In response to the fact that the presence of manganese dithionate(MnS_(2)O_(6))leads to a series of adverse impacts,especially lower purity of manganese sulfate(MnSO_(4))and disruption of its recovery,advanced oxidati...In response to the fact that the presence of manganese dithionate(MnS_(2)O_(6))leads to a series of adverse impacts,especially lower purity of manganese sulfate(MnSO_(4))and disruption of its recovery,advanced oxidation methods such as ozonation system are used to manage MnS_(2)O_(6)in the leaching solution,replacing conventional methods.To ascertain the conversion rate and kinetics of MnS_(2)O_(6)during the ozonation process,we explored the factors influencing its removal rate,including ozone dosage,manganese dithionate concentration,sulfuric acid concentration,and reaction temperature.Batch experiments were conducted to determine the reaction rate constant of ozone(k)and activation energy(Ea)obtained from intermittent experimental data fitting,revealing a least-squares exponential conversion relationship between k and the MnS_(2)O_(6)removal amount,wherein an increase in the aforementioned factors led to an enhanced MnS_(2)O_(6)conversion rate,exceeding 99.3%.The formation mechanism of the ozone products proposed during the experiment was summarized and proposed as follows:1)Mn^(2+)was directly oxidized to MnO_(2),and 2)SO_(4)2−was obtained by the catalytic oxidation of S_(2)O_(6)^(2−)with HO•from O3 decomposition.According to the kinetics analysis,the pre-exponential factor and total activation energy of the ozonation kinetics equation were 1.0×10^(23) s^(−1) and 177.28 kJ/mol,respectively.Overall,the present study demonstrates that O_(3) as an oxidizing agent can effectively facilitate MnS_(2)O_(6)disproportionation while preventing the release of the secondary pollutant,SO_(2)gas.展开更多
A novel heterogeneous catalytic ozonation process in water treatment was studied, with a copper-loaded activated carbon （Cu/AC） that was prepared by an incipient wetness impregnation method at low temperature and te...A novel heterogeneous catalytic ozonation process in water treatment was studied, with a copper-loaded activated carbon （Cu/AC） that was prepared by an incipient wetness impregnation method at low temperature and tested as a catalyst in the ozonation of phenol and oxalic acid. Cu/AC was characterized using XRD, BET and SEM techniques. Compared with ozonation alone, the presence of Cu/AC in the ozonation processes significantly improves the degradation of phenol or oxalic acid. With the introduction of the hydroxyl radical scavenger, i.e., turt-butanol alcohol （t-BuOH）, the degradation efficiency of both phenol and oxalic acid in the Cu/AC catalyzed ozonation process decreases by 22% at 30 min. This indicates that Cu/AC accelerates ozone decomposition into certain concentration of hydroxyl radicals. The amount of Cu（II ） produced during the reaction of Cu/AC-catalyzed ozonation of phenol or oxalic acid is very small, which shows that the two processes are both heterogeneous catalytic ozonation reactions.展开更多
依托中国稻田臭氧FACE(Free Air ozone Concentration Enrichment)技术平台,以常规籼稻扬稻6号为供试材料,设置大气臭氧浓度(Ambient)和高臭氧浓度(比Ambient高50%),移栽密度设置低密度(16穴/m2)、中密度(24穴/m2)和高密度(32穴/m2),研...依托中国稻田臭氧FACE(Free Air ozone Concentration Enrichment)技术平台,以常规籼稻扬稻6号为供试材料,设置大气臭氧浓度(Ambient)和高臭氧浓度(比Ambient高50%),移栽密度设置低密度(16穴/m2)、中密度(24穴/m2)和高密度(32穴/m2),研究不同移栽密度下近地层臭氧浓度升高对水稻生长发育和产量的影响。结果表明,高浓度臭氧对水稻抽穗期、成熟期和最终株高均无显著影响,但使收获期生物产量显著下降,其中低、中和高密度条件下分别下降23%、20%和9%。臭氧胁迫导致的生物产量下降主要与拔节至抽穗期物质生产量明显下降有关(-23%),而营养生长期物质生产量差异不显著。前者主要与高浓度臭氧下水稻生长后期的净同化率(NAR)显著下降有关,也与该期叶面积指数(LAI)下降部分相关。高浓度臭氧对营养生长期不同器官生物量影响较小,但可使生殖生长期各器官生物量显著下降,其中茎鞘生物量降幅大于叶片,因此,臭氧胁迫下生物量在叶片中的分配比例呈增加趋势,而在茎鞘中的分配比例则相反。臭氧胁迫对单位面积穗数和每穗颖花数均无显著影响,但使饱粒率和饱粒重显著下降,空粒率和秕粒率明显增加。臭氧胁迫使水稻籽粒产量平均下降16%,其中,低、中、高密度下分别下降24%、14%和10%。臭氧胁迫对水稻生长后期的LAI、NAR、物质生产量以及每穗颖花数、饱粒重和籽粒产量的负面影响均随密度的增加而呈减小的趋势。以上结果表明,适当增加移栽密度可以减小臭氧胁迫对水稻生长后期的光合面积特别是净同化率的影响,进而减轻对颖花分化和籽粒生长过程的伤害,最终可显著减少臭氧胁迫下经济产量的损失。展开更多
