The integration of surface filtration and catalytic decomposition functions in catalytic bags enables the synergistic removal of multiple pollutants(such as dust,nitrogen oxide,acid gases,and dioxins)in a single react...The integration of surface filtration and catalytic decomposition functions in catalytic bags enables the synergistic removal of multiple pollutants(such as dust,nitrogen oxide,acid gases,and dioxins)in a single reactor,thus effectively reducing the cost and operational difficulties associated with flue gas treatment.In this study,Mn-Ce-Sm-Sn(MCSS)catalysts were prepared and loaded onto hightemperature resistant polyimide(P84)filter through ultrasonic impregnation to create composite catalytic filter.The results demonstrate that the NO conversion rates of the composite catalytic filter consistently achieve above 95%within the temperature range of 160-260℃,with a chlorobenzene T_(90)value of 230℃.The ultrasonic impregnation method effectively loaded the catalyst onto the filter,ensuring high dispersion both on the surface and inside the filter.This increased exposure of catalyst active sites enhances the catalytic activity of the composite catalytic filter.Additionally,increasing the catalyst loading leads to a gradual decrease in permeability,an increase in pressure drops and the long residence time of the flue gas,thereby improving catalytic activity.Compared to ordinary impregnation methods,ultrasonic impregnation improves the bonding strength between the catalyst and filter,as well as the permeability of the composite catalytic filter under the same loading conditions.Overall,this study presents a novel approach to prepare composite catalytic filter for the simultaneous removal of NO and chlorobenzene at low temperatures.展开更多
The rapid development of rare earth metal elements in the field of photocatalysis is due to their excellent optical and physicochemical properties.Benefiting from the unique external electronic structure of 4f_15d_16S...The rapid development of rare earth metal elements in the field of photocatalysis is due to their excellent optical and physicochemical properties.Benefiting from the unique external electronic structure of 4f_15d_16S_2,superior electronegativity of the 4f orbitals,and strong oxygen storage-release ability in Ce^(4+)/Ce^(3+)reversible pairs,cerium dioxide(CeO_(2))has attracted increasing interest from scientists.Nevertheless,the fast recombination of photoinduced electron-hole pairs and wide energy band gap of bare CeO_(2)significantly limit its practical applications.To overcome the above drawbacks,the construction of heterojunctions has been developed to broaden the absorption spectrum and accelerate the charge transfer.This review presents a mini-review of the synthesis of CeO_(2)-based heterojunctions including typeⅡ,Z-scheme,and S-scheme photocatalysts,as well as the corresponding applications in photocatalytic bactericidal and antitumor therapy.Finally,the latest advancements and potential perspectives on their future development are also discussed.展开更多
For purpose of purification and enrichment, environmental samples usually need to be pretreated before analysis because of low concentration of residual organic matters. Solid-phase extraction （SPE） is one of the fr...For purpose of purification and enrichment, environmental samples usually need to be pretreated before analysis because of low concentration of residual organic matters. Solid-phase extraction （SPE） is one of the frequently used methods of pretreatment. This article introduces the methodological principle and flow channel of SPE as well as the categories of frequently used small extraction column, analyzes the application of online SPE technology in environmental analysis, generalizes the advantages of online SPE and sets forth its developmental trend.展开更多
Understanding the hydrochemical characteristics and genesis mechanisms of strontium-rich groundwater is pivotal for supporting the exploitation and utilization of natural strontium-rich groundwater.In this research,27...Understanding the hydrochemical characteristics and genesis mechanisms of strontium-rich groundwater is pivotal for supporting the exploitation and utilization of natural strontium-rich groundwater.In this research,27 groundwater samples were collected.By analyzing major ion chemistry and strontium isotope data,and considering the hydrogeological context,various analytical approaches,including multivariate statistics,ion ratios,and isotopes,were used to reveal the characteristics and genesis mechanisms of strontium-rich groundwater in the study area.The findings indicate that the predominant hydrochemical type of groundwater is HCO_(3)-Ca,with Ca^(2+)and HCO_(3)^(-)as the primary cations and anions.The hydrochemistry of the strontium-rich groundwater is predominantly influenced by rock weathering processes.A combination of factors,including ion exchange,and anthropogenic activities,shapes the compositional characteristics of the groundwater in the region.The dissolution of calcite due to weathering emerges as the principal source of strontium in the groundwater.While ion exchange processes are not conducive to strontium enrichment in groundwater,their effect is relatively limited.The impact of human activities on the groundwater is minor.展开更多
Based on the monitoring of five heavy metal elements in the surface sediments of the Pearl River in South China, potential toxicity of the heavy metals was assessed using consensus-based sediment quality guidelines （...Based on the monitoring of five heavy metal elements in the surface sediments of the Pearl River in South China, potential toxicity of the heavy metals was assessed using consensus-based sediment quality guidelines （SQGs） method and geo-accumulation （Igeo） index method. The monitoring results showed the heavy metal concentrations were significantly and positively correlated with each other, demonstrating a common trend in variation of concentration in the surface sediments. The assessment using the consensus-based SQGs method showed the potential toxicity of Cu was the highest, and Cd was the lowest. The evaluation based on mean probable effect concentration （PEC） quotient showed the region was seriously polluted with high toxicity heavy metals. Correlation analysis revealed a significant and positive correlation between the mean PEC quotient and the average of Igeo with a correlation coefficient of 0.926 （n = 23, P 〈 0.01）. In conclusion, the consensus-based SQGs and mean PEC quotient are applicable to assess potential toxicity risks of heavy metals in freshwater sediments in the Pearl River.展开更多
To evaluate the potential benefits of biomass use for air pollution control, this paper identified and quantified the emissions of major reactive organic compounds anticipated from biomass-fired industrial boilers. Wo...To evaluate the potential benefits of biomass use for air pollution control, this paper identified and quantified the emissions of major reactive organic compounds anticipated from biomass-fired industrial boilers. Wood pellets(WP) and straw pellets(SP) were burned to determine the volatile organic compound emission profiles for each biomass-boiler combination. More than 100 types of volatile organic compounds(VOCs) were measured from the two biomass boilers. The measured VOC species included alkanes, alkenes and acetylenes, aromatics, halocarbons and carbonyls. A single coal-fired boiler(CB) was also studied to provide a basis for comparison. Biomass boiler 1(BB1) emitted relatively high proportions of alkanes(28.9%–38.1% by mass) and alkenes and acetylenes(23.4%–40.8%),while biomass boiler 2(BB2) emitted relatively high proportions of aromatics(27.9%–29.2%)and oxygenated VOCs(33.0%–44.8%). The total VOC(TVOC) emission factors from BB1(128.59–146.16 mg/kg) were higher than those from BB2(41.26–85.29 mg/kg). The total ozone formation potential(OFP) ranged from 6.26 to 81.75 mg/m^3 with an average of 33.66 mg/m^3 for the two biomass boilers. The total secondary organic aerosol potential(SOAP) ranged from 61.56 to 211.67 mg/m^3 with an average of 142.27 mg/m^3 for the two biomass boilers.The emission factors(EFs) of TVOCs from biomass boilers in this study were similar to those for industrial coal-fired boilers with the same thermal power. These data can supplement existing VOC emission factors for biomass combustion and thus enrich the VOC emission inventory.展开更多
Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data...Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data of Taibus Banner, Duolun county and Zhengxiangbai Banner in the Inner Mongolia autonomous region of China, we identified the impact of livelihood diversification on ecosystems in these agro-pastoral areas by using the ecological footprint theory and methodology together with the one-way analysis of variance （ANOVA） and correlation analysis methods. In 2011, the total ecological footprint of consumption （EFC） was 0.665 g hm2, and the total ecological footprint of production （EFP） was 2.045 g hm2, which was more than three times the EFC. The ecological footprint of arable land consumption （EFAC） accounted for a large proportion of the EFC, and the ecological footprint of grassland production （EFGP） occupied a large proportion of the EFP. Both the ecological footprint of grassland consumption （EFGC） and EFGP had a significant positive correlation with the income, indicating that income was mainly depended on livestock production and the households with higher incomes consumed more livestock prod- ucts. The full-time farming households （FTFHs） had the highest EFP, ecological footprint of arable land production （EFAP）, EFGP and EFGC, followed by the part-time farming households （PTFHs） and non-farming households （NFHs）, which indicated that part-time farming and non-farming employment reduced the occupancy and con- sumption of rural households on local ecosystems and natural resources to some extent. When farming households engaged in livestock rearing, both the EFAP and EFAC became smaller, while the EFP, EFC, EFGC and EFGP increased significantly. The differences in ecological footprints among different household groups should be taken into account when making ecosystem conservation policies. Encouraging the laborers who have the advantages of participating in non-farming employment to move out of the rural areas and increasing the diversification of liveli- hoods of rural households are important in reducing the environmental pressures and improving the welfare of households in the study area. Moreover, grassland should be utilized more effectively in the future.展开更多
It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reason...It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reasons.Furthermore,calcium arsenates can also naturally precipitate under some specific environments.However,the transformation process of poorly crystalline calcium arsenates(PCCA)and the stability of these samples under atmospheric CO2 are not yet well understood.This work investigated the transformation process of PCCA produced by using different neutralization reagents(CaO vs.NaOH)with various Ca/As molar ratios at pH 7-12 in the presence of atmospheric CO2.After aging at room temperature for a period of time,for samples neutralized with NaOH and precipitated at pH 10 and 12,release of arsenic back into the liquid phase occurred.In contrast,for the samples precipitated at pH 8,the aqueous concentration of arsenic was observed to decrease.XRD,Raman,and SEM results suggested that the formation of various types of crystalline calcium carbonates and/or calcium arsenates controls the arsenic behavior.Moreover,the application of lime may enhance the stability of the generated PCCA.However,no matter what neutralization reagent is used,the stability of the generated PCCA is still of concern.展开更多
Volatile organic compounds(VOCs)play an important role in the formation of ground-level ozone and secondary organic aerosol(SOA),and they have been key issues in current air pollution prevention and control in China.C...Volatile organic compounds(VOCs)play an important role in the formation of ground-level ozone and secondary organic aerosol(SOA),and they have been key issues in current air pollution prevention and control in China.Considerable attention has been paid to industrial activities due to their large and relatively complex VOCs emissions.The present research aims to provide a comprehensive review on whole-process control of industrial VOCs,which mainly includes source reduction,collection enhancement and end-pipe treatments.Lower VOCs materials including water-borne ones are the keys to source substitution in industries related to coating and solvent usage,leak detection and repair(LDAR)should be regarded as an efficient means of source reduction in refining,petrochemical and other chemical industries.Several types of VOCs collection methods such as gas-collecting hoods,airtight partitions and others are discussed,and airtight collection at negative pressure yields the best collection efficiency.Current end-pipe treatments like UV oxidation,low-temperature plasma,activated carbon adsorption,combustion,biodegradation,and adsorption-combustion are discussed in detail.Finally,several recommendations are made for future advanced treatment and policy development in industrial VOCs emission control.展开更多
Allelopathic effects of submerged macrophytes against algae are affected by many environmental factors which can only be measured one by one by traditional methods. Box-Behnken design of response surface methodology w...Allelopathic effects of submerged macrophytes against algae are affected by many environmental factors which can only be measured one by one by traditional methods. Box-Behnken design of response surface methodology was used to optimize three environmental factors （temperature, light intensity and total dissolved solids） of allelopathic effects of Potarnogeton pectinatus against Microcystis aeruginosa at the same time. By solving the regression equation and analyzing the response surface contour plots, the optimal conditions of the relatively inhibitory rate of Microcystis aeruginosa were that the temperature was 23℃, the light intensity was 2 700 lx and the total dissolved solids were 4 415 mg/L. Under these conditions, the optimal value of relatively inhibitory rate of Microcystis aeruginosa was 81.9%. According to validation experiments, the results of analysis indicated that the experimental values fitted well with the predicted ones.展开更多
