in the flocculation, settling and dewat...Extracellular polymeric substances （EPS） are the predominant constituents of activated sludge and represent up to 80% of the mass of activated sludge. They play a crucial role in the flocculation, settling and dewatering of activated sludge. Furthermore, EPS also show great efficiency in binding heavy metals. So EPS are key factors influencing reduction in sludge volume and mass, as well as activity and utilization of sludge. EPS are of considerable environmental interest and hundreds of articles on EPS have been published abroad, while information on EPS in China is limited. In this paper, results of over 60 publications related to constituents and characteristics of EPS and their influences on flocculation, settling and dewatering of sludge are compiled and analyzed. Metal-binding ability of EPS is also discussed, together with a brief consideration of possible research interests in the future.展开更多
Catalytic nickel was successfully incorporated into nanoscale iron to enhance its dechlorination efficiency for trichloroethylene （TCE）, one of the most commonly detected chlorinated organic compounds in groundwater...Catalytic nickel was successfully incorporated into nanoscale iron to enhance its dechlorination efficiency for trichloroethylene （TCE）, one of the most commonly detected chlorinated organic compounds in groundwater. Ethane was the predominant product. The greatest dechlorination efficiency was achieved at 22 molar percent of nickel. This nanoscale Ni-Fe is poorly ordered and inhomogeneous; iron dissolution occurred whereas nickel was relatively stable during the 24-hr reaction. The morphological characterization provided significant new insights on the mechanism of catalytic hydrodcchlorination by bimetallic nanoparticles. TCE degradation and ethane production rates were greatly affected by environmental parameters such as solution pH, temperature and common groundwater ions. Both rate constants decreased and then increased over the pH range of 6.5 to 8.0, with the minimum value occurring at pH 7.5. TCE degradation rate constant showed an increasing trend over the temperature range of 10 to 25℃. However, ethane production rate constant increased and then decreased over the range, with the maximum value occurring at 20℃, Most salts in the solution appeared to enhance the reaction in the first half hour but overall they displayed an inhibitory effect. Combined ions showed a similar effect as individual salts.展开更多
We applied the model of American Meteorological Society-Environmental Protection Agency Regulatory Model（AERMOD） as a tool for the analysis of nitrogen dioxide（NO2） emissions from a cement complex as a part of the...We applied the model of American Meteorological Society-Environmental Protection Agency Regulatory Model（AERMOD） as a tool for the analysis of nitrogen dioxide（NO2） emissions from a cement complex as a part of the environmental impact assessment.The dispersion of NO2 from four cement plants within the selected cement complex were investigated both by measurement and AERMOD simulation in dry and wet seasons.Simulated values of NO2 emissions were compared with those obtained during a 7-day continuous measurement campaign at 12 receptors.It was predicted that NO2 concentration peaks were found more within 1 to 5 km,where the measurement and simulation were in good agreement,than at the receptors 5 km further away from the reference point.The QuantileQuantile plots of NO2 concentrations in dry season were mostly fitted to the middle line compared to those in wet season.This can be attributed to high NO2 wet deposition.The results show that for both the measurement and the simulation using the AERMOD,NO2 concentrations do not exceed the NO2 concentration limit set by the National Ambient Air Quality Standards（NAAQS） of Thailand.This indicates that NO2 emissions from the cement complex have no significant impact on nearby communities.It can be concluded that the AERMOD can provide useful information to identify high pollution impact areas for the EIA guidelines.展开更多
The environment of estuarine wetlands has been attracting worldwide attention. To study the spatial distribution of pollutants in the tidal flats of the Yangtze Estuary, Southeast China, the Eastern Tidal Flat of Chon...The environment of estuarine wetlands has been attracting worldwide attention. To study the spatial distribution of pollutants in the tidal flats of the Yangtze Estuary, Southeast China, the Eastern Tidal Flat of Chongming Island (EC) and the Jiuduansha Shoal (JS) of the estuary were selected as the study sites. At each of the two sites, a cross-transect from land to sea was established and topsoil and soil core samples in the cross-transect were collected spatially and seasonally to determine their contents of heavy metals (Cu, Zn, Pb, Cd, Cr, Ni, Mn, and Fe) and grain-size characteristics. The results showed that the heavy metal loads were commonly higher in the soils of nearshore high tidal flats and had a tendency of decreasing from land to sea at both of the study sites. The contents of heavy metals in the soils of the high and medial tidal flats were mostly higher in April and November but lower in July. Corresponding spatial and seasonal variations in grain size of the intertidal soils were also observed at the two study sites. The soils in the nearshore high tidal flats were finer and gradually got coarser seawards; they were relatively finer in April and November but coarser in July. Furthermore, the contents of heavy metals in the intertidal soils of both the sites EC and JS were significantly positively correlated with the clay (<2 μm) and 2-20 μm fractions, but negatively with the sand (>63 μm) and 20-63 μm fractions, which suggested that the heavy metals in the intertidal soils were primarily combined with the fine particulate fraction (<20 μm), especially clay, and hence the spatial and seasonal variations in heavy metals were actually caused by the change of the grain-size characteristics of the intertidal soils due to the different sedimentary environments in the estuary. The results of this study may also contribute to a better understanding of the soil formation and classification in the tidal flats of the Yangtze Estuary.展开更多
Pedogenic carbonates, found extensively in arid and semiarid regions, are important in revealing regional climatic and environmental changes as well as the carbon cycle. In addition, stable carbon and oxygen isotopic ...Pedogenic carbonates, found extensively in arid and semiarid regions, are important in revealing regional climatic and environmental changes as well as the carbon cycle. In addition, stable carbon and oxygen isotopic compositions of pedogenic carbonates have been used to rebuild paleoecology (biomass and vegetation) and to estimate paleotemperature and paleoprecipitation during past geological time. By utilizing the stable carbon and oxygen isotopic compositions (δ13C and (δ18O) of secondary nodules in Ustic Vertisols, this study looked into the climatic and environmental changes in the dry valleys of the Yuanmou Basin, Yunnan Province, in southwestern China. The results showed that during the early Holocene, a warm-humid or hot-humid climate existed in the Yuanmou Basin, but since then fluctuations in climate have occurred, with a dry climate prevailing. A highly significant correlation (r = 0.92, n = 9) between δ13C and δ18O values of carbonates illustrated that there had been a continual shifting between cold-humid and warm-dry climates in southwestern China including the Yuanmou Basin since the early Holocene.展开更多
