In this paper, we present the results of the evaluation of three low-cost laser sensor</span><span style="font-family:Verdana;">s</span><span style="font-family:""><...In this paper, we present the results of the evaluation of three low-cost laser sensor</span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> and comparison with the standard device Metone Aerocet 531s which is capable of counting dust particles as small as 0.3 μm. The sensors used in this study are PMS5003 (Plantower), SPS30 (Sesirion), SM-UART-04L (Amphenol). During the measurement, the overall trend of the outputs from the sensors was similar to that of the Aerocet 531s. The PMS5003 sensor has a relatively small standard error in the all particle measurement ranges (<15 μg/m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> in the low particle concentration range). All sensors have a high linearity compared to data from standard equipment, PMS5003: PM1.0 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.89;PM2.5 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.95;PM10 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.87;SPS30 PM2.5 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.95 and PM10 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.99;SM-UART-04L PM1.0 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.98. Three main sensor calibration methods (single-point calibration, two-point calibration and multi-point curve correction) with implementation steps for each method as well as their practical applications in calibrating low-cost air quality sensors according to standard measuring equipment are also detailed illustrated.展开更多
The increased occurrence of smoggy days in major Chinese cities is of major concern to the general public. This paper explores the major sources of PM2.5 pollutants, a key contributor to the smog in Beijing, one of Ch...The increased occurrence of smoggy days in major Chinese cities is of major concern to the general public. This paper explores the major sources of PM2.5 pollutants, a key contributor to the smog in Beijing, one of China’s largest cities. Evidence indicates that the secondary PM2.5 particles formed through NOx, SOx, NH3, VOCs, etc. have a strong impact on human health. As a result, PM2.5 pollution control should not simply focus on controlling particulate emission, but should involve adopting an integrated multi-pollutant control strategy. In addition to identifying the major sources of PM2.5, this paper explores its impact on environmental and human health. Although the intention of this research is not to provide solutions for reducing PM2.5 pollution, the paper analyzes the United States’ experience with establishing PM2.5 standards and mandates. Specifically, this paper focuses on the air quality control strategies adopted in California since the 1940s and draws parallels with present-day China. The research suggests that adequate government regulation, public awareness, regional collaboration and industrial compliance are keys to successfully controlling PM2.5 pollution.展开更多
Vehicle exhaust and transported biomass burning emissions are important air pollution sources in many urban areas,and domestic cooking with biomass fuels causes indoor air pollution in many rural areas.Using agricultu...Vehicle exhaust and transported biomass burning emissions are important air pollution sources in many urban areas,and domestic cooking with biomass fuels causes indoor air pollution in many rural areas.Using agricultural waste-generated synthetic fuels can reduce emissions both from vehicles and biomass burning.To estimate the potential benefits of synthetic diesel in Beijing,the emission factor model for the Beijing vehicle fleet was applied to estimate exhaust emissions for the 2015-2030 period.Compared with 100%petroleum diesel,a 20%synthetic diesel blend reduced diesel fleet emissions by 24%for carbon monoxide,30%for total hydrocarbons,5.5%for nitrogen oxides,and 19%for fine particulate matter with an aerodynamic diameter of≤2.5μm(PM2.5)while using 100%synthetic diesel decreased emissions by 36%for carbon monoxide,48%for total hydrocarbons,10%for nitrogen oxides,and 34%for PM2.5.The use of biomass for producing synthetic fuels rather than burning in the field also reduces air pollution.Over 60g of PM2.5 agricultural open-field burning emissions are avoided per liter of synthetic fuel produced.Replacing solid crop residues with synthetic liquid fuels in household cooking would reduce PM2.5 emissions by more than 90%.展开更多
A rapid reaction occurs near the exhaust nozzle when vehicle emissions contact the air.Twenty diesel vehicles were studied using a new multipoint sampling system that is suitable for studying the exhaust plume near th...A rapid reaction occurs near the exhaust nozzle when vehicle emissions contact the air.Twenty diesel vehicles were studied using a new multipoint sampling system that is suitable for studying the exhaust plume near the exhaust nozzle.The variation characteristics of fine particle matter(PM_(2.5)) and its components in diesel vehicle exhaust plumes were analyzed.The PM_(2.5) emissions gradually increased with increasing distance from the nozzle in the plume.Elemental carbon emissions remained basically unchanged, organic carbon and total carbon(TC) increased with increasing distance.The concentrations of SO_(4)^(2-),NO_(3)^(-) and NH_(4)^(+) (SNA) directly emitted by the vehicles