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Effects of two transition metal sulfate salts on secondary organic aerosol formation in toluene/NO

Biwu CHU, Jiming HAO, Junhua LI, Hideto TAKEKAWA, Kun WANG, Jingkun JIANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 1-9 doi: 10.1007/s11783-012-0476-x

摘要: Aerosol phase reactions play a very important role on secondary organic aerosol (SOA) formation, and metal-containing aerosols are important components in the atmosphere. In this study, we tested the effects of two transition metal sulfate salts, manganese sulfate (MnSO ) and zinc sulfate (ZnSO ), on the photochemical reactions of a toluene/NO photooxidation system in a 2 m smog chamber. By comparing photochemical reaction products of experiments with and without transition metal sulfate seed aerosols, we evaluated the effects of transition metal sulfate seed aerosols on toluene consumption, NO conversion and the formation of ozone and SOA. MnSO and ZnSO seed aerosols were found to have similar effects on photochemical reactions, both enhance the SOA production, while showing negligible effects on the gas phase compounds. These observations are consistent when varying metal sulfate aerosol concentrations. This is attributed to the catalytic effects of MnSO and ZnSO seed aerosols which may enhance the formation of condensable semivolatile compounds. Their subsequent partitioning into the aerosol phase leads to the observed SOA formation enhancement.

关键词: manganese sulfate     zinc sulfate     seed aerosols     toluene photooxidation     secondary organic aerosol    

Response of organic aerosol characteristics to emission reduction in Yangtze River Delta region

《环境科学与工程前沿(英文)》 2023年 第17卷 第9期 doi: 10.1007/s11783-023-1714-0

摘要:

● The emission reduction causes significant change in organic aerosol composition.

关键词: Emission control     Secondary organic aerosol     Atmospheric oxidizing capacity     Holiday effects     COVID-19 lockdown    

Physical and chemical processes of wintertime secondary nitrate aerosol formation

Qi YING

《环境科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 348-361 doi: 10.1007/s11783-011-0343-1

摘要: The UCD/CIT model was modified to include a process analysis (PA) scheme for gas and particulate matter (PM) to study the formation of secondary nitrate aerosol during a stagnant wintertime air pollution episode during the California Regional PM /PM Air Quality Study (CRPAQS) where detailed measurements of PM components are available at a few sites. Secondary nitrate is formed in the urban areas from near the ground to a few hundred meters above the surface during the day with a maximum modeled net increase rate of 4 μg·m ·d during the study episode. The secondary nitrate formation rate in rural areas is lower due to lower NO . In the afternoon hours, near-surface temperature can be high enough to evaporate the particulate nitrate. In the nighttime hours, both the gas phase N O reactions with water vapor and the N O heterogeneous reactions with particle-bound water are important for secondary nitrate formation. The N O reactions are most import near the surface to a few hundred meters above surface with a maximum modeled net secondary nitrate increase rate of 1 μg·m ·d and are more significant in the rural areas where the O concentrations are high at night. In general, vertical transport during the day moves the nitrate formed near the surface to higher elevations. During the stagnant days, process analysis indicates that the nitrate concentration in the upper air builds up and leads to a net downward flux of nitrate through vertical diffusion and a rapid increase of surface nitrate concentration.

关键词: secondary nitrate aerosol     N2O5 heterogeneous reaction     process analysis    

Formation of secondary inorganic aerosol in a frigid urban atmosphere

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1452-0

摘要:

•Harbin showed relatively high threshold RH (80%) for apparent increase of SOR.

关键词: Haze     Sulfate     Nitrate     Heterogeneous chemistry     Biomass burning     Northeast China    

Screening the emission sources of volatile organic compounds (VOCs) in China by multi-effects evaluation

