Journal articles on the topic 'Nitrogen oxides China'
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1
Tong, Zheng Ming, and Shu Jun Liang. "Aluminum Hydrogen Energy Industry in China." Applied Mechanics and Materials 71-78 (July 2011): 2035–38. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.2035.
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The real solution to the emissions of carbon dioxide and nitrogen and sulfur oxides is obvious: China needs to break its addiction to fossil fuels. The perfect alternative fuel will be hydrogen. The reaction of water with aluminum and its alloys can generate hydrogen. This paper introduces the concept of aluminum hydrogen energy industry and discusses the development of aluminum hydrogen energy industry in China.
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Ke, Piaopiao, Qian Yu, Yao Luo, Ronghua Kang, and Lei Duan. "Fluxes of nitrogen oxides above a subtropical forest canopy in China." Science of The Total Environment 715 (May 2020): 136993. http://dx.doi.org/10.1016/j.scitotenv.2020.136993.
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Fengxia, Guo, Bao Min, Mu Yijun, Liu Zupei, Li Yawen, and Shi Haifeng. "Temporal and spatial characteristics of lightning-produced nitrogen oxides in China." Journal of Atmospheric and Solar-Terrestrial Physics 149 (November 2016): 100–107. http://dx.doi.org/10.1016/j.jastp.2016.10.007.
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Lu, Haoxian, Xiaopu Lyu, Hairong Cheng, Zhenhao Ling, and Hai Guo. "Overview on the spatial–temporal characteristics of the ozone formation regime in China." Environmental Science: Processes & Impacts 21, no. 6 (2019): 916–29. http://dx.doi.org/10.1039/c9em00098d.
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Ozone (O3), a main component in photochemical smog, is a secondary pollutant formed through complex photochemical reactions involving nitrogen oxides (NOx) and volatile organic compounds (VOCs).
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Aneja, Viney P., William H. Schlesinger, Qi Li, Alberth Nahas, and William H. Battye. "Atmospheric Nitrogen Oxides Emissions from Global Agricultural Soils: Present and Future." INTERNATIONAL JOURNAL OF PLANT AND ENVIRONMENT 7, no. 01 (April 15, 2021): 1–10. http://dx.doi.org/10.18811/ijpen.v7i01.1.
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Global nitric oxide (NO) emissions to the atmosphere are projected to increase in the coming years with the increased use of synthetic nitrogen fertilizers and fossil fuel combustion. Here, a statistical model (NO_STAT) is developed for characterizing atmospheric NO emissions from agricultural soil sources, and it is compared to the performance of other global and regional NO emissions (e.g., EDGAR and U.S. EPA). The statistical model was developed using a multiple linear regression between NO emission and the physicochemical variables. The model was evaluated for 2012 NO emissions. In comparison to other data sets, the model provides a lower global NO estimate by 59%, (NO_STAT: 0.67 Tg N yr-1; EDGAR: 1.62 Tg N yr-1). We also performed a region-based analysis (U.S., India; and China) using the NO_STAT model. For the U.S., the model produces an estimate that is 47% lower in comparison to EDGAR. Meanwhile, the NO_STAT model estimate for India shows NO emissions 75% lower when compared to other data sets i.e. EDGAR (which is a comprehensive emissions inventory used in global/regional air quality modeling, and therefore, we have refered to it as ‘other data sets’). A lower estimate is also seen for China, where the model estimates NO emissions 82% lower than other data sets. The difference in the global estimates is attributed to the lower estimates in major agricultural countries like China and India. The statistical model captures the spatial distribution of global NO emissions by utilizing a more simplified approach than those used previously. Moreover, the NO_STAT model provides an opportunity to predict future NO emissions in a changing world. We have made a prediction for future (2050) NO emissions from agricultural soils i.e. emissions from agricultural soils may rise to above ~2.3 TgN/yr, based on anticipated future applications of nitrogen to agricultural soils.
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Zhang, F., Y. Chen, C. Tian, J. Li, G. Zhang, and V. Matthias. "Emissions factors for gaseous and particulate pollutants from offshore diesel engine vessels in China." Atmospheric Chemistry and Physics Discussions 15, no. 17 (September 1, 2015): 23507–41. http://dx.doi.org/10.5194/acpd-15-23507-2015.
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Abstract. Shipping emissions have significant influence on atmospheric environment as well as human health, especially in coastal areas and the harbor districts. However, the contribution of shipping emissions on the environment in China still need to be clarified especially based on measurement data, with the large number ownership of vessels and the rapid developments of ports, international trade and shipbuilding industry. Pollutants in the gaseous phase (carbon monoxide, sulfur dioxide, nitrogen oxides, total volatile organic compounds) and particle phase (particulate matter, organic carbon, elemental carbon, sulfates, nitrate, ammonia, metals) in the exhaust from three different diesel engine power offshore vessels in China were measured in this study. Concentrations, fuel-based and power-based emissions factors for various operating modes as well as the impact of engine speed on emissions were determined. Observed concentrations and emissions factors for carbon monoxide, nitrogen oxides, total volatile organic compounds, and particulate matter were higher for the low engine power vessel than for the two higher engine power vessels. Fuel-based average emissions factors for all pollutants except sulfur dioxide in the low engine power engineering vessel were significantly higher than that of the previous studies, while for the two higher engine power vessels, the fuel-based average emissions factors for all pollutants were comparable to the results of the previous studies. The fuel-based average emissions factor for nitrogen oxides for the small engine power vessel was more than twice the International Maritime Organization standard, while those for the other two vessels were below the standard. Emissions factors for all three vessels were significantly different during different operating modes. Organic carbon and elemental carbon were the main components of particulate matter, while water-soluble ions and elements were present in trace amounts. Best-fit engine speeds during actual operation should be based on both emissions factors and economic costs.
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Lin, J. T., Z. Liu, Q. Zhang, H. Liu, J. Mao, and G. Zhuang. "Modeling uncertainties for tropospheric nitrogen dioxide columns affecting satellite-based inverse modeling of nitrogen oxides emissions." Atmospheric Chemistry and Physics 12, no. 24 (December 21, 2012): 12255–75. http://dx.doi.org/10.5194/acp-12-12255-2012.
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Abstract. Errors in chemical transport models (CTMs) interpreting the relation between space-retrieved tropospheric column densities of nitrogen dioxide (NO2) and emissions of nitrogen oxides (NOx) have important consequences on the inverse modeling. They are however difficult to quantify due to lack of adequate in situ measurements, particularly over China and other developing countries. This study proposes an alternate approach for model evaluation over East China, by analyzing the sensitivity of modeled NO2 columns to errors in meteorological and chemical parameters/processes important to the nitrogen abundance. As a demonstration, it evaluates the nested version of GEOS-Chem driven by the GEOS-5 meteorology and the INTEX-B anthropogenic emissions and used with retrievals from the Ozone Monitoring Instrument (OMI) to constrain emissions of NOx. The CTM has been used extensively for such applications. Errors are examined for a comprehensive set of meteorological and chemical parameters using measurements and/or uncertainty analysis based on current knowledge. Results are exploited then for sensitivity simulations perturbing the respective parameters, as the basis of the following post-model linearized and localized first-order modification. It is found that the model meteorology likely contains errors of various magnitudes in cloud optical depth, air temperature, water vapor, boundary layer height and many other parameters. Model errors also exist in gaseous and heterogeneous reactions, aerosol optical properties and emissions of non-nitrogen species affecting the nitrogen chemistry. Modifications accounting for quantified errors in 10 selected parameters increase the NO2 columns in most areas with an average positive impact of 18% in July and 8% in January, the most important factor being modified uptake of the hydroperoxyl radical (HO2) on aerosols. This suggests a possible systematic model bias such that the top-down emissions will be overestimated by the same magnitude if the model is used for emission inversion without corrections. The modifications however cannot eliminate the large model underestimates in cities and other extremely polluted areas (particularly in the north) as compared to satellite retrievals, likely pointing to underestimates of the a priori emission inventory in these places with important implications for understanding of atmospheric chemistry and air quality. Note that these modifications are simplified and should be interpreted with caution for error apportionment.
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Reis, S., R. W. Pinder, M. Zhang, G. Lijie, and M. A. Sutton. "Reactive nitrogen in atmospheric emission inventories." Atmospheric Chemistry and Physics 9, no. 19 (October 15, 2009): 7657–77. http://dx.doi.org/10.5194/acp-9-7657-2009.