The carbon cycle of forest ecosystems plays a key role in regulating CO2 concentrations in the atmosphere. Research on carbon storage estimation of forest ecosystems has become a major research topic. However, carbon ...The carbon cycle of forest ecosystems plays a key role in regulating CO2 concentrations in the atmosphere. Research on carbon storage estimation of forest ecosystems has become a major research topic. However, carbon budgets of subtropical forest ecosystems have received little attention. Reports of soil carbon storage and topographic heterogeneity of carbon storage are limited. This study focused on the Jinggang Mountain National Nature Reserve as an example of a mid-subtropical forest and evaluated soil and vegetation carbon storage by field sampling combined with GIS, RS and GPS technology. We classified the forest into nine forest types using ALOS high-resolution remote sensing images. The evergreen broad-leaved forest has the largest area, occupying 26.5% of the total area, followed by coniferous and broad-leaved mixed forests and warm temperate coniferous forest, occupying 24.2 and 22.9%, respectively. The vegetation and soil carbon storage of the whole forest ecosystem were 1,692,344 and 5,514,707 t, with a carbon density of 7.4 and 24.2 kg/m^2, respectively, which suggests that the ecosystem has great carbon storage capacity. The topographic heterogeneity of the carbon storage was also analysed. The largest vegetation storage and soil storage is at 700–800 and 1000–1100 m, respectively. The vegetation carbon storage is highest in the southeast, south and southwest.展开更多
The mass concentration and major chemical components of fine particulate matter were measured before,during and after Beijing＇s massive parade commemorating 70th anniversary of the Chinese Victory in World War II on ...The mass concentration and major chemical components of fine particulate matter were measured before,during and after Beijing＇s massive parade commemorating 70th anniversary of the Chinese Victory in World War II on September 3,2015.Regional emission inventory,positive matrix factorization（PMF）,observations from space and backward air mass trajectories were jointly applied to identify the major pollution sources and their temporal and spatial variations.The contributions of emissions variations and the meteorological conditions related to the＂parade blue＂phenomenon in Beijing and its surrounding areas were investigated in detail.The main cause of the decreased PM（2.5）mass concentration was attributed to the absolute reduction in emissions of primary air pollutants.The chemical composition of PM（2.5）varied significantly before,during and after the parade.Fugitive dust particles were well controlled,the secondary formation of PM（2.5）was reduced along with the controlled gaseous precursors＇emissions from vehicles and industrial sources during the temporary intensified control period.During the parade period,the SO2and NO2column concentrations in Beijing and the surrounding areas decreased sharply,indicating that the coordinated reduction in primary emissions from the surrounding areas of Beijing played an important role in lowering the ambient concentration of SO2and NO2and accordingly lowered PM（2.5）and improved the regional air quality.A comparison of the temperature,humidity,and wind speed and direction during the same periods in 2014 and 2015 showed that the meteorological conditions positively influenced the achievement of＂parade blue＂.展开更多
Organochlorine pesticides(OCPs)have received much attention due to their toxicity.Reliable methods to monitor their residues in the environment are needed.Here,magnetic polyamidoamine dendrimers were prepared by co-pr...Organochlorine pesticides(OCPs)have received much attention due to their toxicity.Reliable methods to monitor their residues in the environment are needed.Here,magnetic polyamidoamine dendrimers were prepared by co-precipitation,Michael addition,and amidation.The magnetic polyamidoamine dendrimers demonstrated good adsorption ability for OCPs—this feature was utilized to construct a sensitive tool for monitoring OCPs in water samples.The proposed method provided remarkable linearity from 0.1 to 500μg/L and satisfactory limits of detection from 0.012 to 0.029μg/L.The spiked recoveries of the four target analytes were 91.8%-103.5%with relative standard deviations less than 4.5%.The magnetic materials had good reusability.The results indicated that the resulting method was an efficient,easy,rapid,economical,and eco-friendly tool for monitoring OCPs in aqueous samples.展开更多
Anatomical characteristics have been proven useful for extracting climatic signals. To examine the climatic signals recorded by tree-ring cell features in the Changbai Mountains, we measured cell number and cell lumen...Anatomical characteristics have been proven useful for extracting climatic signals. To examine the climatic signals recorded by tree-ring cell features in the Changbai Mountains, we measured cell number and cell lumen diameter, in addition to ring widths, of Korean pine （Pinus koraiensis） tree rings at sites of varied elevation, and we developed chronologies of cell number （CN）, mean lumen diameter （MLD）, maximum lumen diameter （MAXLD） and tree-ring width （TRW）. The chronologies were correlated with climatic factors monthly mean tem- perature and the sum of precipitation. As shown by our analysis, the cell parameter chronologies were suitable for dendroclimatology studies. CN and TRW shared relatively similar climatic signals which differed from MLD and MAXLD, and growth-climate relationships were elevation- dependent, as shown by the following findings： （1） at each elevation, MLD and MAXLD recorded different monthly climatic signals from those recorded by TRW for the same climatic factors; and （2） MLD and MAXLD recorded cli- matic factors that were absent middle elevations. Cell lumen effective archive for improving for this study area. from TRW at lower and diameter proved to be an the climate reconstruction展开更多
This paper aims to identify the main driving force for changes of total primary energy consumption in Beijing during the period of 1981-2005.Sectoral energy use was investigated when regional economic structure change...This paper aims to identify the main driving force for changes of total primary energy consumption in Beijing during the period of 1981-2005.Sectoral energy use was investigated when regional economic structure changed significantly.The changes of total primary energy consumption in Beijing are decomposed into production effects,structural effects and intensity effects using the additive version of the logarithmic mean Divisia index (LMDI) method.Aggregate decomposition analysis showed that the major contributor of total effect was made by the production effect fol- lowed by the intensity effect,and the structural effect was rela- tively insignificant.The total and production effects were all posi- tive.In contrast,the structural effect and intensity effect were all negative.Sectoral decomposition investigation indicated that the most effective way to slow down the growth rate of total primary energy consumption (TPEC) was to reduce the production of the energy-intensive industrial sectors and improving industrial en- ergy intensity.The results show that in this period,Beijing's economy has undergone a transformation from an industrial to a service economy.However,the structures of sectoral energy use have not been changed yet,and energy demand should be in- creasing until the energy-intensive industrial production to be reduced and energy intensity of the region reaches a peak.As sequence energy consumption data of sub-sectors are not available, only the fundamental three sectors are considered:agriculture, industry and service.However,further decomposition into secon- dary and tertiary sectors is definitely needed for detailed investi- gations.展开更多