Continuous seismic observations can record seismic waveforms, and ambient noise, for the purposes of earthquake researches and other applications. Here we deploy three digital seismometers(EPS-2) in and around the Nan...Continuous seismic observations can record seismic waveforms, and ambient noise, for the purposes of earthquake researches and other applications. Here we deploy three digital seismometers(EPS-2) in and around the Nanwangshan Campus of the China University of Geosciences(Wuhan). This network was running from April 9 to May 9 of 2018. During this period, the seismometers recorded the May 4, 2018 M6.9 Hawaii earthquake. From the recorded waveforms, we could observe clearly the P and S arrivals, and the corresponding particle motions. Analysis of continuous observations of ambient noise shows obvious fluctuation of vibration intensity inside of the campus. The campus is quietest from 0 to 5 am. From 5 am on, the vibration intensity increases, and reaches the peak of entire day at 12 am. The amplitude then decreases to a very low level at 19:30 to 20:00 pm, and reaches another strong noisy time at 21:00 to 21:30 pm. After 21:30 pm, the intensity goes down slowly. We also observed seismic signals that were generated by the interaction of speed-control hump cars and ground. By taking the envelope and smooth operations, we observe different characteristics for different car speeds, which suggests that seismic monitoring approaches can be used for speed measurement of cars. This kind of small seismic network running in a real time fashion, would greatly help understanding of the sources of ambient noise at high frequency bands in interested areas. Analysis of a long-term observed dataset, and real time illustration will help to strengthen campus security and high-precision laboratory deployments, and also contribute to research atmosphere in earthquake science.展开更多
The Swan Lake Inlet, the State Primary Wildlife Protection Area, is a lagoon\|inlet system located in the Rongcheng Bay, Shandong Peninsula, China. It has been undergoing development for aquaculture and tourism. In th...The Swan Lake Inlet, the State Primary Wildlife Protection Area, is a lagoon\|inlet system located in the Rongcheng Bay, Shandong Peninsula, China. It has been undergoing development for aquaculture and tourism. In the summer of 1999, a study on the environment of the Swan Lake Inlet was carried out. The concentrations of the major elements and trace elements Fe, Al, Pb, Zn, Cd, Cu, Cr, Mn and P have been measured by ICP\|AES and graphite furnace atomic adsorption spectrometry. The sources and distribution of the elements in the Swan Lake Inlet have been discussed. It is concluded that the Swan Lake Inlet has not been subjected to significant environmental pollution.\; The chemical results show that the dissolved oxygen (DO) contents are generally normal. At some locations DO solubility appears to be >100%. The BOD\-5 (five\|day biochemical oxygen demand) values are generally <4 mg/L and COD (chemical oxygen demand) 3～4 mg/L. The seawater N, P and Si contents are lower than the Class I water type specified by the Chinese National Standard of Water Quality. The low nutrient distribution reflects little discharge from land, therefore lacking of nutrient supply.展开更多
The metamorphic belt in central Jiangxi, located in the compound terrain within the Cathaysia, Yangtze Block and Caledonian fold zone of South China, is composed dominantly of meta-argillo-arenaceous rocks, with minor...The metamorphic belt in central Jiangxi, located in the compound terrain within the Cathaysia, Yangtze Block and Caledonian fold zone of South China, is composed dominantly of meta-argillo-arenaceous rocks, with minor amphibolite. These rocks underwent amphibolite-facies metamorphism. The meta-argillo-arenaceous rocks show large variations in major element composition, but have similar REE patterns and trace element composition, incompatible element and LIE enrichments [high Th/Sc ({0.57}-{3.59}), La/Sc ({1.46}-{12.4}), La/Yb ({5.84}-{19.0})] and variable Th/U ratios, with ΣREE=129-296μg/g, δEu={0.51}-{0.86}, and (La/Yb)-N={3.95}-{12.9}. The Nd isotopic model ages t-{DM} of these rocks vary from 1597 to 2124 Ma. Their {}+{143}Nd/+{144}Nd values are low [ε-{Nd}(0)={-11.4} to {-15.8}]. Some conclusions have been drawn as follows: (1) The metamorphic rocks in central Jiangxi Province are likely formed in a tectonic environment at the passive continental margin of the Cathaysia massif. (2) The metamorphosed argillo-arenaceous rocks are composed dominantly of upper crustal-source rocks (Al- and K|rich granitic or/and sedimentary rocks of Early Proterozoic), which experienced good sorting, slow deposition and more intense chemical weathering. (3) According to the whole-rock Sm-Nd isochron ages (1113±49 to 1199±26 Ma) of plagioclase-amphibole (schist) and Nd isotopic model age t-{DM} (1597-2124 Ma) of meta-argillo-arenaceous rocks, the metamorphic belt in central Jiangxi Province was formed during the Middle Proterozoic (1100-1600 Ma).展开更多
The coronavirus disease 2019(COVID-19)pandemic is challenging the current public health emergency response systems(PHERSs)of many countries.Although environmental factors,such as those influencing the survival of viru...The coronavirus disease 2019(COVID-19)pandemic is challenging the current public health emergency response systems(PHERSs)of many countries.Although environmental factors,such as those influencing the survival of viruses and their transmission between species including humans,play important roles in PHERSs,little attention has been given to these factors.This study describes and elucidates the roles of environmental factors in future PHERSs.To improve countries’capability to respond to public health emergencies associated with viral infections such as the COVID-19 pandemic,a number of environmental factors should be considered before,during,and after the responses to such emergencies.More specifically,to prevent pandemic outbreaks,we should strengthen environmental and wildlife protection,conduct detailed viral surveillance in animals and hotspots,and improve early-warning systems.During the pandemic,we must study the impacts of environmental factors on viral behaviors,develop control measures to minimize secondary environmental risks,and conduct timely assessments of viral risks and secondary environmental effects with a view to reducing the impacts of the pandemic on human health and on ecosystems.After the pandemic,we should further strengthen surveillance for viruses and the prevention of viral spread,maintain control measures for minimizing secondary environmental risks,develop our capability to scientifically predict pandemics and resurgences,and prepare for the next unexpected resurgence.Meanwhile,we should restore the normal life and production of the public based on the“One Health”concept,that views global human and environmental health as inextricably linked.Our recommendations are essential for improving nations’capability to respond to global public health emergencies.展开更多
Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment mon...Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment monitoring stations for NMHCs and 20 OVOC species were analyzed.Significant seasonal differences were noted for total VOC(TVOC,NMHCs and OVOCs)concentrations and compositions.The campaign-average TVOC concentrations in winter(85.3±60.6 ppbv)were almost twice those in summer(47.2±31.6 ppbv).Alkanes and OVOCs were the most abundant category in winter and summer,respectively.NMHCs,but not OVOCs,had significantly higher levels on weekends than on weekdays.Total ozone formation potential was higher in summer than in winter(by 50%)because of the high concentrations of alkenes(particularly isoprene),high temperature,and high solar radiation levels in summer.The Hybrid Environmental Receptor Model(HERM)was used to conduct source apportionment for atmospheric TVOCs in winter and summer,with excellent accuracy.HERM demonstrated its suitability in a situation where only partial source profile data were available.The HERM results indicated significantly different seasonal source contributions to TVOCs in Xi’an.In particular,coal and biomass burning had contributions greater than half in winter(53.4%),whereas traffic sources were prevalent in summer(53.1%).This study’s results highlight the need for targeted and adjustable VOC control measures that account for seasonal differences in Xi’an;such measures should target not only the severe problem with VOC pollution but also the problem of consequent secondary pollution(e.g.,from ozone and secondary organic aerosols).展开更多
Healthcare workers(HCWs)are at high risk of occupational exposure to the new pandemic human coronavirus,SARSCoV-2,and are a source of nosocomial transmission in airborne infectious isolation rooms(AIIRs).Here,we perfo...Healthcare workers(HCWs)are at high risk of occupational exposure to the new pandemic human coronavirus,SARSCoV-2,and are a source of nosocomial transmission in airborne infectious isolation rooms(AIIRs).Here,we performed comprehensive environmental contamination surveillance to evaluate the risk of viral transmission in AIIRs with 115 rooms in three buildings at the Shanghai Public Health Clinical Center,Shanghai,during the treatment of 334 patients infected with SARS-CoV-2.The results showed that the risk of airborne transmission of SARS-CoV-2 in AIIRs was low(1.62%,25/1544)due to the directional airflow and strong environmental hygiene procedures.However,we detected viral RNA on the surface of foot-operated openers and bathroom sinks in AIIRs(viral load:55.00–3154.50 copies/mL).This might be a source of contamination to connecting corridors and object surfaces through the footwear and gloves used by HCWs.The risk of infection was eliminated by the use of disposable footwear covers and the application of more effective environmental and personal hygiene measures.With the help of effective infection control procedures,none of 290 HCWs was infected when working in the AIIRs at this hospital.This study has provided information pertinent for infection control in AIIRs during the treatment of COVID-19 patients.展开更多
The study evaluated the sources and controlling factors of the groundwater contaminants in an agroeconomic region of Lower Ganga Basin using principal component analysis(PCA),multivariable linear regressions(MLR),corr...The study evaluated the sources and controlling factors of the groundwater contaminants in an agroeconomic region of Lower Ganga Basin using principal component analysis(PCA),multivariable linear regressions(MLR),correlation analysis,and hierarchical cluster analysis,and evaluated the public health risks using the Latin Hypercube Sampling,goodness-of-fit statistics,Monte Carlo simulation and Sobol sensitivity analysis based on the 1000 samples collected in two sampling cycles(N=1000).The study reveals that the dissolution of fluoride-bearing minerals and semi-arid climate regulate the fluoride concentrations(0.10–18.25 mg/L)in groundwater.Extensive application of inorganic nitrogenous fertilizers and livestock manure mainly contributed to elevated nitrate levels(up to 435.0 mg/L)in groundwater.The health risks analysis indicates that fluoride exposure is more prevalent in the residents of each age group than the nitrate and both contaminants exhibited higher non-carcinogenic health risks on the infant and child(minor)age groups compared to adolescents and adults.Based on the cokriging interpolation mapping,the minor residents of 17.88%–23.15%of the total area(4545.0 km^(2))are vulnerable to methemoglobinemia whereas the residents of all age-groups in 38.47%–44.45%of the total area are susceptible to mild to severe dental/skeletal fluorosis owing to consumption of untreated nitrate and fluoride enriched groundwater.The Sobol sensitivity indices revealed contaminant levels,groundwater intake rate and their collective effects are the most influential factors to pose potential health risks on the residents.Artificial recharge and rainwater harvesting practices should be adopted to improve the groundwater quality and the residents are advised to drink purified groundwater.展开更多
Modern logistics is a new industry during the construction of national economy. Based on analyzing the environmental problem that was led by the limitation of the strategy during enacting the program of the modern log...Modern logistics is a new industry during the construction of national economy. Based on analyzing the environmental problem that was led by the limitation of the strategy during enacting the program of the modern logistics, SEA for modern logistics was implemented. In this paper, procedure and indicator system in the SEA are constructed, and Environmental Check List to identify environmental impact factors of SEA for modern logistics is established. And a conception that indicates friendly degree of logistics system with resources and environment, degree of green, is introduced. With the example of modern logistics program of Dalian in China, two methods are applied, AHP and Fuzzy Comprehensive Evaluation Method, in the implement of SEA for modern logistics development. It is concluded that degree of green of modern logistics in Dalian is high. However, several important factors should be paid much attention to in the SEA for modern logistics as well as in the formulation and implement of modern logistics in Dalian.展开更多
Cyanobacteria can accumulate as a heavy biomass on the leeward side of large eutrophic lakes,posing a potential threat to public health.The mitigating capacity of three flocculants and their potential impacts on the m...Cyanobacteria can accumulate as a heavy biomass on the leeward side of large eutrophic lakes,posing a potential threat to public health.The mitigating capacity of three flocculants and their potential impacts on the major environmental features of water and sediments was evaluated.Results indicate that polyaluminum chloride(PAC)and ferric chloride(FeCl)are efficient flocculants that can rapidly mitigate cyanobacterial blooms with chlorophyll-a concentrations higher tnan 1500 ug/L within 15 min.In comparison,cationic starch with chitosan could only treat cyanobacterial blooms in chlorophyll-a concentrations of less than 200μg/L.The addition of FeClcaused a decline in the pH value,while dissolved oxygen in the water column dropped to 2 mg/L during cationic starch with chitosan treatment for a high cyanobacterial biomass group.Thus,a combination of flocculants and oxygenators should be considered when treating high-concentration cyanobacterial blooms for emergency purposes.Additionally,the cell lysis of cyanobacteria caused by cationic starch with chitosan can result in an increase in total dissolved phosphorus and total dissolved nitrogen.Furthermore,the high accumlation of nutrients in sediments after the settling of cyanobacteria can cause high internal phosphorus pollution.The increase in the total organic carbon of the sediments can threaten lake restoration achieved by planting submerged macrophytes.展开更多
