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Article ; Online: High-spatiotemporal-resolution mapping of PM2.5 traffic source impacts integrating machine learning and source-specific multipollutant indicator

Lingling Lv / Peng Wei / Jingnan Hu / Yangxi Chu / Xiao Liu

Environment International, Vol 183, Iss , Pp 108421- (2024)

2024

Abstract: Traffic sources are a major contributor to fine particulate matter (PM2.5) pollution, with their emissions and diffusion exhibiting complex spatiotemporal patterns. Receptor models have limitations in estimating high-resolution source contributions due ... ...

Abstract	Traffic sources are a major contributor to fine particulate matter (PM2.5) pollution, with their emissions and diffusion exhibiting complex spatiotemporal patterns. Receptor models have limitations in estimating high-resolution source contributions due to insufficient observation networks of PM2.5 compositions. This study developed a source apportionment method that integrates machine learning and emission-based integrated mobile source indicator (IMSI) to rapidly and accurately estimate PM2.5 traffic source impacts with high spatiotemporal resolution in the Beijing-Tianjin-Hebei region. Firstly, we utilized multisource data and developed various machine learning models to optimize the traffic-related pollutant concentration fields simulated by a chemical transport model. Results demonstrated that the Extreme Gradient Boosting (XGBoost) model exhibited excellent prediction accuracy of nitrogen oxide (NO2), carbon oxide (CO), and elemental carbon (EC), with the cross-validated R values increasing to 0.87–0.92 and error indices decreasing by 50–67%. Furthermore, we estimated and predicted daily mappings of PM2.5 traffic source impacts using the IMSI method based on optimized concentration fields, which improved spatially resolved source contributions to PM2.5. Our findings reveal that PM2.5 traffic source impacts display significant spatial heterogeneity, and these hotspots can be precisely identified during the pollution processes with sharp changes. The evaluation results indicated that there is a good correlation (R of 0.79) between PM2.5 traffic source impacts by IMSI method and traffic source contributions apportioned by a receptor model at Beijing site. Our study provides deeper insights of estimating the spatiotemporal distribution of PM2.5 source-specific impacts especially in regions without PM2.5 compositions, which can provide more complete and timely guidance to implement precise air pollution management strategies.
Keywords	Traffic source ; PM2.5 ; Source apportionment ; Machine learning ; Multipollutant indicator ; Environmental sciences ; GE1-350
Subject code	380
Language	English
Publishing date	2024-01-01T00:00:00Z
Publisher	Elsevier
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Identification of quality markers for Cyanotis arachnoidea and analysis of its physiological mechanism based on chemical pattern recognition, network pharmacology, and experimental validation

Jingnan Hu / Yu Feng / Baolin Li / Fengxia Wang / Qi Qian / Wei Tian / Liying Niu / Xinguo Wang

PeerJ, Vol 11, p e

2023 Volume 15948

Abstract: Cyanotis arachnoidea C. B. Clarke is a traditional Chinese medicinal herb that has a limited clinical use in the treatment of diabetes mellitus (DM) in minority areas of Guizhou in China. However, few prior reports are available on the quality control of ...