He NIU,Ziwei MO,Min SHAO,Sihua LU,Shaodong XIE

《环境科学与工程前沿(英文)》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0828-z

摘要: We develop a multi-effect evaluation method to assess integrated impact of VOCs. Enable policy-makers to identify important emission sources, regions, and key species. Solvent usage and industrial process are the most important anthropogenic sources. Styrene, toluene, ethylene, benzene, and m/p-xylene are key species to be cut. Volatile organic compounds (VOCs) play important roles in the atmosphere via three main pathways: photochemical ozone formation, secondary organic aerosol production, and direct toxicity to humans. Few studies have integrated these effects to prioritize control measures for VOCs sources. In this study, we developed a multi-effects evaluation methodology based on updated emission inventories and source profiles, by combining the ozone formation potential (OFP), secondary organic aerosol potential (SOAP), and VOC toxicity data. We derived species-specific emission inventories for 152 sources. The OFPs, SOAPs, and toxicity of each source were estimated, the contribution and sharing of source to each of these adverse effects were calculated. Weightings were given to the three adverse effects by expert scoring, and then the integrated effect was determined. Taking 2012 as the base year, solvent use and industrial process were found to be the most important anthropogenic sources, accounting for 24.2% and 23.1% of the integrated effect, respectively, followed by biomass burning, transportation, and fossil fuel combustion, each had a similar contribution ranging from 16.7% to 18.6%. The top five industrial sources, including plastic products, rubber products, chemical fiber products, the chemical industry, and oil refining, accounted for nearly 70.0% of industrial emissions. Beijing, Chongqing, Shanghai, Jiangsu, and Guangdong were the five provinces contributing the largest integrated effects. For the VOC species from emissions showed the largest contributions were styrene, toluene, ethylene, benzene, and m/p-xylene.

关键词: Ozone formation     Secondary organic aerosol     Multi-effects evaluation     VOC abatement strategy    

Secondary aerosol formation in winter haze over the Beijing-Tianjin-Hebei Region, China

Dongjie Shang, Jianfei Peng, Song Guo, Zhijun Wu, Min Hu

《环境科学与工程前沿(英文)》 2021年 第15卷 第2期 doi: 10.1007/s11783-020-1326-x

摘要: Abstract • Characteristics and interannual variation of aerosol pollution are illustrated. • Mechanisms of secondary aerosol formation in winter haze of North China are reviewed. • Directions in future studies of secondary aerosol formation are provided. Severe haze pollution occurs frequently in the winter over the Beijing-Tianjin-Hebei (BTH) region (China), exerting profound impacts on air quality, visibility, and human health. The Chinese Government has taken strict mitigation actions since 2013 and has achieved a significant reduction in the annual mean PM2.5 concentration over this region. However, the level of secondary aerosols during heavy haze episodes showed little decrease during this period. During heavy haze episodes, the concentrations of secondary aerosol components, including sulfate, nitrate and secondary organics, in aerosol particles increase sharply, acting as the main contributors to aerosol pollution. To achieve effective control of particle pollution in the BTH region, the precise and complete secondary aerosol formation mechanisms have been investigated, and advances have been made about the mechanisms of gas phase reaction, nucleation and heterogeneous reactions in forming secondary aerosols. This paper reviews the research progress in aerosol chemistry during haze pollution episodes in the BTH region, lays out the challenges in haze formation studies, and provides implications and directions for future research.

关键词: Secondary aerosol formation     Regional haze     Photochemical reaction     Aqueous reaction     Chemical mechanism    

Size-resolved aerosol ionic composition and secondary formation at Mount Heng in South Central China

Xinfeng WANG, Wenxing WANG, Likun XUE, Xiaomei GAO, Wei NIE, Yangchun YU, Yang ZHOU, Lingxiao YANG, Qingzhu ZHANG, Tao WANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第6期   页码 815-826 doi: 10.1007/s11783-013-0503-6

摘要: To understand the size-resolved aerosol ionic composition and the factors influencing secondary aerosol formation in the upper boundary layer in South Central China, size-segregated aerosol samples were collected using a micro-orifice uniform deposit impactor (MOUDI) in spring 2009 at the summit of Mount Heng (1269 m asl), followed by subsequent laboratory analyses of 13 inorganic and organic water-soluble ions. During non-dust-storm periods, the average PM concentration was 41.8 μg·m , contributing to 55% of the PM . Sulfates, nitrates, and ammonium, the dominant ions in the fine particles, amounted to 46.8% of the PM . Compared with Mount Tai in the North China Plain, the concentrations of both fine and coarse particles and the ions contained therein were substantially lower. When the air masses from Southeast Asia prevailed, intensive biomass burning there led to elevated concentrations of sulfates, nitrates, ammonium, potassium, and chloride in the fine particles at Mount Heng. The air masses originating from the north Gobi brought heavy dust storms that resulted in the remarkable production of sulfates, ammonium, methane sulfonic acid, and oxalates in the coarse particles. Generally, the sulfates were primarily produced in the form of (NH ) SO in the droplet mode via heterogeneous aqueous reactions. Only approximately one-third of the nitrates were distributed in the fine mode, and high humidity facilitated the secondary formation of fine nitrates. The heterogeneous formation of coarse nitrates and ammonium on dry alkaline dust surfaces was found to be less efficient than that on the coarse particles during non-dust-storm periods.