Analysis of tropospheric ozone residual (TOR) data from satellite measurements indicates an increasing trend of tropospheric ozone over the Yangtze Delta region of China. The increasing trend can be derived both from ...Analysis of tropospheric ozone residual (TOR) data from satellite measurements indicates an increasing trend of tropospheric ozone over the Yangtze Delta region of China. The increasing trend can be derived both from the annual mean TOR and from the monthly mean TOR except for January and March. The increase rate of the decadal mean TOR was 0.82 DU during 1978-2000. The impact of this long-term trend on the climate and atmospheric oxidizing capacity over the region should be further studied. Data comparison shows a significant correlation between the TOR and surface ozone data collected at Lin'an background station in the Yangtze Delta region, suggesting an internal connection between both quantities.展开更多
For physical ozone absorption without reaction,two parametric estimation methods,i.e.the common linear least square fitting and non-linear Simplex search methods,were applied,respectively,to determine the ozone mass t...For physical ozone absorption without reaction,two parametric estimation methods,i.e.the common linear least square fitting and non-linear Simplex search methods,were applied,respectively,to determine the ozone mass transfer coefficient during absorption and both methods give almost the same mass transfer coefficient.While for chemical absorption with ozone decomposition reaction,the common linear least square fitting method is not applicable for the evaluation of ozone mass transfer coefficient due to the difficulty of model linearization for describing ozone concentration dissolved in water.The nonlinear Simplex method obtains the mass transfer coefficient by minimizing the sum of the differences between the simulated and experimental ozone concentration during the whole absorption process,without the limitation of linear relationship between the dissolved ozone concentration and absorption time during the initial stage of absorption.Comparison of the ozone concentration profiles between the simulation and experimental data demonstrates that Simplex method may determine ozone mass transfer coefficient during absorption in an accurate and high efficiency way with wide applicability.展开更多
Surface ozone is among the greenhouse gases which form a blanket that causes the heat trapping effect and warms the atmosphere with related consequences such as atmospheric temperature rise. The aim of this study is t...Surface ozone is among the greenhouse gases which form a blanket that causes the heat trapping effect and warms the atmosphere with related consequences such as atmospheric temperature rise. The aim of this study is to investigate the temporal relationship between the meteorological conditions and the surface ozone concentrations.In this study surface ozone and meteorological measurements展开更多
Climate change is temperature inversion as a result of the stratospheric ozone depletion.This depletion is caused by Ozone Depleting Substances(ODS)having high Ozone Depleting Potentials(ODP)such as chloric fluorocarb...Climate change is temperature inversion as a result of the stratospheric ozone depletion.This depletion is caused by Ozone Depleting Substances(ODS)having high Ozone Depleting Potentials(ODP)such as chloric fluorocarbons and hydrochloric fluorocarbons(used as refrigerant coolant in refrigerators,air conditioners etc.), nitrogen tetrafluoride(in plasma screen),and green house effect,all these caused by the accumulation of green house gases(GHG)in the atmosphere such as展开更多
