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THE FLUX OF LAND-BASED SOURCE POLLUTANTS FROM TUMEN RIVER SYSTEM ENTERING THE SEA OF JAPAN
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作者 殷兴军 尹澄清 《Chinese Geographical Science》 SCIE CSCD 1998年第3期48-54,共0页
The influence of land based source pollutants to marine ecological environment is principally in coastal or enclosed sea waters. Flux of land based source pollutants into the sea will be effected due to social and ... The influence of land based source pollutants to marine ecological environment is principally in coastal or enclosed sea waters. Flux of land based source pollutants into the sea will be effected due to social and economic development in the Tumen River basin. Pollutant type and primary pollution factor of the Tumen River in Northeast China is described by weighted coefficient method in this paper. The results indicate that the river is organic pollution type and primary pollution factor is COD. Fresh water fraction proves that the estuary is not affected by tide cycle. COD annual flux entering the Sea of Japan calculated by zero dimension model in 1993 was 90.50 ×10 3 tons. It is estimated with emission coefficient method that the COD will be 176.4 ×10 3 and 458.6 ×10 3 tons for the years of 2000 and 2010 respectively. 展开更多
关键词 Tumen RIVER COD the SEA of JAPAN pollutION forecast land based SOURCE pollutants marine pollutION
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Pinus sylvestris and Picea abies canopy effects on deposition of air pollutants
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作者 ValentinasČerniauskas Iveta Varnagirytė‑Kabašinsk ienė +1 位作者 Valda Araminienė Vidas Stakėnas 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期34-46,共13页
Tree canopies influence atmospheric pollutant depositions depending on type,ecosystem characteristics,and local climatic conditions.This study investigated the impact of Pinus sylvestris L.and Picea abies(L.)H.Karst.,... Tree canopies influence atmospheric pollutant depositions depending on type,ecosystem characteristics,and local climatic conditions.This study investigated the impact of Pinus sylvestris L.and Picea abies(L.)H.Karst.,and a mixture of both,on the chemical composition of pre-cipitation.Three permanent plots within the ICP forest level Ⅱ monitoring network in Lithuania were selected to illustrate typical hemiboreal coniferous forests.The study analysed(1)the concentrations of NO_(2),NH_(3) and SO_(2) in the ambi-ent air;(2)the concentrations of SO_(4)^(2−),NO_(3)^(−),NH_(4)^(+),Na^(+),K^(+),Ca^(2+) and Cl^(-) in throughfall beneath canopies and in precipitation collected in an adjacent field,and(3)S and total N,Na^(+),K^(+),Ca^(2+)and Cl−depositions in throughfall and precipitation over 2006-2022.Results show a signifi-cant decrease in SO_(2) emissions in the ambient air;NO_(2) and NH_(3) emissions also decreased.The canopies reduced the acidity of throughfall,although they led to notably higher concentrations of SO_(4)^(2−),NO_(3)^(−),Na^(+),and particularly K^(+).During the study,low variability in NO_(3)^(-)deposition and a decrease in NH_(4)^(+)deposition occurred.Deposition loads increased by 20-30%when precipitation passed through the canopy.The cumulative deposition of S,Cl,Na,K,Ca,and N was greater under P.abies than under P.sylvestris.How-ever,K deposition in throughfall was considerably lower under P.sylvestris compared to the P.abies or mixed stand.Throughfall S depositions declined across all three coniferous plots.Overall,there was no specific effect of tree species on throughfall chemistry. 展开更多
关键词 PRECIPITATION THROUGHFALL Deposition of chemicals pollutION Lithuania
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Unsustainable Land-Based Source Pollution in a Climate of Change: A Roadblock to the Conservation and Recovery of Elkhorn Coral <i>Acropora palmata</i>(Lamarck 1816) 被引量:1
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作者 Geraldine Díaz-Ortega Edwin A. Hernández-Delgado 《Natural Resources》 2014年第10期561-581,共21页
