Pub Date : 2023-10-01DOI: 10.1016/j.jes.2022.08.029
Naghmeh Bayati, Saeed Dehghanpour
In the present work, functional diamine groups into indium frameworks to synthesize cyclic carbonates from CO2 and epoxides with efficient catalytic activity in the absence of co-catalyst and solvent are reported for the first time. Crystalline porous materials (CPM)-5 modified with 1,2-phenylene diamine and ethylene diamine (CPM-5-PhDA and CPM-5-EDA), were prepared using a post-synthetic modification (PSM) method. The properties of the modified CPM-5 were characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), N2-adsorption, scanning electron microscopy (SEM), CO2 adsorption, and temperature programmed desorption TPD methods. The presence of diamine groups as basic sites and indium Lewis acid sites in the framework structure were desirable for high catalytic activity. For a given catalyst weight, CPM-5-PhDA was the best candidate to appear with great catalytic activity and selectivity for the cycloaddition reaction at 100°C and 1 MPa CO2 under co-catalyst and solvent free conditions. CPM-5-PhDA also was found to afford large and bulky epoxides. The catalyst can be easily separated and reused five times without any decline in activity.
{"title":"Diamine-modified porous indium frameworks with crystalline porous materials (CPM)-5 structure for carbon dioxide fixation under co-catalyst and solvent free conditions","authors":"Naghmeh Bayati, Saeed Dehghanpour","doi":"10.1016/j.jes.2022.08.029","DOIUrl":"10.1016/j.jes.2022.08.029","url":null,"abstract":"<div><p>In the present work, functional diamine groups into indium frameworks to synthesize cyclic carbonates from CO<sub>2</sub> and epoxides with efficient catalytic activity in the absence of co-catalyst and solvent are reported for the first time. Crystalline porous materials (CPM)-5 modified with 1,2-phenylene diamine and ethylene diamine (CPM-5-PhDA and CPM-5-EDA), were prepared using a post-synthetic modification (PSM) method. The properties of the modified CPM-5 were characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), N<sub>2</sub>-adsorption, scanning electron microscopy (SEM), CO<sub>2</sub> adsorption, and temperature programmed desorption TPD methods. The presence of diamine groups as basic sites and indium Lewis acid sites in the framework structure were desirable for high catalytic activity. For a given catalyst weight, CPM-5-PhDA was the best candidate to appear with great catalytic activity and selectivity for the cycloaddition reaction at 100°C and 1 MPa CO<sub>2</sub> under co-catalyst and solvent free conditions. CPM-5-PhDA also was found to afford large and bulky epoxides. The catalyst can be easily separated and reused five times without any decline in activity.</p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 12-21"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9660414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.1016/j.jes.2022.09.032
Xi Mu , Sichen Wang , Peng Jiang , Yanlan Wu
Recently, the global background concentration of ozone (O3) has demonstrated a rising trend. Among various methods, groun-based monitoring of O3 concentrations is highly reliable for research analysis. To obtain information on the spatial characteristics of O3 concentrations, it is necessary that the ground monitoring sites be constructed in sufficient density. In recent years, many researchers have used machine learning models to estimate surface O3 concentrations, which cannot fully provide the spatial and temporal information contained in a sample dataset. To solve this problem, the current study utilized a deep learning model called the Residual connection Convolutional Long Short-Term Memory network (R-ConvLSTM) to estimate daily maximum 8-hr average (MDA8) O3 over Jiangsu province, China during 2020. In this research, the R-ConvLSTM model not only provides the spatiotemporal information of MDA8 O3, but also involves residual connection to avoid the problem of gradient explosion and gradient disappearance with the deepening of network layers. We utilized the TROPOMI total O3 column retrieved from Sentinel-5 Precursor, ERA5 reanalysis meteorological data, and other supplementary data to build a pre-trained dataset. The R-ConvLSTM model achieved an overall sample-base cross-validation (CV) R2 of 0.955 with root mean square error (RMSE) of 9.372 µg/m3. Model estimation also showed a city-based CV R2 of 0.896 with RMSE of 14.029 µg/m3, the highest MDA8 O3 in spring being 122.60 ± 31.60 µg/m3 and the lowest in winter being 69.93 ± 18.48 µg/m3.
