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The Application of Regional Coordinate in the Relatively Heavily Polluted Area of Chromium in Water of the Hun River, Northeast China
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作者 Kan Zhang Xue Feng 《Journal of Geoscience and Environment Protection》 2023年第9期233-241,共9页
The aim of the present investigation was to research the relatively heavily polluted area of chromium in water of the Hun River. According to variance analysis, the concentrations of chromium in water showed significa... The aim of the present investigation was to research the relatively heavily polluted area of chromium in water of the Hun River. According to variance analysis, the concentrations of chromium in water showed significant differences at different sampling stations. In addition, we obtained the static concentration function of chromium in water by using a curve-fitting tool and the measured data. It was clear that the static concentration function perfectly revealed the change in regulations between the concentration of chromium in water and spatial coordinates. We furthermore determined the relatively heavily polluted area of chromium in water by using a regional coordinate formula. The results indicated that the relatively heavily polluted area of chromium in water was from H1 to H2, which was highly consistent with the measured data. It is clear that the determination of the relatively heavily polluted area of chromium is helpful to the comprehensive treatment of chromium pollution. The static concentration function and the regional coordinate of the relatively heavily polluted area of chromium in water comprehensively describe the distribution characteristics of chromium in water, which provide a scientific basis for water environment improvement and risk management in the Hun River. 展开更多
关键词 Heavy Metal Pollution Mathematical Model Risk Evaluation
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Generation of a Controlled Polluted Atmosphere for Vehicles’ Cabins Air Quality Characterization
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作者 N.M.Hafs A.Mehel +2 位作者 G.Fokoua P.Chevrier H.Er-Rbib 《Journal of Mechanics Engineering and Automation》 2023年第2期17-31,共15页
Air pollution induces significant health risks to individuals exposed to high levels of pollutants concentration. For ground vehicles, pollutants infiltrate the car cabin through the ventilation system, leading to pot... Air pollution induces significant health risks to individuals exposed to high levels of pollutants concentration. For ground vehicles, pollutants infiltrate the car cabin through the ventilation system, leading to potential health issues. To address this problem, a project was undertaken to develop a protocol for characterizing in-cabin air quality. The study involved a closed chamber (the bubble) where its internal multiphase flow has been optimized to create controlled polluted atmospheres. Experiments were conducted to optimize the positioning of the stirring fan and particle generation source, ensuring a homogeneous distribution of fine and ultrafine particles. This study demonstrated the feasibility of implementing a platform dedicated to characterizing the vehicles’ in-cabin air quality under controlled conditions. It allows a better understanding of the dynamics of particle infiltration and the establishment of an optimized protocol for simultaneous measurements of indoor and outdoor concentrations. 展开更多
关键词 Air pollution chamber vehicle interior air quality car cabin particle infiltration
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Clean-up and disposal process of polluted sediments from urban rivers 被引量:5
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作者 HE Pin-jing SHAO Li-ming +2 位作者 GU Guo-wei BIAN Cheng-lin XU Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第4期435-438,共4页
In this paper, the discussion is concentrated on the properties of the polluted sediments and the combination of clean up and disposal process for the upper layer heavily polluted sediments with good flowability. Base... In this paper, the discussion is concentrated on the properties of the polluted sediments and the combination of clean up and disposal process for the upper layer heavily polluted sediments with good flowability. Based on the systematic analyses of various clean up processes, a suitable engineering process has been evaluated and recommended. The process has been applied to the river reclamation in Yangpu District of Shanghai City, China. An improved centrifuge is used for dewatering the dredged sludge, which plays an important role in the combination of clean up and disposal process. The assessment of the engineering process shows its environmental and technical economy feasibility, which is much better than that of traditional dredging disposal processes. 展开更多
关键词 urban RIVERS polluted SEDIMENTS clean up DISPOSAL DREDGING DEWATERING feasibility analysis