Chronic eutrophication and turbidity are critical detrimental factors impacting coral reef ecosystems, adversely affecting their ecological functions, services, benefits, and resilience across multiple spatial scales ... Chronic eutrophication and turbidity are critical detrimental factors impacting coral reef ecosystems, adversely affecting their ecological functions, services, benefits, and resilience across multiple spatial scales and over prolonged periods of time. Inadequate land use practices and lack of appropriate sewage treatment can adversely contribute to increase land-based source pollution (LBSP) impacts in coastal waters and to magnify impacts by sea surface warming trends associated to climate change. Fringing coral reefs off Vega Baja, Puerto Rico, support extensive remnant patches of Elkhorn coral Acropora palmata (Lamarck 1816), which was listed in 2006 as a threatened species under the US Endangered Species Act. Chronic impacts by LBSP have significantly affected local downstream fringing reefs. We characterized the spatial extent of a water quality stress gradient across 12 reefs along the Vega Baja coast through monthly measurements of multiple physico-chemical parameters. Most parameters, particularly PO4, , chlorophyll-a, and the concentration of optical brighteners (OABs), showed a statistically significant increase (PERMANOVA, p < 0.05) in waters close to the main pollution sources, but also in waters adjacent to Cibuco River effluents. Dissolved oxygen also declined and turbidity increased on polluted sites. PO4, , and chlorophyll-a, exceeded recommended concentrations for coral reef ecosystems by factors of 7 - 50 times, 600 - 1240 times, and 17 - 83 times, respectively, depending on the source of the effluents and the distance from sewage pollution sources. Also, water turbidity exceeded 4 - 10 times the recommended value for pristine coral reefs. Coral reefs showed significant decline in close proximity to the polluted zone, showing a significantly different benthic community structure (PERMANOVA, p < 0.0001) dominated by non-reef building taxa (i.e., macroalgae, algal turf) and bare substrate. Percent coral cover and abundance of A. palmata, showed a significant increase with distance. Coral species richness, species diversity index, and the variance in taxonomic distinctness were very low on reef patches adjacent to the polluted zone, increased at a moderate distance with increasing coral cover and co-existence of multiple species, and declined far from the pollution source due to dominance exerted by A. palmata. This study suggests that chronic LBSP resulted in a major decline of one of the largest and most dense remnant stands of A. palmata across the northeastern Caribbean and that nutrient and chlorophyll-a concentrations were unsustainable for coral reefs. This situation requires immediate solution to prevent further damage to these unprecedented resources. It further suggests that chronic LBSP may synergistically magnify sea-surface warming impacts driving corals to an increased state of risk in face of forecasted climate change impacts. Actions to mitigate and adapt to climate change impacts on coral reefs must require a priori controls of LBSP to be effective. 展开更多
关键词 ACROPORA palmata CORAL REEF Decline Eutrophication land-based Source pollution
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Hydrodynamic Cavitation Enhanced SR-Aops Degradation of Organic Pollutants in Water:A Review
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作者 Xiufeng Zhu Jingying Wang 《Fluid Dynamics & Materials Processing》 EI 2024年第4期671-692,共22页
SR-AOP(sulfate radical advanced oxidation process)is a novel water treatment method able to eliminate refractory organic pollutants.Hydrodynamic cavitation(HC)is a novel green technology,that can effectively produce s... SR-AOP(sulfate radical advanced oxidation process)is a novel water treatment method able to eliminate refractory organic pollutants.Hydrodynamic cavitation(HC)is a novel green technology,that can effectively produce strong oxidizing sulfate radicals.This paper presents a comprehensive review of the research advancements in these fields and a critical discussion of the principal factors influencing HC-enhanced SR-AOP and the mechanisms of synergistic degradation.Furthermore,some insights into the industrial application of HC/PS are also provided.Current research shows that this technology is feasible at the laboratory stage,but its application on larger scales requires further understanding and exploration.In this review,some attention is also paid to the design of the hydrodynamic cavitation reactor and the related operating parameters. 展开更多
关键词 Hydrodynamic cavitation organic pollutant PERSULFATE DEGRADATION influence factor
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Bivariate Analysis of Pollutants Monthly Maxima in Mexico City Using Extreme Value Distributions and Copula
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作者 Juan A. Vazquez-Morales Eliane R. Rodrigues Hortensia J. Reyes-Cervantes 《Journal of Environmental Protection》 2024年第7期796-826,共31页
