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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    

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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    

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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    

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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    

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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    

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Erratum to: On secondary new particle formation in China

Markku KULMAMA,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/s11783-016-0857-7

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Temporal evolution of charged and neutral nanoparticle concentrations during atmospheric new particle formation

E. Rohan Jayaratne, Buddhi Pushpawela, Lidia Morawska

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0862-x

摘要： Over 100 new particle formation events were studied. In 50 events, charged and neutral particles were not formed at the same time. In 42 of these events the charged particles formed before the neutral particles. Their subsequent growth rates were not determined by the particle charge. The result suggests that ion induced nucleation plays a role in particle formation. Time series of nanoparticle number concentration during new particle formation (NPF) events in the urban environment of Brisbane, Australia, showed that the formation of charged particles often occurred before that of neutral particles. We monitored 241 days during the calendar year 2012 over which NPF events were observed on 108 days. We studied the times at which the charged and neutral particle concentrations in the size range 1.8–3.2 nm reached their peak values and found that they were clearly different in 50 events with the peak neutral particle concentration lagging behind the charged particle concentration during 42 of these events with a mean time lag of 24±12 min. While the charged particles were more likely to form before the neutral particles, once formed, the growth rate of the particles did not depend on their charge. While ion-induced nucleation is not the dominant mechanism of NPF in the atmosphere, our observations suggest that the presence of ions in the atmosphere plays a role that cannot be ignored.

关键词： Charged particles     Cluster ions     Secondary particles     Environmental pollution    

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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    

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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    

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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    

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Two-echelon Emergency Response Problem and Simulation Considering Secondary Disasters

Han-peng Zhang,Yi Liao,Hui-xia Luo

《工程管理前沿（英文）》 2014年 第1卷 第3期   页码 318-321 doi: 10.15302/J-FEM-2014042

摘要： It is necessary for subsequent resource distribution planning that get expected relief time considering secondary disasters after natural disaster. The goal of this research is to develop a two-echelon emergency resource distribution model under condition of secondary disasters. Taking minimal maximize relief time as criterion of relief performance, we developed response strategies and simulation model to get the expected value. Numerical studies of this paper presented the result of response strategies.

关键词： simulation     secondary disasters     two-echelon vehicle routing model    

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PCDD/Fs emission, risk characterization, and reduction in China’s secondary copper production industry

Haiqian LI, Yonglong LU, Li LI

《环境科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 589-597 doi: 10.1007/s11783-013-0495-2

摘要： Secondary copper production is one of the key polychlorinated dibenzo- -dioxins and dibenzofurans (PCDD/Fs) emission sources in China, but research and data on this issue are rare. In 2004, when the Stockholm Convention entered into force in China, PCDD/Fs emissions from secondary copper production contributed to 32.2% of the total release. In this paper, PCDD/Fs emission dynamics from secondary copper industry were discussed and cumulative risks were characterized. From 2004 to 2009, industrial policies played an indirect role in PCDD/Fs reduction, but its effects are still limited. The Yangtze River Delta, Pearl River Delta and central regions were among the top three of dioxin emissions from secondary copper production in China. Shanghai, Shandong, Zhejiang, and Jiangxi had comparatively higher accumulated risk and were recommended as the priority regions for promoting PCDD/Fs emission control in China. From 2009 to 2015, the PCDD/Fs emission dynamics in the secondary copper industry were presented through simulation. PCDD/Fs emission equations were established, resulting in the recommendation of control technology conversion rate at 30% for small scale smelters and 51%–57% for large and medium-sized enterprises in 2015. In conclusion, both indirect policy and direct control technology retrofitting should be integrated for more effective PCDD/Fs emission reduction in secondary copper industry.

关键词： polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs)     secondary copper production     emission     risk     China    