Abstract	Cyanotis arachnoidea C. B. Clarke is a traditional Chinese medicinal herb that has a limited clinical use in the treatment of diabetes mellitus (DM) in minority areas of Guizhou in China. However, few prior reports are available on the quality control of Cyanotis arachnoidea, and its quality markers and hypoglycemic mechanism are still unclear. The purpose of this study is to explore the quality markers (Q-markers) of Cyanotis arachnoidea and predict its hypoglycemic mechanism. In this study, ultra-high-performance liquid chromatography (UHPLC) fingerprint combined with chemical pattern recognition were performed, and four differential components were screened out as quality markers, including 20-Hydroxyecdysone, 3-O-acetyl-20-hydroxyecdysone, Ajugasterone C, and 2-O-acetyl-20-hydroxyecdysone. Network pharmacology analysis revealed 107 therapeutic target genes of Cyanotis arachnoidea in DM treatment, and the key targets were Akt1, TNF, IL-6, MAPK3, and JUN. The hypoglycemic mode of action of Cyanotis arachnoidea may be mediated by tumor necrosis factor (TNF) signaling, cancer, insulin resistance, and JAK-STAT pathways. Molecular docking analysis disclosed that the foregoing quality markers effectively bound their key target genes. An in vitro experiment conducted on pancreatic islet β-cells indicated that the forenamed active components of Cyanotis arachnoidea had hypoglycemic efficacy by promoting PI3K/Akt and inhibiting MAPK signaling. UHPLC also accurately quantified the quality markers. The identification and analysis of quality markers for Cyanotis arachnoidea is expected to provide references for the establishment of a quality control evaluation system and clarify the material basis and hypoglycemic mechanisms of this traditional Chinese medicine (TCM).
Keywords	Cyanotis arachnoidea ; Quality markers ; UHPLC ; Chemical pattern recognition ; Network pharmacology ; Hypoglycemic ; Medicine ; R ; Biology (General) ; QH301-705.5
Subject code	410
Language	English
Publishing date	2023-09-01T00:00:00Z
Publisher	PeerJ Inc.
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Efficient Catalysts of K and Ce Co-Doped LaMnO3 for NOx–Soot Simultaneous Removal and Reaction Kinetics

Li Yang / Jingnan Hu / Gang Tian / Jinwei Zhu / Qiang Song / Hongchang Wang / Chen Zhang

ACS Omega, Vol 6, Iss 30, Pp 19836-

2021 Volume 19845

Keywords	Chemistry ; QD1-999
Language	English
Publishing date	2021-07-01T00:00:00Z
Publisher	American Chemical Society
Document type	Article ; Online
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Article ; Online: Phytochemical Analysis Using UPLC-MS/MS Combined with Network Pharmacology Methods to Explore the Biomarkers for the Quality Control of Lingguizhugan Decoction

Baolin Li / Shuaishuai Fan / Jingnan Hu / Yongben Ma / Yu Feng / Fengxia Wang / Xinguo Wang / Liying Niu

Evidence-Based Complementary and Alternative Medicine, Vol

2021 Volume 2021

Abstract: As a classic TCM prescription, LGZG has been widely used in clinical prevention and treatment of heart failure, nonalcoholic fatty liver, and hyperlipidemia. However, there are few studies on chemical components in recent years, and the basis of quality ... ...

Abstract	As a classic TCM prescription, LGZG has been widely used in clinical prevention and treatment of heart failure, nonalcoholic fatty liver, and hyperlipidemia. However, there are few studies on chemical components in recent years, and the basis of quality evaluation is not sufficient. This study was to find the active ingredients of the Lingguizhugan decoction using UPLC-MS/MS and network pharmacology. By comparing the retention time and MS dates of the reference and self-building database, the cleavage rules of chemical composition whose mass errors are less than 1 ppm(FL less than 3 ppm) are analyzed. On this basis, a network pharmacology method was used to find biomarkers for quantitative analysis. The results show that 149 compounds were preliminaries identified or inferred, including 63 flavonoids, 30 triterpenes, 22 phenylpropanoids, 13 organic acids, 6 lactones, 5 alkaloids, 4 anthraquinones, and 6 other compounds. According to the network pharmacology results, 20 chemical constituents were selected as the biomarkers, which were determined simultaneously for the first time, including poricoic acid A, poricoic acid B, glycyrrhizic acid, glycyrrhetinic acid, liquiritin, isoliquiritin, liquiritigenin, isoliquiritin apioside, cinnamic acid, caffeic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isochlorogenic acid A, B, and C, atractylenolide I, II, and III, and coumarin. The methodological results show that the linearity, stability, precision, repeatability, and recovery of the method are satisfactory. Therefore, a comprehensive quality assessment system for LGZG was established on the basis of a systematic study of chemical substances and network pharmacology, which provided an important reference for the foundation of pharmacological action and its mechanics.
Keywords	Other systems of medicine ; RZ201-999
Subject code	540
Language	English
Publishing date	2021-01-01T00:00:00Z
Publisher	Hindawi Limited
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Non-negligible contributions to human health from increased household air pollution exposure during the COVID-19 lockdown in China

Yuqiang Zhang / Bin Zhao / Yueqi Jiang / Jia Xing / Shovan K. Sahu / Haotian Zheng / Dian Ding / Suzhen Cao / Licong Han / Cong Yan / Xiaoli Duan / Jingnan Hu / Shuxiao Wang / Jiming Hao

Environment International, Vol 158, Iss , Pp 106918- (2022)

2022

Abstract: Background: Ambient and household air pollution are found to lead to premature deaths from all-cause or cause-specific death. The national lockdown measures in China during COVID-19 were found to lead to abrupt changes in ambient surface air quality, but ...