关键词: aerosol water-soluble ions     size distributions     secondary formation     dust storm     Mount Heng    

Mechanisms for simultaneous ozonation of sulfamethoxazole and natural organic matters in secondary effluent

《环境科学与工程前沿(英文)》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1368-0

摘要:

• SMX was mainly degraded by hydrolysis, isoxazole oxidation and double-bond addition.

关键词: Sulfamethoxazole     Ozonation     Natural organic matters     Secondary effluent     Degradation mechanism    

Effects of seed particles Al

Xiao Zhang, Biwu Chu, Junhua Li, Chaozhi Zhang

《环境科学与工程前沿(英文)》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0936-4

摘要: Seed particles Al O , Al (SO ) and H SO were selected to investigate their effects on secondary aerosol (SA) formation in toluene/NO photooxidation under sulfur dioxide (SO ) and ammonia (NH ). Effect of seed particles on SA formation was related to their acid-base properties and the presence of acid or alkaline gases. Under NH -poor condition, SA formation increased with increasing SO concentration due to the acid-catalyzing effect of the oxidation products of SO (i.e. H SO ). The enhancing effect of SO became unobvious under NH -rich condition, because NH would eliminate the acid-catalyzing effect by neutralizing the acid products. Acidic seeds H SO accelerated SA formation under either SO or NH condition. Weak acidic Al (SO ) seeds didn’t affect obviously on SA formation. The inhibiting effect of amphoteric seeds Al O on SA formation was related to the presence of SO / NH due to their acid-base property. Under NH -poor condition, the inhibiting effect of Al O on SA formation decreased with increasing concentration of SO , while under NH -rich condition, the inhibiting effect wasn’t remarkable.

关键词: Seed particle     Secondary aerosol     Sulfur dioxide     Ammonia     Acid-catalyzing effect    

Effects of Co2+ on the erythromycin biosynthesis

DU Wen, CHEN Changhua

《化学科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 246-250 doi: 10.1007/s11705-007-0044-2

摘要: Erythromycin biosynthesis is a highly complicated process, which involves both primary metabolism and secondary metabolism. The specific activities of the key enzymes related to glucose metabolism such as hexose kinase (HK), glucose-6-phosphate dehydrogenase (6-PDH), phosphofructokinase (PFK), and isocitrate dehydrogenase (ICD), were determined in . The specific activities of the enzymes involved in secondary metabolism, such as methylmalonyl-coenzyme A mutase (MCM) and methylmalonyl-coenzyme A transcarboxylase (MCT), were detected as well. Some organic acids contained in fermentation broth were also analyzed. The results show that Co is able to increase erythromycin biosynthesis. It maybe due to Co improving the specific activities of methylmalonyl-coenzyme A mutase and methylmalonyl-coenzyme A transcarboxylase. Meanwhile, it also enhances the flux of the glucose metabolism pathway.

关键词: secondary metabolism     organic     fermentation     process     phosphofructokinase    

Organic nitrogen in PM

Qian ZHANG,Fengkui DUAN,Kebin HE,Yongliang MA,Haiyan LI,Takashi KIMOTO,Aihua ZHENG

《环境科学与工程前沿(英文)》 2015年 第9卷 第6期   页码 1004-1014 doi: 10.1007/s11783-015-0799-5

摘要: Nitrogenous species, as important chemical components in PM , include organic nitrogen (ON) and inorganic nitrogen (IN), both of which have potential effects on human health, climate change and visibility degradation. In this study, we analyzed total nitrogen (TN) by CHN Elemental analyzer and inorganic nitrogen by ion chromatography (IC) respectively to obtain ON by calculating the difference between TN and IN. The results show that the mean ON concentrations in winter and summer are both 2.86 μg·m , ten times higher than other places reported on average. ON contributes about 20%–30% to TN on average in both seasons, presenting higher contribution in summer. N:C ratios are much higher in summer than winter. ON sources or formation were strengthened by heavy PM pollution loads, especially sensitive to sulfate. ON concentrations are higher at night in the both seasons, however with distinguished day and night difference patterns influenced by relative humidity (RH) conditions. In winter, ON concentrations increase with RH on average through low RH values to high RH values. The variations are far larger than the ones caused by day and night difference. However in summer, day and night difference dominates the variations of ON concentrations at low RH values, and RH conditions promote ON concentrations increase significantly only at high RH values. Dust related source and anthropogenic emission related secondary source are identified as important sources for ON. At heavy pollution loads, ON sources are more of secondary formation, possibly strengthened by combination influence of RH and acidity increase.