In the present work, we are interested in studying the joint distributions of pairs of the monthly maxima of the pollutants used by the environmental authorities in Mexico City to classify the air quality in the metro... In the present work, we are interested in studying the joint distributions of pairs of the monthly maxima of the pollutants used by the environmental authorities in Mexico City to classify the air quality in the metropolitan area. In order to obtain the joint distributions a copula will be considered. Since we are analyzing the monthly maxima, the extreme value distributions of Weibull and Fréchet are taken into account. Using these two distributions as marginal distributions in the copula a Bayesian inference was made in order to estimate the parameters of both distributions and also the association parameters appearing in the copula model. The pollutants taken into account are ozone, nitrogen dioxide, sulphur dioxide, carbon monoxide, and particulate matter with diameters smaller than 10 and 2.5 microns obtained from the Mexico City monitoring network. The estimation was performed by taking samples of the parameters generated through a Markov chain Monte Carlo algorithm implemented using the software OpenBugs. Once the algorithm is implemented it is applied to the pairs of pollutants where one of the coordinates of the pair is ozone and the other varies on the set of the remaining pollutants. Depending on the pollutant and the region where they were collected, different results were obtained. Hence, in some cases we have that the best model is that where we have a Fréchet distribution as the marginal distribution for the measurements of both pollutants and in others the most suitable model is the one assuming a Fréchet for ozone and a Weibull for the other pollutant. Results show that, in the present case, the estimated association parameter is a good representation to the correlation parameters between the pair of pollutants analyzed. Additionally, it is a straightforward task to obtain these correlation parameters from the corresponding association parameters. 展开更多
关键词 COPULA Extreme Value Distribution Bayesian Inference Air pollution Mexico City
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Spatial Distribution Assessment and Source Apportionment of Land-Based Pollutant Yield from Qingdao, China
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作者 SU Ying LIANG Shengkang +1 位作者 ZHANG Peng WANG Xiulin 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第1期151-158,共8页
The spatial distribution of chemical oxygen demand(COD) and total nitrogen(TN) yield from Qingdao are studied by comparing pollutant yield amount, densities and spatial aggregation(Getis-Ord indexes) among the land-ba... The spatial distribution of chemical oxygen demand(COD) and total nitrogen(TN) yield from Qingdao are studied by comparing pollutant yield amount, densities and spatial aggregation(Getis-Ord indexes) among the land-based pollutant source regions(PSRs) entering the three sub-seas(i.e. the Jiaozhou Bay(JZB), other coastal area in the Yellow Sea(OCAYS) and Laizhou Bay(LZB), respectively). Industrial composition of the loads are also studied by comparing pollutant yield among the sources of agriculture, rural domesticity, industry, urban domesticity and service, and calculation of Gini coefficient. Results show that spatial distribution of COD and TN yield from Qingdao are extremely unbalanced. The JZB, with less than 3% of the total coastal sea area of Qingdao, received 62% COD load and 65% TN yield from Qingdao, while the OCAYS, with more than 97% area, only received 23% COD and 20% TN, which consist with the much worsen water quality of JZB than that of OCAYS. On the other hand, the source apportionment of COD and TN loads in the PSRs entering JZB and the OCAYS was similar. The agricultural and domestic sources with high pollution intensity account for more than 80%, while the industrial and service sources with low pollution intensity account for less than 20%. While Gini coefficients, COD 0.81 and TN 0.84 which are much higher than the ‘imbalance' threshold of 0.4, show the uneven industrial structure of Qingdao. These results may be useful in the determination of land-based pollution total amount control at the PSR level. 展开更多
关键词 Qingdao land-based pollutANT pollutANT YIELD pollutION INTENSITY industrial structure
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Impact of Air Pollutants on Lung Function and Inflammatory Response in Asthma in Shanghai
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作者 Guifang Wang Youzhi Zhang +6 位作者 Haiyan Yang Yi Yang Liang Dong Peng Zhang Jie Liu Xiaodong Chen Yi Gong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第8期811-822,共12页