Abstract	Background: Ambient and household air pollution are found to lead to premature deaths from all-cause or cause-specific death. The national lockdown measures in China during COVID-19 were found to lead to abrupt changes in ambient surface air quality, but indoor air quality changes were neglected. In this study, we aim to investigate the impacts of lockdown measures on both ambient and household air pollution as well as the short-term health effects of air pollution changes. Methods: In this study, an up-to-date emission inventory from January to March 2020 in China was developed based on air quality observations in combination with emission-concentration response functions derived from chemical transport modeling. These emission inventories, together with the emissions data from 2017 to 2019, were fed into the state-of-the-art regional chemistry transport model to simulate the air quality in the North China Plain. A hypothetical scenario assuming no lockdown effects in 2020 was also performed to determine the effects of the lockdown on air quality in 2020. A difference-to-difference approach was adopted to isolate the effects on air quality due to meteorological conditions and long-term decreasing emission trends by comparing the PM2.5 changes during lockdown to those before lockdown in 2020 and in previous years (2017–2019). The short-term premature mortality changes from both ambient and household PM2.5 changes were quantified based on two recent epidemiological studies, with uncertainty of urban and rural population migration considerations. Findings: The national lockdown measures during COVID-19 led to a reduction of 5.1 µg m−3 in ambient PM2.5 across the North China Plain (NCP) from January 25th to March 5th compared with the hypothetical simulation with no lockdown measures. However, a difference-to-difference method showed that the daily domain average PM2.5 in the NCP decreased by 9.7 µg m−3 between lockdown periods before lockdown in 2020, while it decreased by 7.9 µg m−3 during the same periods for ...
Keywords	Ambient Air pollution ; Household air pollution ; COVID-19 ; Mortality ; Environmental sciences ; GE1-350
Subject code	333
Language	English
Publishing date	2022-01-01T00:00:00Z
Publisher	Elsevier
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: Impact of emissions controls on ambient carbonyls during the Asia-Pacific Economic Cooperation summit in Beijing, China

Zhou, Xueming / Jihua Tan / Juanjuan Qin / Jingnan Hu / Jingchun Duan / Rongzhi Chen

Environmental science and pollution research international. 2019 Apr., v. 26, no. 12

2019

Abstract: Beijing and its surrounding areas implemented a series of stringent measures to ensure good air quality during the Asia-Pacific Economic Cooperation (APEC) summit. These measures included restrictions on traffic, constructions, and industrial activities. ...