关键词: organic nitrogen     N:C ratio     secondary     day and night variation     relative humidity (RH)     acidity    

On secondary new particle formation in China

Markku Kulmala,Tuukka Petäjä,Veli-Matti Kerminen,Joni Kujansuu,Taina Ruuskanen,Aijun Ding,Wei Nie,Min Hu,Zhibin Wang,Zhijun Wu,Lin Wang,Douglas R. Worsnop

《环境科学与工程前沿(英文)》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0850-1

摘要: Formation of new atmospheric aerosol particles is a global phenomenon that has been observed to take place in even heavily-polluted environments. In China, new particle production has been observed at very high pollution levels (condensation sink about 0.1s ) in several megacities. A holistic scientific understanding on the atmospheric phenomena associated with air quality as a whole, as well as on the connection between air quality and climate, is lacking at the moment.With a network of observation stations, we will be able to understand the interactions and feedbacks associated with the urban pollution mixture, and ultimately, are ready to make targeted strategies for the pollution control. This paper summaries the recent advances in studying secondary new aerosol formation in China and shows how increased process-level understanding will help us to understand air quality-climate-weather interactions and how the feedbacks and interactions affect the air quality in highly-polluted environments such as those frequently encountered in Chinese megacities. Formation of new atmospheric aerosol particles is a global phenomenon that has been observed to take place in even heavily-polluted environments. However, in all environments there appears to be a threshold value of the condensation sink (due to pre-existing aerosol particles) after which the formation rate of 3 nm particles is no longer detected. In China, new particle production has been observed at very high pollution levels (condensation sink about 0.1 s ) in several megacities, including Beijing, Shanghai and Nanjing as well as in Pearl River Delta (PRD). Here we summarize the recent findings obtained from these studies and discuss the various implications these findings will have on future research and policy.

关键词: Aerosol particles     Heavily-polluted environments     Condensation sink     New particle production     Megacities    

Characterization of submicron aerosols in the urban outflow of the central Pearl River Delta region of China

Zhaoheng GONG, Zijuan LAN, Lian XUE, Liwu ZENG, Lingyan HE, Xiaofeng HUANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第5期   页码 725-733 doi: 10.1007/s11783-012-0441-8

摘要: Submicron aerosol particles (with aerodynamic diameters less than 1 μm, PM ) were sampled and measured in Heshan, an urban outflow site of Guangzhou megacity in Pearl River Delta in South China, using an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) in November 2010 during 2010 Guangzhou Asian Games. The mean PM mass concentration measured was 47.9±17.0 μg·m during the campaign, with organic aerosol (OA) and sulfate being the two dominant species, accounting for 36.3% and 20.9% of the total mass, respectively, followed by black carbon (17.1%, measured by an aethalometer), nitrate (12.9%), ammonium (9.6%) and chloride (3.1%). The average size distributions of the species (except black carbon) were dominated by an accumulation mode peaking at ~550 nm. Calculations based on high-resolution organic mass spectrum showed that, C, H, O and N on average contributed 58.1%, 7.3%, 30.7%, and 3.9% to the total organic mass, respectively. The average ratio of organic mass over organic carbon mass (OM/OC) was 1.73±0.08. Four components of OA were identified by the Positive Matrix Factorization (PMF) analysis, including a hydrocarbon-like (HOA), a biomass burning (BBOA) and two oxygenated (SV-OOA and LV-OOA) organic aerosol components, which on average accounted for 18.0%, 14.3%, 28.8% and 38.9% of the total organic mass, respectively.