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Abstract. Excess reactive Nitrogen (Nr) has become one of the most pressing environmental problems leading to air pollution, acidification and eutrophication of ecosystems, biodiversity impacts, leaching of nitrates into groundwater and global warming. This paper investigates how current inventories cover emissions of Nr to the atmosphere in Europe, the United States of America, and China. The focus is on anthropogenic sources, assessing the state-of-the-art of quantifying emissions of Ammonia (NH3), Nitrogen Oxides (NOx) and Nitrous Oxide (N2O), the different purposes for which inventories are compiled, and to which extent current inventories meet the needs of atmospheric dispersion modelling. The paper concludes with a discussion of uncertainties involved and a brief outlook on emerging trends in the three regions investigated is conducted. Key issues are substantial differences in the overall magnitude, but as well in the relative sectoral contribution of emissions in the inventories that have been assessed. While these can be explained by the use of different methodologies and underlying data (e.g. emission factors or activity rates), they may lead to quite different results when using the emission datasets to model ambient air quality or the deposition with atmospheric dispersion models. Hence, differences and uncertainties in emission inventories are not merely of academic interest, but can have direct policy implications when the development of policy actions is based on these model results. The level of uncertainty of emission estimates varies greatly between substances, regions and emission source sectors. This has implications for the direction of future research needs and indicates how existing gaps between modelled and measured concentration or deposition rates could be most efficiently addressed. The observed current trends in emissions display decreasing NOx emissions and only slight reductions for NH3 in both Europe and the US. However, in China projections indicate a steep increase of both.
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Zhang, Yuanyuan, Junfeng Liu, Yujing Mu, Shuwei Pei, Xiaoxiu Lun, and Fahe Chai. "Emissions of nitrous oxide, nitrogen oxides and ammonia from a maize field in the North China Plain." Atmospheric Environment 45, no. 17 (June 2011): 2956–61. http://dx.doi.org/10.1016/j.atmosenv.2010.10.052.
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Guo, Fengxia, Xiaoyu Ju, Min Bao, Ganyi Lu, Zupei Liu, Yawen Li, and Yijun Mu. "Relationship between lightning activity and tropospheric nitrogen dioxide and the estimation of lightning-produced nitrogen oxides over China." Advances in Atmospheric Sciences 34, no. 2 (January 7, 2017): 235–45. http://dx.doi.org/10.1007/s00376-016-6087-x.
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Yu, Yang, and Tianchang Wang. "New Urbanization, Energy-Intensive Industries Agglomeration and Analysis of Nitrogen Oxides Emissions Reduction Mechanisms." Atmosphere 12, no. 10 (September 24, 2021): 1244. http://dx.doi.org/10.3390/atmos12101244.
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With the deepening of urbanization and industrialization, as well as the exacerbation of energy consumption, China is facing a severe situation in which nitrogen oxide (NOx) emissions reduction is imperative. In this study, it is aimed to put forward countermeasures and suggestions to reduce NOx emissions by analyzing the impact and mechanism of new urbanization, the agglomeration of energy-intensive industries and mutual interactions on China’s NOx emissions. By analyzing the data of 30 provinces in China from 2006 to 2017, this paper adopted the system generalized method of moments (SYS-GMM) and intermediary effect model to introduce four variables, such as: energy efficiency, human capital, industrial structure and energy structure, which were for empirical analysis. From the results, it was shown that: (1) NOx emissions in China have an accumulated effect; (2) new urbanization inhibits NOx emissions, whilst the agglomeration of energy-intensive industries intensifies NOx emissions. New urbanization weakens the negative impact of the agglomeration of energy-intensive industries on NOx emissions reduction and, (3) among the impacts of new urbanization on NOx emissions, the energy efficiency and human capital reflect the intermediary effect mechanism. At the same time, in the impact of the agglomeration of energy-intensive industries on NOx emissions, the industrial structure and energy structure show the mechanisms of the intermediary effect and masking effect, respectively.
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Tian, Hezhong, Kaiyun Liu, Jiming Hao, Yan Wang, Jiajia Gao, Peipei Qiu, and Chuanyong Zhu. "Nitrogen Oxides Emissions from Thermal Power Plants in China: Current Status and Future Predictions." Environmental Science & Technology 47, no. 19 (September 17, 2013): 11350–57. http://dx.doi.org/10.1021/es402202d.
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Reis, S., R. W. Pinder, M. Zhang, G. Lijie, and M. A. Sutton. "Reactive nitrogen in atmospheric emission inventories – a review." Atmospheric Chemistry and Physics Discussions 9, no. 3 (May 20, 2009): 12413–64. http://dx.doi.org/10.5194/acpd-9-12413-2009.
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Abstract. Excess reactive Nitrogen (Nr) has become one of the most pressing environmental problems leading to air pollution, acidification and eutrophication of ecosystems, biodiversity impacts, leaching of nitrates into groundwater and global warming. This paper investigates how current inventories cover emissions of Nr to the atmosphere in Europe, the United States of America, and The People's Republic of China. The focus is on anthropogenic sources, assessing the state-of-the-art of quantifying emissions of Ammonia (NH3), Nitrogen Oxides (NOx) and Nitrous Oxide (N2O), the different purposes for which inventories are compiled, and to which extent current inventories meet the needs of atmospheric dispersion modelling. The paper concludes with a discussion of uncertainties involved and a brief outlook on emerging trends in the three regions investigated is conducted. Key issues are substantial differences in the overall magnitude, but as well in the relative sectoral contribution of emissions in the inventories that have been assessed. While these can be explained by the use of different methodologies and underlying data (e.g. emission factors or activity rates), they may lead to quite different results when using the emission datasets to model ambient air quality or the deposition with atmospheric dispersion models. Hence, differences and uncertainties in emission inventories are not merely of academic interest, but can have direct policy implications when the development of policy actions is based on these model results. The robustness of emission estimates varies greatly between substances, regions and emission source sectors. This has implications for the direction of future research needs and indicates how existing gaps between modelled and measured concentration or deposition rates could be most efficiently addressed. The observed current trends in emissions display decreasing NOx emissions and only slight reductions for NH3 in both Europe and the US. However, in China projections indicate a steep increase of both.
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Wei, Quan Wei, Ling Jun Liu, Zai Feng Tian, and Hai Bo Feng. "The Characteristics Analysis of Atmospheric Environmental Pollution Impact by Setting Off Firecrackers." Advanced Materials Research 955-959 (June 2014): 2476–80. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.2476.
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As one of China's traditional habits, setting off firecrackers during the holiday season has been going on for thousands of years, especially in north China. This paper selects the atmospheric environmental quality real-time data published by China environmental department, including the AQI, PM10 and PM2.5, sulphur dioxide and nitrogen oxides. It shows that all pollutants have a rising trend during the Spring Festival period, especially from 20:00 at lunar 30th to 4:00 at lunar New Year's Day. From the analysis on the cause, setting off firecrackers during the Spring Festival is the direct cause of the decline in air quality.
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Qi, Fengsheng, Zisong Wang, Baokuan Li, Zhu He, Jakov Baleta, and Milan Vujanovic. "Numerical study on characteristics of combustion and pollutant formation in a reheating furnace." Thermal Science 22, no. 5 (2018): 2103–12. http://dx.doi.org/10.2298/tsci180118277q.
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Energy consumption of fuel-fired industrial furnace accounts for about 23% of the national total energy consumption every year in China. Meanwhile, the reduction of combustion-generated pollutants in furnace has become very important due to the stringent environment laws and policy introduced in the recent years. It is therefore a great challenge for the researchers to simultaneously enhance the fuel efficiency of the furnace while controlling the pollution emission. In this study, a transient 3-D mathematical combustion model coupled with heat transfer and pollution formation model of a walking-beam-type reheating furnace has been developed to simulate the essential combustion, and pollution distribution in the furnace. Based on this model, considering nitrogen oxides formation mechanism, sensitivity study has been carried out to investigate the influence of fuel flow rate, air-fuel ratio on the resultant concentration of nitrogen oxides in the flue gas. The results of present study provide valuable information for improving the thermal efficiency and pollutant control of reheating furnace.
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Wang, Y., Q. Q. Zhang, K. He, Q. Zhang, and L. Chai. "Sulfate-nitrate-ammonium aerosols over China: response to 2000–2015 emission changes of sulfur dioxide, nitrogen oxides, and ammonia." Atmospheric Chemistry and Physics 13, no. 5 (March 5, 2013): 2635–52. http://dx.doi.org/10.5194/acp-13-2635-2013.
