[Predictive Model for O in Shanghai Based on the KZ Filtering Technique and LSTM].

In this study, a Kolmogorov-Zurbenko （KZ） filter was proposed to decompose the original ozone （O） sequence to improve the accuracy of ozone long-term series prediction and select relevant meteorological features. Furthermore, the enhanced maximal minimal redundancy （mRMR） feature selection technique was combined with the support vector regression （SVR） approach to select the most illuminating meteorological features. Subsequently, from May to August 2023, during high ozone concentration periods, a long short-term memory network （LSTM） was utilized to assess and predict high ozone concentration periods at the monitoring stations of Jingan （urban area）, Pudong-Chuansha （suburban area）, and Dianshan Lake （suburban area） in Shanghai.

Quantitative impacts of meteorology and emissions on the long-term trend of O in the Yangtze River Delta (YRD), China from 2015 to 2022.

Extensive spatiotemporal analyses of long-trend surface ozone in the Yangtze River Delta (YRD) region and its meteorology-related and emission-related have not been systematically analyzed. In this study, by using 8-year-long (2015-2022) surface ozone observation data, we attempted to reveal the variation of multiple timescale components using the Kolmogorov-Zurbenko filter, and the effects of meteorology and emissions were quantitatively isolated using multiple linear regression with meteorological variables. The results showed that the short-term, seasonal, and long-term components accounted for daily maximum 8-hr average O (O) concentration, 46.

[Atmospheric Ozone Concentration Prediction in Nanjing Based on LightGBM].

Based on the air quality data and conventional meteorological data of the Nanjing Region from January 2015 to December 2016, to analyze the characteristics of O concentration changes in the Nanjing Region, a light gradient boosting machine (LightGBM) model was established to predict O concentration. The model was compared with three machine learning methods that are commonly used in air quality prediction, including support vector machine, recurrent neural network, and random forest methods, to verify its effectiveness and feasibility. Finally, the performance of the prediction model was analyzed under different meteorological conditions.

[Vertical Distribution Characteristics of Boundary Layer Volatile Organic Compounds in Autumn in the Mixed Industrial and Rural Areas over the Northern Suburb of Nanjing].

Based on the sounding data of VOCs in the lower troposphere (0-1000 m) in the northern suburb of Nanjing in the autumn of 2020, the vertical profile distribution, diurnal variation, and photochemical reactivity of VOCs in this area were analyzed. The results showed that the volume fraction of VOCs decreased with the increase in height (72.1×10±28.

[Characteristics and Health Risk Assessment of BTESX in the Northern Suburbs of Nanjing].

AMA GC5000BTX was used to monitor the mixing ratio of benzene, toluene, ethylbenzene, -xylene, -xylene, and styrene (BTESX) in the atmosphere of the northern suburb of Nanjing from January 2014 to December 2016. The temporal variation characteristics of BTESX and the influence of meteorological elements on it were analyzed, and the characteristic ratio method (T/B) was used to qualitatively analyze the source of BTESX. Finally, the human exposure analysis and evaluation method of EPA was used to evaluate the health risk of BTESX.

Reconciling the bottom-up methodology and ground measurement constraints to improve the city-scale NMVOCs emission inventory: A case study of Nanjing, China.

Reliable emission estimate of non-methane volatile organic compounds (NMVOCs) is important for understanding the atmospheric chemistry and formulating control policy of ozone (O). In this study, a speciated emission inventory of anthropogenic NMVOCs was developed with the refined "bottom-up" methodology and best available information of individual sources for Nanjing in 2017. The total NMVOCs emissions were calculated at 163.

[Size Distribution of Particulate Chemical Components in Nanjing Jiangbei New Area].

In order to explore the pollution characteristics of the chemical components of atmospheric particulate matter in Nanjing Jiangbei New Area, size-resolved samples were collected from 2013 to 2014. The size distribution and seasonal variation of the chemical components of the particles were studied. The results showed that the total concentration of nine water-soluble ions in fine particles was higher in autumn and winter than in spring and summer, while the concentration of coarse particles was highest in winter.

High-resolution anthropogenic ammonia emission inventory for the Yangtze River Delta, China.

The Yangtze River Delta (YRD) is one of the regions with air pollution and high ammonia (NH) emission in China. A high-resolution ammonia emission inventory for the YRD region was developed based on the updated source-specific emission factor (EFs) and the county-level activity data. The 1 × 1 km gridded emissions were allocated by using the appropriate spatial surrogate.

