The composition of products formed from photooxidation of the aromatic hydrocarbon toluene was investigated. The OH-initiated photooxidation experiments were conducted by irradiating toluene/CH3ONO/NO/air mixtures in ...The composition of products formed from photooxidation of the aromatic hydrocarbon toluene was investigated. The OH-initiated photooxidation experiments were conducted by irradiating toluene/CH3ONO/NO/air mixtures in a smog chamber, the gaseous products were detected under the supersonic beam conditions by utilizing vacuum ultraviolet photoionization mass spectrometer using synchrotron radiation in real-time. And an aerosol time-of-flight mass spectrometer was used to provide on-line measurements of the individual secondary organic aerosol particle resulting from irradiating toluene. The experimental results demonstrated that there were some differences between the gaseous products and that of particle-phase, the products of glyoxal, 2-hydroxyl-3-oxo-butanal, nitrotoluene, and methyl-nitrophenol only existed in the particle-phase. However, furane, methylglyoxal, 2-methylfurane, benzaldehyde, cresol, and benzoic acid were the predominant photooxidation products in both the gas phase and particle phase.展开更多
In order to explore the fertilizing ways and dynamic changes of soil carbon and nitrogen in the main producing areas of tobacco in Guizhou,research was conducted to study the variations of dissolved organic carbon and...In order to explore the fertilizing ways and dynamic changes of soil carbon and nitrogen in the main producing areas of tobacco in Guizhou,research was conducted to study the variations of dissolved organic carbon and nitrogen,total organic carbon and nitrogen and their ratio of tobacco-topsoil in organic fertilization pattern and conventional cultivation pattern (No fertilizer as control) by pot experiment.The results were as follows:(1) The effects of different fertilization patterns on soil dissolved organic carbon and nitrogen and total organic carbon and nitrogen were significantly different.The content of DOC,DON,TOC and TON in tobaccotopsoil was decreased with the advancing of growth period in conventional fertilization pattern.In the conventional fertilization pattern,the accumulation of DOC and TOC was increased first and then decreased,and the accumulation of DON and TON was decreased first and then increased.(2) The TOC content at the different growing stage and DOC content at the middle and later stage of tobacco were significantly improved in organic fertilization patterns.The accumulation of DON and TON in the conventional fertilization pattern was significantly higher than those in the organic fertilizer pattern and control at the rosette stage and vigorous stage.In the harvest period,the content of DOC,DON,TOC and TON of tobacco-topsoil in the conventional fertilization and organic fertilization pattern was significantly higher than those in the control.(3)The DOC/DON ratio and the TOC/TiON ratio was increased gradually with the advancing of growth period in conventional fertilization pattern,but they were increased first and then decreased in the organic fertilization pattern and CK.The DOC/DON and TOC/TON ratio of tobacco-topsoil in different fertilization patterns was showed as Y J> CK> CG at the different growing stage.The experiment results revealed that:The organic fertilization pattern may improve significantly the accumulation of DOC,DON,TOC and TON of tobacco-topsoil at the middle and later stage and the DOC/DON and TOC/TON ratio at the different growth stage.It contributed to the continuous and balanced supply of nutrients at the middle and later stage of tobacco and the soil fertility.展开更多