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Abstract. We use a chemical transport model to examine the change of sulfate-nitrate-ammonium (SNA) aerosols over China due to anthropogenic emission changes of their precursors (SO2, NOx and NH3) from 2000 to 2015. From 2000 to 2006, annual mean SNA concentrations increased by about 60% over China as a result of the 60% and 80% increases in SO2 and NOx emissions. During this period, sulfate is the dominant component of SNA over South China (SC) and Sichuan Basin (SCB), while nitrate and sulfate contribute equally over North China (NC). Based on emission reduction targets in the 12th (2011–2015) Five-Year Plan (FYP), China's total SO2 and NOx emissions are projected to change by −16% and +16% from 2006 to 2015, respectively. The amount of NH3 emissions in 2015 is uncertain, given the lack of sufficient information on the past and present levels of NH3 emissions in China. With no change in NH3 emissions, SNA mass concentrations in 2015 will decrease over SCB and SC compared to their 2006 levels, but increase over NC where the magnitude of nitrate increase exceeds that of sulfate reduction. This suggests that the SO2 emission reduction target set by the 12th FYP, although effective in reducing SNA over SC and SCB, will not be successful over NC, for which NOx emission control needs to be strengthened. If NH3 emissions are allowed to keep their recent growth rate and increase by +16% from 2006 to 2015, the benefit of SO2 reduction will be completely offset over all of China due to the significant increase of nitrate, demonstrating the critical role of NH3 in regulating nitrate. The effective strategy to control SNA and hence PM2.5 pollution over China should thus be based on improving understanding of current NH3 emissions and putting more emphasis on controlling NH3 emissions in the future.
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Jiang, Jianhui, Jianying Zhang, Yangwei Zhang, Chunlong Zhang, and Guangming Tian. "Estimating nitrogen oxides emissions at city scale in China with a nightlight remote sensing model." Science of The Total Environment 544 (February 2016): 1119–27. http://dx.doi.org/10.1016/j.scitotenv.2015.11.113.
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Pan, Yuqing, Lei Duan, Mingqi Li, Pinqing Song, Nan Xv, Jing Liu, Yifei Le, et al. "Widespread missing super-emitters of nitrogen oxides across China inferred from year-round satellite observations." Science of The Total Environment 864 (March 2023): 161157. http://dx.doi.org/10.1016/j.scitotenv.2022.161157.
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Liu, Mingxu, Xin Huang, Yu Song, Jie Tang, Junji Cao, Xiaoye Zhang, Qiang Zhang, et al. "Ammonia emission control in China would mitigate haze pollution and nitrogen deposition, but worsen acid rain." Proceedings of the National Academy of Sciences 116, no. 16 (April 1, 2019): 7760–65. http://dx.doi.org/10.1073/pnas.1814880116.
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China has been experiencing fine particle (i.e., aerodynamic diameters ≤ 2.5 µm; PM2.5) pollution and acid rain in recent decades, which exert adverse impacts on human health and the ecosystem. Recently, ammonia (i.e., NH3) emission reduction has been proposed as a strategic option to mitigate haze pollution. However, atmospheric NH3 is also closely bound to nitrogen deposition and acid rain, and comprehensive impacts of NH3 emission control are still poorly understood in China. In this study, by integrating a chemical transport model with a high-resolution NH3 emission inventory, we find that NH3 emission abatement can mitigate PM2.5 pollution and nitrogen deposition but would worsen acid rain in China. Quantitatively, a 50% reduction in NH3 emissions achievable by improving agricultural management, along with a targeted emission reduction (15%) for sulfur dioxide and nitrogen oxides, can alleviate PM2.5 pollution by 11−17% primarily by suppressing ammonium nitrate formation. Meanwhile, nitrogen deposition is estimated to decrease by 34%, with the area exceeding the critical load shrinking from 17% to 9% of China’s terrestrial land. Nevertheless, this NH3 reduction would significantly aggravate precipitation acidification, with a decrease of as much as 1.0 unit in rainfall pH and a corresponding substantial increase in areas with heavy acid rain. An economic evaluation demonstrates that the worsened acid rain would partly offset the total economic benefit from improved air quality and less nitrogen deposition. After considering the costs of abatement options, we propose a region-specific strategy for multipollutant controls that will benefit human and ecosystem health.
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Wang, Y., Q. Q. Zhang, K. He, Q. Zhang, and L. Chai. "Sulfate-nitrate-ammonium aerosols over China: response to 2000–2015 emission changes of sulfur dioxide, nitrogen oxides, and ammonia." Atmospheric Chemistry and Physics Discussions 12, no. 9 (September 17, 2012): 24243–85. http://dx.doi.org/10.5194/acpd-12-24243-2012.
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Abstract. We use a chemical transport model to examine the change of sulfate-nitrate-ammonium (SNA) aerosols over China due to anthropogenic emission changes of their precursors (SO2, NOx and NH3) from 2000 to 2015. From 2000 to 2006, annual mean SNA concentrations increased by about 60% over China as a result of the 60%~80% increases in SO2 and NOx emissions. During this period, sulfate is the dominant component of SNA over South China (SC) and Sichuan Basin (SCB), while nitrate makes equal contribution as sulfate over North China (NC). Based on emission reduction targets in the 12th (2011–2015) Five Year Plan (FYP), China's total SO2 and NOx emissions are projected to change by −16% and +16% from 2006 to 2015, respectively. However, the amount of NH3 emissions in 2015 is uncertain, given our finding that bottom-up inventories tend to overestimate China's ammonia emissions during the 2000–2006 period. With no change in NH3 emissions, SNA mass concentrations in 2015 will decrease over SCB and SC compared to their levels in 2006, but increase over NC where the magnitude of nitrate increase exceeds that of sulfate reduction. This suggests that the SO2 emission reduction target set by the 12th FYP, although effective in reducing SNA over SC and SCB, will not be successful over NC for which NOx emission control needs to be strengthened. If NH3 emissions are allowed to keep their recent growth rate and increase by +16% from 2006 to 2015, the benefit of SO2 reduction will be completely offset over all of China due to the significant increase of nitrate, demonstrating the critical role of NH3 in regulating nitrate. The effective strategy to control SNA and hence PM2.5 pollution over China should thus be based on improving understanding of current NH3 emissions and putting more emphasis on controlling NH3 emissions in the future.
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Benish, Sarah E., Hao He, Xinrong Ren, Sandra J. Roberts, Ross J. Salawitch, Zhanqing Li, Fei Wang, et al. "Measurement report: Aircraft observations of ozone, nitrogen oxides, and volatile organic compounds over Hebei Province, China." Atmospheric Chemistry and Physics 20, no. 23 (November 30, 2020): 14523–45. http://dx.doi.org/10.5194/acp-20-14523-2020.
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Abstract. To provide insight into the planetary boundary layer (PBL) production of ozone (O3) over the North China Plain, the Air chemistry Research in Asia (ARIAs) campaign conducted aircraft measurements of air pollutants over Hebei Province, China, between May and June 2016. We evaluate vertical profiles of trace gas species including O3, nitrogen oxides (NOx), carbon monoxide (CO), and volatile organic compounds (VOCs) and relate to rates of O3 production. This analysis shows measured O3 levels ranged from 45 to 146 ppbv, with the peak median concentration (∼ 92 ppbv) occurring between 1000 and 1500 m. The NOx concentrations exhibited strong spatial and altitudinal variations, with a maximum of 53 ppbv. Ratios of CO∕CO2 indicate the prevalence of low-efficiency combustion from biomass burning and residential coal burning but indicate some success of regional pollution controls compared to earlier studies in China. Concentrations of total measured VOCs reveal alkanes dominate the total measured volume mixing ratio of VOCs (68 %), and sources include vehicular emissions, fuel and solvent evaporation, and biomass burning. Alkanes and alkenes/alkynes are responsible for 74 % of the total VOC reactivity assessed by calculating the OH loss rates, while aromatics contribute the most to the total ozone formation potential (OFP) (43 %) with toluene, m/p-xylene, ethylene, propylene, and i-pentane playing significant roles in the aloft production of O3 in this region. In the PBL below 500 m, box model calculations constrained by measured precursors indicate the peak rate of mean O3 production was ∼ 7 ppbv h−1. Pollution frequently extended above the PBL into the lower free troposphere around 3000 m, where NO2 mixing ratios (∼ 400 pptv) led to net production rates of O3 up to ∼ 3 ppbv h−1; this pollution can travel substantial distances downwind. The O3 sensitivity regime is determined to be NOx-limited throughout the PBL, whereas it is more VOC-limited at low altitudes near urban centers, demonstrating that control of both VOCs and NOx is needed to reduce aloft O3 pollution over Hebei.
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Lin, J. T., Z. Liu, Q. Zhang, H. Liu, J. Mao, and G. Zhuang. "Model uncertainties affecting satellite-based inverse modeling of nitrogen oxides emissions and implications for surface ozone simulation." Atmospheric Chemistry and Physics Discussions 12, no. 6 (June 7, 2012): 14269–327. http://dx.doi.org/10.5194/acpd-12-14269-2012.