Objective Air pollution is a leading public health issue.This study investigated the effect of air quality and pollutants on pulmonary function and inflammation in patients with asthma in Shanghai.Methods The study mo... Objective Air pollution is a leading public health issue.This study investigated the effect of air quality and pollutants on pulmonary function and inflammation in patients with asthma in Shanghai.Methods The study monitored 27 asthma outpatients for a year,collecting data on weather,patient self-management[daily asthma diary,peak expiratory flow(PEF)monitoring,medication usage],spirometry and serum markers.To explore the potential mechanisms of any effects,asthmatic mice induced by ovalbumin(OVA)were exposed to PM_(2.5).Results Statistical and correlational analyses revealed that air pollutants have both acute and chronic effects on asthma.Acute exposure showed a correlation between PEF and levels of ozone(O_(3))and nitrogen dioxide(NO_(2)).Chronic exposure indicated that interleukin-5(IL-5)and interleukin-13(IL-13)levels correlated with PM_(2.5)and PM_(10)concentrations.In asthmatic mouse models,exposure to PM_(2.5)increased cytokine levels and worsened lung function.Additionally,PM_(2.5)exposure inhibited cell proliferation by blocking the NF-κB and ERK phosphorylation pathways.Conclusion Ambient air pollutants exacerbate asthma by worsening lung function and enhancing Th2-mediated inflammation.Specifically,PM_(2.5)significantly contributes to these adverse effects.Further research is needed to elucidate the mechanisms by which PM_(2.5)impacts asthma. 展开更多
关键词 Ambient air pollutants Acute and chronic effects on asthma PM_(2.5) OVA-induced asthmatic mice
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Response of warm season secondary pollutants to emissions and meteorology in the North China Plain region during 2018-2022
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作者 Yueqi Gao Siyu Wang +7 位作者 Zhaolei Zhang Wenxuan Yu Shuai Wang Shengqiang Zhu Peng Wang Yan Li Yele Sun Hongliang Zhang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第4期58-64,共7页
自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_... 自2013年起中国空气质量虽改善,但华北平原(NCP)重污染仍存在且二次污染加剧,而人们对其成因和变化了解有限.本研究利用2018-2022年数据,借助CMAQ模型探讨此污染响应.结果显示,在2018-2022年间,PM_(2.5)浓度显著下降31%-37%,O_(3)和NO_(2)的年下降速率分别为1%和0.5%SIA和SOA也显著减少,每年分别减少9%和6%PM_(2.5)主要因排放减少而下降,而O_(3)则受气象影响而波动.硫酸盐和铵下降的主因是减排,而硝酸盐对气象变化敏感排放和气象变化对SOA的总体减少同样重要,但人为SOA对排放控制敏感生物SOA易受气象变化影响.研究强调了控制人为排放对缓解NCP地区夏季二次污染的重要性. 展开更多
关键词 PM_(2.5) 二次污染物 人为排放 气象 华北平原
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Absorption capacity of major urban afforestation species in north-eastern China to heavy metal pollutants in the atmosphere 被引量:10
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作者 穆立蔷 孙海燕 祝宁 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期73-76,J003-J004,共6页
Totally 24 arbor tree species and 6 shrub species were measured on their absorption capacities to heavy metal Pb, Cd, Cr, and Hg by collecting and analyzing the leaves of trees along different streets in Harbin city i... Totally 24 arbor tree species and 6 shrub species were measured on their absorption capacities to heavy metal Pb, Cd, Cr, and Hg by collecting and analyzing the leaves of trees along different streets in Harbin city in Sept. to Oct. of 2003. The results showed that all the measured species had certain absorbency to the pollutants (Pb, Cd, Cr and Hg), but there existed significant difference in absorption capacity for different species to different pollutants. The measured tree species were classified into three categories by their absorption quantum of heavy metal pollutants. Among the species measured,Betula platyphylla, Ulmus pumila var.pendula, andPrunus persicaf.rubro-plena had high capacity in absorbing Pb;Populus xiahei, P. nigra var.Italica, P. alba x P. berolinensis andSalix matsudana had had high capacity in absorbing Cd;Phellodendron amurense, Syringa oblata, Salix matsudana, Pinus tabulaeformis var.mukdensis, Picea koraiensis, Prunus persica f.rubro-plena, P. triloba andAcer negundo, etc. had high capacity in absorption of Cr;Prunus triloba, Quercus mongolica, Salix matsudana, Sambucus williamsii, Pyrus ussuuriensis andSpiraea fritschiana were good at absorption of Hg. This study might offer scientific foundation for selection of urban afforestation species in different polluted conditions caused by heavy metals. Keywords Greening tree species - Heavy metal - Pollutants - Plumbum - Cadmium - Chromium - Mercury - Absorptivity CLC number S731.2 - X501 Document code A Foundation item: This study is financially supported by the Special Programme for Agriculture under Ministry of Chinese Science and Technology (No. 2002BA516A15-01).Biography: MU Li-qiang (1966-), female, Associate professor in Northeast Forestry University, Harbin 150040, P. R. China.Responsible editor: Zhu Hong 展开更多