This study aimed to investigate the application effect of analog water-soluble fertilizer as an alternative of flue-cured tobacco-specific topdressing fertilizer. A field experiment was conducted, and the dry matter a...This study aimed to investigate the application effect of analog water-soluble fertilizer as an alternative of flue-cured tobacco-specific topdressing fertilizer. A field experiment was conducted, and the dry matter accumulation, intrinsic chemical composition, smoking quality and economic benefit of flue-cured tobacco were compared between analog water-soluble fertilizer and conventional fertilizer, The results showed compared with conventional fertilizer, analog water-soluble fertilizer increased the dry matter accumulation in flue-cured tobacco by 4.90%-16.70%, increased the yield of flue-cured tobacco by 6%-15%, and increased the output of flue-cured tobacco by 5%-14%. In terms of chemical composition, the flue-cured tobacco applied with analog water-soluble fertilizer was better than that applied with conventional fertilizer, except the nicotine content in the upper leaves, the potassium content in the middle leaves and the reducing sugar content. The smoking quality of both the upper and middle leaves of flue-cured tobacco in the analog water-soluble fertilizer treatment groups was better than that in the conventional fertilizer treatment group. In short, analog water-soluble fertilizer was better than conventional fertilizer, with advantages of lower cost (reduced by 381.60 yuan/hm2), lower application amount (reduced by 165 kg/hm2) and higher utilization efficiency.展开更多
The influence of various water soluble cations(K^+,Na^+,Ca^2+,Mg^2+)on the hydration of calcined flue gas desulphurization gypsum was investigated.The results show that all cations but Ca^2+can accelerate the hydratio...The influence of various water soluble cations(K^+,Na^+,Ca^2+,Mg^2+)on the hydration of calcined flue gas desulphurization gypsum was investigated.The results show that all cations but Ca^2+can accelerate the hydration of bassanite.The final crystal size is not largely influenced by different salts,except for Na^+,where the giant crystal with length of>130μm is observed.Current study clarifies the influence of different ions on the hydration of bassanite,which could provide sufficient guide for the pre-treatment of original flue gas desulphurization gypsum before actual application.展开更多
The mechanism of all present adopted desulfurization technologies is chemical reaction. A new kind of desulfurization medium - TiO 2 particle having large fraction void and specific surface area which is made from Ti...The mechanism of all present adopted desulfurization technologies is chemical reaction. A new kind of desulfurization medium - TiO 2 particle having large fraction void and specific surface area which is made from TiO 2 with superfine size sintered at low temperature and processed with surface activation is tested and investigated. The mechanism of desulfurization is mainly physical adsorption instead of traditional chemical reaction. Four samples of such TiO 2 particles were characterized by advanced instruments and tested for adsorption dynamics at the temperature range of 90?℃ to 240?℃ in a fixed bed. The results show that its adsorption ability for SO 2in flue gas is dependent strongly on three factors: quality of TiO 2particles, adsorption temperature and SO 2 concentration in flue gas. Titanium dioxide has well desulfurization character and pretty good prospect in engineering application. Sintered at temperature range from 440?℃ to 540?℃, it has the best adsorption ability. In practical use the best adsorption temperature is around 120?℃.展开更多
Deep eutectic solvents(DESs) are a kind of potential lixiviant for selective metal processing due to their versatile complexation properties. In this study, we investigated the recovery of zinc from zinc oxide dust us...Deep eutectic solvents(DESs) are a kind of potential lixiviant for selective metal processing due to their versatile complexation properties. In this study, we investigated the recovery of zinc from zinc oxide dust using choline chloride-ureaethylene glycol(ChCl-urea-EG) DESs. The zinc extraction efficiency can be up to 85.2% when the slurry concentration is 50 g/L, leaching temperature is 80 °C and stirring speed is 600 r/min. The leaching process is controlled by the diffusion and the corresponding activation energy is 32.1 k J/mol. The resultant solution was directly used for the electrodeposition of zinc. The pure zinc deposit is obtained with a current efficiency of 82.6%. Furthermore, the ChCl-urea-EG DESs can be recycled. This approach is shown to be promising for the recycling of zinc from the zinc-containing dust.展开更多
