The Beijing“Coal to Electricity”program provides a unique opportunity to explore air quality impacts by replacing residential coal burning with electrical appliances.In this study,the atmospheric ROS(Gas-phase ROS a...The Beijing“Coal to Electricity”program provides a unique opportunity to explore air quality impacts by replacing residential coal burning with electrical appliances.In this study,the atmospheric ROS(Gas-phase ROS and Particle-phase ROS,abbreviated to G-ROS and P-ROS)were measured by an online instrument in parallel with concurrent PM_(2.5) sample collections analyzed for chemical composition and cellular ROS in a baseline year(Coal Use Year-CUY)and the first year following implementation of the“Coal to Electricity”program(Coal Ban Year-CBY).The results showed PM_(2.5) concentrations had no significant difference between the two sampling periods,but the activities of G-ROS,P-ROS,and cellular ROS in CBY were 8.72 nmol H_(2)O_(2)/m^(3),9.82 nmol H 2 O 2/m 3,and 2045.75μg UD/mg PM higher than in CUY.Six sources were identified by factor-analysis from the chemical components of PM_(2.5).Secondary sources(SECs)were the dominant source of PM_(2.5) in the two periods,with 15.90%higher contribution in CBY than in CUY.Industrial Emission&Coal Combustion sources(Ind.&CCs),mainly from regional transport,also increased significantly in CBY.The contributions of Aged Sea Salt&Residential Burning sources to PM_(2.5) decreased 5.31% from CUY to CBY.The correlation results illustrated that Ind.&CCs had significant positive correlations with atmospheric ROS,and SECs significantly associated with cellular ROS,especially nitrates(r=0.626,p=0.000).Therefore,the implementation of the“Coal to Electricity”program reduced PM_(2.5) contributions from coal and biomass combustion,but had little effect on the improvement of atmospheric and cellular ROS.展开更多
In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples...In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples and various pollution sources which were collected in January 2010 in Longyan with inductivity coupled plasma-mass spectrometry(ICP-MS).Then chemical mass balance(CMB) model and factor analysis(FA) method were applied to comparatively study the inorganic components in the sources and receptor samples.The results of factor analysis show that the major sources were road dust,waste incineration and mixed sources which contained automobile exhaust,soil dust/secondary dust and coal dust during the daytime in Longyan City,China.There are two major sources of pollution which are soil dust and mixture sources of automobile exhaust and secondary dust during the night in Longyan.The results of CMB show that the major sources are secondary dust,automobile exhaust and road dust during the daytime in Longyan.The major sources are secondary dust,soil dust and automobile exhaust during the night in Longyan.The results of the two methods are similar to each other and the results will guide us to plan to control the PM10 pollution sources in Longyan.展开更多
为预防和控制引水隧洞中围岩失稳事故的发生,将物元可拓法应用于围岩稳定性评价中。以滇中引水工程为背景,选取滇中引水工程某隧洞段,构建引水隧洞围岩稳定性评价指标体系,划分围岩等级,选用灰色关联分析法(Grey Relational Analysis, G...为预防和控制引水隧洞中围岩失稳事故的发生,将物元可拓法应用于围岩稳定性评价中。以滇中引水工程为背景,选取滇中引水工程某隧洞段,构建引水隧洞围岩稳定性评价指标体系,划分围岩等级,选用灰色关联分析法(Grey Relational Analysis, GRA)和因子分析法(Factor Analysis, FA)组合确定权重,基于物元可拓模型进行引水隧洞围岩稳定性评价,以期减少目前评价方法中一些不相容现象及其他问题所带来的影响,从而提升长距离特大输水工程围岩稳定性等级评价的精度。结果表明,GRA-FA-物元可拓模型围岩稳定性评价结果与实际等级基本相符,与逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution, TOPSIS)相比,预测评价精度从62.5%提升到87.5%,准确性提升了约25百分点。因此,GRA-FA-物元可拓模型相较以往的评价模型可以更全面和客观地进行引水隧洞围岩稳定性评价,可为其他长距离特大引水工程施工风险评价提供理论支撑。展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(No.41877310)partly by the National Key Research and Development Program of China(No.2016YFC0503600).