Abstract	Beijing and its surrounding areas implemented a series of stringent measures to ensure good air quality during the Asia-Pacific Economic Cooperation (APEC) summit. These measures included restrictions on traffic, constructions, and industrial activities. The diurnal variations of carbonyls, 24-h PM₂.₅, and its chemical species were investigated before, during, after APEC, and the 2015 summer. The average concentrations of carbonyls, formaldehyde, acetaldehyde, and acetone were decreased by 65.2%, 78.6%, 41.5%, and 55.6% during APEC, respectively. The concentrations of propene equivalent, the ozone formation potential, and the contribution to OH· removal by carbonyls during APEC were approximately 27–33% of those during the preceding interval. The temporal variation of carbonyls during APEC was similar to that of other air pollutants, except for O₃; however, the diurnal variation of carbonyls was consistent with that of O₃, with the highest values at noon and the lowest ones at night during APEC. Large variations in C1/C2 (0.95–9.41) and C2/C3 (5.70–15.71) were observed during the sampling period. The correlations analysis, diagnostical ratios, and diurnal variations of carbonyls indicated that primary sources were not an important source and secondary formation was the dominant source of atmospheric carbonyls during the entire period. The control measures not only reduced primary carbonyl emissions but also dramatically reduced secondary carbonyl precursors, such as NOₓ and volatile organic compounds (VOCs), resulting in the low level of carbonyls during APEC. In addition, the potential health effects of carbonyls were evaluated and the cancer risk from formaldehyde and acetaldehyde was significantly higher before APEC than during the other intervals.
Keywords	acetaldehyde ; acetone ; air pollutants ; air pollution ; air quality ; chemical species ; control methods ; diurnal variation ; emissions ; formaldehyde ; health effects assessments ; hydroxyl radicals ; neoplasms ; nitrogen oxides ; ozone ; particulates ; propylene ; risk ; summer ; traffic ; volatile organic compounds ; China
Language	English
Dates of publication	2019-04
Size	p. 11875-11887.
Publishing place	Springer Berlin Heidelberg
Document type	Article
ZDB-ID	1178791-0
ISSN	1614-7499 ; 0944-1344
ISSN (online)	1614-7499
ISSN	0944-1344
DOI	10.1007/s11356-019-04577-5
Database	NAL-Catalogue (AGRICOLA)

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Article: Effects of aromatics, olefins and distillation temperatures (T50 & T90) on particle mass and number emissions from gasoline direct injection (GDI) vehicles

Zhu, Rencheng / Jingnan Hu / Lei Zu / Liqiang He / Xiaofeng Bao

Energy Policy. 2017 Feb., v. 101

2017

Abstract: Fuel quality is among the primary reasons for severe vehicle pollution. A limited understanding of the effects of gasoline properties on modern vehicle emissions is one obstacle for the establishment of stricter fuel standards in China. The goal of this ... ...

Abstract	Fuel quality is among the primary reasons for severe vehicle pollution. A limited understanding of the effects of gasoline properties on modern vehicle emissions is one obstacle for the establishment of stricter fuel standards in China. The goal of this study was to evaluate the effects of aromatic and olefin contents and T50 and T90 (defined as the 50%v and 90%v distillation temperatures) on tailpipe emissions from gasoline direct injection (GDI) vehicles compliant with China 4 standards. Both gaseous and particle emissions using different types of gasoline were measured. Changing aromatic and olefin contents had relatively small impacts on fuel consumption. Compared with olefins and T90, the regulated gaseous emissions were impacted more by aromatics and T50. Evident decreases of the particle mass (PM) and particle number (PN) emissions were noticed when the aromatic content and T90 decreased. Reducing the olefin content slightly decreased the PM emissions and increased the PN emissions. With decreasing T50, the PM emissions increased and the PN emissions slightly decreased. These results suggest that aromatic content and T90 should be decreased to reduce particle emissions from GDI vehicles. The information presented in this study provides some suggestions for how to improve gasoline quality in China.
Keywords	aromatic compounds ; distillation ; energy use and consumption ; gas emissions ; gasoline ; olefin ; particulate emissions ; pollution ; temperature ; China
Language	English
Dates of publication	2017-02
Size	p. 185-193.
Publishing place	Elsevier Ltd
Document type	Article
ISSN	0301-4215
DOI	10.1016/j.enpol.2016.11.022
Database	NAL-Catalogue (AGRICOLA)

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Article: Chemical characteristics and source apportionment of PM2.5 in Lanzhou, China

Tan, Jihua / Jingchun Duan / Jingnan Hu / Kebin He / Leiming Zhang / Xueming Zhou / Yan Li

Science of the total environment. 2017 Dec. 01, v. 601-602

2017

Abstract: Daily PM2.5 samples were collected during winter 2012 and summer 2013 at an urban site in Lanzhou and were analyzed for chemical compounds including water soluble inorganic ions (WSIN), trace elements, water soluble organic carbon (WSOC), carbonaceous ... ...