Desulfurization and denitrification by using ozone has been widely used in recent years,but the technology for generating ozone at this stage has some shortcomings,which needs to be improved urgently.This paper advoca...Desulfurization and denitrification by using ozone has been widely used in recent years,but the technology for generating ozone at this stage has some shortcomings,which needs to be improved urgently.This paper advocates using mud-phosphorous slurry to produce ozone,which is environmentally friendly and economical.At the same time,SO_(2) and NO_(x) can be removed from mud-phosphorous slurry simultaneously.The amount of ozone generated during desulfurization and denitrification is particularly important,thus,this paper studies the effects of the temperature of reaction,oxygen content and solid-liquid ratio of mud-phosphorus slurry on the amount of ozone generated.The results showed that under the optimum conditions(the reaction temperature was 60℃,the solid-liquid ratio of mud-phosphorus slurry was 5.0 g/40 mL,the oxygen content was 30%),the amount of ozone was the largest,and the maximum generation amount was 573.8 mg/m^(3).Under these conditions,the removal rates of SO_(2) and NO_(x) can reach 99.5%and 99%respectively.This paper also analyzes the products of desulfurization and denitrification,and proposes the corresponding reaction mechanism.展开更多
OZOHE PROTECTION FOR THE 90’S INTERNATIONAL WORKSHOP AFCAM and AIRAH,assistance from DASETT,have been holding a South East Asian and South Pacific Workshop on Ozoen Protection for the’90s at the National Convention,...OZOHE PROTECTION FOR THE 90’S INTERNATIONAL WORKSHOP AFCAM and AIRAH,assistance from DASETT,have been holding a South East Asian and South Pacific Workshop on Ozoen Protection for the’90s at the National Convention,Centre,Canberra from 23 to 26 March 1992. The workshop focus technology transfer,under UNEP,to countries in south East Asia and the South Pacific.This should significantly assist ozone protection in the region and provide commercial opportunities for Australian firms and organlsations. The Ozone Protection for the’90s workshop provide a forum for papers and lssues fordiscussion include:展开更多
基金Project(2022M710619)supported by the Postdoctoral Science Foundation of ChinaProjects(2020YFH0213,2020YFG0039)supported by the Sichuan Science and Technology Program,China+1 种基金Projects(XJ2024001501,KCXTD2023-4)supported by the Basic Scientific Foundation and Innovation Team Funds of China West Normal UniversityProject(CSPC202403)supported by the Open Project Program of Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province,China。
文摘In response to the fact that the presence of manganese dithionate(MnS_(2)O_(6))leads to a series of adverse impacts,especially lower purity of manganese sulfate(MnSO_(4))and disruption of its recovery,advanced oxidation methods such as ozonation system are used to manage MnS_(2)O_(6)in the leaching solution,replacing conventional methods.To ascertain the conversion rate and kinetics of MnS_(2)O_(6)during the ozonation process,we explored the factors influencing its removal rate,including ozone dosage,manganese dithionate concentration,sulfuric acid concentration,and reaction temperature.Batch experiments were conducted to determine the reaction rate constant of ozone(k)and activation energy(Ea)obtained from intermittent experimental data fitting,revealing a least-squares exponential conversion relationship between k and the MnS_(2)O_(6)removal amount,wherein an increase in the aforementioned factors led to an enhanced MnS_(2)O_(6)conversion rate,exceeding 99.3%.The formation mechanism of the ozone products proposed during the experiment was summarized and proposed as follows:1)Mn^(2+)was directly oxidized to MnO_(2),and 2)SO_(4)2−was obtained by the catalytic oxidation of S_(2)O_(6)^(2−)with HO•from O3 decomposition.According to the kinetics analysis,the pre-exponential factor and total activation energy of the ozonation kinetics equation were 1.0×10^(23) s^(−1) and 177.28 kJ/mol,respectively.Overall,the present study demonstrates that O_(3) as an oxidizing agent can effectively facilitate MnS_(2)O_(6)disproportionation while preventing the release of the secondary pollutant,SO_(2)gas.