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Application of a Stereo Constructed Wetland Mode to the Treatment of Slightly Polluted Source Water 被引量:7
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作者 CHEN Yu-quan ZUO Zhuo GUO Xiao 《Meteorological and Environmental Research》 CAS 2012年第12期63-67,共5页
[Objective] The study aimed to discuss the application of a stereo constructed wetland to the treatment of slightly polluted source water. [Method] In this study, a new stereo constructed wetland mode was put forward,... [Objective] The study aimed to discuss the application of a stereo constructed wetland to the treatment of slightly polluted source water. [Method] In this study, a new stereo constructed wetland mode was put forward, and a pilot project of water ecological purification in Xinsheng River, the diversion channel of Shijiuyang Waterwork in Jiaxing City, were analyzed. Afterwards, the impact factors of water purification by the technology were discussed from water quality and quantity, season and climate, species configuration, management and maintenance. [Result] Under three different hydraulic loading conditions, the pilot project effectively improved water SD and DO level, and reduced SS, CODCr, NH3-N, TN and TP significantly in summer and autumn, so that effluent water quality reached surface water standard at Grade III. [Conclusion] The stereo constructed wetland mode composed of constructed wetland and underwater forest used to treat slightly polluted source water is feasible and has a good promotion prospect. 展开更多
关键词 Ecological purification Slightly polluted WATER WATER source area UNDERWATER forest CONSTRUCTED WETLAND China
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Review of Ecological Floating Bed Restoration in Polluted Water 被引量:2
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作者 Yu Deng Fuquan Ni 《Journal of Water Resource and Protection》 2013年第12期1203-1209,共7页
Using Ecological Floating Bed (EFB) to purify polluted water is a process of ecological restoration at virgin position, as well as a complicated physical, chemical and biological process. Its core is utilizing aquatic... Using Ecological Floating Bed (EFB) to purify polluted water is a process of ecological restoration at virgin position, as well as a complicated physical, chemical and biological process. Its core is utilizing aquatic plants and root’s microbes to absorb nitrogen and phosphorus elements, degrade organic matter and enrich heavy metal. EFB has been applied to some water pollution control projects at home and abroad, and has got several achievements. However, there are some factors influenced the removal rate of pollutants, including plants, temperature, seasons, processing time, coverage and initial concentration of pollutants. In the future, the development orientation has been prospected from plant and its combinations, the transformation of EFB structure and the utilization of aquatic resources, and probed the technology of EFB’s building and management, to implement the win-win of landscape benefit and ecological function. 展开更多
关键词 ECOLOGICAL FLOATING BED polluted Water AQUATIC Plants PURIFICATION
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SUSTAINABLE DEVELOPMENT OF THE SERIOUSLY POLLUTED CITIES IN CHINA——Taking Benxi City as an Example
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作者 崔凤军 杨新军 《Chinese Geographical Science》 SCIE CSCD 1998年第4期56-64,共0页
I.INTRODUCTIONCitiesarethesymbolsofhuman’scivilization,thespatialcariersofeconomyandthesourcesofregionalecon... I.INTRODUCTIONCitiesarethesymbolsofhuman’scivilization,thespatialcariersofeconomyandthesourcesofregionaleconomicactivities(Gu... 展开更多
关键词 SUSTAINABLE DEVELOPMENT seriously polluted CITY urban environment environmental POLLUTION Benxi CITY in China
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A new technology for harnessing the dye polluted water and dye collection in a chemical factory
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作者 PU Jiang-ping PU Pei-min +3 位作者 HU Chun-hua QIAN Jun-long PU Ju-xing HUA Ji-kang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第2期198-200,共3页
A new technology for harnessing the dye polluted water and dye collection was developed. It is based on the enhanced evaporation by using solar, wind and air temperature energy and additional heat\|electric energy. It... A new technology for harnessing the dye polluted water and dye collection was developed. It is based on the enhanced evaporation by using solar, wind and air temperature energy and additional heat\|electric energy. It consists of four parts: (1)evaporation carrier system (evaporation carrier and frame for evaporation carrier) for polluted water; (2)polluted water circulating system (pumping\|spraying\|collecting); (3)heating system; (4)workshop with polluted water reservoir\|tanks and rainfall prevention roof. The polluted water was (heated in case necessary) sprayed to the evaporation