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Abstract. Errors in chemical transport models (CTMs) interpreting the relation between space-retrieved tropospheric column densities of nitrogen dioxide (NO2) and emissions of nitrogen oxides (NOx) have important consequences on the inverse modeling. They are however difficult to quantify due to lack of adequate in situ measurements, particularly over China and other developing countries. This study proposes an alternate approach for model evaluation over East China, by analyzing the sensitivity of modeled NO2 columns to errors in meteorological and chemical parameters/processes important to the nitrogen abundance. As a demonstration, it evaluates the nested version of GEOS-Chem driven by the GEOS-5 meteorology and the INTEX-B anthropogenic emissions and used with retrievals from the Ozone Monitoring Instrument (OMI) to constrain emissions of NOx. The CTM has been used extensively for such applications. Errors are examined for a comprehensive set of meteorological and chemical parameters using measurements and/or uncertainty analysis based on current knowledge. Results are exploited then for sensitivity simulations perturbing the respective parameters, as the basis of the following post-model linearized and localized first-order modification. It is found that the model meteorology likely contains errors of various magnitudes in cloud optical depth, air temperature, water vapor, boundary layer height and many other parameters. Model errors also exist in gaseous and heterogeneous reactions, aerosol optical properties and emissions of non-nitrogen species affecting the nitrogen chemistry. Modifications accounting for quantified errors in 10 selected parameters increase the NO2 columns in most areas with an average positive impact of 22% in July and 10% in January. This suggests a possible systematic model bias such that the top-down emissions will be overestimated by the same magnitudes if the model is used for emission inversion without corrections. The modifications however cannot account for the large model underestimates in cities and other extremely polluted areas (particularly in the north) as compared to satellite retrievals, likely pointing to underestimates of the a priori emission inventory in these places with important implications for understanding of atmospheric chemistry and air quality. Post-model modifications also have large impacts on surface ozone concentrations with the peak values in July over North China decreasing by about 15 ppb. Individually, modification for the uptake of the hydroperoxyl radical on aerosols has the largest impact for both NO2 and ozone, followed by various other parameters important for some species in some seasons. Note that these modifications are simplified and should be used with caution for error apportionment.
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He, Xianhui, Yung-ho Chiu, Tzu-Han Chang, Tai-Yu Lin, and Zebin Wang. "The Energy Efficiency and the Impact of Air Pollution on Health in China." Healthcare 8, no. 1 (February 3, 2020): 29. http://dx.doi.org/10.3390/healthcare8010029.
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The rapid growth of China’s economy in recent years has greatly improved its citizens’ living standards, but economic growth consumes many various energy sources as well as produces harmful air pollution. Nitrogen oxides, SO2 (sulfur dioxide), and other polluting gases are damaging the environment and people’s health, with a particular spike in incidences of many air pollution-related diseases in recent years. While there have been many documents discussing China’s energy and environmental issues in the past, few of them analyze economic development, air pollution, and residents’ health together. Therefore, this study uses the modified undesirable dynamic two-stage DEA (data envelopment analysis) model to explore the economic, environmental, and health efficiencies of 30 provinces in China. The empirical results show the following: (1) Most provinces have lower efficiency values in the health stage than in the production stage. (2) Among the provinces with annual efficiency values below 1, their energy consumption, CO2 (carbon dioxide), and NOx (nitrogen oxide) efficiency values have mostly declined from 2013 to 2016, while their SO2 efficiency values have increased (less SO2 emissions). (3) The growth rate of SO2 efficiency in 2016 for 10 provinces is much higher than in previous years. (4) The health expenditure efficiencies of most provinces are at a lower level and show room for improvement. (5) In most provinces, the mortality rate is higher, but on a decreasing trend. (6) Finally, as representative for a typical respiratory infection, most provinces have a high level of tuberculosis efficiency, indicating that most areas of China are highly effective at respiratory disease governance.
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Lin, J. T. "Satellite constraint for emissions of nitrogen oxides from anthropogenic, lightning and soil sources over East China on a high-resolution grid." Atmospheric Chemistry and Physics Discussions 11, no. 11 (November 7, 2011): 29807–43. http://dx.doi.org/10.5194/acpd-11-29807-2011.
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Abstract. Vertical column densities (VCDs) of tropospheric nitrogen dioxide (NO2) retrieved from space provide valuable information to estimate emissions of nitrogen oxides (NOx) inversely. Accurate emission attribution to individual sources, important both for understanding the global biogeochemical cycling of nitrogen and for emission control, remains difficult. This study presents a regression-based multi-step inversion approach to estimate emissions of NOx from anthropogenic, lightning and soil sources individually for 2006 over East China on a 0.25° long × 0.25° lat grid, employing the DOMINO product version 2 retrieved from the Ozone Monitoring Instrument. The nested GEOS-Chem model for East Asia is used to simulate the seasonal variations of different emission sources and impacts on VCDs of NO2 for the inversion purpose. Sensitivity tests are conducted to evaluate key assumptions embedded in the inversion process. The inverse estimate suggests annual budgets of about 7.1 TgN (±38%), 0.22 TgN (±46%), and 0.40 TgN (±48%) for the a posteriori anthropogenic, lightning and soil emissions, respectively, each about 24% higher than the respective a priori values. The enhancements in anthropogenic emissions are largest in cities and areas with extensive use of coal, particularly in the north in winter, as evident on the high-resolution grid. Derived soil emissions are consistent with recent bottom-up estimates. They are each less than 6% of anthropogenic emissions annually, increasing to about 13% for July. Overall, anthropogenic emissions are found to be the dominant source of NOx over East China with important implications for nitrogen control.
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Mijling, B., R. J. van der A, and Q. Zhang. "Regional nitrogen oxides emission trends in East Asia observed from space." Atmospheric Chemistry and Physics Discussions 13, no. 7 (July 3, 2013): 17519–44. http://dx.doi.org/10.5194/acpd-13-17519-2013.
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Abstract. Due to changing economic activity, emissions of air pollutants in East Asia change rapidly in space and time. Monthly emission estimates of nitrogen oxides derived from satellite observations provide valuable insight in the evolution of anthropogenic activity on a regional scale. We present the first results of a new emission estimation algorithm, specifically designed to use daily satellite observations of column concentrations for fast updates of emissions of short-lived atmospheric constituents on a~mesoscopic scale (~ 0.25° × 0.25°). The algorithm is used to construct a monthly NOx emission time series for 2007–2011 from tropospheric NO2 observations of GOME-2 for East Chinese provinces and surrounding countries. The new emission estimates correspond well with the bottom-up inventory of EDGAR v4.2, but are smaller than the inventories of INTEX-B and MEIC. They reveal a strong positive trend during 2007–2011 for almost all Chinese provinces, related to the country's economic development. We find a 41% increment of NOx emissions in East China during this period, which shows the need to update emission inventories in this region on a regular basis. Negative emission trends are found in Japan and South Korea, which can be attributed to a combined effect of local environmental policy and global economic crises. Analysis of seasonal variation distinguishes between regions with dominant anthropogenic or biogenic emissions. For regions with a mixed anthropogenic and biogenic signature, the opposite seasonality can be used for an estimation of the separate emission contributions. Finally, the non-local concentration/emission relationships calculated by the algorithm are used to quantify the direct effect of regional NOx emissions on tropospheric NO2 concentrations outside the region. For regions such as North Korea and Beijing province, a substantial part of the tropospheric NO2 originates from emissions elsewhere.
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Mijling, B., R. J. van der A, and Q. Zhang. "Regional nitrogen oxides emission trends in East Asia observed from space." Atmospheric Chemistry and Physics 13, no. 23 (December 11, 2013): 12003–12. http://dx.doi.org/10.5194/acp-13-12003-2013.
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Abstract. Due to changing economic activity, emissions of air pollutants in East Asia are changing rapidly in space and time. Monthly emission estimates of nitrogen oxides derived from satellite observations provide valuable insight into the evolution of anthropogenic activity on a regional scale. We present the first results of a new emission estimation algorithm, specifically designed to use daily satellite observations of column concentrations for fast updates of emissions of short-lived atmospheric constituents on a mesoscopic scale (~ 0.25° × 0.25°). The algorithm is used to construct a monthly NOx emission time series for the period 2007–2011 from tropospheric NO2 observations of GOME-2 for East Chinese provinces and surrounding countries. The new emission estimates correspond well with the bottom-up inventory of EDGAR v4.2, but are smaller than the inventories of INTEX-B and MEIC. They reveal a strong positive trend during 2007–2011 for almost all Chinese provinces, related to the country's economic development. We find a 41% increment of NOx emissions in East China during this period, which shows the need to update emission inventories in this region on a regular basis. Negative emission trends are found in Japan and South Korea, which can be attributed to a combined effect of local environmental policy and global economic crises. Analysis of seasonal variation distinguishes between regions with dominant anthropogenic or biogenic emissions. For regions with a mixed anthropogenic and biogenic signature, the opposite seasonality can be used for an estimation of the separate emission contributions. Finally, the non-local concentration/emission relationships calculated by the algorithm are used to quantify the direct effect of regional NOx emissions on tropospheric NO2 concentrations outside the region. For regions such as North Korea and the Beijing municipality, a substantial part of the tropospheric NO2 originates from emissions elsewhere.