A series of three‐dimensionally ordered macroporous(3DOM)SnO2‐based catalysts modified by the cations Ce4+,Mn3+,and Cu2+have been prepared by using a colloidal crystal templating method and tested for soot combustio...A series of three‐dimensionally ordered macroporous(3DOM)SnO2‐based catalysts modified by the cations Ce4+,Mn3+,and Cu2+have been prepared by using a colloidal crystal templating method and tested for soot combustion under loose contact condition.XRD and STEM mapping results confirm that all the secondary metal cations have entered the lattice matrix of tetragonal rutile SnO2 to form non‐continuous solid solutions,thus impeding crystallization and improving the surface areas and pore volumes of the modified catalysts.In comparison with regular SnO2 nanoparticles,the 3DOM SnO2 displays evidently improved activity,testifying that the formation of the 3DOM structure can anchor the soot particulates in the macro‐pores,which ensures that the contact of the soot particles with the active sites on the 3DOM skeleton is more easily formed,thus benefiting the target reaction.With the incorporation of the secondary metal cations,the activity of the catalyst can be further improved due to the formation of more abundant mobile oxygen species.In summary,these effects are believed to be the major factors responsible for the activity of the catalyst.展开更多
Environmental issue has concerned the public with the build-up of soil phosphorus(P) following application of organic manure.This demands a fully understanding of the change of phosphorus during composting of fresh wa...Environmental issue has concerned the public with the build-up of soil phosphorus(P) following application of organic manure.This demands a fully understanding of the change of phosphorus during composting of fresh waste leaves of tobacco and finding out the status of P fertilizer in leaf-made manure.This study had shown that water-soluble and HCl-soluble phosphon were the dominant fractions of P in the compost of fresh waste leaves,in the ranges of 19%-41% and 17%-43%,respectively.However,the former declined progressively upon composting time,but the latter increased,indicating transformation of the more vulnerable water soluble P to the more recalcitrant HCl-extractable P.展开更多
Direct phase transformation of flue gas desulfurization gypsum in hot salt solution at atmospheric pres-sure was investigated.The effects of temperature,salt species,salt concentration,solids content,pH and modifier w...Direct phase transformation of flue gas desulfurization gypsum in hot salt solution at atmospheric pres-sure was investigated.The effects of temperature,salt species,salt concentration,solids content,pH and modifier were examined.The crystals obtained under different conditions and solubility of calcium sulfate in contact with solid gypsum were also determined.α-Calcium sulfate hemihydrate crystals of stubby columnar shape and regular pentahedral sides were obtained under the following conditions:salt concentration 20%-30%,operation tempera-ture 95-100 °C,solids mass content in the slurry 10%-30% and neutral pH.Thermodynamic analysis revealed that phase transformation of calcium sulfate dihydrate to α-calcium sulfate hemihydrate occurs because of the difference in solubilities between the two solid gypsum phases in this system.展开更多
The objectives of this work are to study the primary chemical structure of soot aerosol derived from lump-coal combustion in different experimental conditions in fixed bed. A laboratory-scale movable fixed bed, water-...The objectives of this work are to study the primary chemical structure of soot aerosol derived from lump-coal combustion in different experimental conditions in fixed bed. A laboratory-scale movable fixed bed, water-cooled soot aerosol collection system, and electric reactor have been designed and used in the process. Three kinds of coals, sized at 3-5 ram, have been heated in the experiments. Fourier Transform Infrared Spectroscopy (FTlR) has been employed to test functional groups of soot aerosol samples. Infrared spectra from 400 to 4000 cm^ -1 and semiquantitative analysis have been employed. The results of experiments show that contents of hydrogen-bonded are increased, contents of unsaturated hydrocarbons are increased, and contents of aromatic hydrocarbons are decreased with temperature increase; contents of hydrogen-bonded and unsaturated hydrocarbons are increased first and decreased late, and contents of aromatic hydrocarbons are decreased with gases residence time extension; the contents of hydrogen bonded and unsaturated hydrocarbons derived from soot aerosol samples are higher than those from original coal samples in lower-volatile coals, and the contents of aromatic hydrocarbons derived from soot aerosol samples are lower than those from original coals; and contents of hydrogen-bonded are decreased, contents of unsaturated hydrocarbons are increased, and contents of aromatic hydrocarbons are decreased with a increase.展开更多