Abstract	Daily PM2.5 samples were collected during winter 2012 and summer 2013 at an urban site in Lanzhou and were analyzed for chemical compounds including water soluble inorganic ions (WSIN), trace elements, water soluble organic carbon (WSOC), carbonaceous species (OC/EC), polycyclic aromatic hydrocarbons (PAHs), and humic-like substances (HULIS). The seasonal-average reconstructed PM2.5 mass was 120.5Î¼gmâ3 in winter and 34.1Î¼gmâ3 in summer. The top three groups of species in PM2.5 were OC (35.4Â±13.9Î¼gmâ3), WSIN (34.89Â±14.21Î¼gmâ3), and EC (13.80Â±5.41Î¼gmâ3) in winter and WSIN (11.25Â±3.25Î¼gmâ3), OC (9.74Â±3.30Î¼gmâ3), and EC (4.44Â±2.00Î¼gmâ3) in summer. EC exceeded SO42â on most of the days. Several anthropogenic produced primary pollutants such as PAHs, Clâ, Pb, Cd and OCpri were 4â22 times higher in winter than summer. Carcinogenic substances such as Arsenic, BaP, Pb, and Cd in PM2.5 exceeded the WHO guideline limits by 274%, 153%, 23% and 7%, respectively. Positive Matric Factorization analysis identified seven source factors including steel industry, secondary aerosols, coal combustion, power plants, vehicle emissions, crustal dust, and smelting industry, which contributed 7.1%, 33.0%, 28.7%, 3.12%, 8.8%, 13.3%, and 6.0%, respectively, to PM2.5 in winter, and 6.7%, 14.8%, 3.1%, 3.4%, 25.2%, 11.6% and 35.2% in summer. Smelting industry and steel industry were identified for the first time as sources of PM2.5 in this city, and power plant was distinguished from industrial boiler and residential coal burning.
Keywords	aerosols ; arsenic ; burning ; cadmium ; carbon ; chlorides ; coal ; combustion ; dust ; guidelines ; industry ; inorganic ions ; lead ; particulate emissions ; particulates ; pollutants ; polycyclic aromatic hydrocarbons ; power plants ; steel ; sulfates ; summer ; winter ; World Health Organization ; China
Language	English
Dates of publication	2017-1201
Size	p. 1743-1752.
Publishing place	Elsevier B.V.
Document type	Article
ZDB-ID	121506-1
ISSN	1879-1026 ; 0048-9697
ISSN (online)	1879-1026
ISSN	0048-9697
DOI	10.1016/j.scitotenv.2017.06.050
Database	NAL-Catalogue (AGRICOLA)

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Article: Characteristics of volatile organic compounds (VOCs) from the evaporative emissions of modern passenger cars

Yue, Tingting / Fahe Chai / Jingnan Hu / Liqang He / Rencheng Zhu / Xin Yue / Yitu Lai

Atmospheric environment. 2017 Feb., v. 151

2017

Abstract: Volatile organic compounds (VOCs) from vehicle evaporative emissions contribute substantially to photochemical air pollution. Yet, few studies of the characteristics of VOCs emitted from vehicle evaporative emissions have been published. We investigate ... ...