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Kong, Xiangke, Chunhui Li, Ping Wang, Guoxin Huang, Zhitao Li, and Zhantao Han. "Soil Pollution Characteristics and Microbial Responses in a Vertical Profile with Long-Term Tannery Sludge Contamination in Hebei, China." International Journal of Environmental Research and Public Health 16, no. 4 (February 15, 2019): 563. http://dx.doi.org/10.3390/ijerph16040563.
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An investigation was made into the effects of tannery sludge on soil chemical properties and microbial communities in a typical soil profile with long-term tannery sludge contamination, North China. The results showed that trivalent chromium (Cr(III)), ammonium, organic nitrogen, salinity and sulfide were the predominant contaminants in tannery sludge. Although the tannery sludge contained high chromium (Cr, 3,0970 mg/kg), the proportion of mobile Cr forms (exchangeable plus carbonate-bound fraction) only accounted for 1.32%. The X-ray diffraction and X-ray photoelectron spectroscopy results further demonstrated that the Cr existed in a stable state of oxides and iron oxides. The alkaline loam soil had a significant retardation effect on the migration of salinity, ammonium, Cr(III) and sulfide, and the accumulation of these contaminants occurred in soils (0–40 cm). A good correlation (R2 = 0.959) was observed between total organic carbon (TOC) and Cr(III) in the soil profile, indicating that the dissolved organic matter from sludge leachate promoted the vertical mobility of Cr(III) via forming Cr(III)-organic complexes. The halotolerant bacteria (Halomonas and Tepidimicrobium) and organic degrading bacteria (Flavobacteriaceae, Tepidimicrobium and Balneola) became the dominant microflora in the soil profile. High contents of salinity, Cr and nitrogen were the main environmental factors affecting the abundance of indigenous microorganisms in soils.
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He, Shixiong, and Lei Jiang. "Identifying convergence in nitrogen oxides emissions from motor vehicles in China: A spatial panel data approach." Journal of Cleaner Production 316 (September 2021): 128177. http://dx.doi.org/10.1016/j.jclepro.2021.128177.
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Tong, Lei, Huiling Zhang, Jie Yu, Mengmeng He, Nengbin Xu, Jingjing Zhang, Feizhong Qian, Jiayong Feng, and Hang Xiao. "Characteristics of surface ozone and nitrogen oxides at urban, suburban and rural sites in Ningbo, China." Atmospheric Research 187 (May 2017): 57–68. http://dx.doi.org/10.1016/j.atmosres.2016.12.006.
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Guo, Zhonglu, Lichao Zhang, Wei Yang, Li Hua, and Chongfa Cai. "Aggregate Stability under Long-Term Fertilization Practices: The Case of Eroded Ultisols of South-Central China." Sustainability 11, no. 4 (February 22, 2019): 1169. http://dx.doi.org/10.3390/su11041169.
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Soil aggregate stability is an important aspect of soil function and health. Fertilization could potentially alter soil properties and thereby affect aggregate stability. To determine which fertilizer is useful for improving soil fertility and stabilizing soil aggregates and thereby reducing soil erodibility, we examined three types of fertilizer, and measured how soil organic carbon, carbohydrates, and related soil properties influenced aggregate stability in eroded Ultisols. Treatments included control (CK), mineral fertilizer nitrogen (N), phosphorus (P), potassium (K) (NPK), fertilizer NPK plus straw (NPKS), and farmyard manure (FYM). Aggregate stability was tested according to Le Bissonnais method, involving three disruptive tests: fast wetting (FW), slow wetting (SW), and mechanical breakdown (WS). Total organic carbon, particulate organic carbon, mineral-associated carbon, and cold-water-soluble carbohydrate, hot-water-soluble carbohydrate, and dilute acid hydrolysable carbohydrate were measured, as well as soil intrinsic properties (including pH, bulk density, iron and aluminum oxides). The 12-year fertilization had a larger effect on aggregate stability and related soil properties in a 0–15 cm soil layer, whereas no effect was evident at a soil depth of 15–40 cm. MWD (mean weight diameter) under the three tests decreased with increasing soil depth. Fertilization, especially farmyard manure evidently improved MWDFW and MWDWS at a depth of 0–15 cm. Slaking was the main mechanism of aggregate breakdown in Ultisols studied, followed by mechanical breakdown. Correlation analysis showed that MWDFW and MWDWS at a depth of 0–15 cm increased with the increase of particulate organic carbon, total organic carbon, hot-water-soluble carbohydrate and pH. Furthermore, their interaction with amorphous iron oxides enhanced aggregate stability against slaking or, with amorphous aluminum oxides, modified aggregate stability against mechanical breakdown. Consequently, particulate organic carbon was the dominant cementing agent for aggregation in Ultisols studied, and its combination with pH, amorphous aluminum oxides, amorphous iron oxides, and free aluminum oxides play a synergetic role in stabilizing soil aggregate. Accordingly, farmyard manure or fertilizer NPK plus straw improved soil fertility and the ability to resist slaking.
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Liu, Shiwen, Hongxiong Li, Wen Kun, Zhen Zhang, and Haotian Wu. "How Do Transportation Influencing Factors Affect Air Pollutants from Vehicles in China? Evidence from Threshold Effect." Sustainability 14, no. 15 (August 1, 2022): 9402. http://dx.doi.org/10.3390/su14159402.
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In recent years, China has promoted a series of legal norms to reduce the environmental impact of air pollutants from vehicles. The three main vehicle emission species (carbon monoxide, hydrocarbons, nitrogen oxides) contribute significantly to air pollution. In this study, the emission factor method was used to estimate air pollutants from vehicles in 31 provinces from 2006 to 2016. The results show a trend of total vehicle carbon monoxide (CO) and hydrocarbons (HC) emissions decreasing with time; the vehicle nitrogen oxides (NOx) emission trend is divided into two stages: an upward trend between 2006 and 2012 and a downward trend after 2012. Based on a panel threshold, a regression method was used to divide the vehicle NOx and CO emissions in China into four emission zones: low emissions, medium emissions, high emissions, and extra-high emissions. Vehicle HC emissions were divided into three emission zones, which corresponded to low emissions, medium emissions, and high emissions. Overall, vehicle pollution emission efficiency and per capita GDP have a significant inhibitory effect on the three main air pollutants from vehicles (NOx, HC, CO). Both passenger and freight turnover have significant roles in promoting the three air pollutants from vehicles (NOx, HC, CO). Road density and road carrying capacity have a significant role in promoting vehicle HC and CO emissions. Increasing truck proportion inhibits vehicle CO emissions and promotes vehicle NOx emissions. The urbanization rate has a positive effect on vehicle HC and CO emissions. Moreover, there is obvious heterogeneity in different emission zones of the three air pollutants from vehicles (NOx, HC, CO).
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Cui, Shu Yin, and Jiang Lin Li. "Policies of Energy Conservation and Emission Reduction for the Thermal Power Enterprises in China." Advanced Materials Research 869-870 (December 2013): 371–76. http://dx.doi.org/10.4028/www.scientific.net/amr.869-870.371.
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Thermal power enterprises are not only a major energy consumer, but also a significant emission source of sulfur dioxide (SO2) and nitrogen oxides (NOx). Due to the imbalance between costs and benefits, thermal power enterprises in China are not very active in energy conservation and emission reduction. Therefore, it is imperative to establish a market mechanism and enact more incentive policies related to energy conservation and emission reduction for the thermal power enterprises. The paper summarizes the policies for energy conservation and emission reduction in the thermal power enterprises. Also, based on a few leading indicators, the paper analyzes the progress that China has made during the 11th Five-Year-Plan period. Finally, some suggestions for future work are provided.
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Le, Tianhao, Yuan Wang, Lang Liu, Jiani Yang, Yuk L. Yung, Guohui Li, and John H. Seinfeld. "Unexpected air pollution with marked emission reductions during the COVID-19 outbreak in China." Science 369, no. 6504 (June 17, 2020): 702–6. http://dx.doi.org/10.1126/science.abb7431.
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The absence of motor vehicle traffic and suspended manufacturing during the coronavirus disease 2019 (COVID-19) pandemic in China enabled assessment of the efficiency of air pollution mitigation. Up to 90% reduction of certain emissions during the city-lockdown period can be identified from satellite and ground-based observations. Unexpectedly, extreme particulate matter levels simultaneously occurred in northern China. Our synergistic observation analyses and model simulations show that anomalously high humidity promoted aerosol heterogeneous chemistry, along with stagnant airflow and uninterrupted emissions from power plants and petrochemical facilities, contributing to severe haze formation. Also, because of nonlinear production chemistry and titration of ozone in winter, reduced nitrogen oxides resulted in ozone enhancement in urban areas, further increasing the atmospheric oxidizing capacity and facilitating secondary aerosol formation.