Characteristics of Volatile Organic Compounds in Nanjing and Suzhou, Two Urban Sites in the Yangtze River Delta, China.

A field measurement study of volatile organic compounds (VOCs) was performed in January 2015 in the urban areas of two of the most important cities of the Yangtze River Delta: Nanjing and Suzhou. The objectives of this study included comparing the characteristics of VOC concentrations, comparing the impacts of emissions on VOCs, using species ratios to assess air mass age, and evaluating ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAP) in air masses. The VOC concentrations in Nanjing (34.

[Urban Aerosol Hygroscopicity During Haze Weather].

The hygroscopicity of aerosols has an important influence on atmospheric visibility and is one of the main causes of haze pollution. Based on observations of the aerosol hygroscopic growth factor (GF), water soluble inorganic ions, and organic carbon/elemental carbon (OC/EC) data during haze weather from April 17 to May 21, in 2014, the hygroscopic properties of aerosols and corresponding effects on haze in Nanjing were analyzed. The results showed that the distribution of GF was bimodal and varied from 1.

Evolution of boundary layer ozone in Shijiazhuang, a suburban site on the North China Plain.

The structure of the boundary layer affects the evolution of ozone (O), and research into this structure will provide important insights for understanding photochemical pollution. In this study, we conducted a one-month observation (from June 15 to July 14, 2016) of the boundary layer meteorological factors as well as O and its precursors in Luancheng County, Shijiazhuang (37°53'N, 114°38'E). Our research showed that photochemical pollution in Shijiazhuang is serious, and the mean hourly maximum and mean 8-hr maximum O concentrations are 97.

PM vertical variation during a fog episode in a rural area of the Yangtze River Delta, China.

A dense radiation fog event occurred at the Shouxian site, Anhui Province, China, from the evening of January 2 to noon on January 3, 2017. During this event, vertical profiles of particulate matter (PM) and meteorological parameters within the lower troposphere (0-1000 m) were collected using a tethered balloon. This study assessed the evolution of the PM profile with the planetary boundary layer (PBL) structure and the effects of fog on the PM concentration.

[Application of Support Vector Machine Regression in Ozone Forecasting].

Support vector machine regression (SVMr) was proposed to forecast hourly ozone (O) concentrations, daily maximum O concentrations, and maximum 8 h moving average O concentrations (O 8 h) by employing the observations of meteorological variables and O and its precursors during the high O periods from May 20 to August 15, 2016 at an industrial area in Nanjing. The squared correlation coefficient () of the hourly O concentrations forecast was 0.84.

Spatial and seasonal characteristics of particulate matter and gaseous pollution in China: Implications for control policy.

By employing the air pollution data including particular matter (PM) and gaseous pollutants (SO, NO, CO, and O) measured over 130 cities in China from April 2014 to March 2015, the spatial and seasonal variations of air pollution are analyzed. The 9 representative regions including Beijing, Tianjin, and Hebei (BTH), Yangze River Delta (YRD), central China (CC), Sichuan Basin (SB), northeast China (NEC), northwest China (NWC), Pearl River Delta (PRD), Yungui Plateau (YP), and Tibet, are chose to quantify the conditions of PM and gaseous pollution. According to the magnitudes of PM from high to low, the regions are listed in sequence as BTH, CC, SB, YRD, NEC, NWC, PRD, YP, and Tibet.

Vertical distributions of black carbon aerosols over rural areas of the Yangtze River Delta in winter.

Based on a field campaign in Shouxian, a rural site on the Yangtze River Delta, China, from December 14, 2016 to January 4, 2017, the vertical profiles of black carbon (BC) and planetary boundary layer (PBL) structures were studied. In total, 58 vertical profiles were obtained, including of the PM, BC mass concentration (m) and relevant meteorological parameters. Four profile types were categorized: I: uniform vertical distributions (38%), II: higher values at lower altitudes (29%), III: bimodal distributions with high values near the ground and at higher altitudes (17%), and IV: unimodal distributions with high values at higher altitudes (11%).

[Characteristic Study on the "Weekend Effect" of Atmospheric O in Northern Suburb of Nanjing].

The data of ozone (O) and its precursors (NO, CO, VOCs) observed at northern suburb of Nanjing from December 01, 2013 to November 30, 2014 were used to analyze the difference of pollutant concentrations on weekends and weekdays, and its causes. The results showed that there was an obvious "Weekend Effect" in northern suburb of Nanjing. The mass concentrations of O on weekdays were higher than those on weekends, whereas mass concentrations of its precursors were higher on the weekends; The average mass concentrations of O were 19.