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Effects of different doses of cadmium on secondary metabolites and gene expression in Artemisia annua

null

《医学前沿（英文）》 2017年 第11卷 第1期   页码 137-146 doi: 10.1007/s11684-016-0486-3

摘要：

This study aims to elucidate the underlying molecular mechanisms of artemisinin accumulation induced by cadmium (Cd). The effects of different Cd concentrations (0, 20, 60, and 120 μmol/L) on the biosynthesis of Artemisia annua L. were examined. Intermediate and end products were quantified by HPLC-ESI-MS/MS analysis. The expression of key biosynthesis enzymes was also determined by qRT-PCR. The results showed that the application of treatment with 60 and 120 μmol/L Cd for 3 days significantly improved the biosynthesis of artemisinic acid, arteannuin B, and artemisinin. The concentrations of artemisinic acid, arteannuin B, and artemisinin in the 120 μmol/L Cd-treated group were 2.26, 102.08, and 33.63 times higher than those in the control group, respectively. The concentrations of arteannuin B and artemisinin in 60 μmol/L Cd-treated leaves were 61.10 and 26.40 times higher than those in the control group, respectively. The relative expression levels of HMGR, FPS, ADS, CYP71AV1, DBR2, ALDH1, and DXR were up-regulated in the 120 μmol/L Cd-treated group because of increased contents of artemisinic metabolites after 3 days of treatment. Hence, appropriate doses of Cd can increase the concentrations of artemisinic metabolites at a certain time point by up-regulating the relative expression levels of key enzyme genes involved in artemisinin biosynthesis.

关键词： Cd     secondary metabolites     gene expressions     Artemisia annua L.    

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Simple model of sludge thickening process in secondary settlers

Yuankai ZHANG,Hongchen WANG,Lu QI,Guohua LIU,Zhijiang HE,Songzhu JIANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 319-326 doi: 10.1007/s11783-014-0758-6

摘要： In wastewater treatment plants (WWTPs), a secondary settler acts as a clarifier, sludge thickener, and sludge storage tank during peak flows and therefore plays an important role in the performance of the activated sludge process. Sludge thickening occurs in the lower portions of secondary clarifiers during their operation. In this study, by detecting the hindered zone from the complete thickening process of activated sludge, a simple model for the sludge thickening velocity, , describing the potential and performance of activated sludge thickening in the hindered zone was developed. However, sludge thickening in the compression zone was not studied because sludge in the compression zone showed limited thickening. This empirical model was developed using batch settling data obtained from four WWTPs and validated using measured data from a fifth WWTP to better study sludge thickening. To explore different sludge settling and thickening mechanisms, the curves of sludge thickening and sludge settling were compared. Finally, it was found that several factors including temperature, stirring, initial depth, and polymer conditioning can lead to highly concentrated return sludge and biomass in a biologic reactor.

关键词： wastewater treatment plants     secondary settler     sludge thickening     sludge settling     hindered zone    

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On the location of the secondary instantaneous poles in two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

《机械工程前沿（英文）》 2014年 第9卷 第1期   页码 34-40 doi: 10.1007/s11465-014-0290-1

摘要：

As the instant centers in planar mechanisms, the instantaneous poles (or instant poles, in brief) can be used for kinematic analysis in spherical mechanisms. One of the mandatory steps in this analysis is the determination of the location of these poles. This paper presents a theorem showing analytically that the locus of an unknown secondary instant pole in two-degree-of-freedom (2-DOF) spherical mechanisms is a great circle (GC). The exact location of the pole on its GC is obtained based on the configuration of the mechanism and velocity ratio of the two inputs. Moreover, using the results of the theorem, a geometrical technique is presented to determine the GC of the pole.

关键词： spherical mechanisms     instantaneous poles     great circle     angular velocity    

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标题 作者 时间 类型 操作

Formation of secondary inorganic aerosol in a frigid urban atmosphere

期刊论文

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

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

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

Erratum to: On secondary new particle formation in China

Markku KULMAMA,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

Temporal evolution of charged and neutral nanoparticle concentrations during atmospheric new particle formation

E. Rohan Jayaratne, Buddhi Pushpawela, Lidia Morawska

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

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

期刊论文

Physical and chemical processes of wintertime secondary nitrate aerosol formation

Qi YING

期刊论文

Two-echelon Emergency Response Problem and Simulation Considering Secondary Disasters

Han-peng Zhang,Yi Liao,Hui-xia Luo

期刊论文

PCDD/Fs emission, risk characterization, and reduction in China’s secondary copper production industry

Haiqian LI, Yonglong LU, Li LI

期刊论文

Effects of different doses of cadmium on secondary metabolites and gene expression in Artemisia annua

null

期刊论文

Simple model of sludge thickening process in secondary settlers

Yuankai ZHANG,Hongchen WANG,Lu QI,Guohua LIU,Zhijiang HE,Songzhu JIANG

期刊论文

On the location of the secondary instantaneous poles in two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

期刊论文