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Fuchs, Hendrik, Zhaofeng Tan, Keding Lu, Birger Bohn, Sebastian Broch, Steven S. Brown, Huabin Dong, et al. "OH reactivity at a rural site (Wangdu) in the North China Plain: contributions from OH reactants and experimental OH budget." Atmospheric Chemistry and Physics 17, no. 1 (January 13, 2017): 645–61. http://dx.doi.org/10.5194/acp-17-645-2017.
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Abstract. In 2014, a large, comprehensive field campaign was conducted in the densely populated North China Plain. The measurement site was located in a botanic garden close to the small town Wangdu, without major industry but influenced by regional transportation of air pollution. The loss rate coefficient of atmospheric hydroxyl radicals (OH) was quantified by direct measurements of the OH reactivity. Values ranged between 10 and 20 s−1 for most of the daytime. Highest values were reached in the late night with maximum values of around 40 s−1. OH reactants mainly originated from anthropogenic activities as indicated (1) by a good correlation between measured OH reactivity and carbon monoxide (linear correlation coefficient R2 = 0.33) and (2) by a high contribution of nitrogen oxide species to the OH reactivity (up to 30 % in the morning). Total OH reactivity was measured by a laser flash photolysis–laser-induced fluorescence instrument (LP-LIF). Measured values can be explained well by measured trace gas concentrations including organic compounds, oxygenated organic compounds, CO and nitrogen oxides. Significant, unexplained OH reactivity was only observed during nights, when biomass burning of agricultural waste occurred on surrounding fields. OH reactivity measurements also allow investigating the chemical OH budget. During this campaign, the OH destruction rate calculated from measured OH reactivity and measured OH concentration was balanced by the sum of OH production from ozone and nitrous acid photolysis and OH regeneration from hydroperoxy radicals within the uncertainty of measurements. However, a tendency for higher OH destruction compared to OH production at lower concentrations of nitric oxide is also observed, consistent with previous findings in field campaigns in China.
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Sun, Jing, Shixin Duan, Baolin Wang, Lei Sun, Chuanyong Zhu, Guolan Fan, Xiaoyan Sun, et al. "Long-Term Variations of Meteorological and Precursor Influences on Ground Ozone Concentrations in Jinan, North China Plain, from 2010 to 2020." Atmosphere 13, no. 6 (June 20, 2022): 994. http://dx.doi.org/10.3390/atmos13060994.
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Ground-level ozone (O3) pollution in the North China Plain has become a serious environmental problem over the last few decades. The influence of anthropogenic emissions and meteorological conditions on ozone trends have become the focus of widespread research. We studied the long-term ozone trends at urban and suburban sites in a typical city in North China and quantified the contributions of anthropogenic and meteorological factors. The results show that urban O3 increased and suburban O3 decreased from 2010 to 2020. The annual 90th percentile of the maximum daily 8-h average of ozone in urban areas increased by 3.01 μgm−3year−1 and, in suburban areas, it decreased by 3.74 μgm−3year−1. In contrast to the meteorological contributions, anthropogenic impacts are the decisive reason for the different ozone trends in urban and suburban areas. The rapid decline in nitrogen oxides (NOX) in urban and suburban areas has had various effects. In urban areas, this leads to a weaker titration of NOX and enhanced O3 formation, while in suburban areas, this weakens the photochemical production of O3. Sensitivity analysis shows that the O3 formation regime is in a transition state in both the urban and suburban areas. However, this tends to be limited to volatile organic compounds (VOCs) in urban areas and to NOX in suburban areas. One reasonable approach to controlling ozone pollution should be to reduce nitrogen oxide emissions while strengthening the control of VOCs.
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Fang, Y. T., K. Koba, X. M. Wang, D. Z. Wen, J. Li, Y. Takebayashi, X. Y. Liu, and M. Yoh. "Anthropogenic imprints on nitrogen and oxygen isotopic composition of precipitation nitrate in a nitrogen-polluted city in southern China." Atmospheric Chemistry and Physics Discussions 10, no. 9 (September 8, 2010): 21439–74. http://dx.doi.org/10.5194/acpd-10-21439-2010.
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Abstract. Nitric acid (HNO3) or nitrate (NO3−) is the dominant sink for reactive nitrogen oxides (NOx = NO + NO2) in the atmosphere. In many Chinese cities, HNO3 is becoming a significant contributor to acid deposition. In the present study, we used the denitrifier method to measure nitrogen (N) and oxygen (O) isotopic composition of NO3− in 113 precipitation samples collected from Guangzhou City in southern China over a two-year period (2008 and 2009). We attempted to better understand the spatial and seasonal variability of atmospheric NOx sources and the NO3− formation pathways in this N-polluted city in the Pearl River Delta region. The δ15N values of NO3− (versus air N2) ranged from −4.9 to +10.1‰, and averaged +3.9‰ in 2008 and +3.3‰ in 2009. Positive δ15N values were observed throughout the year, indicating the anthropogenic contribution of NOx emissions, particularly from coal combustion. Different seasonal patterns of δ15N-NO3− were observed between 2008 and 2009, which might reflect different human activities associated with the global financial crisis and the intensive preparations for the 16th Asian Games. Nitrate δ18O values (versus Vienna Standard Mean Ocean Water) varied from +33.4 to +86.5‰ (average +65.0‰ and +67.0‰ in 2008 and 2009, respectively), a range being lower than those reported for high altitude and polar areas. Several δ18O values were observed lower than the expected minimum of 50‰ at our study site. This was likely caused by the reaction of NO with peroxy radicals; peroxy radicals can compete with O3 to convert NO to NO2, thereby donate O atoms with much lower δ18O value than that of O3 to atmospheric NO3−. Our results highlight that the influence of human activities on atmospheric chemistry can be recorded by the N and O isotopic composition of atmospheric NO3− in a N-polluted city.
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Fang, Y. T., K. Koba, X. M. Wang, D. Z. Wen, J. Li, Y. Takebayashi, X. Y. Liu, and M. Yoh. "Anthropogenic imprints on nitrogen and oxygen isotopic composition of precipitation nitrate in a nitrogen-polluted city in southern China." Atmospheric Chemistry and Physics 11, no. 3 (February 15, 2011): 1313–25. http://dx.doi.org/10.5194/acp-11-1313-2011.
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Abstract. Nitric acid (HNO3) or nitrate (NO3−) is the dominant sink for reactive nitrogen oxides (NOx = NO + NO2) in the atmosphere. In many Chinese cities, HNO3 is becoming a significant contributor to acid deposition. In the present study, we measured nitrogen (N) and oxygen (O) isotopic composition of NO3− in 113 precipitation samples collected from Guangzhou City in southern China over a two-year period (2008 and 2009). We attempted to better understand the spatial and seasonal variability of atmospheric NOx sources and the NO3− formation pathways in this N-polluted city in the Pearl River Delta region. The δ15N values of NO3− (versus air N2) ranged from −4.9 to +10.1‰, and averaged +3.9‰ in 2008 and +3.3‰ in 2009. Positive δ15N values were observed throughout the year, indicating the anthropogenic contribution of NOx emissions, particularly from coal combustion. Different seasonal patterns of δ15N-NO3− were observed between 2008 and 2009, which might reflect different human activities associated with the global financial crisis and the intensive preparations for the 16th Asian Games. Nitrate δ18O values (versus Vienna Standard Mean Ocean Water) varied from +33.4 to +86.5‰ (average +65.0‰ and +67.0‰ in 2008 and 2009, respectively), a range being lower than those reported for high latitude and polar areas. Sixteen percent of δ18O values was observed lower than the expected minimum of +55‰ at our study site. This was likely caused by the reaction of NO with peroxy radicals; peroxy radicals can compete with O3 to convert NO to NO2, thereby donate O atoms with much lower δ18O value than that of O3 to atmospheric NO3−. Our results highlight that the influence of human activities on atmospheric chemistry can be recorded by the N and O isotopic composition of atmospheric NO3− in a N-polluted city.
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Lin, J. T. "Satellite constraint for emissions of nitrogen oxides from anthropogenic, lightning and soil sources over East China on a high-resolution grid." Atmospheric Chemistry and Physics 12, no. 6 (March 23, 2012): 2881–98. http://dx.doi.org/10.5194/acp-12-2881-2012.