Black carbon (BC) aerosol, accounting for a minor fraction of atmospheric aerosols, is attracting increased attentio1 due to its impact on air quality, human health, and climate change. Focusing on BC emission reduc...Black carbon (BC) aerosol, accounting for a minor fraction of atmospheric aerosols, is attracting increased attentio1 due to its impact on air quality, human health, and climate change. Focusing on BC emission reduction, this paper give1 a brief introduction to the sources and global distribution of BC. Along with the decrease of BC emissions from sue1 actions as the reduction of global greenhouse gases (GHGs) and regulating local air quality, it also highlights othet BC reduction approaches such as control and improvement of combustion conditions, the elimination of open biomas burning, and the sequestration of BC by biomass pyrolysis. Finally, it is stressed that at this moment there is no enougt reason to push BC reduction into any climate change related negotiations, although BC has been included in some o so-called win-win reduction targets for the quick response to both climate and non-climate appeals.展开更多
The present work is concerned with the voltammetric application of unmodified tricresyl phosphate carbon paste electrode (TCP-CPE) and in situ bismuth-film modified tricresyl phosphate-based carbon paste electrode ...The present work is concerned with the voltammetric application of unmodified tricresyl phosphate carbon paste electrode (TCP-CPE) and in situ bismuth-film modified tricresyl phosphate-based carbon paste electrode (BiF-TCP-CPE). The TCP-CPE was examined with the main objective of using it for the differential pulse voltammetric analysis of some neonicotinoid insecticides in aqueous Britton-Robinson buffer solution pH 7.0 as supporting electrolyte. After comparing the performance of the TCP-CPE with that of silicone oil carbon paste electrode, quantitative analysis of imidacloprid, thiamethoxam and clothianidin was performed in model solutions and real samples (river water and commercial insecticide formulations). The in situ prepared BiF-TCP-CPE was tested for a simultaneous detection of selected heavy metal ions (Cd^2+ and Pb^2+) at a μg/dm^3 concentration level, using square wave anodic stripping voltammetric technique. The influence of different electrochemical pretreatments of the working electrode on the bismuth deposition and analyte signals were investigated. Film formation was studied at untreated, pre-cathodized and pre-anodized TCP-CPEs in the acetic buffer solution pH 4.6, containing 1 μg/cm^3 Bi (III).展开更多
基金This work was supported by the Open Research Fund of Key Laboratory of Atmospheric Composition and Optical Radiation, Chinese Academy of Sciences (No.J J-10-04), Knowledge Innovation Foundation of Chinese Academy of Sciences (KJCX2-YW-N24), and the National Natural Science Foundation of China (No.40975080 and No.10979061).
文摘The composition of products formed from photooxidation of the aromatic hydrocarbon toluene was investigated. The OH-initiated photooxidation experiments were conducted by irradiating toluene/CH3ONO/NO/air mixtures in a smog chamber, the gaseous products were detected under the supersonic beam conditions by utilizing vacuum ultraviolet photoionization mass spectrometer using synchrotron radiation in real-time. And an aerosol time-of-flight mass spectrometer was used to provide on-line measurements of the individual secondary organic aerosol particle resulting from irradiating toluene. The experimental results demonstrated that there were some differences between the gaseous products and that of particle-phase, the products of glyoxal, 2-hydroxyl-3-oxo-butanal, nitrotoluene, and methyl-nitrophenol only existed in the particle-phase. However, furane, methylglyoxal, 2-methylfurane, benzaldehyde, cresol, and benzoic acid were the predominant photooxidation products in both the gas phase and particle phase.