carrier system and the water was evaporated when it moved in the space and downward along the carrier mainly by using natural (solar, wind and air temperature energy). In case, when there is no roof for the carrier system, the polluted water can be stored in the reservoirs (storage volume for about 20 days). The first 10\25 mm rainfall also need to be stored in the reservoirs to meet the state standard for discharging wastewater. The dye may be collected at the surface in the reservoir\|tanks and the crystallized salt may be collected at the bottom plate. The black\|color wastewater released by the factory is no more discharged to the surface water system of Taihu Lake Basin. About 2 kg dye and 200 kg industrial salt may be collected from each tone of the polluted water. The non\|pollution production of dye may be realized by using this technology with environmental, economical and social benefits. 展开更多
关键词 DYE polluted WATER harnessing DYE COLLECTION TECHNOLOGY
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Hydrophobicity changes of polluted silicone rubber introduced by spatial and dose distribution of plasma jet
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作者 李爽 郭新正 +2 位作者 付永强 李健俊 张若兵 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第4期53-60,共8页
The hydrophobicity of polluted silicone rubber was improved rapidly under plasma jet treatment.It is an important phenomenon of the interaction between the plasma jet and the porous surface,and shows a wide applicatio... The hydrophobicity of polluted silicone rubber was improved rapidly under plasma jet treatment.It is an important phenomenon of the interaction between the plasma jet and the porous surface,and shows a wide application prospect in the power system.In this process,the spatial characteristics and dose of plasma jet are very important.Therefore,the variation of hydrophobicity of polluted silicone rubber under plasma jet treatment was studied,and the spatial characteristics and dose of plasma jet on polluted silicone rubber were also investigated in the work.The results show that the surface property(hydrophilic or hydrophobic)depended on the dose of plasma applied to the surface.The effective treated area was a circle,and the contact angles changed along the radial direction of the circle.This was attributable to the diffusion of plasma bullets on the surface and the distribution of plasma species.The plasma dose could be characterized by the energy density of the plasma applied on the surface.With the increase of plasma dose,the surface contact angles first increased rapidly and then decreased gradually. 展开更多
关键词 plasma jet polluted silicone rubber HYDROPHOBICITY plasma dose energy density spatial distribution
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Testing the Efficiency of Acacia Bark (Galool-Asal) as Disinfectant for Polluted Waters
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作者 M. K. Fayyad 《Journal of Water Resource and Protection》 2014年第3期157-164,共8页
Acacia bark efficiency for disinfecting polluted water for the purpose of using it for drinking purposes was tested. Five polluted water samples were collected from different locations in Jordan, namely, King Abdullah... Acacia bark efficiency for disinfecting polluted water for the purpose of using it for drinking purposes was tested. Five polluted water samples were collected from different locations in Jordan, namely, King Abdullah Canal, an Agricultural pond in the Jordan Valley, Yajouz wells, Hazeir spring, and Wadi-Seer spring. Different volumes of the water samples were treated with 10 g of the shredded acacia bark (obtained from Somalia) for different retention times. The volumes used were 1 L, 2.5 L, and 5 L and the detention times were 2, 4, and 24 hours. The samples were tested for total coliform, E. coli, electrical conductivity, pH, total dissolved solids, turbidity and color before and after treatment with the acacia bark. Results revealed that the optimum conditions for disinfection were: 1 L polluted water treated with 10 g acacia bark for 24 hours. Log removals of about 2.5 for E. coli were obtained under these conditions. Higher removals could be achieved by using larger amounts of the acacia bark, but the chemical water quality regarding turbidity and color will not be suitable for drinking purposes and levels of tannic acids present in the acacia bark might reach toxic levels. Toxic levels will not be reached if 1 glass of water/kg body weight every 4 - 5 hours daily is consumed. 展开更多
关键词 ACACIA BARK WATER DISINFECTION DISINFECTION EFFICIENCY E. coli polluted WATER Drinking WATER Availability
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Fractal Analysis on the Spatial Structure of Land Use Patterns in a Non-Point Source Polluted Area in Southern China
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作者 RONG Kun 《Journal of Landscape Research》 2019年第3期19-22,共4页