Abstract	Volatile organic compounds (VOCs) from vehicle evaporative emissions contribute substantially to photochemical air pollution. Yet, few studies of the characteristics of VOCs emitted from vehicle evaporative emissions have been published. We investigate the characteristics of 57 VOCs in hot soak, 24 h diurnal and 48 h diurnal emissions by applying the Sealed Housing Evaporative Determination unit (SHED) test to three modern passenger cars (one US Tier 2 and two China IV vehicles) using two different types of gasoline. The characteristics of the VOCs from the hot soak, 24 h diurnal and 48 h diurnal emissions were different due to their different emission mechanisms. In the hot soak emissions, toluene, isopentane/n-pentane, and 2,2,4-trimethylpentane were dominant species. In the 24 h and 48 h diurnal emissions, isopentane and n-pentane were dominant species. Toluene was the third most dominant component in the 24 h diurnal emissions but decreased by a mass of 42%–80% in the 48 h diurnal emissions. In the hot soak, 24 h diurnal and 48 h diurnal emissions, alkanes were generally the dominant hydrocarbons, followed by aromatics and olefins. However, owing to different evaporative emission mechanisms, the weight percentages of the aromatic hydrocarbons decreased and the weight percentages of the alkanes increased from the hot soak test to the 24 h diurnal and 48 h diurnal tests for each vehicle. The dominant contributors to the ozone formation potentials (OFPs) were also different in the hot soak, 24 h diurnal and 48 h diurnal emissions. The OFPs (g O3/g VOC) of the hot soak emissions were higher than those of the 24 h and 48 h diurnal emissions. In addition, the combined effect of decreasing the olefin and aromatic contents of gasoline on vehicle evaporative emissions was investigated. The aromatics all decreased substantially in the hot soak, 24 h and 48 h diurnal emissions, and the total masses of the VOCs and OFPs decreased, with the greatest reduction occurring in the hot soak emissions when the fuel aromatic and olefin contents were reduced.
Keywords	air pollution ; alkenes ; automobiles ; emissions ; gasoline ; iso-octanes ; ozone ; pentane ; photochemistry ; toluene ; volatile organic compounds ; China ; United States
Language	English
Dates of publication	2017-02
Size	p. 62-69.
Publishing place	Elsevier Ltd
Document type	Article
ZDB-ID	216368-8
ISSN	0004-6981 ; 1352-2310
ISSN	0004-6981 ; 1352-2310
DOI	10.1016/j.atmosenv.2016.12.008
Database	NAL-Catalogue (AGRICOLA)

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Article: Real-world gaseous emissions of high-mileage taxi fleets in China

He, Liqiang / Jingnan Hu / Liuhanzi Yang / Zhenhua Li / Xuan Zheng / Shuxia Xie / Lei Zu / Junhui Chen / Yuan Li / Ye Wu

Science of the total environment. 2019 Apr. 01, v. 659

2019

Abstract: Mileage of taxi fleets is significantly higher than regular passenger vehicles in China, which might trigger greater tailpipe emissions of air pollutants. To investigate their real-world gaseous emissions, we applied portable emissions measurement ... ...

Abstract	Mileage of taxi fleets is significantly higher than regular passenger vehicles in China, which might trigger greater tailpipe emissions of air pollutants. To investigate their real-world gaseous emissions, we applied portable emissions measurement systems (PEMSs) to test 44 gasoline and 24 bi-fuel taxis in seven cities. Our real-world measurement results indicated that a major part of the tested China 3 and China 4 gasoline taxis, especially the samples with high mileage (>300,000 km), far exceeded the corresponding emission limits of NOX, THC and CO. Only the newest China 5 gasoline taxis with relatively lower mileage had effective emission controls and the gaseous emissions were below the limits. Illegal tampering, malfunction and deterioration of three-way catalytic converters (TWC) are major reasons for high emissions from high-mileage taxis. First, China 4 gasoline taxis without TWC (purposely removed by drivers) increased their gaseous emissions than TWC-equipped counterparts by more than one order of magnitude. Second, bi-fuel taxis when using compress natural gas (CNG) had much higher NOX and THC emissions than those when using gasoline, which might be probably attributed to unsophisticated engine calibration and unfavorable TWC working conditions. Furthermore, TWC renewal could bring immediate and substantial emission reductions (up to 70%) for high-mileage taxis. However, such benefits from TWC renewal would become less significant as the mileage levels further increase. We also found a good correlation between CO and THC emissions for gasoline taxis, whose cold start effects were both significant. This study poses significant concerns regarding real-world emissions of high-mileage taxi fleets in China, which could consist of many gross emitters in the urban areas. Stringent in-use compliance programs and in particular frequent TWC renewals for high-mileage taxis should be implemented by policy makers in China.
Keywords	air pollutants ; air pollution ; automobiles ; carbon monoxide ; cities ; cold ; compliance ; gas emissions ; gasoline ; issues and policy ; natural gas ; urban areas ; working conditions ; China
Language	English
Dates of publication	2019-0401
Size	p. 267-274.
Publishing place	Elsevier B.V.
Document type	Article
ZDB-ID	121506-1
ISSN	1879-1026 ; 0048-9697
ISSN (online)	1879-1026
ISSN	0048-9697
DOI	10.1016/j.scitotenv.2018.12.336
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