Particles from ambient air and combustion sources including vehicle emission, coal combustion and biomass burning were collected and chemically pretreated with the purpose of obtaining isolated BC（black carbon） samp...Particles from ambient air and combustion sources including vehicle emission, coal combustion and biomass burning were collected and chemically pretreated with the purpose of obtaining isolated BC（black carbon） samples. TEM（transmission electron microscopy）results indicate that BC from combustion sources shows various patterns, and airborne BC appears spherical and about 50 nm in diameter with a homogeneous surface and turbostratic structure. The BET（Barrett-Emmett-Teller） results suggest that the surface areas of these BC particles fall in the range of 3-23 m2/g, with a total pore volume of 0.03-0.05 cm3/g and a mean pore diameter of 7-53 nm. The nitrogen adsorption-desorption isotherms are indicative of the accumulation mode and uniform pore size. O2-TPO（temperature programmed oxidation）profiles suggest that the airborne BC oxidation could be classified as the oxidation of amorphous carbon, which falls in the range of 406-490℃ with peaks at 418, 423 and 475℃,respectively. Generally, the BC characteristics and source analysis suggest that airborne BC most likely comes from diesel vehicle emission at this site.展开更多
Over the past decade,the emission standards and fuel standards in Beijing have been upgraded twice,and the vehicle structure has been improved by accelerating the elimination of 2.95 million old vehicles.Through the f...Over the past decade,the emission standards and fuel standards in Beijing have been upgraded twice,and the vehicle structure has been improved by accelerating the elimination of 2.95 million old vehicles.Through the formulation and implementation of these policies,the emissions of carbon monoxide(CO),volatile organic compounds(VOCs),nitrogen oxides(NO_(x)),and fine particulate matter(PM_(2.5))in 2019 were 147.9,25.3,43.4,and 0.91 kton in Beijing,respectively.The emission factor method was adopted to better understand the emissions characteristics of primary air pollutants from combustion engine vehicles and to improve pollution control.In combination with the air quality improvement goals and the status of social and economic development during the 14th Five-Year Plan period in Beijing,different vehicle pollution control scenarios were established,and emissions reductions were projected.The results show that the emissions of four air pollutants(CO,VOCs,NO_(x),and PM_(2.5))fromvehicles in Beijing decreased by an average of 68% in 2019,compared to their levels in 2009.The contribution of NOx emissions from diesel vehicles increased from 35% in 2009 to 56% in 2019,which indicated that clean and energy-saving diesel vehicle fleets should be further improved.Electric vehicle adoption could be an important measure to reduce pollutant emissions.With the further upgrading of vehicle structure and the adoption of electric vehicles,it is expected that the total emissions of the four vehicle pollutants can be reduced by 20%-41% by the end of the 14th Five-Year Plan period.展开更多
The influences of additives of NH_3,HCl,KOH and CH_3OH on the solvothermal synthesis of the Zn-based metal-organic frameworks(Zn-MOF_5s)were investigated.Powder X-ray diffraction(PXRD),thermal gravimetric analysis(TGA...The influences of additives of NH_3,HCl,KOH and CH_3OH on the solvothermal synthesis of the Zn-based metal-organic frameworks(Zn-MOF_5s)were investigated.Powder X-ray diffraction(PXRD),thermal gravimetric analysis(TGA),Fourier translation infrared spectroscope(FT-IR),N_2adsorption/desorption at 77 K and CO_2sorption measurements were used to characterize the as-prepared Zn-MOF_5s.The experimental results showthat additives of NH_3,CH_3OH,HCl and KOH in the synthesis of the Zn-MOF_5s do not change the underlying topology,but they are extremely sensitive to the pore textural properties,thus changing the CO_2adsorption capacity.Additives would lower the pore width and the surface area,and then lower the CO_2adsorption capacity of Zn-MOF_5s.展开更多
Cooking process can produce abundant volatile organic compounds(VOCs),which are harmful to environment and human health.Therefore,we conducted a comprehensive analysis in which VOCs emissions from multiple cuisines ha...Cooking process can produce abundant volatile organic compounds(VOCs),which are harmful to environment and human health.Therefore,we conducted a comprehensive analysis in which VOCs emissions from multiple cuisines have been sampled based on the simulation and acquisition platform,involving concentration characteristics,ozone formation potential(OFP)and purification efficiency assessments.VOCs emissions varied from 1828.5 to 14,355.1μg/m^(3),with the maximumand minimumvalues fromBarbecue and Family cuisine,respectively.Alkanes and alcohol had higher contributions to VOCs from Sichuan and Hunan cuisine(64.1%),Family cuisine(66.3%),Shandong cuisine(69.1%)and Cantonese cuisine(69.8%),with the dominant VOCs species of ethanol,isobutane and n-butane.In comparison,alcohols(79.5%)were abundant for Huaiyang cuisine,while alkanes(19.7%),alkenes(35.9%)and haloalkanes(22.9%)accounted for higher proportions from Barbecue.Specially,carbon tetrachloride,n-hexylene and 1-butene were the most abundant VOCs species for Barbecue,ranging from 8.8%to 14.6%.The highest OFP occurred in Barbecue.The sensitive species of OFP for Huaiyang cuisine were alcohols,while other cuisines were alkenes.Purification efficiency assessments shed light on the removal differences of individual and synergistic control technologies.VOCs emissions exhibited a strong dependence on the photocatalytic oxidation,with the removal efficiencies of 29.0%–54.4%.However,the high voltage electrostatic,wet purification and mechanical separation techniques played a mediocre or even counterproductive role in the VOCs reduction,meanwhile collaborative control technologies could not significantly improve the removal efficiency.Our results identifiedmore effective control technologies,which were conductive to alleviating air pollution from cooking emissions.展开更多
基金Project supported by the National Key Research and Development Program of China(2021YFB3500600,2021YFB3500605)Natural Science Foundation of Jiangsu Province(BK20220365)+5 种基金Key R&D Program of Jiangsu Province(BE2022142)Natural Science Foundation of the Jiangsu Higher Education Institutions of China(22KJB610002)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX23_1419)Science and Technology Plan of Yangzhou(YZ2022030,YZ2023020)the State Key Laboratory of Clean and Efficient Coal-fired Power Generation and Pollution Control(D2022FK098)。
文摘The integration of surface filtration and catalytic decomposition functions in catalytic bags enables the synergistic removal of multiple pollutants(such as dust,nitrogen oxide,acid gases,and dioxins)in a single reactor,thus effectively reducing the cost and operational difficulties associated with flue gas treatment.In this study,Mn-Ce-Sm-Sn(MCSS)catalysts were prepared and loaded onto hightemperature resistant polyimide(P84)filter through ultrasonic impregnation to create composite catalytic filter.The results demonstrate that the NO conversion rates of the composite catalytic filter consistently achieve above 95%within the temperature range of 160-260℃,with a chlorobenzene T_(90)value of 230℃.The ultrasonic impregnation method effectively loaded the catalyst onto the filter,ensuring high dispersion both on the surface and inside the filter.This increased exposure of catalyst active sites enhances the catalytic activity of the composite catalytic filter.Additionally,increasing the catalyst loading leads to a gradual decrease in permeability,an increase in pressure drops and the long residence time of the flue gas,thereby improving catalytic activity.Compared to ordinary impregnation methods,ultrasonic impregnation improves the bonding strength between the catalyst and filter,as well as the permeability of the composite catalytic filter under the same loading conditions.Overall,this study presents a novel approach to prepare composite catalytic filter for the simultaneous removal of NO and chlorobenzene at low temperatures.