关键词 Greening tree species Heavy metal pollutants Plumbum CADMIUM CHROMIUM MERCURY ABSORPTIVITY
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Effects of Heavy Metal and Pollutants on the Non-special Immunity of the Shrimp and Crab
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作者 艾春香 王晓娟 +2 位作者 李少菁 王桂忠 林琼武 《Marine Science Bulletin》 CAS 2008年第1期54-63,共10页
This paper attempted to review and evaluate existing information about the effects of heavy metal, ammonia-N, nitrite and the organic pollutants on the non-special immune response of the shrimp and crab, which providi... This paper attempted to review and evaluate existing information about the effects of heavy metal, ammonia-N, nitrite and the organic pollutants on the non-special immune response of the shrimp and crab, which providing theory for improving the self-immunity of shrimp and crab by meliorating cultural environment. In addition, it could provide information for further study on this field. 展开更多
关键词 Shrimp and crab non-special immune heavy metal pollutants
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A Study of the Relationship between Air Pollutants and Inversion in the ABL over the City of Lanzhou 被引量:14
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作者 张强 李宏宇 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第4期879-886,共8页
By analyzing the pollutant concentrations over the urban area and over the rural area of the city of Lanzhou, Gansu Province, China, the relationships between the daytime inversion intensity and the pollutant concentr... By analyzing the pollutant concentrations over the urban area and over the rural area of the city of Lanzhou, Gansu Province, China, the relationships between the daytime inversion intensity and the pollutant concentration in the atmospheric boundary layer (ABL) are studied with the consideration of wind speed and direction, potential temperature, specific humidity profiles, pollutant concentration in the ABL, the surface temperature, and global radiation on the ground. It was shown that the daytime inversion is a key factor in controlling air pollution concentration. A clear and positive feedback process between the daytime inversion intensity and the air pollutants over the city was found through the analysis of influences of climatic and environmental factors. The mechanisms by which the terrain and air pollutants affect the formation of the daytime inversion are discussed. The solar radiation as the essential energy source to maintain the inversion is analyzed, as are various out-forcing factors affecting the inversion and air pollutants. At last, a physical frame of relationships of air pollution with daytime inversion and the local and out-forcing factors over Lanzhou is built. 展开更多
关键词 relationship Lanzhou City INVERSION pollutANT out-forcing factors
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Uptake and translocation of organic pollutants in plants:A review 被引量:10
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作者 ZHANG Cheng FENG Yao +3 位作者 LIU Yuan-wang CHANG Hui-qing LI Zhao-jun XUE Jian-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第8期1659-1668,共10页
Organic pollutants, such as polychlorinated dJbenzo-p-dioxins and polychlofinated dibenzofurans (PCDD/Fs), polychlodnated biphenyls (PCBs), antibiotics, herbicides, and bisphenol A (BPA), are commonly found in a... Organic pollutants, such as polychlorinated dJbenzo-p-dioxins and polychlofinated dibenzofurans (PCDD/Fs), polychlodnated biphenyls (PCBs), antibiotics, herbicides, and bisphenol A (BPA), are commonly found in agricultural environments. They are released into the environment as a result of their use for human health purposes and farm management activities, and are often discharged as waste-water effluents. Most of these organic pollutants are taken up by plants through roots and leaves, and when they enter the tissue, they cause serious damage to the plants. Although the toxicity of organic pollutants to plants, especially to plant cells, has been intensively studied, a systematic review of these studies is lacking. Here we review researches on the toxicity of organic pollutants, their uptake, and translocation in plants. Our objective is to assemble existing knowledge concerning the interaction of organic pollutants with plants, which should be useful for the development of plant-based systems for removing pollutants from aquatic and agricultural environments. 展开更多