关键词: organic aerosol     high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS)     positive matrix factorization    

Computational fluid dynamics simulation of aerosol transport and deposition

Yingjie TANG, Bing GUO

《环境科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 362-377 doi: 10.1007/s11783-011-0365-8

摘要: In this article computational fluid dynamics (CFD) simulation of aerosol transport and deposition, i.e. the transport and deposition of particles in an aerosol, is reviewed. The review gives a brief account of the basics of aerosol mechanics, followed by a description of the general CFD approach for flow field simulation, turbulence modeling, wall treatments and simulation of particle motion and deposition. Then examples from the literature are presented, including CFD simulation of particle deposition in human respiratory tract and particle deposition in aerosol devices. CFD simulation of particle transport and deposition may provide information that is difficult to obtain through physical experiments, and it may help reduce the number of experiments needed for device design. Due to the difficulty of describing turbulent flow and particle-eddy interaction, turbulent dispersion of particles remains one of the greatest challenges for CFD simulation. However, it is possible to take a balanced approach toward quantitative description of aerosol dispersion using CFD simulation in conjunction with empirical relations.

关键词: computational fluid dynamics (CFD)     aerosol     transport     deposition    

Calculation of collision frequency function for aerosol particles in free molecule regime in presence

Xiaowei LUO, Yannick BENICHOU, Suyuan YU

《能源前沿(英文)》 2013年 第7卷 第4期   页码 506-510 doi: 10.1007/s11708-013-0275-5

摘要: The collision frequency function for aerosol particles has already been calculated for the free molecule regime and for the continuum range. The present work, taking into account the influence of internal force fields such as magnetic force, electric force and molecular forces, created by particles themselves, recalculated the collision frequency in the case of particles much smaller than the mean free path of the gas (free molecule regime). Attractive forces increase naturally the collision frequency, while repulsive forces decrease it. The calculation was performed for all types of central forces deriving from a potential, including Coulomb forces and Van der Waals forces.

关键词: aerosol particles     collision frequency function     coagulation    

标题 作者 时间 类型 操作

Effects of two transition metal sulfate salts on secondary organic aerosol formation in toluene/NO

Biwu CHU, Jiming HAO, Junhua LI, Hideto TAKEKAWA, Kun WANG, Jingkun JIANG

期刊论文

Response of organic aerosol characteristics to emission reduction in Yangtze River Delta region

期刊论文

Physical and chemical processes of wintertime secondary nitrate aerosol formation

Qi YING

期刊论文

Formation of secondary inorganic aerosol in a frigid urban atmosphere

期刊论文

Screening the emission sources of volatile organic compounds (VOCs) in China by multi-effects evaluation

He NIU,Ziwei MO,Min SHAO,Sihua LU,Shaodong XIE

期刊论文

Secondary aerosol formation in winter haze over the Beijing-Tianjin-Hebei Region, China

Dongjie Shang, Jianfei Peng, Song Guo, Zhijun Wu, Min Hu

期刊论文

Size-resolved aerosol ionic composition and secondary formation at Mount Heng in South Central China

Xinfeng WANG, Wenxing WANG, Likun XUE, Xiaomei GAO, Wei NIE, Yangchun YU, Yang ZHOU, Lingxiao YANG, Qingzhu ZHANG, Tao WANG

期刊论文

Mechanisms for simultaneous ozonation of sulfamethoxazole and natural organic matters in secondary effluent

期刊论文

Effects of seed particles Al

Xiao Zhang, Biwu Chu, Junhua Li, Chaozhi Zhang

期刊论文

Effects of Co2+ on the erythromycin biosynthesis

DU Wen, CHEN Changhua

期刊论文

Organic nitrogen in PM

Qian ZHANG,Fengkui DUAN,Kebin HE,Yongliang MA,Haiyan LI,Takashi KIMOTO,Aihua ZHENG

期刊论文

On secondary new particle formation in China

Markku Kulmala,Tuukka Petäjä,Veli-Matti Kerminen,Joni Kujansuu,Taina Ruuskanen,Aijun Ding,Wei Nie,Min Hu,Zhibin Wang,Zhijun Wu,Lin Wang,Douglas R. Worsnop

期刊论文

Characterization of submicron aerosols in the urban outflow of the central Pearl River Delta region of China

Zhaoheng GONG, Zijuan LAN, Lian XUE, Liwu ZENG, Lingyan HE, Xiaofeng HUANG

期刊论文

Computational fluid dynamics simulation of aerosol transport and deposition

Yingjie TANG, Bing GUO

期刊论文

Calculation of collision frequency function for aerosol particles in free molecule regime in presence

Xiaowei LUO, Yannick BENICHOU, Suyuan YU

期刊论文