PM2.5 filter sampling and components measurement were conducted in autumn and winter from 2014 to 2015 at a suburban site(referred herein as "LLH site") located in the southwest of *** offline aerosol mass s...
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PM2.5 filter sampling and components measurement were conducted in autumn and winter from 2014 to 2015 at a suburban site(referred herein as "LLH site") located in the southwest of *** offline aerosol mass spectrometry(offline-AMS) analysis and positive matrix factorization(PMF) were applied for measurement and source apportionment of watersoluble organic aerosol(WSOA).Organic aerosol(OA) always dominated PM2.5 during the sampling period,especially in *** pollution was serious during the polluted period both in autumn(31.1 μg/m3) and winter(31.9 μg/m3),while WSOA accounted for 54.4%of OA during the polluted period in autumn,much more than that(21.3%) in *** oxidation degree of WSOA at LLH site was at a high level(oxygen-to-carbon ratio,O/C=0.91)and secondary organic aerosol(SOA) contributed more mass ratio of WSOA than primary organic aerosol(POA) during the whole observation *** winter,coal combustion OA(CCOA) was a stable source of OA and on average accounted for 25.1% of *** autumn,biomass burning OA(BBOA) from household combustion contributed 38.3% of WSOA during polluted *** addition to oxygenated OA(OOA),aqueous-oxygenated OA(aq-OOA) was identified as an important factor of *** heavy pollution period,the mass proportion of aq-OOA to WSOA increased significantly,implying the significant SOA formation through aqueous-phase *** result of this study highlights the concentration on controlling the residential coal and biomass burning,as well as the research needs on aqueous chemistry in OA formation.
With the increasing role of distributed message systems (DMS) represented by Kafka in handling large-scale data streams, it is critical to improve system performance by optimizing configuration parameters in different...
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China promulgated the Air Pollution Prevention and Control Action Plan(the Action Plan)in 2013 and developed stringent control measures to mitigate fine particulate matter(PM2.5) ***,we investigated the PM2.5 chemical...
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China promulgated the Air Pollution Prevention and Control Action Plan(the Action Plan)in 2013 and developed stringent control measures to mitigate fine particulate matter(PM2.5) ***,we investigated the PM2.5 chemical composition changes over eastern China associated with the Action Plan during 2013-2017 using satellite-based PM2.5 chemical composition data derived using CMAQ simulations and satellite *** PM2.5 concentrations decreased considerably during this time as a result of the reductions in all chemical species in *** population-weighted mean concentrations over eastern China decreased from 11.1 to 6.7μgm-3 for SO42-,13.8-13.1μgm-3 for NO3-,7.4-5.8μgm-3 for NH4+,9.9-8.4μgm-3 for OM,4.6-3.8μg m-3 for BC and 12.9-9.6μg m-3 for other species in ***42-had the largest reduction of 40%,while NO3-had the lowest reduction of 5%,resulting in a greater fraction of NO3-and a smaller fraction of SO42-in *** the three key regions,Beijing-Tianjin-Hebei had the largest reduction in PM2.5 and its chemical *** decrease in SO42-concentrations was in line with the reduction of SO2 emissions,and the major driver of the SO2 emission reductions was the industrial *** decrease in NO3 concentrations was limited because the decrease in SO2 emissions and the stable NH3 emissions facilitated the formation of NO3-from HNO3,which partially offset the reduction in NOx emissions driven by the power *** mitigate PM2.5 pollution more effectively,future efforts are needed to reduce NH3 emissions.
Satellite derived NO2 column data have been used to study Chinese national fossil fuel consumption and pollutant *** on NO 2 retrievals from two satellites (GOME and SCIAMACHY) for 1996-2010,we analyzed the characteri...
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Satellite derived NO2 column data have been used to study Chinese national fossil fuel consumption and pollutant *** on NO 2 retrievals from two satellites (GOME and SCIAMACHY) for 1996-2010,we analyzed the characteristics and evolution of regional pollution related to NO x emissions in *** observations indicated that the highly polluted regions were *** emission dominated areas have expanded from the east to central and western China,and new highly polluted regions have formed throughout the ***-up emission estimates suggested a 133% increase in anthropogenic NOx emissions in East Central China during 1996 to 2010,which was lower than the 184% increase of the NO2 columns measured by the *** found that growth rates of NOx emissions have slowed in Chinese megacities over recent years,in contrast to which,the NOx emissions were soaring in medium-sized cities,indicating that strict controls of NOx emissions from coal-fired facilities are required in China.
A differential game guidance scheme with obstacle avoidance,based on the formulation of a combined linear quadratic and norm-bounded differential game,is designed for a three-player engagement scenario,which includes ...
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A differential game guidance scheme with obstacle avoidance,based on the formulation of a combined linear quadratic and norm-bounded differential game,is designed for a three-player engagement scenario,which includes a pursuer,an interceptor,and an *** confrontation between the players is divided into four phases(P1-P4)by introducing the switching time,and proposing different guidance strategies according to the phase where the static obstacle is located:the linear quadratic game method is employed to devise the guidance scheme for the energy optimization when the obstacle is located in the P1 and P3 stages;the norm-bounded differential game guidance strategy is presented to satisfy the acceleration constraint under the circumstance that the obstacle is located in the P2 and P4 ***,the radii of the static obstacle and the interceptor are taken as the design parameters to derive the combined guidance strategy through the dead-zone function,which guarantees that the pursuer avoids the static obstacle,and the interceptor,and attacks the ***,the nonlinear numerical simulations verify the performance of the game guidance strategy.
In recent years, researches on vocational skills are very extensive, most of them concentrated on vocational skills training, effect of vocational skill competition, vocational education and vocational skill identific...
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CO_(2)emission inventory provides fundamental data for climate research and emission ***,most global CO_(2)emission inventories were developed with energy statistics from International Energy Agency(IEA)and were avail...
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CO_(2)emission inventory provides fundamental data for climate research and emission ***,most global CO_(2)emission inventories were developed with energy statistics from International Energy Agency(IEA)and were available at country level with limited source ***,as the first step toward a high-resolution and dynamic updated global CO_(2)emission database,we developed a data-driven approach to construct seamless and highly-resolved energy consumption data cubes for 208 countries/territories,797 sub-country administrative divisions in 29 countries,42 fuel types,and 52 sectors,with the fusion of activity data from 24 international statistics and 65 regional/local *** CO_(2)emissions from fossil fuel combustion and cement production in 1970–2021 were then estimated with highly-resolved source category(1,484 of total)and sub-country information(797 of total).Specifically,73%of global CO_(2)emissions in 2021 were estimated with sub-country information,providing considerably improved spatial resolution for global CO_(2)emission *** the support of detailed information,the dynamics of global CO_(2)emissions across sectors and fuel types were presented,representing the evolution of global economy and progress of climate *** differences of sectoral contribution were found across sub-country administrative divisions within a given country,revealing the uneven distribution of energy and economic structure among different *** estimates were generally consistent with existing databases at aggregated level for global total or large emitters,while large discrepancies were observed for middle and small *** database,named the Multiresolution Emission Inventory model for Climate and air pollution research(MEIC)is publicly available through http://*** with highly-resolved information and timely update,which provides an independent carbon emission accounting data source for climate rese
Temporary social network has been a increasing popular field in the last few years where people form a temporary social group for a short time period with common interests or purposes in the same area. When a user att...
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In recent years, the development and deployment of the U.S. weapon equipment systems-of-systems (SoS) have yielded rich research results. However, there are still large gaps in the SoS development, joint testing, and ...
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