基金Project supported by the National Key Research and Development Program of China(2022YFB3504100,2021YFB3500600)Chunhui Project Foundation of the Education Department of China(202200554)。
文摘The rapid development of rare earth metal elements in the field of photocatalysis is due to their excellent optical and physicochemical properties.Benefiting from the unique external electronic structure of 4f_15d_16S_2,superior electronegativity of the 4f orbitals,and strong oxygen storage-release ability in Ce^(4+)/Ce^(3+)reversible pairs,cerium dioxide(CeO_(2))has attracted increasing interest from scientists.Nevertheless,the fast recombination of photoinduced electron-hole pairs and wide energy band gap of bare CeO_(2)significantly limit its practical applications.To overcome the above drawbacks,the construction of heterojunctions has been developed to broaden the absorption spectrum and accelerate the charge transfer.This review presents a mini-review of the synthesis of CeO_(2)-based heterojunctions including typeⅡ,Z-scheme,and S-scheme photocatalysts,as well as the corresponding applications in photocatalytic bactericidal and antitumor therapy.Finally,the latest advancements and potential perspectives on their future development are also discussed.
文摘For purpose of purification and enrichment, environmental samples usually need to be pretreated before analysis because of low concentration of residual organic matters. Solid-phase extraction （SPE） is one of the frequently used methods of pretreatment. This article introduces the methodological principle and flow channel of SPE as well as the categories of frequently used small extraction column, analyzes the application of online SPE technology in environmental analysis, generalizes the advantages of online SPE and sets forth its developmental trend.
基金supported by the Guangxi Natural Science Foundation(2020GXNSFAA297025)the Guangxi Natural Science Foundation(GuikeAB22080046)+3 种基金the Guangxi Natural Science Foundation(GuikeAB21196050)the National Natural Science Foundation of China(42177075)the Natural Resources Science and Technology Strategic Research Project(2023-ZL-23)the Survey and China Geological Survey(DD20221808 and DD20230547).
文摘Understanding the hydrochemical characteristics and genesis mechanisms of strontium-rich groundwater is pivotal for supporting the exploitation and utilization of natural strontium-rich groundwater.In this research,27 groundwater samples were collected.By analyzing major ion chemistry and strontium isotope data,and considering the hydrogeological context,various analytical approaches,including multivariate statistics,ion ratios,and isotopes,were used to reveal the characteristics and genesis mechanisms of strontium-rich groundwater in the study area.The findings indicate that the predominant hydrochemical type of groundwater is HCO_(3)-Ca,with Ca^(2+)and HCO_(3)^(-)as the primary cations and anions.The hydrochemistry of the strontium-rich groundwater is predominantly influenced by rock weathering processes.A combination of factors,including ion exchange,and anthropogenic activities,shapes the compositional characteristics of the groundwater in the region.The dissolution of calcite due to weathering emerges as the principal source of strontium in the groundwater.While ion exchange processes are not conducive to strontium enrichment in groundwater,their effect is relatively limited.The impact of human activities on the groundwater is minor.
基金from the School of Environmental Science and Engineering, Sun Yat-sen University, for their great contribution tothe project "Water Quality Research of Drinking Water Source in Guangzhou City", which was the Natural Science Foundation of Guangdong Province (No. 031549)
文摘Based on the monitoring of five heavy metal elements in the surface sediments of the Pearl River in South China, potential toxicity of the heavy metals was assessed using consensus-based sediment quality guidelines （SQGs） method and geo-accumulation （Igeo） index method. The monitoring results showed the heavy metal concentrations were significantly and positively correlated with each other, demonstrating a common trend in variation of concentration in the surface sediments. The assessment using the consensus-based SQGs method showed the potential toxicity of Cu was the highest, and Cd was the lowest. The evaluation based on mean probable effect concentration （PEC） quotient showed the region was seriously polluted with high toxicity heavy metals. Correlation analysis revealed a significant and positive correlation between the mean PEC quotient and the average of Igeo with a correlation coefficient of 0.926 （n = 23, P 〈 0.01）. In conclusion, the consensus-based SQGs and mean PEC quotient are applicable to assess potential toxicity risks of heavy metals in freshwater sediments in the Pearl River.