关键词 organic pollutants PLANT UPTAKE CYTOTOXICITY
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Principal Component Analysis of Major Pollutants Discharge Amount in Major Cities 被引量:1
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作者 于淼 金童 《Agricultural Science & Technology》 CAS 2017年第7期1260-1262,共3页
With the development of industry in China, the emission issues of indus- trial wastewater has got more and more attention. Excessive levels of pollutants in wastewater are urgent problem to be solved. Together with th... With the development of industry in China, the emission issues of indus- trial wastewater has got more and more attention. Excessive levels of pollutants in wastewater are urgent problem to be solved. Together with the emissions of do- mestic wastewater, the discharge amount of pollutants has exceeded standard in many cities, which not only pollutes the water resources, but also greatly threatens the environment, and does great harm to people's health. The principal component analysis was conducted based on the principal components extracted from the data of major pollutants emission conditions in the wastewater of major cities from the China Statistical Yearbook 2014. 展开更多
关键词 Principal component analysis pollutant discharge amount Industrial wastewater: Domestic wastewater
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A simulation analysis of the migration and transformation of pollutants contained in landfill leachate 被引量:4
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作者 WANGHong-qi TIANKai-ming +2 位作者 QIYong-qiang CHENJia-jun WANGYa-nan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第6期827-835,共9页
A dynamic composite model for a soil-water system that can be used to simulate the movement of leachate from a landfill. The composite model includes nine sub-models that trace water movement and the migration and tra... A dynamic composite model for a soil-water system that can be used to simulate the movement of leachate from a landfill. The composite model includes nine sub-models that trace water movement and the migration and transformation of five pollutants(organic N, NH - 4, NO - 3, NO - 2, and Cl -) in saturated and unsaturated soil. The model to simulate the movement of leachate from a landfill in Laogang Town, Shanghai City was used. In this application, the values for the model parameters were obtained by performing a laboratory simulation experiment of water movement and pollutant migration and transformation in soil columns. Soil and leachate obtained from the landfill site and its vicinity were used in the laboratory experiments. The model was then used to simulate leachate movement and pollutant activity during the ten-year period when the landfill was in operation and in the twenty-year period following its closure. The simulation results revealed that the leachate migrated into the groundwater at the rate of 90—100 meters per year. This model can be applied in the design of future landfills in China for the purpose of assessing and forecasting leachate plumes. 展开更多
关键词 simulation LEACHATE LANDFILL pollutant migration pollutant transformation mathematical model
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Statistical Distributions of Ambient Air Pollutants in Shanghai, China 被引量:11
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作者 HAI-DONGKAN BING-HENGCHEN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第3期366-372,共7页
Objective To determine the best statistical distribution of concentration data of major air pollutants in Shanghai. Methods Four types of theoretic distributions (lognormal, gamma, Pearson V and extreme value) were... Objective To determine the best statistical distribution of concentration data of major air pollutants in Shanghai. Methods Four types of theoretic distributions (lognormal, gamma, Pearson V and extreme value) were chosen to fit daily average concentration data of PM10, SO2 and NO2 from June 1, 2000 to May 31, 2003 in Shanghai by using the maximum likelihood method. The fit results were evaluated by Chi-square test. Results The best-fit distributions for PM10,SO2 and NO2 concentrations in Shanghai were lognormal, Pearson V, and extreme value distributions, respectively. Conclusion The results can be further applied to local air pollution prediction and control, e.g., the probabilities exceeding the air quality standard and emission source reduction of air pollutant concentration to meet the standard. 展开更多
关键词 Air pollution Statistical distribution SHANGHAI Maximum likelihood.