In this study, salting-out assisted liquid-liquid extraction combined with high performance liquid chromatography diode array detector (SALLE-HPLC-DAD) method was developed and validated for simultaneous analysis of c...In this study, salting-out assisted liquid-liquid extraction combined with high performance liquid chromatography diode array detector (SALLE-HPLC-DAD) method was developed and validated for simultaneous analysis of carbaryl, atrazine, propazine, chlorothalonil, dimethametryn and terbutryn in environmental water samples. Parameters affecting the extraction efficiency such as type and volume of extraction solvent, sample volume, salt type and amount, centrifugation speed and time, and sample pH were optimized. Under the optimum extraction conditions the method was linear over the range of 10 - 100 μg/L (carbaryl), 8 - 100 μg/L (atarzine), 7 - 100 μg/L (propazine) and 9 - 100 μg/L (chlorothalonil, terbutryn and dimethametryn) with correlation coefficients (R2) between 0.99 and 0.999. Limits of detection and quantification ranged from 2.0 to 2.8 μg/L and 6.7 to 9.5 μg/L, respectively. The extraction recoveries obtained for ground, lake and river waters were in a range of 75.5% to 106.6%, with the intra-day and inter-day relative standard deviation lower than 3.4% for all the target analytes. All of the target analytes were not detected in these samples. Therefore, the proposed SALLE-HPLC-DAD method is simple, rapid, cheap and environmentally friendly for the determination of the aforementioned herbicides, insecticide and fungicide residues in environmental water samples.展开更多
The coronavirus disease 2019(COVID-19)pandemic,caused by the novel virus severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),began in December 2019 in China and has led to a global public health emergency.Prev...The coronavirus disease 2019(COVID-19)pandemic,caused by the novel virus severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),began in December 2019 in China and has led to a global public health emergency.Previously,it was known as 2019-nCoV and caused disease mainly through respiratory pathways.The COVID-19 outbreak is ranked third globally as the most highly pathogenic disease of the twenty-first century,after the outbreak of SARS-CoV and Middle East respiratory syndrome in 2002 and 2012,respectively.Clinical,laboratory,and diagnostic methodology have been demonstrated in some observational studies.No systematic reviews on COVID-19 have been published regarding the integration of COVID-19 outbreaks(monitoring,fate and treatment)with environmental and human health perspectives.Accordingly,this review systematically addresses environmental aspects of COVID-19 outbreak such as the origin of SARS-CoV-2,epidemiological characteristics,diagnostic methodology,treatment options and technological advancement for the prevention of COVID-19 outbreaks.Finally,we integrate COVID-19 outbreaks(monitoring,fate and treatment)with environmental and human health perspectives.We believe that this review will help to understand the SARS-CoV-2 outbreak as a multipurpose document,not only for the scientific community but also for global citizens.Countries should adopt emergency preparedness such as prepare human resources,infrastructure and facilities to treat severe COVID-19 as the virus spreads rapidly globally.展开更多
The present paper deals with the behavior of the Attached Microbial Community (AMC) for water self-purification at different riverbeds in a typical local river. The study quantitatively investigated the problem starti...The present paper deals with the behavior of the Attached Microbial Community (AMC) for water self-purification at different riverbeds in a typical local river. The study quantitatively investigated the problem starting with in-situ sampling. It was found that more biomass of AMC was at riffles with wider distribution than in pools. High current velocity (HCV) plays a negative role at the initial stage of attachment on the riverbed, but HCV aids the community proliferation after stable attachment. External disturbances such as rainfalls and discharges from dams or reservoirs would detach the periphyton depending on the intensity of turbulence in water. However, it was discovered that the flock of periphyton could be restored very quickly because it was not completely removed. Thus, in order to enhance self-purification by periphyton, a suitable configuration of the riverbed must be constructed, and occasional appropriate repair along the channels would improve the decontamination of the river.展开更多
基金supported by the National Key Research&Development Program of the Ministry of Science and Technology of China(2022YFE0134900,2023YFC3708305,2023YFC3708302)Strategy Priority Research Program(Category B)of the Chinese Academy of Sciences(No.XDB0750300)National Natural Science Foundation of China(Grant No.42477455,42077390).
文摘Objective The study aim was to investigate the effects of exposure to multiple environmental organic pollutants on cardiopulmonary health with a focus on the potential mediating role of oxidative stress.Methods A repeated-measures randomized crossover study involving healthy college students in Beijing was conducted. Biological samples, including morning urine and venous blood, were collected to measure concentrations of 29 typical organic pollutants, including hydroxy polycyclic aromatic hydrocarbons(OH-PAHs), bisphenol A and its substitutes, phthalates and their metabolites, parabens,and five biomarkers of oxidative stress. Health assessments included blood pressure measurements and lung function indicators.Results Urinary concentrations of 2-hydroxyphenanthrene(2-OH-PHE)(β = 4.35% [95% confidence interval(CI): 0.85%, 7.97%]), 3-hydroxyphenanthrene(β = 3.44% [95% CI: 0.19%, 6.79%]), and 4-hydroxyphenanthrene(4-OH-PHE)(β = 5.78% [95% CI: 1.27%, 10.5%]) were significantly and positively associated with systolic blood pressure. Exposures to 1-hydroxypyrene(1-OH-PYR)(β = 3.05% [95% CI:-4.66%,-1.41%]), 2-OH-PHE(β = 2.68% [95% CI:-4%,-1.34%]), and 4-OH-PHE(β = 3% [95% CI:-4.68%,-1.29%]) were negatively associated with the ratio of forced expiratory volume in the first second to forced vital capacity. These findings highlight the adverse effects of exposure to multiple pollutants on cardiopulmonary health. Biomarkers of oxidative stress, including 8-hydroxy-2'-deoxyguanosine and extracellular superoxide dismutase, mediated the effects of multiple OH-PAHs on blood pressure and lung function.Conclusion Exposure to multiple organic pollutants can adversely affect cardiopulmonary health.Oxidative stress is a key mediator of the effects of OH-PAHs on blood pressure and lung function.