were very low but increased rapidly in the exhaust plume.The selective catalytic reduction(SCR) reduced 42.7% TC, 40% NO_(3)^(-) emissions, but increased 104% SO_(4)^(2-) and 36% NH_(4)^(+) emissions, respectively.In summary,the SCR reduced 29% primary PM_(2.5) emissions for the tested diesel vehicles.The NH_(4)NO_(3) particle formation maybe more important in the plume, and there maybe other forms of formation of NH_(4)^(+) (eg.NH4Cl).The generation of secondary organic carbon(SOC) plays a leading role in the generation of secondary PM_(2.5).The SCR enhanced the formation of SOC and SNA in the plume, but comprehensive analysis shows that the SCR more enhanced the SNA formation in the plume, which is mainly new particles formation process.The inconsistency between secondary organic aerosol(SOA) and primary organic aerosol definitions is one of the important reasons for the difference between SOA simulation and observation.展开更多
Recently,Chinese megacities have suffered serious air pollution.Previous studies have pointed out that transportation systems have become one of the major sources of air pollution and on-road pollutant concentrations ...Recently,Chinese megacities have suffered serious air pollution.Previous studies have pointed out that transportation systems have become one of the major sources of air pollution and on-road pollutant concentrations are significantly higher than off-road.Electric vehicle(EV)introduction is proposed as a method to alleviate the current situation.In order to better understand the benefit of the use of EVs in Beijing,a simulation platform has been developed to evaluate the improvement of air quality with the use of EVs quantitatively within the selected area.Four scenarios with different EV penetration rates are proposed and the results revealed 5%,10%,15%EV penetration rates which will bring about improvement of 0.86%,9.01%and 12.23%for PM2.5,0.92%,9.01%and 13.32%for nitrogen oxides(NO_(x)),0.95%,8.86%and 13.73%for CO,respectively.The results revealed a promising improvement of air quality with the introduction of EVs.展开更多
This paper examines the energy and environmental benefits within the whole life cycle shifting from traditional gasoline vehicles to electrified advanced vehicles under regional real-world driving behaviors. The advan...This paper examines the energy and environmental benefits within the whole life cycle shifting from traditional gasoline vehicles to electrified advanced vehicles under regional real-world driving behaviors. The advance vehicles focus on family passenger cars and include battery electric vehicles （BEVs）, plug-in hybrid electric vehicles （PHEVs）, and hybrid electric vehicles （HEVs）. The GREET （greenhouse gases, regulated emissions, and energy use in transportation） model is adopted with regional circumstances modifications, especially the UF （utility factors） of PHEVs. The results show that the electrified vehicles offer great benefits concerning energy consumption, greenhouse gas （GHG） emissions as well as urban Particulate Matter 2,5 （PMz.s） emissions. Compared to conventional gasoline vehicles, the life-cycle total energy reduction for advance vehicles is 51% to 57%. There is little difference on energy reduction among the HEVs, PHEVs and BEVs, with the energy mix shifting from petroleum to coal for the stronger electrification. The reductions of GHG emissions are 57% for HEV, 54% to 48% for PHEVs with 10 miles to 40 miles CD range, and 40% for BEV. The life-cycle and local PM2.5 emissions are discussed separately. The life-cycle PM2.5 emissions increase with vehicle electrification and reach a maximum for the BEV which are 5% higher than the conventional vehicle （CV）. However, electric vehicles can shift PM2.5 emissions from vehicle operation to upstream operations and help mitigate PM2.5 emissions in urban areas. The local emissions of PHEVs and BEVs can be reduced by 37% to 81% and 100% compared with CVs.展开更多
文摘In this paper, we present the results of the evaluation of three low-cost laser sensor</span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> and comparison with the standard device Metone Aerocet 531s which is capable of counting dust particles as small as 0.3 μm. The sensors used in this study are PMS5003 (Plantower), SPS30 (Sesirion), SM-UART-04L (Amphenol). During the measurement, the overall trend of the outputs from the sensors was similar to that of the Aerocet 531s. The PMS5003 sensor has a relatively small standard error in the all particle measurement ranges (<15 μg/m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> in the low particle concentration range). All sensors have a high linearity compared to data from standard equipment, PMS5003: PM1.0 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.89;PM2.5 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.95;PM10 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.87;SPS30 PM2.5 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.95 and PM10 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.99;SM-UART-04L PM1.0 R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> = 0.98. Three main sensor calibration methods (single-point calibration, two-point calibration and multi-point curve correction) with implementation steps for each method as well as their practical applications in calibrating low-cost air quality sensors according to standard measuring equipment are also detailed illustrated.