{"title":"Estimation of surface ozone concentration over Jiangsu province using a high-performance deep learning model","authors":"Xi Mu , Sichen Wang , Peng Jiang , Yanlan Wu","doi":"10.1016/j.jes.2022.09.032","DOIUrl":"10.1016/j.jes.2022.09.032","url":null,"abstract":"<div><p>Recently, the global background concentration of ozone (O<sub>3</sub>) has demonstrated a rising trend. Among various methods, groun-based monitoring of O<sub>3</sub> concentrations is highly reliable for research analysis. To obtain information on the spatial characteristics of O<sub>3</sub> concentrations, it is necessary that the ground monitoring sites be constructed in sufficient density. In recent years, many researchers have used machine learning models to estimate surface O<sub>3</sub> concentrations, which cannot fully provide the spatial and temporal information contained in a sample dataset. To solve this problem, the current study utilized a deep learning model called the Residual connection Convolutional Long Short-Term Memory network (R-ConvLSTM) to estimate daily maximum 8-hr average (MDA8) O<sub>3</sub> over Jiangsu province, China during 2020. In this research, the R-ConvLSTM model not only provides the spatiotemporal information of MDA8 O<sub>3</sub>, but also involves residual connection to avoid the problem of gradient explosion and gradient disappearance with the deepening of network layers. We utilized the TROPOMI total O<sub>3</sub> column retrieved from Sentinel-5 Precursor, ERA5 reanalysis meteorological data, and other supplementary data to build a pre-trained dataset. The R-ConvLSTM model achieved an overall sample-base cross-validation (CV) <em>R</em><sup>2</sup><span> of 0.955 with root mean square error (RMSE) of 9.372 µg/m</span><sup>3</sup>. Model estimation also showed a city-based CV <em>R</em><sup>2</sup> of 0.896 with RMSE of 14.029 µg/m<sup>3</sup>, the highest MDA8 O<sub>3</sub> in spring being 122.60 ± 31.60 µg/m<sup>3</sup> and the lowest in winter being 69.93 ± 18.48 µg/m<sup>3</sup>.</p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 122-133"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9660415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.1016/j.jes.2022.07.039
Shandong Lei , Baozhu Ge , Hang Liu , Jiannong Quan , Danhui Xu , Yuting Zhang , Weijie Yao , Lu Lei , Yu Tian , Qi Liao , Xiaoyong Liu , Jie Li , Jinyuan Xin , Yele Sun , Pingqing Fu , Junji Cao , Zifa Wang , Xiaole Pan
Black carbon (BC) aerosols in the atmosphere play a significant role in climate systems due to their strong ability to absorb solar radiation. The lifetime of BC depends on atmospheric transport, aging and consequently on wet scavenging processes (in-cloud and below-cloud scavenging). In this study, sequential rainwater samples in eight rainfall events collected in 2 mm interval were measured by a tandem system including a single particle soot photometer (SP2) and a nebulizer. The results showed that the volume-weighted average (VWA) mass concentrations of refractory black carbon (rBC) in each rainfall event varied, ranging from 10.8 to 78.9 µg/L. The highest rBC concentrations in the rainwater samples typically occurred in the first fraction from individual rainfall events. The geometric mean median mass-equivalent diameter (MMD) decreased under precipitation, indicating that rBC with larger sizes was relatively aged and preferentially removed by wet scavenging. A positive correlation (R2 = 0.73) between the VWA mass concentrations of rBC in rainwater and that in ambient air suggested the important contribution of scavenging process. Additionally, the contributions of in-cloud and below-cloud scavenging were distinguished and accounted for 74% and 26% to wet scavenging, respectively. The scavenging ratio of rBC particles was estimated to be 0.06 on average. This study provides helpful information for better understanding the mechanism of rBC wet scavenging and reducing the uncertainty of numerical simulations of the climate effects of rBC.
{"title":"Refractory black carbon aerosols in rainwater in the summer of 2019 in Beijing: Mass concentration, size distribution and wet scavenging ratio","authors":"Shandong Lei , Baozhu Ge , Hang Liu , Jiannong Quan , Danhui Xu , Yuting Zhang , Weijie Yao , Lu Lei , Yu Tian , Qi Liao , Xiaoyong Liu , Jie Li , Jinyuan Xin , Yele Sun , Pingqing Fu , Junji Cao , Zifa Wang , Xiaole Pan","doi":"10.1016/j.jes.2022.07.039","DOIUrl":"10.1016/j.jes.2022.07.039","url":null,"abstract":"<div><p><span>Black carbon (BC) aerosols in the atmosphere play a significant role in climate systems due to their strong ability to absorb solar radiation. The lifetime of BC depends on atmospheric transport, aging and consequently on wet scavenging processes (in-cloud and below-cloud scavenging). In this study, sequential rainwater samples in eight rainfall events collected in 2 mm interval were measured by a tandem system including a single particle soot photometer (SP2) and a nebulizer. The results showed that the volume-weighted average (VWA) mass concentrations of refractory black carbon (rBC) in each rainfall event varied, ranging from 10.8 to 78.9 µg/L. The highest rBC concentrations in the rainwater samples typically occurred in the first fraction from individual rainfall events. The geometric mean median mass-equivalent diameter (MMD) decreased under precipitation, indicating that </span><em>r</em>BC with larger sizes was relatively aged and preferentially removed by wet scavenging. A positive correlation (<em>R</em><sup>2</sup> = 0.73) between the VWA mass concentrations of <em>r</em>BC in rainwater and that in ambient air suggested the important contribution of scavenging process. Additionally, the contributions of in-cloud and below-cloud scavenging were distinguished and accounted for 74% and 26% to wet scavenging, respectively. The scavenging ratio of rBC particles was estimated to be 0.06 on average. This study provides helpful information for better understanding the mechanism of rBC wet scavenging and reducing the uncertainty of numerical simulations of the climate effects of rBC.</p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 31-42"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9668674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.1016/j.jes.2022.09.034
Shaobin Zhang , Guo Li , Nan Ma , Yao He , Shaowen Zhu , Xihao Pan , Wenlin Dong , Yanyan Zhang , Qingwei Luo , Jeannine Ditas , Uwe Kuhn , Yuxuan Zhang , Bin Yuan , Zelong Wang , Peng Cheng , Juan Hong , Jiangchuan Tao , Wanyun Xu , Ye Kuang , Qiaoqiao Wang , Hang Su
Daytime HONO photolysis is an important source of atmospheric hydroxyl radicals (OH). Knowledge of HONO formation chemistry under typical haze conditions, however, is still limited. In the Multiphase chemistry experiment in Fogs and Aerosols in the North China Plain in 2018, we investigated the wintertime HONO formation and its atmospheric implications at a rural site Gucheng. Three different episodes based on atmospheric aerosol loading levels were classified: clean periods (CPs), moderately polluted periods (MPPs) and severely polluted periods (SPPs). Correlation analysis revealed that HONO formation via heterogeneous conversion of was more efficient on aerosol surfaces than on ground, highlighting the important role of aerosols in promoting HONO formation. Daytime HONO budget analysis indicated a large missing source (with an average production rate of 0.66 ± 0.26, 0.97 ± 0.47 and 1.45 ± 0.55 ppbV/hr for CPs, MPPs and SPPs, respectively), which strongly correlated with photo-enhanced reactions ( heterogeneous reaction and particulate nitrate photolysis). Average OH formation derived from HONO photolysis reached up to (0.92 ± 0.71), (1.75 ± 1.26) and (1.82 ± 1.47) ppbV/hr in CPs, MPPs and SPPs respectively, much higher than that from photolysis (i.e., (0.004 ± 0.004), (0.006 ± 0.007) and (0.0035 ± 0.0034) ppbV/hr). Such high OH production rates could markedly regulate the atmospheric oxidation capacity and hence promote the formation of secondary aerosols and pollutants.
{"title":"Exploring HONO formation and its role in driving secondary pollutants formation during winter in the North China Plain","authors":"Shaobin Zhang , Guo Li , Nan Ma , Yao He , Shaowen Zhu , Xihao Pan , Wenlin Dong , Yanyan Zhang , Qingwei Luo , Jeannine Ditas , Uwe Kuhn , Yuxuan Zhang , Bin Yuan , Zelong Wang , Peng Cheng , Juan Hong , Jiangchuan Tao , Wanyun Xu , Ye Kuang , Qiaoqiao Wang , Hang Su","doi":"10.1016/j.jes.2022.09.034","DOIUrl":"10.1016/j.jes.2022.09.034","url":null,"abstract":"<div><p><span>Daytime HONO photolysis is an important source of atmospheric hydroxyl radicals (OH). Knowledge of HONO formation chemistry under typical haze conditions, however, is still limited. In the Multiphase chemistry experiment in Fogs and Aerosols in the North China Plain in 2018, we investigated the wintertime HONO formation and its atmospheric implications at a rural site Gucheng. Three different episodes based on atmospheric aerosol loading levels were classified: clean periods (CPs), moderately polluted periods (MPPs) and severely polluted periods (SPPs). Correlation analysis revealed that HONO formation via heterogeneous conversion of </span><span><math><mrow><mi>N</mi><msub><mi>O</mi><mn>2</mn></msub></mrow></math></span> was more efficient on aerosol surfaces than on ground, highlighting the important role of aerosols in promoting HONO formation. Daytime HONO budget analysis indicated a large missing source (with an average production rate of 0.66 ± 0.26, 0.97 ± 0.47 and 1.45 ± 0.55 ppbV/hr for CPs, MPPs and SPPs, respectively), which strongly correlated with photo-enhanced reactions (<span><math><mrow><mi>N</mi><msub><mi>O</mi><mn>2</mn></msub></mrow></math></span> heterogeneous reaction and particulate nitrate photolysis). Average OH formation derived from HONO photolysis reached up to (0.92 ± 0.71), (1.75 ± 1.26) and (1.82 ± 1.47) ppbV/hr in CPs, MPPs and SPPs respectively, much higher than that from <span><math><msub><mi>O</mi><mn>3</mn></msub></math></span> photolysis (i.e., (0.004 ± 0.004), (0.006 ± 0.007) and (0.0035 ± 0.0034) ppbV/hr). Such high OH production rates could markedly regulate the atmospheric oxidation capacity and hence promote the formation of secondary aerosols and pollutants.</p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 83-97"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9668669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.1016/j.jes.2022.08.030
Hairong Zhang , Ang Li , Zhaokun Hu , Hongmei Ren , Hongyan Zhong , Jianfeng Guo , Long Yun , Mingdi Zhang
Long-term stereoscopic observations of aerosol, NO2, and HCHO were carried out at the Yangmeikeng (YMK) site in Shenzhen. Aerosol optical depths and NO2 vertical column concentration (NO2 VCD) derived from MAX-DOAS were found to be consistent with other datasets. The total NO2 VCD values of the site remained low, varying from 2 × 1015 to 8 × 1015 mol/cm2, while the HCHO VCD was higher than NO2 VCD, varying from 7 × 1015 to 11 × 1015 mol/cm2. HCHO VCD was higher from September to early November than that was from mid-late November to December and during February 2021, in contrast, NO2 VCD did not change much during the same period. In January, NO2 VCD and HCHO VCD were both fluctuating drastically. High temperature and HCHO level in the YMK site is not only driving the ozone production up but also may be driving up the ozone concentration as well, and the O3 production regime in the YMK site tends to be NOx-limited. At various altitudes, backward trajectory clustering analysis and Potential Source Contribution Function (PSCF) were utilized to identify possible NO2 and HCHO source locations. The results suggested that the Huizhou-Shanwei border and the Daya Bay Sea area were the key potential source locations in the lower (200 m) and middle (500 m) atmosphere (WPSCF > 0.6). The WPSCF value was high at the 1000 m altitude which was closer to the YMK site than the near ground, indicating that the pollution transport capability in the upper atmosphere was limited.
{"title":"Observation on the aerosol and ozone precursors in suburban areas of Shenzhen and analysis of potential source based on MAX-DOAS","authors":"Hairong Zhang , Ang Li , Zhaokun Hu , Hongmei Ren , Hongyan Zhong , Jianfeng Guo , Long Yun , Mingdi Zhang","doi":"10.1016/j.jes.2022.08.030","DOIUrl":"10.1016/j.jes.2022.08.030","url":null,"abstract":"<div><p>Long-term stereoscopic observations of aerosol, NO<sub>2</sub>, and HCHO were carried out at the Yangmeikeng (YMK) site in Shenzhen. Aerosol optical depths and NO<sub>2</sub> vertical column concentration (NO<sub>2</sub> VCD) derived from MAX-DOAS were found to be consistent with other datasets. The total NO<sub>2</sub> VCD values of the site remained low, varying from 2 × 10<sup>15</sup> to 8 × 10<sup>15</sup> mol/cm<sup>2</sup>, while the HCHO VCD was higher than NO<sub>2</sub> VCD, varying from 7 × 10<sup>15</sup> to 11 × 10<sup>15</sup> mol/cm<sup>2</sup>. HCHO VCD was higher from September to early November than that was from mid-late November to December and during February 2021, in contrast, NO<sub>2</sub> VCD did not change much during the same period. In January, NO<sub>2</sub> VCD and HCHO VCD were both fluctuating drastically. High temperature and HCHO level in the YMK site is not only driving the ozone production up but also may be driving up the ozone concentration as well, and the O<sub>3</sub> production regime in the YMK site tends to be NO<sub>x</sub>-limited. At various altitudes, backward trajectory clustering analysis and Potential Source Contribution Function (PSCF) were utilized to identify possible NO<sub>2</sub> and HCHO source locations. The results suggested that the Huizhou-Shanwei border and the Daya Bay Sea area were the key potential source locations in the lower (200 m) and middle (500 m) atmosphere (WPSCF > 0.6). The WPSCF value was high at the 1000 m altitude which was closer to the YMK site than the near ground, indicating that the pollution transport capability in the upper atmosphere was limited.</p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 109-121"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9668671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Non-thermal plasma (NTP) has been demonstrated as one of the promising technologies that can degrade volatile organic compounds (VOCs) under ambient condition. However, one of the key challenges of VOCs degradation in NTP is its relatively low mineralization rate, which needs to be addressed by introducing catalysts. Therefore, the design and optimization of catalysts have become the focus of NTP coupling catalysis research. In this work, a series of two-dimensional nanosheet Co-Ni metal oxides were synthesized by microwave method and investigated for the catalytic oxidation of benzene in an NTP-catalysis coupling system. Among them, Co2Ni1Ox achieves 60% carbon dioxide (CO2) selectivity (SCO2) when the benzene removal efficiency (REbenzene) reaches more than 99%, which is a significant enhancement compared with the CO2 selectivity obtained without any catalysts (38%) under the same input power. More intriguingly, this SCO2 is also significantly higher than that of single metal oxides, NiO or Co3O4, which is only around 40%. Such improved performance of this binary metal oxide catalyst is uniquely attributed to the synergistic effects of Co and Ni in Co2Ni1Ox catalyst. The introduction of Co2Ni1Ox was found to promote the generation of acrolein significantly, one of the key intermediates found in NTP alone system reported previously, suggest the benzene ring open reaction is promoted. Compared with monometallic oxides NiO and Co3O4, Co2Ni1Ox also shows higher active oxygen proportion, better oxygen mobility, and stronger low-temperature redox capability. The above factors result in the improved catalytic performance of Co2Ni1Ox in the NTP coupling removal of benzene.
{"title":"Catalytic degradation of benzene over non-thermal plasma coupled Co-Ni binary metal oxide nanosheet catalysts","authors":"Zhi Jiang , Dongxu Fang , Yuting Liang , Yaoyu He , Hisahiro Einaga , Wenfeng Shangguan","doi":"10.1016/j.jes.2022.09.030","DOIUrl":"10.1016/j.jes.2022.09.030","url":null,"abstract":"<div><p><span><span>Non-thermal plasma (NTP) has been demonstrated as one of the promising technologies that can degrade volatile organic compounds (VOCs) under ambient condition. However, one of the key challenges of VOCs degradation in NTP is its relatively low mineralization rate, which needs to be addressed by introducing catalysts. Therefore, the design and optimization of catalysts have become the focus of NTP coupling catalysis research. In this work, a series of two-dimensional nanosheet Co-Ni </span>metal oxides were synthesized by microwave method and investigated for the catalytic oxidation of benzene in an NTP-catalysis coupling system. Among them, Co</span><sub>2</sub>Ni<sub>1</sub>O<em><sub>x</sub></em> achieves 60% carbon dioxide (CO<sub>2</sub><span>) selectivity (</span><em>S</em><sub>CO2</sub>) when the benzene removal efficiency (RE<sub>benzene</sub>) reaches more than 99%, which is a significant enhancement compared with the CO<sub>2</sub> selectivity obtained without any catalysts (38%) under the same input power. More intriguingly, this <em>S</em><sub>CO2</sub> is also significantly higher than that of single metal oxides, NiO or Co<sub>3</sub>O<sub>4</sub>, which is only around 40%. Such improved performance of this binary metal oxide catalyst is uniquely attributed to the synergistic effects of Co and Ni in Co<sub>2</sub>Ni<sub>1</sub>O<sub>x</sub> catalyst. The introduction of Co<sub>2</sub>Ni<sub>1</sub>O<em><sub>x</sub></em><span> was found to promote the generation of acrolein significantly, one of the key intermediates found in NTP alone system reported previously, suggest the benzene ring open reaction is promoted. Compared with monometallic oxides NiO and Co</span><sub>3</sub>O<sub>4</sub>, Co<sub>2</sub>Ni<sub>1</sub>O<em><sub>x</sub></em> also shows higher active oxygen proportion, better oxygen mobility, and stronger low-temperature redox capability. The above factors result in the improved catalytic performance of Co<sub>2</sub>Ni<sub>1</sub>O<em><sub>x</sub></em> in the NTP coupling removal of benzene.</p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 1-11"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9668667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.1016/j.jes.2022.07.031
Chang Hoon Jung , Hyung-Min Lee , Dasom Park , Young Jun Yoon , Yongjoo Choi , Junshik Um , Seoung Soo Lee , Ji Yi Lee , Yong Pyo Kim
The below-cloud aerosol scavenging process by precipitation is one of the most important mechanisms to remove aerosols from the atmosphere. Due to its complexity and dependence on both aerosol and raindrop sizes, wet scavenging process has been poorly treated, especially during the removal of fine particles. This makes the numerical simulation of below-cloud scavenging in large-scale aerosol models unrealistic. To consider the slip effects of submicron particles, a simplified expression for the diffusion scavenging was developed by approximating the Cunningham slip correction factor. The derived analytic solution was parameterized as a simple power function of rain intensity under the assumption of the lognormal size distribution of particles. The resultant approximated expression was compared to the observed data and the results of previous studies including a 3D atmospheric chemical transport model simulation. Compared with the default GEOS-Chem coefficient of 0.00106R0.61 and the observation-based coefficient of 0.0144R0.9268, the coefficient of a and b in Λm = aRb spread in the range of 0.0002- 0.1959 for a and 0.3261- 0.525 for b over a size distribution of GSD of 1.3–2.5 and a geometric mean diameter of 0.01- 2.5 µm. Overall, this study showed that the scavenging coefficient varies widely by orders of magnitude according to the size distribution of particles and rain intensity. This study also demonstrated that the obtained simplified expression could consider the theoretical approach of aerosol polydispersity. Our proposed analytic approach showed that results can be effectively applied for reduced computational burden in atmospheric modeling.
{"title":"Parameterization of below-cloud scavenging for polydisperse fine mode aerosols as a function of rain intensity","authors":"Chang Hoon Jung , Hyung-Min Lee , Dasom Park , Young Jun Yoon , Yongjoo Choi , Junshik Um , Seoung Soo Lee , Ji Yi Lee , Yong Pyo Kim","doi":"10.1016/j.jes.2022.07.031","DOIUrl":"10.1016/j.jes.2022.07.031","url":null,"abstract":"<div><p>The below-cloud aerosol scavenging process by precipitation is one of the most important mechanisms to remove aerosols from the atmosphere. Due to its complexity and dependence on both aerosol and raindrop sizes, wet scavenging process has been poorly treated, especially during the removal of fine particles. This makes the numerical simulation of below-cloud scavenging in large-scale aerosol models unrealistic. To consider the slip effects of submicron particles, a simplified expression for the diffusion scavenging was developed by approximating the Cunningham slip correction factor. The derived analytic solution was parameterized as a simple power function of rain intensity under the assumption of the lognormal size distribution of particles. The resultant approximated expression was compared to the observed data and the results of previous studies including a 3D atmospheric chemical transport model simulation. Compared with the default GEOS-Chem coefficient of 0.00106<em>R</em><sup>0.61</sup> and the observation-based coefficient of 0.0144<em>R</em><sup>0.9268</sup>, the coefficient of <em>a</em> and <em>b</em> in <em>Λ<sub>m</sub> = aR<sup>b</sup></em> spread in the range of 0.0002- 0.1959 for a and 0.3261- 0.525 for <em>b</em> over a size distribution of GSD of 1.3–2.5 and a geometric mean diameter of 0.01- 2.5 µm. Overall, this study showed that the scavenging coefficient varies widely by orders of magnitude according to the size distribution of particles and rain intensity. This study also demonstrated that the obtained simplified expression could consider the theoretical approach of aerosol polydispersity. Our proposed analytic approach showed that results can be effectively applied for reduced computational burden in atmospheric modeling.</p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 43-55"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9668673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.1016/j.jes.2022.07.034
Wenlu Wang , Yang Xiao , Shijie Han , Yang Zhang , Daocheng Gong , Hao Wang , Boguang Wang
Smog chambers are the effective tools for studying formation mechanisms of air pollution. Simulations by traditional smog chambers differ to a large extent from real atmospheric conditions, including light, temperature and atmospheric composition. However, the existing parameters for mechanism interpretation are derived from the traditional smog chambers. To address the gap between the traditional laboratory simulations and the photochemistry in the real atmosphere, a vehicle-mounted indoor-outdoor dual-smog chamber (JNU-VMDSC) was developed, which can be quickly transferred to the desired sites to simulate quasi-realistic atmosphere simultaneously in both chambers using “local air”. Multiple key parameters of the smog chamber were characterized in the study, demonstrating that JNU-VMDSC meets the requirements of general atmospheric chemistry simulation studies. Additionally, the preliminary results for the photochemical simulations of quasi-realistic atmospheres in Pearl River Delta region and Nanling Mountains are consistent with literature reports on the photochemistry in this region. JNU-VMDSC provides a convenient and reliable experimental device and means to study the mechanism of atmospheric photochemical reactions to obtain near-real results, and will make a great contribution to the control of composite air pollution.
{"title":"A vehicle-mounted dual-smog chamber: Characterization and its preliminary application to evolutionary simulation of photochemical processes in a quasi-realistic atmosphere","authors":"Wenlu Wang , Yang Xiao , Shijie Han , Yang Zhang , Daocheng Gong , Hao Wang , Boguang Wang","doi":"10.1016/j.jes.2022.07.034","DOIUrl":"10.1016/j.jes.2022.07.034","url":null,"abstract":"<div><p>Smog chambers are the effective tools for studying formation mechanisms of air pollution. Simulations by traditional smog chambers differ to a large extent from real atmospheric conditions, including light, temperature and atmospheric composition<span>. However, the existing parameters for mechanism interpretation are derived from the traditional smog chambers. To address the gap between the traditional laboratory simulations and the photochemistry<span> in the real atmosphere, a vehicle-mounted indoor-outdoor dual-smog chamber (JNU-VMDSC) was developed, which can be quickly transferred to the desired sites to simulate quasi-realistic atmosphere simultaneously in both chambers using “local air”. Multiple key parameters of the smog chamber were characterized in the study, demonstrating that JNU-VMDSC meets the requirements of general atmospheric chemistry simulation studies. Additionally, the preliminary results for the photochemical simulations of quasi-realistic atmospheres in Pearl River Delta region and Nanling Mountains are consistent with literature reports on the photochemistry in this region. JNU-VMDSC provides a convenient and reliable experimental device and means to study the mechanism of atmospheric photochemical reactions to obtain near-real results, and will make a great contribution to the control of composite air pollution.</span></span></p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 98-108"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10042860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.1016/j.jes.2022.07.007
Haibin Wang , Lihui Han , Tingting Li , Song Qu , Yuncheng Zhao , Shoubin Fan , Tong Chen , Haoran Cui , Junfang Liu
Road silt loading (sL) is an important parameter in the fugitive road dust (FRD) emissions. In this study, the improved Testing Re-entrained Aerosol Kinetic Emissions from Roads (TRAKER) combined with the AP-42 method was firstly developed to quickly measure and estimate the sLs of paved roads in Beijing, China. The annual average sLs in Beijing was 0.59±0.31 g/m2 in 2020, and decreased by 22.4% compared with that in 2019. The seasonal variations of sLs followed the order of spring > winter > summer > autumn in the two years. The seasonal mean road sLs on the same type road in the four seasons presented a decline trend from 2019 to 2020, especially on the Express way, decreasing 47.4%-72.7%. The road sLs on the different type roads in the same season followed the order of Major arterial ∼ Minor arterial ∼ Branch road > Express road, and Township road ∼ Country highway > Provincial highway ∼ National highway. The emission intensities of PM10 and PM2.5 from FRD in Beijing in 2020 were lower than those in 2019. The PM10 and PM2.5 emission intensities at the four planning areas in the two years all presented the order of the capital functional core area > the urban functional expansion area > the urban development new area > the ecological conservation and development area. The annual emissions of PM10 and PM2.5 from FRD in Beijing in 2020 were 74,886 ton and 18,118 ton, respectively, decreasing by ∼33.3% compared with those in 2019.
{"title":"Temporal-spatial distributions of road silt loadings and fugitive road dust emissions in Beijing from 2019 to 2020","authors":"Haibin Wang , Lihui Han , Tingting Li , Song Qu , Yuncheng Zhao , Shoubin Fan , Tong Chen , Haoran Cui , Junfang Liu","doi":"10.1016/j.jes.2022.07.007","DOIUrl":"10.1016/j.jes.2022.07.007","url":null,"abstract":"<div><p>Road silt loading (sL) is an important parameter in the fugitive road dust (FRD) emissions. In this study, the improved Testing Re-entrained Aerosol Kinetic Emissions from Roads (TRAKER) combined with the AP-42 method was firstly developed to quickly measure and estimate the sLs of paved roads in Beijing, China. The annual average sLs in Beijing was 0.59±0.31 g/m<sup>2</sup> in 2020, and decreased by 22.4% compared with that in 2019. The seasonal variations of sLs followed the order of spring > winter > summer > autumn in the two years. The seasonal mean road sLs on the same type road in the four seasons presented a decline trend from 2019 to 2020, especially on the Express way, decreasing 47.4%-72.7%. The road sLs on the different type roads in the same season followed the order of Major arterial ∼ Minor arterial ∼ Branch road > Express road, and Township road ∼ Country highway > Provincial highway ∼ National highway. The emission intensities of PM<sub>10</sub> and PM<sub>2.5</sub> from FRD in Beijing in 2020 were lower than those in 2019. The PM<sub>10</sub> and PM<sub>2.5</sub> emission intensities at the four planning areas in the two years all presented the order of the capital functional core area > the urban functional expansion area > the urban development new area > the ecological conservation and development area. The annual emissions of PM<sub>10</sub> and PM<sub>2.5</sub> from FRD in Beijing in 2020 were 74,886 ton and 18,118 ton, respectively, decreasing by ∼33.3% compared with those in 2019.</p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 56-70"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10042858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01DOI: 10.1016/j.jes.2022.07.017
Shengwei Yi , Feng Li , Chen Wu , Fei Ge , Chuang Feng , Ming Zhang , Yun Liu , Hainan Lu
This study investigated the transformations of heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) in rhizosphere soils and adaptive responses of rhizobacterial community under the real field conditions during four growth stages (e.g., greening, tillering, heading, and maturity) of early rice (Zhongjiazao 17) and late rice (Zhongyou 9918) in Jiangshe village (JSV) and Yangji village (YJV). Results showed that rhizosphere soils of YJV were mildly polluted by Cd and PAHs compared to that of JSV. The relative abundance of bioavailable Cd (bio-Cd) and bioavailable As (bio-As) in rhizosphere soil increased before the heading stage but decreased at the subsequent growth stage, but the content of ΣPAHs in rhizosphere soil decreased gradually during whole growth period. The dominant rhizobacteria genera at YJV (e.g., Bacillus, Massilia, Sphingomonas, and Geobacter) increased at an abundance level from the tillering to heading stage. Rhizobacteria interacted with the above co-pollutant more intensely at the tillering and heading stage, where genes involved in HM-resistance and PAH-degradation appeared to have a significant enhancement. The contents of bio-Cd and bio-As in rhizosphere soil of early rice were higher than that of late rice at each growth stage, especially at the heading stage. Bio-Cd, ΣPAHs, and organic matter were key factors influencing the community structure of rhizobacteria. Results of this study provide valuable insights about the interactions between HM-PAH co-pollutant and rhizobacterial community under real field conditions and thus develop in-situ rhizosphere remediation techniques for contaminated paddy fields.
{"title":"Co-transformation of HMs-PAHs in rhizosphere soils and adaptive responses of rhizobacteria during whole growth period of rice (Oryza sativa L.)","authors":"Shengwei Yi , Feng Li , Chen Wu , Fei Ge , Chuang Feng , Ming Zhang , Yun Liu , Hainan Lu","doi":"10.1016/j.jes.2022.07.017","DOIUrl":"10.1016/j.jes.2022.07.017","url":null,"abstract":"<div><p>This study investigated the transformations of heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) in rhizosphere soils and adaptive responses of rhizobacterial community under the real field conditions during four growth stages (e.g., greening, tillering, heading, and maturity) of early rice (Zhongjiazao 17) and late rice (Zhongyou 9918) in Jiangshe village (JSV) and Yangji village (YJV). Results showed that rhizosphere soils of YJV were mildly polluted by Cd and PAHs compared to that of JSV. The relative abundance of bioavailable Cd (bio-Cd) and bioavailable As (bio-As) in rhizosphere soil increased before the heading stage but decreased at the subsequent growth stage, but the content of ΣPAHs in rhizosphere soil decreased gradually during whole growth period. The dominant rhizobacteria genera at YJV (e.g., <em>Bacillus, Massilia, Sphingomonas</em>, and <em>Geobacter</em>) increased at an abundance level from the tillering to heading stage. Rhizobacteria interacted with the above co-pollutant more intensely at the tillering and heading stage, where genes involved in HM-resistance and PAH-degradation appeared to have a significant enhancement. The contents of bio-Cd and bio-As in rhizosphere soil of early rice were higher than that of late rice at each growth stage, especially at the heading stage. Bio-Cd, ΣPAHs, and organic matter were key factors influencing the community structure of rhizobacteria. Results of this study provide valuable insights about the interactions between HM-PAH co-pollutant and rhizobacterial community under real field conditions and thus develop in-situ rhizosphere remediation techniques for contaminated paddy fields.</p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"132 ","pages":"Pages 71-82"},"PeriodicalIF":6.9,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10042859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}