基金Project(40973074) supported by the National Natural Science Foundation of China
文摘A novel heterogeneous catalytic ozonation process in water treatment was studied, with a copper-loaded activated carbon （Cu/AC） that was prepared by an incipient wetness impregnation method at low temperature and tested as a catalyst in the ozonation of phenol and oxalic acid. Cu/AC was characterized using XRD, BET and SEM techniques. Compared with ozonation alone, the presence of Cu/AC in the ozonation processes significantly improves the degradation of phenol or oxalic acid. With the introduction of the hydroxyl radical scavenger, i.e., turt-butanol alcohol （t-BuOH）, the degradation efficiency of both phenol and oxalic acid in the Cu/AC catalyzed ozonation process decreases by 22% at 30 min. This indicates that Cu/AC accelerates ozone decomposition into certain concentration of hydroxyl radicals. The amount of Cu（II ） produced during the reaction of Cu/AC-catalyzed ozonation of phenol or oxalic acid is very small, which shows that the two processes are both heterogeneous catalytic ozonation reactions.
文摘依托中国稻田臭氧FACE(Free Air ozone Concentration Enrichment)技术平台,以常规籼稻扬稻6号为供试材料,设置大气臭氧浓度(Ambient)和高臭氧浓度(比Ambient高50%),移栽密度设置低密度(16穴/m2)、中密度(24穴/m2)和高密度(32穴/m2),研究不同移栽密度下近地层臭氧浓度升高对水稻生长发育和产量的影响。结果表明,高浓度臭氧对水稻抽穗期、成熟期和最终株高均无显著影响,但使收获期生物产量显著下降,其中低、中和高密度条件下分别下降23%、20%和9%。臭氧胁迫导致的生物产量下降主要与拔节至抽穗期物质生产量明显下降有关(-23%),而营养生长期物质生产量差异不显著。前者主要与高浓度臭氧下水稻生长后期的净同化率(NAR)显著下降有关,也与该期叶面积指数(LAI)下降部分相关。高浓度臭氧对营养生长期不同器官生物量影响较小,但可使生殖生长期各器官生物量显著下降,其中茎鞘生物量降幅大于叶片,因此,臭氧胁迫下生物量在叶片中的分配比例呈增加趋势,而在茎鞘中的分配比例则相反。臭氧胁迫对单位面积穗数和每穗颖花数均无显著影响,但使饱粒率和饱粒重显著下降,空粒率和秕粒率明显增加。臭氧胁迫使水稻籽粒产量平均下降16%,其中,低、中、高密度下分别下降24%、14%和10%。臭氧胁迫对水稻生长后期的LAI、NAR、物质生产量以及每穗颖花数、饱粒重和籽粒产量的负面影响均随密度的增加而呈减小的趋势。以上结果表明,适当增加移栽密度可以减小臭氧胁迫对水稻生长后期的光合面积特别是净同化率的影响,进而减轻对颖花分化和籽粒生长过程的伤害,最终可显著减少臭氧胁迫下经济产量的损失。
文摘Analysis of tropospheric ozone residual (TOR) data from satellite measurements indicates an increasing trend of tropospheric ozone over the Yangtze Delta region of China. The increasing trend can be derived both from the annual mean TOR and from the monthly mean TOR except for January and March. The increase rate of the decadal mean TOR was 0.82 DU during 1978-2000. The impact of this long-term trend on the climate and atmospheric oxidizing capacity over the region should be further studied. Data comparison shows a significant correlation between the TOR and surface ozone data collected at Lin'an background station in the Yangtze Delta region, suggesting an internal connection between both quantities.