文摘The Beijing“Coal to Electricity”program provides a unique opportunity to explore air quality impacts by replacing residential coal burning with electrical appliances.In this study,the atmospheric ROS(Gas-phase ROS and Particle-phase ROS,abbreviated to G-ROS and P-ROS)were measured by an online instrument in parallel with concurrent PM_(2.5) sample collections analyzed for chemical composition and cellular ROS in a baseline year(Coal Use Year-CUY)and the first year following implementation of the“Coal to Electricity”program(Coal Ban Year-CBY).The results showed PM_(2.5) concentrations had no significant difference between the two sampling periods,but the activities of G-ROS,P-ROS,and cellular ROS in CBY were 8.72 nmol H_(2)O_(2)/m^(3),9.82 nmol H 2 O 2/m 3,and 2045.75μg UD/mg PM higher than in CUY.Six sources were identified by factor-analysis from the chemical components of PM_(2.5).Secondary sources(SECs)were the dominant source of PM_(2.5) in the two periods,with 15.90%higher contribution in CBY than in CUY.Industrial Emission&Coal Combustion sources(Ind.&CCs),mainly from regional transport,also increased significantly in CBY.The contributions of Aged Sea Salt&Residential Burning sources to PM_(2.5) decreased 5.31% from CUY to CBY.The correlation results illustrated that Ind.&CCs had significant positive correlations with atmospheric ROS,and SECs significantly associated with cellular ROS,especially nitrates(r=0.626,p=0.000).Therefore,the implementation of the“Coal to Electricity”program reduced PM_(2.5) contributions from coal and biomass combustion,but had little effect on the improvement of atmospheric and cellular ROS.
基金Supported by the Natural Basic Research Program of China(No.2005CB422207)the Fund of Eco-enviromental Impacts and Protection in Devoloping and Utilizing of Oil-shale Resources(No.OSR-01-06)
文摘In order to identify the day and night pollution sources of PM10 in ambient air in Longyan City,the authors analyzed the elemental composition of respirable particulate matters in the day and night ambient air samples and various pollution sources which were collected in January 2010 in Longyan with inductivity coupled plasma-mass spectrometry(ICP-MS).Then chemical mass balance(CMB) model and factor analysis(FA) method were applied to comparatively study the inorganic components in the sources and receptor samples.The results of factor analysis show that the major sources were road dust,waste incineration and mixed sources which contained automobile exhaust,soil dust/secondary dust and coal dust during the daytime in Longyan City,China.There are two major sources of pollution which are soil dust and mixture sources of automobile exhaust and secondary dust during the night in Longyan.The results of CMB show that the major sources are secondary dust,automobile exhaust and road dust during the daytime in Longyan.The major sources are secondary dust,soil dust and automobile exhaust during the night in Longyan.The results of the two methods are similar to each other and the results will guide us to plan to control the PM10 pollution sources in Longyan.
文摘为预防和控制引水隧洞中围岩失稳事故的发生,将物元可拓法应用于围岩稳定性评价中。以滇中引水工程为背景,选取滇中引水工程某隧洞段,构建引水隧洞围岩稳定性评价指标体系,划分围岩等级,选用灰色关联分析法(Grey Relational Analysis, GRA)和因子分析法(Factor Analysis, FA)组合确定权重,基于物元可拓模型进行引水隧洞围岩稳定性评价,以期减少目前评价方法中一些不相容现象及其他问题所带来的影响,从而提升长距离特大输水工程围岩稳定性等级评价的精度。结果表明,GRA-FA-物元可拓模型围岩稳定性评价结果与实际等级基本相符,与逼近理想解排序法(Technique for Order Preference by Similarity to Ideal Solution, TOPSIS)相比,预测评价精度从62.5%提升到87.5%,准确性提升了约25百分点。因此,GRA-FA-物元可拓模型相较以往的评价模型可以更全面和客观地进行引水隧洞围岩稳定性评价,可为其他长距离特大引水工程施工风险评价提供理论支撑。