Based on the TM remote sensing interpretation of land use data of a non-point source polluted area in southern China in 2015, supported by ArcGIS and the fractal theory, this paper established the perimeter-area fract... Based on the TM remote sensing interpretation of land use data of a non-point source polluted area in southern China in 2015, supported by ArcGIS and the fractal theory, this paper established the perimeter-area fractal equation of the spatial structure of land use types, quantitatively calculated the fractal dimension and stability index of various land use types in this non-point source polluted area in 2015, and analyzed the spatial structure characteristics of land use types. The results showed that the fractal dimension values of the different land use types in the research area ranged 1.141–1.657, and the whole fractal dimension of the research area was 1.206. To be specific, the fractal dimension values of unused land, grass land and rural residential land were high, and the fractal dimension values of dry land, paddy filed and waters were low, and the fractal dimension values of urban land, industrial traffic construction land and forest land were moderate. The area of the land use types whose stability index values were 0.2–0.4 accounted for 89.5% of total area, suggesting that the stability of the spatial structure of land use types of Beibei District in 2015 was not high generally. The rural residential land and urban land of the research area should be planned and managed more properly from now on. 展开更多
关键词 LAND use type SPATIAL structure FRACTAL DIMENSION Stability index Non-point SOURCE polluted area
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Oil Pollutants Degradation of Nano-MgO in Micro-Polluted Water
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作者 Meng-Fu Zhu Cheng Deng +4 位作者 Hong-Bo Su Xiu-Dong You Lu Zhu Ping Chen Ying-Hai Yuan 《Computational Water, Energy, and Environmental Engineering》 2013年第3期12-15,共4页
The removal of oil pollutants from water and purifying process of oil-polluted water are studied through catalytic degradation method with nano-MgO. The results indicated that catalytic degradation effect of nano-MgO ... The removal of oil pollutants from water and purifying process of oil-polluted water are studied through catalytic degradation method with nano-MgO. The results indicated that catalytic degradation effect of nano-MgO on the oil pollutants was associated with dosage of nano-MgO, pH and water temperature. When oil content was 1.8 mg/L, 0.17 g nano-MgO was used and the removal rate of oil was 93.92%. Furthermore, nano-Mgo was a non-photosensitive catalyst. GC/MS analysis showed that the amount of petroleum-based pollutants in water was reduced 73.77% from the previous 61 kinds to 16 kinds, and the total peak area was reduced 96.05% after catalytic degradation of nano-MgO. Therefore, nano-MgO has an excellent effect on the catalytic degradation of oil pollutants and can be applied in the treatment of oil wastewaters. 展开更多
关键词 Nano-MgO OIL POLLUTANTS CATALYTIC DEGRADATION MICRO-polluted WATER WATER Treatment
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Soil Quality Evaluation of Hydrocarbon Polluted Parcels
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作者 Margarita Teutli León Marco Antonio Cruz Gómez +1 位作者 José Castillo Román Andrés Sánchez 《Journal of Geoscience and Environment Protection》 2022年第9期27-41,共15页
For hydrocarbon polluted soils that underwent bioremediation it is important to assess its condition after a period of time, but it is more useful when there is an opportunity of comparison against an unpolluted soil ... For hydrocarbon polluted soils that underwent bioremediation it is important to assess its condition after a period of time, but it is more useful when there is an opportunity of comparison against an unpolluted soil and an untreated polluted one. This paper provides a comparison of three adjacent parcels, being the first clean, the second polluted and bioremediated, the third polluted and left to natural attenuation. Study was conducted determining pH, electrical conductivity, carbonates, soil organic matter, chemical oxygen demand, eight anions, and twelve metals. Data were compared against those references for agricultural soils found in the Mexican NOM-021. A Pearson correlation was applied to find coincidences between the three parcels, obtained results allowed to say that bioremediated parcel allowed for most uniform pH, negligible salinity risk, and medium content of soil organic matter, but treatment has enabled heavy metal accumulation since its values are higher in respect to the other parcels. Natural attenuated parcel has some spots with lower pH, a moderately saline risk, a high content of soil organic matter, and lower content of heavy metals. The clean or unaffected parcel exhibit the higher pH values, a slightly saline condition, soil organic matter ranges from high to very high content, heavy metals content is medium, but no reaching dangerous levels. An important assessment is that bioremediation has enhanced the bioavailability of soil organic matter but it is not similar to the values in the unpolluted parcel. 展开更多