基金Project(2011467001)supported by the Ministry of Environment Protection of ChinaProject(2010DFB94130)supported by the Ministry of Science and Technology of China
文摘For physical ozone absorption without reaction,two parametric estimation methods,i.e.the common linear least square fitting and non-linear Simplex search methods,were applied,respectively,to determine the ozone mass transfer coefficient during absorption and both methods give almost the same mass transfer coefficient.While for chemical absorption with ozone decomposition reaction,the common linear least square fitting method is not applicable for the evaluation of ozone mass transfer coefficient due to the difficulty of model linearization for describing ozone concentration dissolved in water.The nonlinear Simplex method obtains the mass transfer coefficient by minimizing the sum of the differences between the simulated and experimental ozone concentration during the whole absorption process,without the limitation of linear relationship between the dissolved ozone concentration and absorption time during the initial stage of absorption.Comparison of the ozone concentration profiles between the simulation and experimental data demonstrates that Simplex method may determine ozone mass transfer coefficient during absorption in an accurate and high efficiency way with wide applicability.
文摘Surface ozone is among the greenhouse gases which form a blanket that causes the heat trapping effect and warms the atmosphere with related consequences such as atmospheric temperature rise. The aim of this study is to investigate the temporal relationship between the meteorological conditions and the surface ozone concentrations.In this study surface ozone and meteorological measurements
文摘Climate change is temperature inversion as a result of the stratospheric ozone depletion.This depletion is caused by Ozone Depleting Substances(ODS)having high Ozone Depleting Potentials(ODP)such as chloric fluorocarbons and hydrochloric fluorocarbons(used as refrigerant coolant in refrigerators,air conditioners etc.), nitrogen tetrafluoride(in plasma screen),and green house effect,all these caused by the accumulation of green house gases(GHG)in the atmosphere such as
基金Projects(51968075,51568067)supported by the National Natural Science Foundation of ChinaProject(2018FD054)supported by the Applied Basic Research Surface Project of Yunnan Province,ChinaProject(2020Y0259)supported by the Scientific Research Fund Project of Yunnan Provincial Department of Education,China。
文摘Desulfurization and denitrification by using ozone has been widely used in recent years,but the technology for generating ozone at this stage has some shortcomings,which needs to be improved urgently.This paper advocates using mud-phosphorous slurry to produce ozone,which is environmentally friendly and economical.At the same time,SO_(2) and NO_(x) can be removed from mud-phosphorous slurry simultaneously.The amount of ozone generated during desulfurization and denitrification is particularly important,thus,this paper studies the effects of the temperature of reaction,oxygen content and solid-liquid ratio of mud-phosphorus slurry on the amount of ozone generated.The results showed that under the optimum conditions(the reaction temperature was 60℃,the solid-liquid ratio of mud-phosphorus slurry was 5.0 g/40 mL,the oxygen content was 30%),the amount of ozone was the largest,and the maximum generation amount was 573.8 mg/m^(3).Under these conditions,the removal rates of SO_(2) and NO_(x) can reach 99.5%and 99%respectively.This paper also analyzes the products of desulfurization and denitrification,and proposes the corresponding reaction mechanism.
文摘OZOHE PROTECTION FOR THE 90’S INTERNATIONAL WORKSHOP AFCAM and AIRAH,assistance from DASETT,have been holding a South East Asian and South Pacific Workshop on Ozoen Protection for the’90s at the National Convention,Centre,Canberra from 23 to 26 March 1992. The workshop focus technology transfer,under UNEP,to countries in south East Asia and the South Pacific.This should significantly assist ozone protection in the region and provide commercial opportunities for Australian firms and organlsations. The Ozone Protection for the’90s workshop provide a forum for papers and lssues fordiscussion include:
