[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.

[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.

[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.

[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.

[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.

[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.

[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.

[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.

[Contributions of Factors That Influenced the Visibility In North Suburb of Nanjing In Winter and Spring].

The data of visibility, relative humidity (RH), temperature (T), concentrations and chemical compositions of particles from January to May in 2014 were analyzed to understand the effects of meteorological elements and aerosols on the visibility in north suburb of Nanjing, research the contributions of different aerosol chemical compositions to extinction coefficients and propose the visibility fitting solutions of this region based on different parameters. As the results showed, the average visibility during the observation period was (5.78 ± 3.

[Characteristics of Winter Atmospheric Mixing Layer Height in Beijing-Tianjin-Hebei Region and Their Relationship with the Atmospheric Pollution].

Atmospheric mixing layer height (MLH) is one of the main factors affecting the atmospheric diffusion and plays an important role in air quality assessment and distribution of the pollutants. Based on the ceilometers data, this paper has made synchronous observation on MLH in Beijing-Tianjin-Hebei region (Beijing, Tianjin, Shijiazhuang and Qinhuangdao) in heavy polluted February 2014 and analyzed the respective overall change and its regional features. Results show that in February 2014,the average of mixing layer height in Qinhuangdao is the highest, up to 865 +/- 268 m, and in Shijiazhuang is the lowest (568 +/- 207 m), Beijing's and Tianjin's are in between, 818 +/- 319 m and 834 +/- 334 m respectively; Combined with the meteorological data, we find that radiation and wind speed are main factors of the mixing layer height; The relationship between the particle concentration and mixing layer height in four sites suggests that mixing layer is less than 800 m, concentration of fine particulate matter in four sites will exceed the national standard (GB 3095-2012, 75 microg x m(-3)).

[Characteristics and source apportionment of volatile organic compounds (VOCs) in the northern suburb of Nanjing].

Based on the data of volatile organic compounds (VOCs) collected continuously from 1st Mar, 2011 to 29th Feb, 2012 in the northern suburb of Nanjing, characteristics of their variability, differences of ratios of tracers and source apportionment by principal component analysis/absolute principal component scores (PCA/APCS) were analyzed. The results showed that the total VOCs mixing ratios were 43.52 x 10(-9), which accounted for 45.

[Distribution characteristics of pollution gases and water soluble ion in aerosol during the Asian Youth Games of Nanjing, China].

Water soluble ions were observed by an Andersen cascade impactor (Andersen) and ion chromatography in Nanjing during the Asian Youth Games (AYG), and PM2.5, NO, NO2, O3 and CO were observed by ray β dust instrument, EMS pollution gases monitoring system. Concentrations of PM2.

[Variation characteristics of surface ozone and its precursors during summertime in Nanjing northern suburb].

It is not optimistic about current air quality in Nanjing northern suburb, an area with the agglomeration of heavy industry such as steel-making and petrochemical industry. Measurement of ozone and its precursors conducted from May 18th to August 31st, with the Meteorological data recorded simultaneously, were analyzed to characterize the local photochemical pollution in summertime. The results showed that the average volume fraction of ozone (O3), nitrogen oxide (NO(x)) and volatile organic compounds (VOCs) in Nanjing northern suburb was about (32.

[Size distribution and characterization of OC and EC in atmospheric aerosols during the Asian Youth Games of Nanjing, China].

Aerosol samples were collected by an Andersen cascade impactor (Andersen) in Nanjing during the Asian Youth Games (AYG), and organic carbon (OC) and elemental carbon (EC) in particles were determined by DRI Model 2001A carbon analyzer of USA. Observations indicated that OC (51.55%) and EC (54.

[Pollution characteristics of organic and elemental carbon in atmospheric particles in Nanjing northern suburb in summer].

To understand organic carbon (OC) and elemental carbon (EC) mass concentration, the particles samples were collected by an Andersen cascade impactor and analyzed with the DRI analyzer in Nanjing northern suburb during May to July in 2013. The results showed that the average mass concentrations of EC and OC in PM2.1 were (2.

[Variation characteristics of ambient volatile organic compounds (VOCs) in Nanjing northern suburb, China].

Based on the data of volatile organic compounds (VOCs) collected continuously from Mar 1, 2011 to Feb 29, 2012 in the northern suburb of Nanjing, characteristics of their temporal variation, photochemical reactivity of their compositions and source characteristics of VOCs were analyzed. The results showed that the mean value of VOCs mixing ratios was 43.52 x 10(-9) (volume fraction).

[Characteristics of VOCs and their photochemical reactivity in autumn in Nanjing northern suburb].

A continuous observation campaign was carried out with the GC5000 volatile organics online monitoring system and the EMS system for one month in November 2011 in the northern suburb of Nanjing, and 56 VOC components and reactive gases (NO(x), CO and O3) were measured. The results showed that the VOC hourly averaged volume fraction in Nanjing northern suburb was about 48.17 x 10(-9), and the minimum value of VOCs occurred at 16:00.

[Observation and analysis of air pollution in Zhangjiakou, Hebei].

Zhangjiakou is an important city in the north of Hebei province with rapidly developing industry in recent years, which has little precipitation and a very fragile ecological environment. The observation of atmospheric pollutants was done from December 2009 to November 2010 to illuminate the air pollution situation. The results showed that the annual mean concentration of PM10, the primary pollutant, reached (137 +/- 105) microg x m(-3), and those of NO, NO2, SO2 and O3 were (8 +/- 13), (30 +/- 15), (19 +/- 26) and (54 +/- 35) microg x m(-3), respectively; The seasonal mean concentrations of NOx and SO2 were highest in winter, with values of (51 +/- 35) microg x m(-3) and (42 +/- 29) microg x m(-3), respectively, and lowest in summer, only (28 +/- 8) and (4 +/- 3) microg x m(-3), respectively.