基金supported by the National Natural Science Foundation of China(No.41275135)the Chinese National Key Research and Development Plan(No.2017YFC0212503)
文摘To evaluate the potential benefits of biomass use for air pollution control, this paper identified and quantified the emissions of major reactive organic compounds anticipated from biomass-fired industrial boilers. Wood pellets(WP) and straw pellets(SP) were burned to determine the volatile organic compound emission profiles for each biomass-boiler combination. More than 100 types of volatile organic compounds(VOCs) were measured from the two biomass boilers. The measured VOC species included alkanes, alkenes and acetylenes, aromatics, halocarbons and carbonyls. A single coal-fired boiler(CB) was also studied to provide a basis for comparison. Biomass boiler 1(BB1) emitted relatively high proportions of alkanes(28.9%–38.1% by mass) and alkenes and acetylenes(23.4%–40.8%),while biomass boiler 2(BB2) emitted relatively high proportions of aromatics(27.9%–29.2%)and oxygenated VOCs(33.0%–44.8%). The total VOC(TVOC) emission factors from BB1(128.59–146.16 mg/kg) were higher than those from BB2(41.26–85.29 mg/kg). The total ozone formation potential(OFP) ranged from 6.26 to 81.75 mg/m^3 with an average of 33.66 mg/m^3 for the two biomass boilers. The total secondary organic aerosol potential(SOAP) ranged from 61.56 to 211.67 mg/m^3 with an average of 142.27 mg/m^3 for the two biomass boilers.The emission factors(EFs) of TVOCs from biomass boilers in this study were similar to those for industrial coal-fired boilers with the same thermal power. These data can supplement existing VOC emission factors for biomass combustion and thus enrich the VOC emission inventory.
基金supported by the National Natural Science Foundation of China (41161140352, 41471092)
文摘Human-environment relationship is a focus of academic researches and an understanding of the rela- tionship is important for making effective policies and decisions. In this study, based on rural household survey data of Taibus Banner, Duolun county and Zhengxiangbai Banner in the Inner Mongolia autonomous region of China, we identified the impact of livelihood diversification on ecosystems in these agro-pastoral areas by using the ecological footprint theory and methodology together with the one-way analysis of variance （ANOVA） and correlation analysis methods. In 2011, the total ecological footprint of consumption （EFC） was 0.665 g hm2, and the total ecological footprint of production （EFP） was 2.045 g hm2, which was more than three times the EFC. The ecological footprint of arable land consumption （EFAC） accounted for a large proportion of the EFC, and the ecological footprint of grassland production （EFGP） occupied a large proportion of the EFP. Both the ecological footprint of grassland consumption （EFGC） and EFGP had a significant positive correlation with the income, indicating that income was mainly depended on livestock production and the households with higher incomes consumed more livestock prod- ucts. The full-time farming households （FTFHs） had the highest EFP, ecological footprint of arable land production （EFAP）, EFGP and EFGC, followed by the part-time farming households （PTFHs） and non-farming households （NFHs）, which indicated that part-time farming and non-farming employment reduced the occupancy and con- sumption of rural households on local ecosystems and natural resources to some extent. When farming households engaged in livestock rearing, both the EFAP and EFAC became smaller, while the EFP, EFC, EFGC and EFGP increased significantly. The differences in ecological footprints among different household groups should be taken into account when making ecosystem conservation policies. Encouraging the laborers who have the advantages of participating in non-farming employment to move out of the rural areas and increasing the diversification of liveli- hoods of rural households are important in reducing the environmental pressures and improving the welfare of households in the study area. Moreover, grassland should be utilized more effectively in the future.
基金supported by the National Natural Science Foundation of China (Nos. 41530643, 41673130 and 41877393)the National Key R&D Program of China (No. 2017YFD0800301)the Chinese Academy of Sciences (No. QYZDJ-SSW-DQC038)
文摘It is well known that calcium arsenates may not be a good choice for arsenic removal and immobilization in hydrometallurgical practices.However,they are still produced at some plants in the world due to various reasons.Furthermore,calcium arsenates can also naturally precipitate under some specific environments.However,the transformation process of poorly crystalline calcium arsenates(PCCA)and the stability of these samples under atmospheric CO2 are not yet well understood.This work investigated the transformation process of PCCA produced by using different neutralization reagents(CaO vs.NaOH)with various Ca/As molar ratios at pH 7-12 in the presence of atmospheric CO2.After aging at room temperature for a period of time,for samples neutralized with NaOH and precipitated at pH 10 and 12,release of arsenic back into the liquid phase occurred.In contrast,for the samples precipitated at pH 8,the aqueous concentration of arsenic was observed to decrease.XRD,Raman,and SEM results suggested that the formation of various types of crystalline calcium carbonates and/or calcium arsenates controls the arsenic behavior.Moreover,the application of lime may enhance the stability of the generated PCCA.However,no matter what neutralization reagent is used,the stability of the generated PCCA is still of concern.
基金supported by the R&D Program of Beijing Municipal Education Commission(No.KJZD20191443001)the Project of Beijing Municipal Science&Technology Commission(No.Z181100000118003)the Foundation of Beijing Municipal Research Institute of Environmental Protection(No.Y2020-011)。
文摘Volatile organic compounds(VOCs)play an important role in the formation of ground-level ozone and secondary organic aerosol(SOA),and they have been key issues in current air pollution prevention and control in China.Considerable attention has been paid to industrial activities due to their large and relatively complex VOCs emissions.The present research aims to provide a comprehensive review on whole-process control of industrial VOCs,which mainly includes source reduction,collection enhancement and end-pipe treatments.Lower VOCs materials including water-borne ones are the keys to source substitution in industries related to coating and solvent usage,leak detection and repair(LDAR)should be regarded as an efficient means of source reduction in refining,petrochemical and other chemical industries.Several types of VOCs collection methods such as gas-collecting hoods,airtight partitions and others are discussed,and airtight collection at negative pressure yields the best collection efficiency.Current end-pipe treatments like UV oxidation,low-temperature plasma,activated carbon adsorption,combustion,biodegradation,and adsorption-combustion are discussed in detail.Finally,several recommendations are made for future advanced treatment and policy development in industrial VOCs emission control.
基金Supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2012BAC13B05)Science and Technology Foundation of Beijing Municipal Research Institute of Environmental Protection(No.2013B05)
文摘Allelopathic effects of submerged macrophytes against algae are affected by many environmental factors which can only be measured one by one by traditional methods. Box-Behnken design of response surface methodology was used to optimize three environmental factors （temperature, light intensity and total dissolved solids） of allelopathic effects of Potarnogeton pectinatus against Microcystis aeruginosa at the same time. By solving the regression equation and analyzing the response surface contour plots, the optimal conditions of the relatively inhibitory rate of Microcystis aeruginosa were that the temperature was 23℃, the light intensity was 2 700 lx and the total dissolved solids were 4 415 mg/L. Under these conditions, the optimal value of relatively inhibitory rate of Microcystis aeruginosa was 81.9%. According to validation experiments, the results of analysis indicated that the experimental values fitted well with the predicted ones.