[Source Analysis of Volatile Organic Compounds in the Nanjing Industrial Area and Evaluation of Their Contribution to Ozone].

Ambient volatile organic compounds (VOCs) were continuously measured during the high ozone (O) periods from May 1 to May 31 and June 1 to July 16, 2015 at an industrial area in the north suburb of Nanjing. A positive matrix factorization (PMF) model and an observation-based model (OBM) were combined for the first time to investigate the contributions of VOC sources and species to local photochemical O formation. The average VOC concentrations in 2014 and 2015 were (36.

[Aerosol Chemical Characteristics for Different Air Pollution Levels in North Suburban Nanjing].

PMsamples were collected in a northern suburb of Nanjing during the winter of 2015. Water soluble ions and carbonaceous substances under different air quality levels were analyzed by an 850 professional IC-type ion chromatograph produced by Metrohm and a Model 2001A carbon analyzer. The results show that the average mass concentration of PM, SO, NO, and NH during heavy pollution days was 4.

Seasonal Variation in Water-Soluble Ions in Airborne Particulate Deposition in the Suburban Nanjing Area, Yangtze River Delta, China, During Haze Days and Normal Days.

To investigate the seasonal variation and characterization of water-soluble ions (WSIs) present in airborne particle deposition (APD) during Haze Days (visibility ≤7.5 km) and Normal Days (visibility >7.5 km) in suburban Nanjing area, 151 filter samples were collected from 18 May 2013 to 26 May 2014.

[Modeled Deposition of Fine Particles in Human Airway in Northern Suburb of Nanjing].

The particles number concentrations were determined by Wide-range Particle Spectrometer (WPS) in northern suburb of Nanjing in January and April 2015. The information of size distributions was applied in the multiple-path particle dosimetry model (MPPD) v.3.

[Estimating the Secondary Organic Aerosol Concentration and Source Apportionment During the Summer and Winter in the Nanjing Industrial District].

Volatile organic compounds (VOCs) were determined by GC5000, an automatic on-line Gas Chromatography-Flame Ionization Detector. Elemental carbon (EC) and organic carbon (OC) were determined by the thermal/optical method using DRI-2001A during the periods of June 15-July 15 2015 and December 16 2015-January 15 2016. The concentration of secondary organic aerosol(SOA) was estimated by fractional aerosol coefficients (FAC) and EC tracer method.

Source Apportionment of Volatile Organic Compounds in an Urban Environment at the Yangtze River Delta, China.

Volatile organic compounds (VOCs) were collected continuously during June-August 2013 and December 2013-February 2014 at an urban site in Nanjing in the Yangtze River Delta. The positive matrix factorization receptor model was used to analyse the sources of VOCs in different seasons. Eight and seven sources were identified in summer and winter, respectively.

[Variation Characteristics and Health Risk Assessment of BTEX in the Atmosphere of Northern Suburb of Nanjing].

BTEX concentrations were determined by GC5000 online gas chromatography in the atmosphere of the north suburb of Nanjing in March 2013 to February 2014, using the EPA human exposure analysis evaluation method for benzene series compounds of volatile organic compounds (VOCs) in health risk assessment. The results showed that the total amount of BTEX showed the variation characteristics of spring > winter > autumn > summer. BTEX concentration was higher in the periods of 07:00-10:00 and 17:00-20:00, and the lowest was detected between 13:00-15:00; At the weekend, the concentration of BTEX was higher than on the working day.

[Source Apportionment of Volatile Organic Compounds and Health Assessment of Benzene Series in Northern Suburb of Nanjing in Winter].

Volatile organic compounds (VOCs) in the atmosphere of the north suburb of Nanjing in December 2015 were determined by GC5000 online gas chromatography,and the main composition and characteristics of VOCs were analyzed by using the PMF receptor model sources of VOCs parsing.The United States Environmental Protection Agency (EPA) human exposure analysis and evaluation method in the United States were used to evaluate Human health risk of benzene series.The results showed that there were 6 sources in the PMF mode.

[Distribution Characteristics of Water Soluble Ions Under Different Weather Conditions During the Youth Olympic Games in Nanjing].

To study the variation characteristics of water soluble ions during youth Olympic Games, PM and water soluble ions were observed by using the beta dust instrument, Anderson 9th sampler and IC type ion chromatography analyzer from August 6 to September 4, 2014. The observations were divided into three types of weather, sunny, rainy and cloudy. The average concentrations of PM under different weather conditions were sunny > cloudy > rainy days.