文摘The increased occurrence of smoggy days in major Chinese cities is of major concern to the general public. This paper explores the major sources of PM2.5 pollutants, a key contributor to the smog in Beijing, one of China’s largest cities. Evidence indicates that the secondary PM2.5 particles formed through NOx, SOx, NH3, VOCs, etc. have a strong impact on human health. As a result, PM2.5 pollution control should not simply focus on controlling particulate emission, but should involve adopting an integrated multi-pollutant control strategy. In addition to identifying the major sources of PM2.5, this paper explores its impact on environmental and human health. Although the intention of this research is not to provide solutions for reducing PM2.5 pollution, the paper analyzes the United States’ experience with establishing PM2.5 standards and mandates. Specifically, this paper focuses on the air quality control strategies adopted in California since the 1940s and draws parallels with present-day China. The research suggests that adequate government regulation, public awareness, regional collaboration and industrial compliance are keys to successfully controlling PM2.5 pollution.
文摘Vehicle exhaust and transported biomass burning emissions are important air pollution sources in many urban areas,and domestic cooking with biomass fuels causes indoor air pollution in many rural areas.Using agricultural waste-generated synthetic fuels can reduce emissions both from vehicles and biomass burning.To estimate the potential benefits of synthetic diesel in Beijing,the emission factor model for the Beijing vehicle fleet was applied to estimate exhaust emissions for the 2015-2030 period.Compared with 100%petroleum diesel,a 20%synthetic diesel blend reduced diesel fleet emissions by 24%for carbon monoxide,30%for total hydrocarbons,5.5%for nitrogen oxides,and 19%for fine particulate matter with an aerodynamic diameter of≤2.5μm(PM2.5)while using 100%synthetic diesel decreased emissions by 36%for carbon monoxide,48%for total hydrocarbons,10%for nitrogen oxides,and 34%for PM2.5.The use of biomass for producing synthetic fuels rather than burning in the field also reduces air pollution.Over 60g of PM2.5 agricultural open-field burning emissions are avoided per liter of synthetic fuel produced.Replacing solid crop residues with synthetic liquid fuels in household cooking would reduce PM2.5 emissions by more than 90%.