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Abstract. Vertical column densities (VCDs) of tropospheric nitrogen dioxide (NO2) retrieved from space provide valuable information to estimate emissions of nitrogen oxides (NOx) inversely. Accurate emission attribution to individual sources, important both for understanding the global biogeochemical cycling of nitrogen and for emission control, remains difficult. This study presents a regression-based multi-step inversion approach to estimate emissions of NOx from anthropogenic, lightning and soil sources individually for 2006 over East China on a 0.25° long × 0.25° lat grid, employing the DOMINO product version 2 retrieved from the Ozone Monitoring Instrument. The inversion is done gridbox by gridbox to derive the respective emissions, taking advantage of differences in seasonality between anthropogenic and natural sources. Lightning and soil emissions are combined together for any given gridbox due to their similar seasonality; and their different spatial distributions are used implicitly for source separation to some extent. The nested GEOS-Chem model for East Asia is used to simulate the seasonal variations of different emission sources and impacts on VCDs of NO2 for the inversion purpose. Sensitivity tests are conducted to evaluate key assumptions embedded in the inversion process. The inverse estimate suggests annual budgets of about 7.1 TgN (±39%), 0.21 TgN (±61%), and 0.38 TgN (±65%) for the a posteriori anthropogenic, lightning and soil emissions, respectively, about 18–23% higher than the respective a priori values. The enhancements in anthropogenic emissions are largest in cities and areas with extensive use of coal, particularly in the north in winter, as evident on the high-resolution grid. Derived soil emissions are consistent with recent bottom-up estimates. They are less than 6% of anthropogenic emissions annually, increasing to about 13% for July. Derived lightning emissions are about 3% of anthropogenic emissions annually and about 10% in July. Overall, anthropogenic emissions are found to be the dominant source of NOx over East China with important implications for nitrogen control.
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Sun, Youwen, Cheng Liu, Mathias Palm, Corinne Vigouroux, Justus Notholt, Qihou Hu, Nicholas Jones, et al. "Ozone seasonal evolution and photochemical production regime in the polluted troposphere in eastern China derived from high-resolution Fourier transform spectrometry (FTS) observations." Atmospheric Chemistry and Physics 18, no. 19 (October 11, 2018): 14569–83. http://dx.doi.org/10.5194/acp-18-14569-2018.
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Abstract. The seasonal evolution of O3 and its photochemical production regime in a polluted region of eastern China between 2014 and 2017 has been investigated using observations. We used tropospheric ozone (O3), carbon monoxide (CO), and formaldehyde (HCHO, a marker of VOCs (volatile organic compounds)) partial columns derived from high-resolution Fourier transform spectrometry (FTS); tropospheric nitrogen dioxide (NO2, a marker of NOx (nitrogen oxides)) partial column deduced from the Ozone Monitoring Instrument (OMI); surface meteorological data; and a back trajectory cluster analysis technique. A broad O3 maximum during both spring and summer (MAM/JJA) is observed; the day-to-day variations in MAM/JJA are generally larger than those in autumn and winter (SON/DJF). Tropospheric O3 columns in June are 1.55×1018 molecules cm−2 (56 DU (Dobson units)), and in December they are 1.05×1018 molecules cm−2 (39 DU). Tropospheric O3 columns in June were ∼50 % higher than those in December. Compared with the SON/DJF season, the observed tropospheric O3 levels in MAM/JJA are more influenced by the transport of air masses from densely populated and industrialized areas, and the high O3 level and variability in MAM/JJA is determined by the photochemical O3 production. The tropospheric-column HCHO∕NO2 ratio is used as a proxy to investigate the photochemical O3 production rate (PO3). The results show that the PO3 is mainly nitrogen oxide (NOx) limited in MAM/JJA, while it is mainly VOC or mixed VOC–NOx limited in SON/DJF. Statistics show that NOx-limited, mixed VOC–NOx-limited, and VOC-limited PO3 accounts for 60.1 %, 28.7 %, and 11 % of days, respectively. Considering most of PO3 is NOx limited or mixed VOC–NOx limited, reductions in NOx would reduce O3 pollution in eastern China.
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Zhang, Qianqian, Yuepeng Pan, Yuexin He, Yuanghong Zhao, Liye Zhu, Xingying Zhang, Xiaojuan Xu, et al. "Bias in ammonia emission inventory and implications on emission control of nitrogen oxides over North China Plain." Atmospheric Environment 214 (October 2019): 116869. http://dx.doi.org/10.1016/j.atmosenv.2019.116869.
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Cheng, Ying, Liqiang He, Weinan He, Pei Zhao, Pinxi Wang, Jin Zhao, Kesong Zhang, and Shaojun Zhang. "Evaluating on-board sensing-based nitrogen oxides (NOX) emissions from a heavy-duty diesel truck in China." Atmospheric Environment 216 (November 2019): 116908. http://dx.doi.org/10.1016/j.atmosenv.2019.116908.
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He, Chuan, Qingyi Xiao, Fangyuan Gong, Yun Yang, and Xipeng Ren. "Functional Materials Based on Active Carbon and Titanium Dioxide in Fog Seal." Materials 13, no. 22 (November 21, 2020): 5267. http://dx.doi.org/10.3390/ma13225267.
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Due to its ability to degrade nitrogen oxides under ultraviolet, titanium dioxide has been applied in asphalt concrete to degrade automobile exhaust in recent years. To highlight the protection of road traffic environmental quality and mitigate automobile exhaust on human health, this study proposes combining titanium dioxide and active carbon into Sand-fog seal to form a pavement coating material with a photocatalytic function. It uses active carbon to reinforce the material’s function, and the coupling agent for modification makes it well dispersed in the Sand-fog seal. The indoor experiments were carried out at 30 °C and relative humidity of 30%. It tested the composite material’s degradation efficiency on nitrogen dioxide in relation to component proportions, coupling agents, and dosages. The study concluded that the optimal photocatalytic efficiency could be achieved when the ratio of active carbon to titanium dioxide is 0.6. After being modified by the titanate coupling agent and through Scanning Electron Microscope tests, it can be seen that materials can be well dispersed into the Sand-fog seal. When the composite material accounts for 10% of the fog seal, it can achieve the optimal photocatalytic efficiency of about 23.9%. The British pendulum tests show it has good skid resistance performance. Half a kilometer of concrete roadway was sprayed with the material coating in Tianjin, China. The photocatalytic experimental road degrades nitrogen oxides better than the original road. The method is feasible for practical implementation.
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Chen, Youfan, Lin Zhang, Daven K. Henze, Yuanhong Zhao, Xiao Lu, Wilfried Winiwarter, Yixin Guo, et al. "Interannual variation of reactive nitrogen emissions and their impacts on PM2.5 air pollution in China during 2005–2015." Environmental Research Letters 16, no. 12 (November 19, 2021): 125004. http://dx.doi.org/10.1088/1748-9326/ac3695.
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Abstract Emissions of reactive nitrogen as ammonia (NH3) and nitrogen oxides (NO x ), together with sulfur dioxide (SO2), contribute to formation of secondary PM2.5 in the atmosphere. Satellite observations of atmospheric NH3, NO2, and SO2 levels since the 2000s provide valuable information to constrain the spatial and temporal variability of their emissions. Here we present a bottom-up Chinese NH3 emission inventory combined with top-down estimates of Chinese NO x and SO2 emissions using ozone monitoring instrument satellite observations, aiming to quantify the interannual variations of reactive nitrogen emissions in China and their contributions to PM2.5 air pollution over 2005–2015. We find small interannual changes in the total Chinese anthropogenic NH3 emissions during 2005–2016 (12.0–13.3 Tg with over 85% from agricultural sources), but large interannual change in top-down Chinese NO x and SO2 emissions. Chinese NO x emissions peaked around 2011 and declined by 22% during 2011–2015, and Chinese SO2 emissions declined by 55% in 2015 relative to that in 2007. Using the GEOS-Chem chemical transport model simulations, we find that rising atmospheric NH3 levels in eastern China since 2011 as observed by infrared atmospheric sounding interferometer and atmospheric infrared sounder satellites are mainly driven by rapid reductions in SO2 emissions. The 2011–2015 Chinese NO x emission reductions have decreased regional annual mean PM2.5 by 2.3–3.8 μg m−3. Interannual PM2.5 changes due to NH3 emission changes are relatively small, but further control of agricultural NH3 emissions can be effective for PM2.5 pollution mitigation in eastern China.
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Lin, J. T., and M. B. McElroy. "Detection from space of a reduction in anthropogenic emissions of nitrogen oxides during the Chinese economic downturn." Atmospheric Chemistry and Physics Discussions 11, no. 1 (January 6, 2011): 193–223. http://dx.doi.org/10.5194/acpd-11-193-2011.