基金Supported by The General Program of National Natural Science Foundation of China(312771673)Programs for Science and Technology Development of Tobacco Monopoly Bureau in Guizhou Province(20121126)~~
文摘In order to explore the fertilizing ways and dynamic changes of soil carbon and nitrogen in the main producing areas of tobacco in Guizhou,research was conducted to study the variations of dissolved organic carbon and nitrogen,total organic carbon and nitrogen and their ratio of tobacco-topsoil in organic fertilization pattern and conventional cultivation pattern (No fertilizer as control) by pot experiment.The results were as follows:(1) The effects of different fertilization patterns on soil dissolved organic carbon and nitrogen and total organic carbon and nitrogen were significantly different.The content of DOC,DON,TOC and TON in tobaccotopsoil was decreased with the advancing of growth period in conventional fertilization pattern.In the conventional fertilization pattern,the accumulation of DOC and TOC was increased first and then decreased,and the accumulation of DON and TON was decreased first and then increased.(2) The TOC content at the different growing stage and DOC content at the middle and later stage of tobacco were significantly improved in organic fertilization patterns.The accumulation of DON and TON in the conventional fertilization pattern was significantly higher than those in the organic fertilizer pattern and control at the rosette stage and vigorous stage.In the harvest period,the content of DOC,DON,TOC and TON of tobacco-topsoil in the conventional fertilization and organic fertilization pattern was significantly higher than those in the control.(3)The DOC/DON ratio and the TOC/TiON ratio was increased gradually with the advancing of growth period in conventional fertilization pattern,but they were increased first and then decreased in the organic fertilization pattern and CK.The DOC/DON and TOC/TON ratio of tobacco-topsoil in different fertilization patterns was showed as Y J> CK> CG at the different growing stage.The experiment results revealed that:The organic fertilization pattern may improve significantly the accumulation of DOC,DON,TOC and TON of tobacco-topsoil at the middle and later stage and the DOC/DON and TOC/TON ratio at the different growth stage.It contributed to the continuous and balanced supply of nutrients at the middle and later stage of tobacco and the soil fertility.
基金Supported by Support Project of Guizhou Branch of China Tobacco Corporation(2015-07)~~
文摘This study aimed to investigate the application effect of analog water-soluble fertilizer as an alternative of flue-cured tobacco-specific topdressing fertilizer. A field experiment was conducted, and the dry matter accumulation, intrinsic chemical composition, smoking quality and economic benefit of flue-cured tobacco were compared between analog water-soluble fertilizer and conventional fertilizer, The results showed compared with conventional fertilizer, analog water-soluble fertilizer increased the dry matter accumulation in flue-cured tobacco by 4.90%-16.70%, increased the yield of flue-cured tobacco by 6%-15%, and increased the output of flue-cured tobacco by 5%-14%. In terms of chemical composition, the flue-cured tobacco applied with analog water-soluble fertilizer was better than that applied with conventional fertilizer, except the nicotine content in the upper leaves, the potassium content in the middle leaves and the reducing sugar content. The smoking quality of both the upper and middle leaves of flue-cured tobacco in the analog water-soluble fertilizer treatment groups was better than that in the conventional fertilizer treatment group. In short, analog water-soluble fertilizer was better than conventional fertilizer, with advantages of lower cost (reduced by 381.60 yuan/hm2), lower application amount (reduced by 165 kg/hm2) and higher utilization efficiency.
基金supported by the National Natural Science Foundation of China(No.51473152)Scientific research foundation for Young Talents from Fujian Provincial Department of Education(No.JT180494)+2 种基金Start-up Foundation for Advanced Talents in Sanming University(No.18YG07)Industry-University-Research Cooperation Fund from Sanming Institute of Fluorine Chemical Industry Technology(FCIT20180105)Scientific research Platform Construction Pproject from Fujian Provincial Department of Science and Technology(No.2018H2002).
文摘The influence of various water soluble cations(K^+,Na^+,Ca^2+,Mg^2+)on the hydration of calcined flue gas desulphurization gypsum was investigated.The results show that all cations but Ca^2+can accelerate the hydration of bassanite.The final crystal size is not largely influenced by different salts,except for Na^+,where the giant crystal with length of>130μm is observed.Current study clarifies the influence of different ions on the hydration of bassanite,which could provide sufficient guide for the pre-treatment of original flue gas desulphurization gypsum before actual application.