关键词 Soil Quality Hydrocarbon Pollution Soil Unpolluted BIOREMEDIATION Natural Attenuation
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TV History is Diluted, Polluted
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作者 Jing Yan,China Daily 《China Today》 1995年第6期63-63,共1页
TVHistoryisDiluted,PollutedJingYan,ChinaDailyHistoricalmovies,soapoperasandnovelshavebeenfloodingChina'smass... TVHistoryisDiluted,PollutedJingYan,ChinaDailyHistoricalmovies,soapoperasandnovelshavebeenfloodingChina'smassmedia,especiallyo... 展开更多
关键词 TV History is Diluted polluted
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Evaluation of ecological risk and primary empirical research on heavy metals in polluted soil over Xiaoqinling gold mining region,Shaanxi,China 被引量:33
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作者 吴耀国 徐友宁 +1 位作者 张江华 胡思海 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第4期688-694,共7页
Soil,crop and residents'hair over Xiaoqinling gold mining region,China,which was selected as a case study,were sampled and analyzed for Hg,Cd,Pb,Cu,Cr,As and Zn concentrations.The concentrations of heavy metals in... Soil,crop and residents'hair over Xiaoqinling gold mining region,China,which was selected as a case study,were sampled and analyzed for Hg,Cd,Pb,Cu,Cr,As and Zn concentrations.The concentrations of heavy metals in soil or crop and hair samples were used to assess their potential ecological risks,or to find the responses to these metals as evidences to prove the potential risk was coming down to observed harm,respectively.The results showed that,these metals in soil were ranked by severity of ecological risk as Hg>Cd>Pb>Cu>Cr>As>Zn,based on their single-element indexes.In the view of the potential ecological risk indexes,of all soil samples,about half had significantly high or high potential ecological risk,which covered more than 74%of the studied region.Most of the risks were 97.41%from Hg,Pb and Cd,especially,84.37%from Hg.Both the single-element and potential ecological risk indexes indicated that,the ecological risk grades had a special spatial characteristic,and increased from northwest to southeast generally.This was agreed with the spatial distribution of the strength in gold mining activities over the studied region.The concentrations of Hg and Pb were higher than their relative backgrounds in the corps,and were even 9.48 and 25.09 times higher than their relative backgrounds in residents'hair,respectively.All these showed that the heavy metals in the soil had a high potential ecological risk,especially,had been affecting these crops'growing and yield,and even the residents'health through food strains.Obviously,these metals'potential ecological harm had been coming down to observed harm to the ecology. 展开更多
关键词 gold mining activity soil pollution heavy metal potential ecological risk
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Major environmental and ecotoxicological processes of heavy metals in Lean River polluted by discharges from mining activities 被引量:5
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作者 Wang Zi\|jian SKLEAC, Research Center for Eco\|Environmental Sciences, Chinese Academy of Sciences, Beijing\ 100085, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第3期322-327,共6页
This paper summarizes the major environmental and ecotoxicological processes of heavy metals pollution from Dexing Copper Mine in Jiangxi Province based on various findings in the Cooperative Ecological Research Proje... This paper summarizes the major environmental and ecotoxicological processes of heavy metals pollution from Dexing Copper Mine in Jiangxi Province based on various findings in the Cooperative Ecological Research Project (CERP; Tang, 1994). It shows the knowledge necessary to elucidate metal pollution and its ecological implications. Processes devoted to the ecological implication include generation of acid mine drainage, formation of secondary minerals from precipitation, temporal and spatial distribution of metal pollutants in sediments and relevant toxicity, as well as ecosystem alternation which may relate to chemical pollution.\; From the results, it was stated that the major emphasis should be placed on the environmental processes associated with sediment pollution by heavy metals. It shows that ad/desorption on the inorganic minerals, such as Fe/Al oxyhydroxides, play an important role in the immobilization of heavy metals in this river. There were clear indications that metal pollution has resulted in the toxicological and ecological consequences and there would be the risk of secondary pollution in the way of mobilization of bound metals to the overlying water when environmental conditions are varied. 展开更多
关键词 HEAVY metal POLLUTION mobility TOXICITY ecotoxicology.