基金supported by the National Natural Science Foundation of China(41701209,41501095,41601198)
文摘The carbon cycle of forest ecosystems plays a key role in regulating CO2 concentrations in the atmosphere. Research on carbon storage estimation of forest ecosystems has become a major research topic. However, carbon budgets of subtropical forest ecosystems have received little attention. Reports of soil carbon storage and topographic heterogeneity of carbon storage are limited. This study focused on the Jinggang Mountain National Nature Reserve as an example of a mid-subtropical forest and evaluated soil and vegetation carbon storage by field sampling combined with GIS, RS and GPS technology. We classified the forest into nine forest types using ALOS high-resolution remote sensing images. The evergreen broad-leaved forest has the largest area, occupying 26.5% of the total area, followed by coniferous and broad-leaved mixed forests and warm temperate coniferous forest, occupying 24.2 and 22.9%, respectively. The vegetation and soil carbon storage of the whole forest ecosystem were 1,692,344 and 5,514,707 t, with a carbon density of 7.4 and 24.2 kg/m^2, respectively, which suggests that the ecosystem has great carbon storage capacity. The topographic heterogeneity of the carbon storage was also analysed. The largest vegetation storage and soil storage is at 700–800 and 1000–1100 m, respectively. The vegetation carbon storage is highest in the southeast, south and southwest.
基金funded by the National Natural Science Foundation of China (Nos. 21377012, 21177012, 40975061)the National Science and Technology Support Programme of the Ministry of Science and Technology of China (Nos.2014BAC23B02, 2014BAC06B05)the Special Programme on Public Welfare of the Ministry of Environmental Protection (No. 201409022)
文摘The mass concentration and major chemical components of fine particulate matter were measured before,during and after Beijing＇s massive parade commemorating 70th anniversary of the Chinese Victory in World War II on September 3,2015.Regional emission inventory,positive matrix factorization（PMF）,observations from space and backward air mass trajectories were jointly applied to identify the major pollution sources and their temporal and spatial variations.The contributions of emissions variations and the meteorological conditions related to the＂parade blue＂phenomenon in Beijing and its surrounding areas were investigated in detail.The main cause of the decreased PM（2.5）mass concentration was attributed to the absolute reduction in emissions of primary air pollutants.The chemical composition of PM（2.5）varied significantly before,during and after the parade.Fugitive dust particles were well controlled,the secondary formation of PM（2.5）was reduced along with the controlled gaseous precursors＇emissions from vehicles and industrial sources during the temporary intensified control period.During the parade period,the SO2and NO2column concentrations in Beijing and the surrounding areas decreased sharply,indicating that the coordinated reduction in primary emissions from the surrounding areas of Beijing played an important role in lowering the ambient concentration of SO2and NO2and accordingly lowered PM（2.5）and improved the regional air quality.A comparison of the temperature,humidity,and wind speed and direction during the same periods in 2014 and 2015 showed that the meteorological conditions positively influenced the achievement of＂parade blue＂.
基金supported by the National Natural Science Foundation of China(No.21677177)Science Foundation of China University of Petroleum-Beijing(No.2462020XKJS04)。
文摘Organochlorine pesticides(OCPs)have received much attention due to their toxicity.Reliable methods to monitor their residues in the environment are needed.Here,magnetic polyamidoamine dendrimers were prepared by co-precipitation,Michael addition,and amidation.The magnetic polyamidoamine dendrimers demonstrated good adsorption ability for OCPs—this feature was utilized to construct a sensitive tool for monitoring OCPs in water samples.The proposed method provided remarkable linearity from 0.1 to 500μg/L and satisfactory limits of detection from 0.012 to 0.029μg/L.The spiked recoveries of the four target analytes were 91.8%-103.5%with relative standard deviations less than 4.5%.The magnetic materials had good reusability.The results indicated that the resulting method was an efficient,easy,rapid,economical,and eco-friendly tool for monitoring OCPs in aqueous samples.
基金supported by the National Science-Technology Support Plan Projects(2012BAC19B02)the Beijing Natural Science Foundation Projects(8154046)
文摘Anatomical characteristics have been proven useful for extracting climatic signals. To examine the climatic signals recorded by tree-ring cell features in the Changbai Mountains, we measured cell number and cell lumen diameter, in addition to ring widths, of Korean pine （Pinus koraiensis） tree rings at sites of varied elevation, and we developed chronologies of cell number （CN）, mean lumen diameter （MLD）, maximum lumen diameter （MAXLD） and tree-ring width （TRW）. The chronologies were correlated with climatic factors monthly mean tem- perature and the sum of precipitation. As shown by our analysis, the cell parameter chronologies were suitable for dendroclimatology studies. CN and TRW shared relatively similar climatic signals which differed from MLD and MAXLD, and growth-climate relationships were elevation- dependent, as shown by the following findings： （1） at each elevation, MLD and MAXLD recorded different monthly climatic signals from those recorded by TRW for the same climatic factors; and （2） MLD and MAXLD recorded cli- matic factors that were absent middle elevations. Cell lumen effective archive for improving for this study area. from TRW at lower and diameter proved to be an the climate reconstruction
文摘This paper aims to identify the main driving force for changes of total primary energy consumption in Beijing during the period of 1981-2005.Sectoral energy use was investigated when regional economic structure changed significantly.The changes of total primary energy consumption in Beijing are decomposed into production effects,structural effects and intensity effects using the additive version of the logarithmic mean Divisia index (LMDI) method.Aggregate decomposition analysis showed that the major contributor of total effect was made by the production effect fol- lowed by the intensity effect,and the structural effect was rela- tively insignificant.The total and production effects were all posi- tive.In contrast,the structural effect and intensity effect were all negative.Sectoral decomposition investigation indicated that the most effective way to slow down the growth rate of total primary energy consumption (TPEC) was to reduce the production of the energy-intensive industrial sectors and improving industrial en- ergy intensity.The results show that in this period,Beijing's economy has undergone a transformation from an industrial to a service economy.However,the structures of sectoral energy use have not been changed yet,and energy demand should be in- creasing until the energy-intensive industrial production to be reduced and energy intensity of the region reaches a peak.As sequence energy consumption data of sub-sectors are not available, only the fundamental three sectors are considered:agriculture, industry and service.However,further decomposition into secon- dary and tertiary sectors is definitely needed for detailed investi- gations.