基金supported by National Natural Science Foundation of China(No.52103044)Double First-Class Initiative University of Science and Technology of China(KY2400000037)the Young Talent Programme(GG2400007009).
文摘Conductive elastomers combining micromechanical sensitivity,lightweight adaptability,and environmental sustainability are critically needed for advanced flexible electronics requiring precise responsiveness and long-term wearability;however,the integration of these properties remains a significant challenge.Here,we present a biomass-derived conductive elastomer featuring a rationally engineered dynamic crosslinked network integrated with a tunable microporous architecture.This structural design imparts pronounced micromechanical sensitivity,an ultralow density(~0.25 g cm^(−3)),and superior mechanical compliance for adaptive deformation.Moreover,the unique micro-spring effect derived from the porous architecture ensures exceptional stretchability(>500%elongation at break)and superior resilience,delivering immediate and stable electrical response under both subtle(<1%)and large(>200%)mechanical stimuli.Intrinsic dynamic interactions endow the elastomer with efficient room temperature self-healing and complete recyclability without compromising performance.First-principles simulations clarify the mechanisms behind micropore formation and the resulting functionality.Beyond its facile and mild fabrication process,this work establishes a scalable route toward high-performance,sustainable conductive elastomers tailored for next-generation soft electronics.
基金the World Climate Research Programme(WCRP),Climate Variability and Predictability(CLIVAR),and Global Energy and Water Exchanges(GEWEX)for facilitating the coordination of African monsoon researchsupport from the Center for Earth System Modeling,Analysis,and Data at the Pennsylvania State Universitythe support of the Office of Science of the U.S.Department of Energy Biological and Environmental Research as part of the Regional&Global Model Analysis(RGMA)program area。
文摘In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change.Likewise,this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa.By leveraging a large volume of climate model outputs,numerous studies have investigated the model representation of African precipitation as well as underlying physical processes.These studies have assessed whether the physical processes are well depicted and whether the models are fit for informing mitigation and adaptation strategies.This paper provides a review of the progress in precipitation simulation overAfrica in state-of-the-science climate models and discusses the major issues and challenges that remain.
基金The National Natural Science Foundation of China (No. 50578053) and the Harbin Young Scientist Fund (No. 2003AFXXJ025)
文摘Extracellular polymeric substances （EPS） are the predominant constituents of activated sludge and represent up to 80% of the mass of activated sludge. They play a crucial role in the flocculation, settling and dewatering of activated sludge. Furthermore, EPS also show great efficiency in binding heavy metals. So EPS are key factors influencing reduction in sludge volume and mass, as well as activity and utilization of sludge. EPS are of considerable environmental interest and hundreds of articles on EPS have been published abroad, while information on EPS in China is limited. In this paper, results of over 60 publications related to constituents and characteristics of EPS and their influences on flocculation, settling and dewatering of sludge are compiled and analyzed. Metal-binding ability of EPS is also discussed, together with a brief consideration of possible research interests in the future.
基金supported by the National Natural Science Foundation of China(No.20807004)the General Research an Development Founding for Universities directly under the Ministry of Education of China(BUCTZZ1202)
文摘Catalytic nickel was successfully incorporated into nanoscale iron to enhance its dechlorination efficiency for trichloroethylene （TCE）, one of the most commonly detected chlorinated organic compounds in groundwater. Ethane was the predominant product. The greatest dechlorination efficiency was achieved at 22 molar percent of nickel. This nanoscale Ni-Fe is poorly ordered and inhomogeneous; iron dissolution occurred whereas nickel was relatively stable during the 24-hr reaction. The morphological characterization provided significant new insights on the mechanism of catalytic hydrodcchlorination by bimetallic nanoparticles. TCE degradation and ethane production rates were greatly affected by environmental parameters such as solution pH, temperature and common groundwater ions. Both rate constants decreased and then increased over the pH range of 6.5 to 8.0, with the minimum value occurring at pH 7.5. TCE degradation rate constant showed an increasing trend over the temperature range of 10 to 25℃. However, ethane production rate constant increased and then decreased over the range, with the maximum value occurring at 20℃, Most salts in the solution appeared to enhance the reaction in the first half hour but overall they displayed an inhibitory effect. Combined ions showed a similar effect as individual salts.
基金the Royal Golden Jubilee Ph.D program (IUG50K0021)Thailand Research Fund (TRF) for the financial support
文摘We applied the model of American Meteorological Society-Environmental Protection Agency Regulatory Model（AERMOD） as a tool for the analysis of nitrogen dioxide（NO2） emissions from a cement complex as a part of the environmental impact assessment.The dispersion of NO2 from four cement plants within the selected cement complex were investigated both by measurement and AERMOD simulation in dry and wet seasons.Simulated values of NO2 emissions were compared with those obtained during a 7-day continuous measurement campaign at 12 receptors.It was predicted that NO2 concentration peaks were found more within 1 to 5 km,where the measurement and simulation were in good agreement,than at the receptors 5 km further away from the reference point.The QuantileQuantile plots of NO2 concentrations in dry season were mostly fitted to the middle line compared to those in wet season.This can be attributed to high NO2 wet deposition.The results show that for both the measurement and the simulation using the AERMOD,NO2 concentrations do not exceed the NO2 concentration limit set by the National Ambient Air Quality Standards（NAAQS） of Thailand.This indicates that NO2 emissions from the cement complex have no significant impact on nearby communities.It can be concluded that the AERMOD can provide useful information to identify high pollution impact areas for the EIA guidelines.