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Spatiotemporal Variations and Regional Transport of Air Pollutants in Two Urban Agglomerations in Northeast China Plain 被引量:10
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作者 LI Xiaolan HU Xiaoming +3 位作者 SHI Shuaiyi SHEN Lidu LUAN Lan MA Yanjun 《Chinese Geographical Science》 SCIE CSCD 2019年第6期917-933,共17页
Characteristics of air pollution in Northeast China(NEC) received less research attention in the past comparing to other heavily polluted regions in China.Spatiotemporal variations of six criteria air pollutants(PM10,... Characteristics of air pollution in Northeast China(NEC) received less research attention in the past comparing to other heavily polluted regions in China.Spatiotemporal variations of six criteria air pollutants(PM10, PM2.5, SO2, NO2, O3 and CO) in Central Liaoning Urban Agglomeration(CLUA) and Harbin-Changchun Urban Agglomeration(HCUA) in NEC Plain were analyzed in this study based on three-year hourly observations of air pollutants and meteorological variables from 2015 to 2017.The results indicated that the annual mean concentrations of air pollutants are generally higher in the middle and southern regions in NEC Plain and lower in the northern region.Megacities such as Shenyang, Harbin and Changchun experience severe air pollution, with a three-year averaged air quality index(AQI) larger than 80, far exceeding the daily AQI standard at the first-level of 50 in China.The annual mean PM and SO2 concentrations decrease most significantly in NEC urban agglomerations from 2015 to 2017, followed by CO and NO2, while O3 shows a slight increasing trend.All the six pollutants exhibit obvious seasonal and diurnal variations, and these variations are dictated by local emission and meteorological conditions.PM2.5 and O3 concentrations in NEC urban agglomerations strongly depend on wind conditions.High O3 concentrations at different cities usually occur in presence of strong winds but are independent on wind direction(WD), while high PM2.5 is usually accompanied by weak winds and poor dispersion condition, and sometimes also occur when the northerly or southerly winds are strong.Regional transport of air pollutants between NEC urban agglomerations is common.A severe haze event on November 1–4, 2017 is examined to demonstrate the role of regional transport on pollution. 展开更多
关键词 criteria air pollutANT METEOROLOGICAL condition regional transport urban AGGLOMERATION of NORTHEAST China
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Experiments and numerical simulations on transport of dissolved pollutants around spur dike 被引量:8
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作者 Li-ping CHEN Jun-cheng JIANG 《Water Science and Engineering》 EI CAS 2010年第3期341-353,共13页
The flow field around a spur dike has three-dimensional characteristics. In order to analyze the influence of the flow field on pollutant transport, based on a compressive volume of fluid (VOF) scheme, the three-dim... The flow field around a spur dike has three-dimensional characteristics. In order to analyze the influence of the flow field on pollutant transport, based on a compressive volume of fluid (VOF) scheme, the three-dimensional transient compressive pollutant transport model (CPTM) and the cubic equation (CE) bounded differencing scheme were developed. For the calibration and validation of CPTM, laboratory experiments were carried out in a flume with a non-submerged spur dike. The spur dike was angled at 60°, 90°, and 120° from the upstream direction. The simulation results agreed with the experimental results. The simulations and experiments showed that the distribution of pollutant concentration was determined by circumfluence and the main flow. Concentration decay in the circumfluenee zone was slower than that in the main flow. Downstream of the spur dike, the concentration fluctuation became intensive with the increase of spur dike angle. 展开更多
关键词 VOF spur dike dissolved pollutant numerical simulation experiment
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Organobentonites as adsorbents for some organic pollutants and its application in wastewater treatment 被引量:5
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作者 Zhu Lizhong Zhang Jianying +2 位作者 Li Yimin Shen Xueyou Qi Wenbin(Department of Environmental Science. Hangzhou University, Hangzhou 310028, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第3期378-383,共6页
Two organobentonites were synthesized by placing quaternary ammonium cationscetyltrimethylammonium bromide (CTMAB) and cetylpyridinium chloride (CPC) on bentonite bycation exchange. Their ability to adsorb phenol, ani... Two organobentonites were synthesized by placing quaternary ammonium cationscetyltrimethylammonium bromide (CTMAB) and cetylpyridinium chloride (CPC) on bentonite bycation exchange. Their ability to adsorb phenol, aniline. nitrobenzene and p-nitrophenol were examined.The optimal conditions for organobentonites to remove the organic pollutants from waterwere studied. The removal rates for organobentonites to treat the organic compounds in water werefound to be over 8 times for the original mineral (untreated bentonite).The removal rates of organic pollutants and COD of wastewater were further improved by organobentonites in the presence of aluminum sulfate. The structure of organobentonites and the mechanism for their adsorption were investigated by X-ray diffraction (XRD) analysis, infrared spectra and BET surface area. 展开更多
关键词 organobentonites adsorbents organic pollutants wastewater treatment.