文摘The mechanism of all present adopted desulfurization technologies is chemical reaction. A new kind of desulfurization medium - TiO 2 particle having large fraction void and specific surface area which is made from TiO 2 with superfine size sintered at low temperature and processed with surface activation is tested and investigated. The mechanism of desulfurization is mainly physical adsorption instead of traditional chemical reaction. Four samples of such TiO 2 particles were characterized by advanced instruments and tested for adsorption dynamics at the temperature range of 90?℃ to 240?℃ in a fixed bed. The results show that its adsorption ability for SO 2in flue gas is dependent strongly on three factors: quality of TiO 2particles, adsorption temperature and SO 2 concentration in flue gas. Titanium dioxide has well desulfurization character and pretty good prospect in engineering application. Sintered at temperature range from 440?℃ to 540?℃, it has the best adsorption ability. In practical use the best adsorption temperature is around 120?℃.
基金Project(51764027) supported by the National Natural Science Foundation of ChinaProject(2014CB643404) supported by the National Basic Research Program of China
文摘Deep eutectic solvents(DESs) are a kind of potential lixiviant for selective metal processing due to their versatile complexation properties. In this study, we investigated the recovery of zinc from zinc oxide dust using choline chloride-ureaethylene glycol(ChCl-urea-EG) DESs. The zinc extraction efficiency can be up to 85.2% when the slurry concentration is 50 g/L, leaching temperature is 80 °C and stirring speed is 600 r/min. The leaching process is controlled by the diffusion and the corresponding activation energy is 32.1 k J/mol. The resultant solution was directly used for the electrodeposition of zinc. The pure zinc deposit is obtained with a current efficiency of 82.6%. Furthermore, the ChCl-urea-EG DESs can be recycled. This approach is shown to be promising for the recycling of zinc from the zinc-containing dust.
基金the Natural Science Foundation of China(21567016,21503106)the Natural Science Foundation of Jiangxi Province(20171BAB213013)+3 种基金the Education Department Foundation of Jiangxi Province(KJLD14005)National Key Research and Development Program of China(2016YFC0209302)the Innovation Fund Designated for Graduate Students of Jiangxi Province(YC2015-B017)the Innovation Fund Designated for Undergraduate Students of China(201701035)~~
文摘A series of three‐dimensionally ordered macroporous(3DOM)SnO2‐based catalysts modified by the cations Ce4+,Mn3+,and Cu2+have been prepared by using a colloidal crystal templating method and tested for soot combustion under loose contact condition.XRD and STEM mapping results confirm that all the secondary metal cations have entered the lattice matrix of tetragonal rutile SnO2 to form non‐continuous solid solutions,thus impeding crystallization and improving the surface areas and pore volumes of the modified catalysts.In comparison with regular SnO2 nanoparticles,the 3DOM SnO2 displays evidently improved activity,testifying that the formation of the 3DOM structure can anchor the soot particulates in the macro‐pores,which ensures that the contact of the soot particles with the active sites on the 3DOM skeleton is more easily formed,thus benefiting the target reaction.With the incorporation of the secondary metal cations,the activity of the catalyst can be further improved due to the formation of more abundant mobile oxygen species.In summary,these effects are believed to be the major factors responsible for the activity of the catalyst.
基金Supported by the Vega Waste Directional Fermentation Technology Research for Technical Improvement Project from China National Tobacco Corporation(Project code:20110410)Utilization and Technology Integration of Efficient Biological Fermentation on Tobacco Organic Waste Project from Henan Province Tobacco Corporation(Project code:HYKJ201215)
文摘Environmental issue has concerned the public with the build-up of soil phosphorus(P) following application of organic manure.This demands a fully understanding of the change of phosphorus during composting of fresh waste leaves of tobacco and finding out the status of P fertilizer in leaf-made manure.This study had shown that water-soluble and HCl-soluble phosphon were the dominant fractions of P in the compost of fresh waste leaves,in the ranges of 19%-41% and 17%-43%,respectively.However,the former declined progressively upon composting time,but the latter increased,indicating transformation of the more vulnerable water soluble P to the more recalcitrant HCl-extractable P.