基金Supported by the National Natural Science Foundation of China (Nos. 41130526, 40971126, and 40771093)the Shanghai Leading Academic Discipline Project of China (No. S30109)
文摘The environment of estuarine wetlands has been attracting worldwide attention. To study the spatial distribution of pollutants in the tidal flats of the Yangtze Estuary, Southeast China, the Eastern Tidal Flat of Chongming Island (EC) and the Jiuduansha Shoal (JS) of the estuary were selected as the study sites. At each of the two sites, a cross-transect from land to sea was established and topsoil and soil core samples in the cross-transect were collected spatially and seasonally to determine their contents of heavy metals (Cu, Zn, Pb, Cd, Cr, Ni, Mn, and Fe) and grain-size characteristics. The results showed that the heavy metal loads were commonly higher in the soils of nearshore high tidal flats and had a tendency of decreasing from land to sea at both of the study sites. The contents of heavy metals in the soils of the high and medial tidal flats were mostly higher in April and November but lower in July. Corresponding spatial and seasonal variations in grain size of the intertidal soils were also observed at the two study sites. The soils in the nearshore high tidal flats were finer and gradually got coarser seawards; they were relatively finer in April and November but coarser in July. Furthermore, the contents of heavy metals in the intertidal soils of both the sites EC and JS were significantly positively correlated with the clay (<2 μm) and 2-20 μm fractions, but negatively with the sand (>63 μm) and 20-63 μm fractions, which suggested that the heavy metals in the intertidal soils were primarily combined with the fine particulate fraction (<20 μm), especially clay, and hence the spatial and seasonal variations in heavy metals were actually caused by the change of the grain-size characteristics of the intertidal soils due to the different sedimentary environments in the estuary. The results of this study may also contribute to a better understanding of the soil formation and classification in the tidal flats of the Yangtze Estuary.
基金Project supported by the National Key Basic Research Support Foundation of China (No. G1998040800).
文摘Pedogenic carbonates, found extensively in arid and semiarid regions, are important in revealing regional climatic and environmental changes as well as the carbon cycle. In addition, stable carbon and oxygen isotopic compositions of pedogenic carbonates have been used to rebuild paleoecology (biomass and vegetation) and to estimate paleotemperature and paleoprecipitation during past geological time. By utilizing the stable carbon and oxygen isotopic compositions (δ13C and (δ18O) of secondary nodules in Ustic Vertisols, this study looked into the climatic and environmental changes in the dry valleys of the Yuanmou Basin, Yunnan Province, in southwestern China. The results showed that during the early Holocene, a warm-humid or hot-humid climate existed in the Yuanmou Basin, but since then fluctuations in climate have occurred, with a dry climate prevailing. A highly significant correlation (r = 0.92, n = 9) between δ13C and δ18O values of carbonates illustrated that there had been a continual shifting between cold-humid and warm-dry climates in southwestern China including the Yuanmou Basin since the early Holocene.
基金the National Key R&D Program of China(No.2018YFC0603500)Programme on Global Change and Air-Sea Interaction(No.GASI-GEOGE-02)+1 种基金NSFC(Nos.41474050,41874062)one of the outcomes of the research projects(No.Q20203004),analysis of campus ambient noise monitored by short-seismometers funded by Scientific Research Foundation of the Education Department of Hubei Province,China。
文摘Continuous seismic observations can record seismic waveforms, and ambient noise, for the purposes of earthquake researches and other applications. Here we deploy three digital seismometers(EPS-2) in and around the Nanwangshan Campus of the China University of Geosciences(Wuhan). This network was running from April 9 to May 9 of 2018. During this period, the seismometers recorded the May 4, 2018 M6.9 Hawaii earthquake. From the recorded waveforms, we could observe clearly the P and S arrivals, and the corresponding particle motions. Analysis of continuous observations of ambient noise shows obvious fluctuation of vibration intensity inside of the campus. The campus is quietest from 0 to 5 am. From 5 am on, the vibration intensity increases, and reaches the peak of entire day at 12 am. The amplitude then decreases to a very low level at 19:30 to 20:00 pm, and reaches another strong noisy time at 21:00 to 21:30 pm. After 21:30 pm, the intensity goes down slowly. We also observed seismic signals that were generated by the interaction of speed-control hump cars and ground. By taking the envelope and smooth operations, we observe different characteristics for different car speeds, which suggests that seismic monitoring approaches can be used for speed measurement of cars. This kind of small seismic network running in a real time fashion, would greatly help understanding of the sources of ambient noise at high frequency bands in interested areas. Analysis of a long-term observed dataset, and real time illustration will help to strengthen campus security and high-precision laboratory deployments, and also contribute to research atmosphere in earthquake science.
基金ThisresearchprojectwasgrantedjointlybytheStartingFundsforBack From AbroadDoctorssponsoredbytheQingdaoUni versityandtheNationalOu
文摘The Swan Lake Inlet, the State Primary Wildlife Protection Area, is a lagoon\|inlet system located in the Rongcheng Bay, Shandong Peninsula, China. It has been undergoing development for aquaculture and tourism. In the summer of 1999, a study on the environment of the Swan Lake Inlet was carried out. The concentrations of the major elements and trace elements Fe, Al, Pb, Zn, Cd, Cu, Cr, Mn and P have been measured by ICP\|AES and graphite furnace atomic adsorption spectrometry. The sources and distribution of the elements in the Swan Lake Inlet have been discussed. It is concluded that the Swan Lake Inlet has not been subjected to significant environmental pollution.\; The chemical results show that the dissolved oxygen (DO) contents are generally normal. At some locations DO solubility appears to be >100%. The BOD\-5 (five\|day biochemical oxygen demand) values are generally <4 mg/L and COD (chemical oxygen demand) 3～4 mg/L. The seawater N, P and Si contents are lower than the Class I water type specified by the Chinese National Standard of Water Quality. The low nutrient distribution reflects little discharge from land, therefore lacking of nutrient supply.