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Removal of Nitrogen, Phosphorus, and Organic Pollutants From Water Using Seeding Type Immobilized Microorganisms 被引量:6
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作者 LIN WANG LI-JING HUANG LUO-JIA YUN FEI TANG JING-HUI ZHAO YAN-QUN LIU XIN ZENG QI-FANG LUO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2008年第2期150-156,共7页
Objective To study the possibility of removing nitrogen, phosphorus, and organic pollutants using seeding type immobilized microorganisms. Methods Lakes P and M in Wuhan were chosen as the objects to study the removal... Objective To study the possibility of removing nitrogen, phosphorus, and organic pollutants using seeding type immobilized microorganisms. Methods Lakes P and M in Wuhan were chosen as the objects to study the removal of nitrogen, phosphorus, and organic pollutants with the seeding type immobilized microorganisms. Correlations between the quantity of heterotrophic bacteria and the total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) in the two lakes were studied. The dominant bacteria were detected, inoculated to the sludge and acclimated by increasing nitrogen, phosphorus and decreasing carbon source in an intermittent, time-controlled and fixed-quantity way. The bacteria were then used to prepare the seeding type immobilized microorganisms, selecting diatomite as the adsorbent cartier. The ability and influence factors of removing nitrogen, phosphorus, and organic pollutant from water samples by the seeding type immobilized microorganisms were studied. Results The coefficients of the heterotrophic bacterial quantity correlated with TOC, TP, and TN were 0.9143, 0.8229, 0.7954 in Lake P and 0.9168, 0.7187, 0.6022 in Lake M. Ten strains of dominant heterotrophic bacteria belonging to Pseudomonas, Coccus, Aeromonas, Bacillus, and Enterobateriaceae, separately, were isolated. The appropriate conditions for the seeding type immobilized microorgansims in purifying the water sample were exposure time=24 h, pH=7.0-8.0, and quantity of the immobilized microorganisms=0.75-1g/50 mL. The removal rates of TOC, TP, and TN under the above conditions were 80.2%, 81.6%, and 86.8%, respectively. Conclusion The amount of heterotrophic bacteria in the two lakes was correlated with TOC, TP, and TN. These bacteria could be acclimatized and prepared for the immobilized microorganisms which could effectively remove nitrogen, phosphorus, and mixed organic pollutants in the water sample. 展开更多
关键词 Heterotrophic bacteria ACCLIMATION Immobilized microorganisms NITROGEN PHOSPHORUS Mixed organic pollutants
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Carbonaceous Nanofibers-titanium Dioxide Nanocomposites: Synthesis and Use as a Platform for Removal of Dye Pollutants 被引量:3
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作者 郭洪影 JIANG Shan +7 位作者 WANG Chaoyuan LI Shenwan FENG Jianjian 孙红梅 ZHU Hongda GUO Huiling LIU Mingxing SUN Honghao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第2期303-307,共5页
A mild chemistry route was developed to prepare carbonaceous nanofibers-titanium dioxide(CNF-TiO_2) nanocomposites for removal of dye pollutants. In the process of the template-directed hydrothermal carbonization(HTC)... A mild chemistry route was developed to prepare carbonaceous nanofibers-titanium dioxide(CNF-TiO_2) nanocomposites for removal of dye pollutants. In the process of the template-directed hydrothermal carbonization(HTC), ultrathin Te nanowires were adopted as templates and glucose as the carbon source, and TiO_2 was decorated on CNF via the hydrolysis of tetrabutyltitanate in the presence of CNF in ethanol. The as-prepared materials were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), energy-dispersive X-ray(EDX) and X-ray diffraction(XRD). SEM and TEM observations displayed that TiO_2 nanoparticles were anchored on the CNF. EDX and XRD data confirmed that the assynthesized samples were CNF-TiO_2, and TiO_2 belonged to anatase titania. Taking advantage of combined benefits of carbonaceous nanofibers and titanium dioxide, these CNF-TiO_2 nanocomposites exhibited higher removal efficiency in a short time and showed good reusability. It was showed that over 97% of Rhodamine B could be removed in 15 min without generating the solid and liquid wastes. The removal efficiency of dyes was still over 80% after reuse in five cycles. All the results demonstrate that the as-prepared CNF-TiO_2 composites are effective materials for fast and effective removal of dye pollutants and thus can provide a new platform for dye decontamination. 展开更多
关键词 carbon materials NANOCOMPOSITES DYE pollutants
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