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Abstract. Rapid economic and industrial development in China and relatively weak emission controls have resulted in significant increases in emissions of nitrogen oxides (NOx) in recent years, with the exception of late 2008 to mid 2009 when the economic downturn led to emission reductions detectable from space. Here vertical column densities (VCDs) of tropospheric NO2 retrieved from satellite observations by SCIAMACHY, GOME-2 and OMI (both by KNMI and by NASA) are used to evaluate changes in emissions of NOx from October 2004 to February 2010 identifying impacts of the economic downturn. Data over polluted regions of Northern East China suggest an increase of 27–33% in annual mean VCD of NO2 prior to the downturn, consistent with an increase of 49% in thermal power generation (TPG) reflecting the economic growth. More detailed analysis is used to quantify changes in emissions of NOx in January over the period 2005–2010 when the effect of the downturn was most evident. The GEOS-Chem model is employed to evaluate the effect of changes in chemistry and meteorology on VCD of NO2. This analysis indicates that emissions decreased by 20% from January 2008 to January 2009, close to the reduction of 18% in TPG that occurred over the same interval. A combination of three relatively independent approaches indicates that the economic downturn was responsible for a~reduction in emissions by 9–11% in January 2009 with an additional decrease of 10% attributed to the slow-down in industrial activity associated with the coincident celebration of the Chinese New Year.
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Gu, Dasa, Yuhang Wang, Ran Yin, Yuzhong Zhang, and Charles Smeltzer. "Inverse modelling of NO<sub><i>x</i></sub> emissions over eastern China: uncertainties due to chemical non-linearity." Atmospheric Measurement Techniques 9, no. 10 (October 24, 2016): 5193–201. http://dx.doi.org/10.5194/amt-9-5193-2016.
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Abstract. Satellite observations of nitrogen dioxide (NO2) have often been used to derive nitrogen oxides (NOx = NO + NO2) emissions. A widely used inversion method was developed by Martin et al. (2003). Refinements of this method were subsequently developed. In the context of this inversion method, we show that the local derivative (of a first-order Taylor expansion) is more appropriate than the “bulk ratio” (ratio of emission to column) used in the original formulation for polluted regions. Using the bulk ratio can lead to biases in regions of high NOx emissions such as eastern China due to chemical non-linearity. Inverse modelling using the local derivative method is applied to both GOME-2 and OMI satellite measurements to estimate anthropogenic NOx emissions over eastern China. Compared with the traditional method using bulk ratio, the local derivative method produces more consistent NOx emission estimates between the inversion results using GOME-2 and OMI measurements. The results also show significant changes in the spatial distribution of NOx emissions, especially over high emission regions of eastern China. We further discuss a potential pitfall of using the difference of two satellite measurements to derive NOx emissions. Our analysis suggests that chemical non-linearity needs to be accounted for and that a careful bias analysis is required in order to use the satellite differential method in inverse modelling of NOx emissions.
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Lin, J. T., and M. B. McElroy. "Detection from space of a reduction in anthropogenic emissions of nitrogen oxides during the Chinese economic downturn." Atmospheric Chemistry and Physics 11, no. 15 (August 10, 2011): 8171–88. http://dx.doi.org/10.5194/acp-11-8171-2011.
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Abstract. Rapid economic and industrial development in China and relatively weak emission controls have resulted in significant increases in emissions of nitrogen oxides (NOx) in recent years, with the exception of late 2008 to mid 2009 when the economic downturn led to emission reductions detectable from space. Here vertical column densities (VCDs) of tropospheric NO2 retrieved from satellite observations by SCIAMACHY, GOME-2 and OMI (both by KNMI and by NASA) are used to evaluate changes in emissions of NOx from October 2004 to February 2010 identifying impacts of the economic downturn. Data over polluted regions of Northern East China suggest an increase of 27–33 % in 12-month mean VCD of NO2 prior to the downturn, consistent with an increase of 49 % in thermal power generation (TPG) reflecting the economic growth. More detailed analysis is used to quantify changes in emissions of NOx in January over the period 2005–2010 when the effect of the downturn was most evident. The GEOS-Chem model is employed to evaluate the effect of changes in chemistry and meteorology on VCD of NO2. This analysis indicates that emissions decreased by 20 % from January 2008 to January 2009, close to the reduction of 18 % in TPG that occurred over the same interval. A combination of three independent approaches indicates that the economic downturn was responsible for a reduction in emissions by 9–11 % in January 2009 with an additional decrease of 10 % attributed to the slow-down in industrial activity associated with the coincident celebration of the Chinese New Year; errors in the estimate are most likely less than 3.4 %.
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Yang-shi, Shao, Fan Ding-qiang, Zhang jing-ming, Ren shi-rui, Wang jin-xin, Luo xu-cong, Peng yun-hui, and Hou huan-ran. "Design of wall materials based on waste glass regeneration." MATEC Web of Conferences 175 (2018): 01009. http://dx.doi.org/10.1051/matecconf/201817501009.
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With urban high buildings increasing in China, the demand for efficiency of wall insulation is getting more and more serious, especially in northeast and northwest China. However, thermal insulation wall in domestic is quite easy to produce cracks under external conditions, which greatly reduces life time. In this paper, we expand the discarded glass and mix aggregate and polypropylene fiber to improve the compressive strength of concrete to achieve green multifunctional concrete.Through the performance test of the expansive glass, we conclude that performances of expansive glass become best at the sinter point of 660°;Moreover, TiO2 added to the exterior wall coating can catalyze the degradation of nitrogen oxides and formaldehyde to purify the air. Non-toxic and harmless, the wall, with strong thermal insulation efficiency, is expected to replace the current building materials in order to produce and utilize massively.
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Yong Ung, Yu, Park Sung Ho, Jung Dong Ho, and Lee Chang Hee. "Improving Liquefied Natural Gas Bunkering in Korea through the Chinese and Japanese Experiences." Sustainability 12, no. 22 (November 17, 2020): 9585. http://dx.doi.org/10.3390/su12229585.
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The International Maritime Organization has strengthened global environmental regulations related to sulfur and nitrogen oxides contained in ship fuel oil since the beginning of 2020. One strategy to comply with the regulations is to fuel ships with liquefied natural gas (LNG) rather than with traditional heavy fuel oil. China and Japan are both developing a business structure for the bunkering of LNG through public–private partnerships to expand their leadership in the field in Northeast Asia and secure a competitive advantage. Compared to China and Japan, Korea has relatively inadequate laws, policy support, and best practices for safe and efficient LNG bunkering for ships. This article provides a comprehensive overview of the LNG bunkering regulation systems in China and Japan and addresses how these systems can be mirrored by Korea to improve the Korean system. It compares the legislative and normative rules of China and Japan regarding the complex global scenario of maritime transportation. The results show that Korea must revise its guidelines and create the advanced institutional framework required for the LNG bunkering market to support an eco-friendly shipping industry and maintain a competitive edge against China and Japan.
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Li, Ke, Daniel J. Jacob, Hong Liao, Yulu Qiu, Lu Shen, Shixian Zhai, Kelvin H. Bates, et al. "Ozone pollution in the North China Plain spreading into the late-winter haze season." Proceedings of the National Academy of Sciences 118, no. 10 (March 1, 2021): e2015797118. http://dx.doi.org/10.1073/pnas.2015797118.
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Surface ozone is a severe air pollution problem in the North China Plain, which is home to 300 million people. Ozone concentrations are highest in summer, driven by fast photochemical production of hydrogen oxide radicals (HOx) that can overcome the radical titration caused by high emissions of nitrogen oxides (NOx) from fuel combustion. Ozone has been very low during winter haze (particulate) pollution episodes. However, the abrupt decrease of NOx emissions following the COVID-19 lockdown in January 2020 reveals a switch to fast ozone production during winter haze episodes with maximum daily 8-h average (MDA8) ozone concentrations of 60 to 70 parts per billion. We reproduce this switch with the GEOS-Chem model, where the fast production of ozone is driven by HOx radicals from photolysis of formaldehyde, overcoming radical titration from the decreased NOx emissions. Formaldehyde is produced by oxidation of reactive volatile organic compounds (VOCs), which have very high emissions in the North China Plain. This remarkable switch to an ozone-producing regime in January–February following the lockdown illustrates a more general tendency from 2013 to 2019 of increasing winter–spring ozone in the North China Plain and increasing association of high ozone with winter haze events, as pollution control efforts have targeted NOx emissions (30% decrease) while VOC emissions have remained constant. Decreasing VOC emissions would avoid further spreading of severe ozone pollution events into the winter–spring season.
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Wang, Xiaojie, Benjuan Liu, Jing Ma, Yanhui Zhang, Tianlong Hu, Heng Zhang, Yucheng Feng, et al. "Soil aluminum oxides determine biological nitrogen fixation and diazotrophic communities across major types of paddy soils in China." Soil Biology and Biochemistry 131 (April 2019): 81–89. http://dx.doi.org/10.1016/j.soilbio.2018.12.028.
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