文摘The metamorphic belt in central Jiangxi, located in the compound terrain within the Cathaysia, Yangtze Block and Caledonian fold zone of South China, is composed dominantly of meta-argillo-arenaceous rocks, with minor amphibolite. These rocks underwent amphibolite-facies metamorphism. The meta-argillo-arenaceous rocks show large variations in major element composition, but have similar REE patterns and trace element composition, incompatible element and LIE enrichments [high Th/Sc ({0.57}-{3.59}), La/Sc ({1.46}-{12.4}), La/Yb ({5.84}-{19.0})] and variable Th/U ratios, with ΣREE=129-296μg/g, δEu={0.51}-{0.86}, and (La/Yb)-N={3.95}-{12.9}. The Nd isotopic model ages t-{DM} of these rocks vary from 1597 to 2124 Ma. Their {}+{143}Nd/+{144}Nd values are low [ε-{Nd}(0)={-11.4} to {-15.8}]. Some conclusions have been drawn as follows: (1) The metamorphic rocks in central Jiangxi Province are likely formed in a tectonic environment at the passive continental margin of the Cathaysia massif. (2) The metamorphosed argillo-arenaceous rocks are composed dominantly of upper crustal-source rocks (Al- and K|rich granitic or/and sedimentary rocks of Early Proterozoic), which experienced good sorting, slow deposition and more intense chemical weathering. (3) According to the whole-rock Sm-Nd isochron ages (1113±49 to 1199±26 Ma) of plagioclase-amphibole (schist) and Nd isotopic model age t-{DM} (1597-2124 Ma) of meta-argillo-arenaceous rocks, the metamorphic belt in central Jiangxi Province was formed during the Middle Proterozoic (1100-1600 Ma).
基金the National Science Foundation of China(41925031,41991315,and 41521003).
文摘The coronavirus disease 2019(COVID-19)pandemic is challenging the current public health emergency response systems(PHERSs)of many countries.Although environmental factors,such as those influencing the survival of viruses and their transmission between species including humans,play important roles in PHERSs,little attention has been given to these factors.This study describes and elucidates the roles of environmental factors in future PHERSs.To improve countries’capability to respond to public health emergencies associated with viral infections such as the COVID-19 pandemic,a number of environmental factors should be considered before,during,and after the responses to such emergencies.More specifically,to prevent pandemic outbreaks,we should strengthen environmental and wildlife protection,conduct detailed viral surveillance in animals and hotspots,and improve early-warning systems.During the pandemic,we must study the impacts of environmental factors on viral behaviors,develop control measures to minimize secondary environmental risks,and conduct timely assessments of viral risks and secondary environmental effects with a view to reducing the impacts of the pandemic on human health and on ecosystems.After the pandemic,we should further strengthen surveillance for viruses and the prevention of viral spread,maintain control measures for minimizing secondary environmental risks,develop our capability to scientifically predict pandemics and resurgences,and prepare for the next unexpected resurgence.Meanwhile,we should restore the normal life and production of the public based on the“One Health”concept,that views global human and environmental health as inextricably linked.Our recommendations are essential for improving nations’capability to respond to global public health emergencies.
基金This research was supported by the Natural Science Foundation of China(Grant No.41907188)Natural Science Foundation of Shaanxi Province,China(Grant No.2019JQ-386)the China Postdoctoral Science Foundation(Grant No.2019M653658).
文摘Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment monitoring stations for NMHCs and 20 OVOC species were analyzed.Significant seasonal differences were noted for total VOC(TVOC,NMHCs and OVOCs)concentrations and compositions.The campaign-average TVOC concentrations in winter(85.3±60.6 ppbv)were almost twice those in summer(47.2±31.6 ppbv).Alkanes and OVOCs were the most abundant category in winter and summer,respectively.NMHCs,but not OVOCs,had significantly higher levels on weekends than on weekdays.Total ozone formation potential was higher in summer than in winter(by 50%)because of the high concentrations of alkenes(particularly isoprene),high temperature,and high solar radiation levels in summer.The Hybrid Environmental Receptor Model(HERM)was used to conduct source apportionment for atmospheric TVOCs in winter and summer,with excellent accuracy.HERM demonstrated its suitability in a situation where only partial source profile data were available.The HERM results indicated significantly different seasonal source contributions to TVOCs in Xi’an.In particular,coal and biomass burning had contributions greater than half in winter(53.4%),whereas traffic sources were prevalent in summer(53.1%).This study’s results highlight the need for targeted and adjustable VOC control measures that account for seasonal differences in Xi’an;such measures should target not only the severe problem with VOC pollution but also the problem of consequent secondary pollution(e.g.,from ozone and secondary organic aerosols).
基金supported by the Special National Project on investigation of basic resources of China(Grant 2019FY101500)the National Natural Science Foundation of China(Grants 81861138003 and 31930001)supported an Australian Research Council(ARC)Australian Laureate Fellowship(FL170100022)。
文摘Healthcare workers(HCWs)are at high risk of occupational exposure to the new pandemic human coronavirus,SARSCoV-2,and are a source of nosocomial transmission in airborne infectious isolation rooms(AIIRs).Here,we performed comprehensive environmental contamination surveillance to evaluate the risk of viral transmission in AIIRs with 115 rooms in three buildings at the Shanghai Public Health Clinical Center,Shanghai,during the treatment of 334 patients infected with SARS-CoV-2.The results showed that the risk of airborne transmission of SARS-CoV-2 in AIIRs was low(1.62%,25/1544)due to the directional airflow and strong environmental hygiene procedures.However,we detected viral RNA on the surface of foot-operated openers and bathroom sinks in AIIRs(viral load:55.00–3154.50 copies/mL).This might be a source of contamination to connecting corridors and object surfaces through the footwear and gloves used by HCWs.The risk of infection was eliminated by the use of disposable footwear covers and the application of more effective environmental and personal hygiene measures.With the help of effective infection control procedures,none of 290 HCWs was infected when working in the AIIRs at this hospital.This study has provided information pertinent for infection control in AIIRs during the treatment of COVID-19 patients.
文摘The study evaluated the sources and controlling factors of the groundwater contaminants in an agroeconomic region of Lower Ganga Basin using principal component analysis(PCA),multivariable linear regressions(MLR),correlation analysis,and hierarchical cluster analysis,and evaluated the public health risks using the Latin Hypercube Sampling,goodness-of-fit statistics,Monte Carlo simulation and Sobol sensitivity analysis based on the 1000 samples collected in two sampling cycles(N=1000).The study reveals that the dissolution of fluoride-bearing minerals and semi-arid climate regulate the fluoride concentrations(0.10–18.25 mg/L)in groundwater.Extensive application of inorganic nitrogenous fertilizers and livestock manure mainly contributed to elevated nitrate levels(up to 435.0 mg/L)in groundwater.The health risks analysis indicates that fluoride exposure is more prevalent in the residents of each age group than the nitrate and both contaminants exhibited higher non-carcinogenic health risks on the infant and child(minor)age groups compared to adolescents and adults.Based on the cokriging interpolation mapping,the minor residents of 17.88%–23.15%of the total area(4545.0 km^(2))are vulnerable to methemoglobinemia whereas the residents of all age-groups in 38.47%–44.45%of the total area are susceptible to mild to severe dental/skeletal fluorosis owing to consumption of untreated nitrate and fluoride enriched groundwater.The Sobol sensitivity indices revealed contaminant levels,groundwater intake rate and their collective effects are the most influential factors to pose potential health risks on the residents.Artificial recharge and rainwater harvesting practices should be adopted to improve the groundwater quality and the residents are advised to drink purified groundwater.