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From highly polluted inland city of China to"Lanzhou Blue":The air-pollution characteristics 被引量:2
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作者 SuPing Zhao Ye Yu DaHe Qin 《Research in Cold and Arid Regions》 CSCD 2018年第1期12-26,共15页
Air quality was improved considerably and the so-called"Lanzhou Blue"appeared frequently in Lanzhou due to implementation of some strict emission-control measures in recent years.To better understand whether... Air quality was improved considerably and the so-called"Lanzhou Blue"appeared frequently in Lanzhou due to implementation of some strict emission-control measures in recent years.To better understand whether the concentration of each air pollutant had decreased significantly and then give some suggestions as to urban air-quality improvement in the near future,the variations of the Air Quality Index(AQI)and six criterion air pollutants(PM_(2.5),PM_(10),CO,SO_2,NO_2,and O_3)at five state-controlled monitoring sites of Lanzhou were studied from 2013 to 2016.The AQI,PM_(2.5),PM_(10),and SO_2 gradually decreased from 2013 to 2016,while CO and NO_2 concentrations had slightly increasing trends,especially in urban areas,due to the large number of motor vehicles,which had an annual growth rate of 30.87%.The variations of the air pollutants in the no-domestic-heating season were more significant than those in the domestic-heating season.The increase of ozone concentration for the domestic-heating season at a background station was the most significant among the five monitoring sites.The vehicle-exhaust and ozone pollution was increasingly severe with the rapid increase in the number of motor vehicles.The particulate-matter pollution became slight in the formerly highly polluted Lanzhou City.Some synergetic measures in urban and rural areas of Lanzhou should be taken by the local government in the near future to control fine particulate-matter(PM_(2.5))and ozone pollution. 展开更多
关键词 LANZHOU BLUE PARTICULATE matter OZONE pollution temporal-spatial variation
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Graphene oxide influences bacterial community and soil environments of Cd-polluted Haplic Cambisols in Northeast China 被引量:1
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作者 Jiaxin Ru Guoyou Chen +2 位作者 Yong Liu Ying Sang Jinfeng Song 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第4期1699-1711,共13页
Graphene oxide(GO),a carbon nanomaterial that is widely used in the environment and other industries,may pose potential risks to ecosystems,especially the soil ecosystem.Some soils in Northeast China are frequently po... Graphene oxide(GO),a carbon nanomaterial that is widely used in the environment and other industries,may pose potential risks to ecosystems,especially the soil ecosystem.Some soils in Northeast China are frequently polluted with cadmium(Cd) metal.However,there is no study on the influence of GO on the Cd-contaminated soil microbial community and soil chemical properties.In this study,Cd(100 mg kg^(-1))-polluted soils were treated with different concentrations of GO(0,25,50,150,250,and 500 mg L^(-1),expressed as T1,T2,T3,T4,T5,and T6,respectively) for 40 days.The treatment without Cd pollution and GO served as the control(CK).Then,we investigated the influence of the GO concentrations on the bacterial community and chemical properties of Cd-polluted Haplic Cambisols,the zonal soil in Northeast China.After GO addition,the richness and diversity indexes of the bacterial community in Cd-contaminated Haplic Cambisols initially increased by 0.05-33.92% at 25 mg L^(-1),then decreased by0.07-2.37% at 50 mg L^(-1),and then increased by 0.01-24.37%within 500 mg L^(-1) again.The species and abundance of bacteria varied with GO concentration,and GO significantly increased bacterial growth at 25 and 250 mg L^(-1).GO treatments influenced the bacterial community structure,and the order of similarity of the bacterial community structure was as follows:T4=T5> T1=T6> T2> T3> CK.Proteobacteria and Acidobacteria were the dominant bacteria,accounting for 36.0% and 26.2%,respectively,of soil bacteria.Different GO treatments also significantly affected the metabolic function of bacteria and further influenced the diversity of the bacterial community structure by affecting several key soil chemical properties:soil pH,organic matter and available potassium,phosphorus,and cadmium.Our results provide a theoretical basis for scientific and comprehensive evaluation of the environmental impacts of GO on the zonal forest soils of Northeast China. 展开更多