基金supported by the Key project for Beijing Municipal Science and Technology Plan (No. D131100003613002)the Open Project from Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control of Nanjing University of Information Science and Technology (KHK1108)the Jiangsu Province Innovation Platform for Superiority Subject of Environmental Science and Engineering
文摘Particles from ambient air and combustion sources including vehicle emission, coal combustion and biomass burning were collected and chemically pretreated with the purpose of obtaining isolated BC（black carbon） samples. TEM（transmission electron microscopy）results indicate that BC from combustion sources shows various patterns, and airborne BC appears spherical and about 50 nm in diameter with a homogeneous surface and turbostratic structure. The BET（Barrett-Emmett-Teller） results suggest that the surface areas of these BC particles fall in the range of 3-23 m2/g, with a total pore volume of 0.03-0.05 cm3/g and a mean pore diameter of 7-53 nm. The nitrogen adsorption-desorption isotherms are indicative of the accumulation mode and uniform pore size. O2-TPO（temperature programmed oxidation）profiles suggest that the airborne BC oxidation could be classified as the oxidation of amorphous carbon, which falls in the range of 406-490℃ with peaks at 418, 423 and 475℃,respectively. Generally, the BC characteristics and source analysis suggest that airborne BC most likely comes from diesel vehicle emission at this site.
基金supported by the National Natural Science Foundation of China (No.21806012)Beijing Municipal Science and Technology Project (No.Z181100005418015)
文摘Over the past decade,the emission standards and fuel standards in Beijing have been upgraded twice,and the vehicle structure has been improved by accelerating the elimination of 2.95 million old vehicles.Through the formulation and implementation of these policies,the emissions of carbon monoxide(CO),volatile organic compounds(VOCs),nitrogen oxides(NO_(x)),and fine particulate matter(PM_(2.5))in 2019 were 147.9,25.3,43.4,and 0.91 kton in Beijing,respectively.The emission factor method was adopted to better understand the emissions characteristics of primary air pollutants from combustion engine vehicles and to improve pollution control.In combination with the air quality improvement goals and the status of social and economic development during the 14th Five-Year Plan period in Beijing,different vehicle pollution control scenarios were established,and emissions reductions were projected.The results show that the emissions of four air pollutants(CO,VOCs,NO_(x),and PM_(2.5))fromvehicles in Beijing decreased by an average of 68% in 2019,compared to their levels in 2009.The contribution of NOx emissions from diesel vehicles increased from 35% in 2009 to 56% in 2019,which indicated that clean and energy-saving diesel vehicle fleets should be further improved.Electric vehicle adoption could be an important measure to reduce pollutant emissions.With the further upgrading of vehicle structure and the adoption of electric vehicles,it is expected that the total emissions of the four vehicle pollutants can be reduced by 20%-41% by the end of the 14th Five-Year Plan period.
基金Fujian Province Natural Science Foundation of China(No.2017J01673)
文摘The influences of additives of NH_3,HCl,KOH and CH_3OH on the solvothermal synthesis of the Zn-based metal-organic frameworks(Zn-MOF_5s)were investigated.Powder X-ray diffraction(PXRD),thermal gravimetric analysis(TGA),Fourier translation infrared spectroscope(FT-IR),N_2adsorption/desorption at 77 K and CO_2sorption measurements were used to characterize the as-prepared Zn-MOF_5s.The experimental results showthat additives of NH_3,CH_3OH,HCl and KOH in the synthesis of the Zn-MOF_5s do not change the underlying topology,but they are extremely sensitive to the pore textural properties,thus changing the CO_2adsorption capacity.Additives would lower the pore width and the surface area,and then lower the CO_2adsorption capacity of Zn-MOF_5s.
基金supported by the Open Research Fund Program of State Environmental Protection Key Laboratory of Food Chain Pollution Control(No.FC2021YB03)the Research Foundation for Youth Scholars of Beijing Technology and Business University(No.QNJJ2021-32).
文摘Cooking process can produce abundant volatile organic compounds(VOCs),which are harmful to environment and human health.Therefore,we conducted a comprehensive analysis in which VOCs emissions from multiple cuisines have been sampled based on the simulation and acquisition platform,involving concentration characteristics,ozone formation potential(OFP)and purification efficiency assessments.VOCs emissions varied from 1828.5 to 14,355.1μg/m^(3),with the maximumand minimumvalues fromBarbecue and Family cuisine,respectively.Alkanes and alcohol had higher contributions to VOCs from Sichuan and Hunan cuisine(64.1%),Family cuisine(66.3%),Shandong cuisine(69.1%)and Cantonese cuisine(69.8%),with the dominant VOCs species of ethanol,isobutane and n-butane.In comparison,alcohols(79.5%)were abundant for Huaiyang cuisine,while alkanes(19.7%),alkenes(35.9%)and haloalkanes(22.9%)accounted for higher proportions from Barbecue.Specially,carbon tetrachloride,n-hexylene and 1-butene were the most abundant VOCs species for Barbecue,ranging from 8.8%to 14.6%.The highest OFP occurred in Barbecue.The sensitive species of OFP for Huaiyang cuisine were alcohols,while other cuisines were alkenes.Purification efficiency assessments shed light on the removal differences of individual and synergistic control technologies.VOCs emissions exhibited a strong dependence on the photocatalytic oxidation,with the removal efficiencies of 29.0%–54.4%.However,the high voltage electrostatic,wet purification and mechanical separation techniques played a mediocre or even counterproductive role in the VOCs reduction,meanwhile collaborative control technologies could not significantly improve the removal efficiency.Our results identifiedmore effective control technologies,which were conductive to alleviating air pollution from cooking emissions.