基金Supported by the National High Technology Research and Development Program of China(2006AA06Z385) the Science Foundation of Wuhan University of Science and Technology(2008RC06)
文摘Direct phase transformation of flue gas desulfurization gypsum in hot salt solution at atmospheric pres-sure was investigated.The effects of temperature,salt species,salt concentration,solids content,pH and modifier were examined.The crystals obtained under different conditions and solubility of calcium sulfate in contact with solid gypsum were also determined.α-Calcium sulfate hemihydrate crystals of stubby columnar shape and regular pentahedral sides were obtained under the following conditions:salt concentration 20%-30%,operation tempera-ture 95-100 °C,solids mass content in the slurry 10%-30% and neutral pH.Thermodynamic analysis revealed that phase transformation of calcium sulfate dihydrate to α-calcium sulfate hemihydrate occurs because of the difference in solubilities between the two solid gypsum phases in this system.
文摘The objectives of this work are to study the primary chemical structure of soot aerosol derived from lump-coal combustion in different experimental conditions in fixed bed. A laboratory-scale movable fixed bed, water-cooled soot aerosol collection system, and electric reactor have been designed and used in the process. Three kinds of coals, sized at 3-5 ram, have been heated in the experiments. Fourier Transform Infrared Spectroscopy (FTlR) has been employed to test functional groups of soot aerosol samples. Infrared spectra from 400 to 4000 cm^ -1 and semiquantitative analysis have been employed. The results of experiments show that contents of hydrogen-bonded are increased, contents of unsaturated hydrocarbons are increased, and contents of aromatic hydrocarbons are decreased with temperature increase; contents of hydrogen-bonded and unsaturated hydrocarbons are increased first and decreased late, and contents of aromatic hydrocarbons are decreased with gases residence time extension; the contents of hydrogen bonded and unsaturated hydrocarbons derived from soot aerosol samples are higher than those from original coal samples in lower-volatile coals, and the contents of aromatic hydrocarbons derived from soot aerosol samples are lower than those from original coals; and contents of hydrogen-bonded are decreased, contents of unsaturated hydrocarbons are increased, and contents of aromatic hydrocarbons are decreased with a increase.
基金co-supported by China 973 project of MOST(2011CB403401)China Postdoctoral Science Foundation(20080440463,200902157)
文摘Black carbon (BC) aerosol, accounting for a minor fraction of atmospheric aerosols, is attracting increased attentio1 due to its impact on air quality, human health, and climate change. Focusing on BC emission reduction, this paper give1 a brief introduction to the sources and global distribution of BC. Along with the decrease of BC emissions from sue1 actions as the reduction of global greenhouse gases (GHGs) and regulating local air quality, it also highlights othet BC reduction approaches such as control and improvement of combustion conditions, the elimination of open biomas burning, and the sequestration of BC by biomass pyrolysis. Finally, it is stressed that at this moment there is no enougt reason to push BC reduction into any climate change related negotiations, although BC has been included in some o so-called win-win reduction targets for the quick response to both climate and non-climate appeals.
文摘The present work is concerned with the voltammetric application of unmodified tricresyl phosphate carbon paste electrode (TCP-CPE) and in situ bismuth-film modified tricresyl phosphate-based carbon paste electrode (BiF-TCP-CPE). The TCP-CPE was examined with the main objective of using it for the differential pulse voltammetric analysis of some neonicotinoid insecticides in aqueous Britton-Robinson buffer solution pH 7.0 as supporting electrolyte. After comparing the performance of the TCP-CPE with that of silicone oil carbon paste electrode, quantitative analysis of imidacloprid, thiamethoxam and clothianidin was performed in model solutions and real samples (river water and commercial insecticide formulations). The in situ prepared BiF-TCP-CPE was tested for a simultaneous detection of selected heavy metal ions (Cd^2+ and Pb^2+) at a μg/dm^3 concentration level, using square wave anodic stripping voltammetric technique. The influence of different electrochemical pretreatments of the working electrode on the bismuth deposition and analyte signals were investigated. Film formation was studied at untreated, pre-cathodized and pre-anodized TCP-CPEs in the acetic buffer solution pH 4.6, containing 1 μg/cm^3 Bi (III).