关键词 Cadmium pollution Haplic cambisols Graphene oxide Bacterial community Soil environmental factors
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Comparison of Mental Health Status of People Exposed to Noise Pollution with People in Non-Polluted Areas of Sari 被引量:1
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作者 Abbas Masoudzadeh Pezhman Hadinezhad Maede Gooran 《Health》 2017年第5期839-848,共10页
Noise pollution in psychological terms is defined as an unpleasant, undesirable or unwanted sound and in quantitative terms, it is a sound possessing all different wavelengths and intensities with no certain combinati... Noise pollution in psychological terms is defined as an unpleasant, undesirable or unwanted sound and in quantitative terms, it is a sound possessing all different wavelengths and intensities with no certain combination which is unpleasant to ear. The present study was conducted to compare the mental health status of people exposed to noise pollution with people in non-polluted areas of Sari. The sample population in the present descriptive study included 200 people selected by Random sampling method. Then, Sari was divided into four areas in terms of noise pollution, and after implementing GHQ-28 questionnaire (which reliability and validity have been confirmed), general health as well as mental health of samples were compared with each other. Data analysis was conducted based on occupation and residence location using variance analysis tests and t-Test for quantitative data and Square-test for qualitative data. Complaints about physical difficulties in traders’ group working in non-polluted environment are lower than traders’ group working in an environment exposed to noise pollution. These complaints among residents in non-polluted areas are at the lowest level. In overall review, the prevalence and average of mental health disorders amongst traders in areas exposed to noise pollution are higher than traders in non-polluted areas. Average complaints about physical difficulties, anxiety and sleeping problems, problems with social performance, depression and in general average mental and physical disorders are higher in resident and working groups in areas exposed to noise pollution, however, only complaints about physical difficulties are statistically significant. 展开更多
关键词 Noise POLLUTION MENTAL HEALTH
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Analysis of a Delayed Stochastic One-Predator Two-Prey Population Model in a Polluted Environment 被引量:1
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作者 Mengwei Li Yuanfu Shao Yafei Yang 《Journal of Applied Mathematics and Physics》 2019年第10期2265-2282,共18页
This paper is concerned with the dynamics of a delayed stochastic one-predator two-prey population model in a polluted environment. We show that there exists a unique positive solution that is permanent in time averag... This paper is concerned with the dynamics of a delayed stochastic one-predator two-prey population model in a polluted environment. We show that there exists a unique positive solution that is permanent in time average under certain conditions. Moreover, the global attractively of system is studied. Finally, some numerical simulations are given to illustrate the main results. 展开更多
关键词 Random PERTURBATIONS TIME DELAYS Pollution PERMANENT in TIME Average
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THE SURVIVAL ANALYSIS FOR GALLOPIN'S SYSTEM IN A POLLUTED ENVIRONMENT
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作者 何泽荣 马知恩 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第8期921-928,共8页
The long_time behavior of the consumer population in a Gallopin’s system, located in a polluted environment, was studied. Firstly, a mathematical model, i.e.,a nonlinear ordinary differential system, was made by taki... The long_time behavior of the consumer population in a Gallopin’s system, located in a polluted environment, was studied. Firstly, a mathematical model, i.e.,a nonlinear ordinary differential system, was made by taking a constant catch rate into account in model of MA Zhi_en. Secondly, using the extension theorem and the comparison theorem, the bound of the system was estimated. Then, the effect of the pollution on the consumer population was discussed by the use of calculus and qualitative theory of differential equation. Finally, some conditions for weak persistence in the mean and extinction are found out. The threshold between persistence and extinction can be established in some cases. 展开更多
关键词 Gallopin’s SYSTEM CONSUMER POPULATION POLLUTION PERSISTENCE EXTINCTION
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