基金supported by the National Natural Science Foundation of China (No.41605095)the Beijing Natural Science Foundation (No.JQ19030)+1 种基金the Beijing Municipal Commission of Education (No.PXM2019014213000007)the School Level Cultivation Fund of Beijing Technology and Business University for Distinguished and Excellent Young Scholars (No.BTBUYP2020)。
文摘A rapid reaction occurs near the exhaust nozzle when vehicle emissions contact the air.Twenty diesel vehicles were studied using a new multipoint sampling system that is suitable for studying the exhaust plume near the exhaust nozzle.The variation characteristics of fine particle matter(PM_(2.5)) and its components in diesel vehicle exhaust plumes were analyzed.The PM_(2.5) emissions gradually increased with increasing distance from the nozzle in the plume.Elemental carbon emissions remained basically unchanged, organic carbon and total carbon(TC) increased with increasing distance.The concentrations of SO_(4)^(2-),NO_(3)^(-) and NH_(4)^(+) (SNA) directly emitted by the vehicles were very low but increased rapidly in the exhaust plume.The selective catalytic reduction(SCR) reduced 42.7% TC, 40% NO_(3)^(-) emissions, but increased 104% SO_(4)^(2-) and 36% NH_(4)^(+) emissions, respectively.In summary,the SCR reduced 29% primary PM_(2.5) emissions for the tested diesel vehicles.The NH_(4)NO_(3) particle formation maybe more important in the plume, and there maybe other forms of formation of NH_(4)^(+) (eg.NH4Cl).The generation of secondary organic carbon(SOC) plays a leading role in the generation of secondary PM_(2.5).The SCR enhanced the formation of SOC and SNA in the plume, but comprehensive analysis shows that the SCR more enhanced the SNA formation in the plume, which is mainly new particles formation process.The inconsistency between secondary organic aerosol(SOA) and primary organic aerosol definitions is one of the important reasons for the difference between SOA simulation and observation.
基金supported by the project“Research on the Traffic Environment Carrying Capacity and Feedback Gating Based Dynamic Traffic Control in Urban Network”which is funded by the China Postdoctoral Science Foundation with Grant no.2013M540102supported by the project“The research and application of the urban air environment regulation and control technology based on the Internet of Things”,which is under the State High-Tech Development Plan(The 863 program)+1 种基金funded by The Ministry of Science and Technology of the People’s Republic of China(Project No.2012AA063303)support for providing data and technology support.
文摘Recently,Chinese megacities have suffered serious air pollution.Previous studies have pointed out that transportation systems have become one of the major sources of air pollution and on-road pollutant concentrations are significantly higher than off-road.Electric vehicle(EV)introduction is proposed as a method to alleviate the current situation.In order to better understand the benefit of the use of EVs in Beijing,a simulation platform has been developed to evaluate the improvement of air quality with the use of EVs quantitatively within the selected area.Four scenarios with different EV penetration rates are proposed and the results revealed 5%,10%,15%EV penetration rates which will bring about improvement of 0.86%,9.01%and 12.23%for PM2.5,0.92%,9.01%and 13.32%for nitrogen oxides(NO_(x)),0.95%,8.86%and 13.73%for CO,respectively.The results revealed a promising improvement of air quality with the introduction of EVs.
基金The Ministry of Science and Technology of China(Grant Nos.2011DFA60650,2012DFA81190,2014DFG71590,2013BAG06B02 and 2013BAG06B04)
文摘This paper examines the energy and environmental benefits within the whole life cycle shifting from traditional gasoline vehicles to electrified advanced vehicles under regional real-world driving behaviors. The advance vehicles focus on family passenger cars and include battery electric vehicles （BEVs）, plug-in hybrid electric vehicles （PHEVs）, and hybrid electric vehicles （HEVs）. The GREET （greenhouse gases, regulated emissions, and energy use in transportation） model is adopted with regional circumstances modifications, especially the UF （utility factors） of PHEVs. The results show that the electrified vehicles offer great benefits concerning energy consumption, greenhouse gas （GHG） emissions as well as urban Particulate Matter 2,5 （PMz.s） emissions. Compared to conventional gasoline vehicles, the life-cycle total energy reduction for advance vehicles is 51% to 57%. There is little difference on energy reduction among the HEVs, PHEVs and BEVs, with the energy mix shifting from petroleum to coal for the stronger electrification. The reductions of GHG emissions are 57% for HEV, 54% to 48% for PHEVs with 10 miles to 40 miles CD range, and 40% for BEV. The life-cycle and local PM2.5 emissions are discussed separately. The life-cycle PM2.5 emissions increase with vehicle electrification and reach a maximum for the BEV which are 5% higher than the conventional vehicle （CV）. However, electric vehicles can shift PM2.5 emissions from vehicle operation to upstream operations and help mitigate PM2.5 emissions in urban areas. The local emissions of PHEVs and BEVs can be reduced by 37% to 81% and 100% compared with CVs.