基金Under the auspices of the key project of Shandong Provincial EnvironmentalProtectionBureau (No .2003447)
文摘Modern logistics is a new industry during the construction of national economy. Based on analyzing the environmental problem that was led by the limitation of the strategy during enacting the program of the modern logistics, SEA for modern logistics was implemented. In this paper, procedure and indicator system in the SEA are constructed, and Environmental Check List to identify environmental impact factors of SEA for modern logistics is established. And a conception that indicates friendly degree of logistics system with resources and environment, degree of green, is introduced. With the example of modern logistics program of Dalian in China, two methods are applied, AHP and Fuzzy Comprehensive Evaluation Method, in the implement of SEA for modern logistics development. It is concluded that degree of green of modern logistics in Dalian is high. However, several important factors should be paid much attention to in the SEA for modern logistics as well as in the formulation and implement of modern logistics in Dalian.
基金Supported by the National Science Foundation of China(Nos.32071573,41877544)the Science and Technology Service Network Initiative of Chinese Academy of Sciences(No.KFJ-STS-QYZD-2021-01-002)the Science and Technology Achievement Transformation Foundation of Inner Mongolia Autonomous Region(No.2021CG0013)。
文摘Cyanobacteria can accumulate as a heavy biomass on the leeward side of large eutrophic lakes,posing a potential threat to public health.The mitigating capacity of three flocculants and their potential impacts on the major environmental features of water and sediments was evaluated.Results indicate that polyaluminum chloride(PAC)and ferric chloride(FeCl)are efficient flocculants that can rapidly mitigate cyanobacterial blooms with chlorophyll-a concentrations higher tnan 1500 ug/L within 15 min.In comparison,cationic starch with chitosan could only treat cyanobacterial blooms in chlorophyll-a concentrations of less than 200μg/L.The addition of FeClcaused a decline in the pH value,while dissolved oxygen in the water column dropped to 2 mg/L during cationic starch with chitosan treatment for a high cyanobacterial biomass group.Thus,a combination of flocculants and oxygenators should be considered when treating high-concentration cyanobacterial blooms for emergency purposes.Additionally,the cell lysis of cyanobacteria caused by cationic starch with chitosan can result in an increase in total dissolved phosphorus and total dissolved nitrogen.Furthermore,the high accumlation of nutrients in sediments after the settling of cyanobacteria can cause high internal phosphorus pollution.The increase in the total organic carbon of the sediments can threaten lake restoration achieved by planting submerged macrophytes.
文摘In this study, salting-out assisted liquid-liquid extraction combined with high performance liquid chromatography diode array detector (SALLE-HPLC-DAD) method was developed and validated for simultaneous analysis of carbaryl, atrazine, propazine, chlorothalonil, dimethametryn and terbutryn in environmental water samples. Parameters affecting the extraction efficiency such as type and volume of extraction solvent, sample volume, salt type and amount, centrifugation speed and time, and sample pH were optimized. Under the optimum extraction conditions the method was linear over the range of 10 - 100 μg/L (carbaryl), 8 - 100 μg/L (atarzine), 7 - 100 μg/L (propazine) and 9 - 100 μg/L (chlorothalonil, terbutryn and dimethametryn) with correlation coefficients (R2) between 0.99 and 0.999. Limits of detection and quantification ranged from 2.0 to 2.8 μg/L and 6.7 to 9.5 μg/L, respectively. The extraction recoveries obtained for ground, lake and river waters were in a range of 75.5% to 106.6%, with the intra-day and inter-day relative standard deviation lower than 3.4% for all the target analytes. All of the target analytes were not detected in these samples. Therefore, the proposed SALLE-HPLC-DAD method is simple, rapid, cheap and environmentally friendly for the determination of the aforementioned herbicides, insecticide and fungicide residues in environmental water samples.
文摘The coronavirus disease 2019(COVID-19)pandemic,caused by the novel virus severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),began in December 2019 in China and has led to a global public health emergency.Previously,it was known as 2019-nCoV and caused disease mainly through respiratory pathways.The COVID-19 outbreak is ranked third globally as the most highly pathogenic disease of the twenty-first century,after the outbreak of SARS-CoV and Middle East respiratory syndrome in 2002 and 2012,respectively.Clinical,laboratory,and diagnostic methodology have been demonstrated in some observational studies.No systematic reviews on COVID-19 have been published regarding the integration of COVID-19 outbreaks(monitoring,fate and treatment)with environmental and human health perspectives.Accordingly,this review systematically addresses environmental aspects of COVID-19 outbreak such as the origin of SARS-CoV-2,epidemiological characteristics,diagnostic methodology,treatment options and technological advancement for the prevention of COVID-19 outbreaks.Finally,we integrate COVID-19 outbreaks(monitoring,fate and treatment)with environmental and human health perspectives.We believe that this review will help to understand the SARS-CoV-2 outbreak as a multipurpose document,not only for the scientific community but also for global citizens.Countries should adopt emergency preparedness such as prepare human resources,infrastructure and facilities to treat severe COVID-19 as the virus spreads rapidly globally.
文摘The present paper deals with the behavior of the Attached Microbial Community (AMC) for water self-purification at different riverbeds in a typical local river. The study quantitatively investigated the problem starting with in-situ sampling. It was found that more biomass of AMC was at riffles with wider distribution than in pools. High current velocity (HCV) plays a negative role at the initial stage of attachment on the riverbed, but HCV aids the community proliferation after stable attachment. External disturbances such as rainfalls and discharges from dams or reservoirs would detach the periphyton depending on the intensity of turbulence in water. However, it was discovered that the flock of periphyton could be restored very quickly because it was not completely removed. Thus, in order to enhance self-purification by periphyton, a suitable configuration of the riverbed must be constructed, and occasional appropriate repair along the channels would improve the decontamination of the river.
