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Contrasting trends of PM2.5 and surface-ozone concentrations in China from 2013 to 2017

National Science Review 2020年第8期7卷 1331-1339页

作者： Yonghong Wang Wenkang Gao Shuai Wang Tao Song Zhengyu Gong Dongsheng Ji Lili Wang Zirui Liu Guiqian Tang Yanfeng Huo Shili Tian Jiayun Li Mingge Li Yuan Yang Biwu Chu Tuukka Pet?j? Veli-Matti Kerminen Hong He Jiming Hao Markku Kulmala Yuesi Wang Yuanhang Zhang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC) Institute of Atmospheric Physics Chinese Academy of Sciences Institute for Atmospheric and Earth System Research University of Helsinki China National Environmental Monitoring Center (CNEMC) Anhui Institute of Meteorological Sciences State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University

Although much attention has been paid to investigating and controlling air pollution in China, the trends of air-pollutant concentrations on a national scale have remained unclear. Here, we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017, during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions. Our results show a significant decreasing trend in the PM2.5concentration in heavily polluted regions of eastern China, with an annual decrease of ～7% compared with measurements in 2013. The measured decreased concentrations of SO2, NO2and CO（a proxy for anthropogenic volatile organic compounds） could explain a large fraction of the decreased PM2.5concentrations in different regions. As a consequence, the heavily polluted days decreased significantly in corresponding regions. Concentrations of organic aerosol,nitrate, sulfate, ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017, connecting the decreases in aerosol precursors with corresponding chemical components closely. However, surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017, which indicates stronger photochemical pollution. The boundary-layer height in capital cities of eastern China showed no significant trends over the Beijing–Tianjin–Hebei, Yangtze River Delta and Pearl River Delta regions from 2013 to 2017, which confirmed the reduction in anthropogenic emissions. Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017, although the ozone concentration has increased significantly, suggesting a more complex mechanism of improving Chinese air quality in the future.

关键词： air pollution clean-air action particulate matter surface ozone China chemical composition

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Molecular characterization of oxidized organic nitrogen in the polluted urban atmosphere of Beijing

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Science of the Total Environment 2024年 955卷 177109页

作者： Liu, Lei Sun, Junying Shen, Xiaojing Cheng, Xi Chen, Qi Liu, Quan Zhang, Yangmei Zheng, Jing Wen, Wei Ma, Xin State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological Sciences Beijing100081 China State Key Joint Laboratory of Environmental Simulation and Pollution Control BIC-ESAT and IJRC College of Environmental Sciences and Engineering Peking University Beijing100871 China Beijing100083 China School of Energy and Environmental Engineering University of Science and Technology Beijing Beijing100083 China CMA Earth System Modeling and Prediction Centre Beijing100081 China

Oxidized organic nitrogen (OON) serves as a crucial link between volatile organic compounds (VOCs), nitrogen oxides, ozone, and secondary organic aerosol (SOA). However, the comprehension of the molecular composition, formation mechanism, and implications of OON remains limited, particularly in urban environments influenced heavily by anthropogenic emissions. This study presents the field measurements of OON conducted at an urban site in Beijing using chemical ionization mass spectrometry with nitrate as the reagent ion. The molecular characteristics, dominant species, and oxidation states of OON were investigated. Positive matrix factorization analysis disentangled the diverse OON into factors characterized by unique fingerprint features and formation pathways. A modified workflow was used to classify the majority of OON as terpene (3.0 %), isoprene (15.2 %), aliphatic (38.1 %, containing dinitrate), and aromatic (36.0 %, containing aromatic ring retaining) OON. This highlights the significant impact of anthropogenic sources and underscores the need for stringent controls on anthropogenic VOC emissions to mitigate OON formation. Volatility estimates further indicate that aromatic and aliphatic OON, with relatively low volatility, are expected to be the primary contributors to SOA formation by condensation or gas-particle partitioning in urban Beijing. In addition, hazy weather conditions may facilitate multi-generation reactions, leading to the production of large amounts of semi-volatile dinitrate OON and promoting its conversion to SOA. © 2024 Elsevier B.V.

关键词： Aromatization

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全球变暖导致易诱发臭氧污染的强地面太阳辐射频率增加

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Science Bulletin 2023年第4期68卷 388-392,M0003页

作者：寇文彬高阳张绍晴蔡文炬耿冠楠 Steven J.Davis 王宏郭修文程文轩曾欣然马铭晨王厚文王俏巧姚小红高会旺吴立新 Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Environmental Science and EcologyMinistry of EducationOcean University of ChinaQingdao 266100China Laboratory for Ocean Dynamics and Climate Laoshan LaboratoryQingdao 266237China Key Laboratory of Physical Oceanography Institute for Advanced Ocean StudyFrontiers Science Center for Deep Ocean Multispheres and Earth SystemCollege of Oceanic and Atmospheric SciencesOcean University of ChinaQingdao 266100China Key Laboratory of Physical Oceanography–Institute for Advanced Ocean Studies Ocean University of ChinaLaoshan LaboratoryQingdao 266100China Commonwealth Scientific and Industrial Research Organisation Marine and Atmospheric Research Aspendale Victoria 3195Australia State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Department of Earth System Science University of CaliforniaIrvine CA 92697USA College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China Institute for Environmental and Climate Research Jinan UniversityGuangzhou 510000China

世界卫生组织2021年提出了新的臭氧标准,不仅加严了原有的短期暴露标准,还增加了暖季峰值的长期暴露指标.2019年秋季我国发生了大范围臭氧污染事件,特别是珠三角地区臭氧浓度异常增加最为突出,导致其暖季峰值超标,并且2019年长时间臭氧... 详细信息

世界卫生组织2021年提出了新的臭氧标准,不仅加严了原有的短期暴露标准,还增加了暖季峰值的长期暴露指标.2019年秋季我国发生了大范围臭氧污染事件,特别是珠三角地区臭氧浓度异常增加最为突出,导致其暖季峰值超标,并且2019年长时间臭氧污染事件增幅更大.本文发现地面太阳辐射与臭氧年际变化相关性远高于其他气象因子,即使在温度较低时,较强的太阳辐射依然可促进高臭氧浓度累积.数值模式显示强太阳辐射驱动天然源大幅增加,不仅促进臭氧浓度升高,更重要的是,对于长时间臭氧污染事件频率增加大于短期污染事件,从而大大促进臭氧超标天数的增加.结合高分辨率地球系统模式和多模式比较计划,一致揭示在全球变暖下中国东部、美国东南部、欧洲各国,未来地面太阳辐射显著增加.通过将秋季地面太阳辐射日异常标准化,构建了臭氧气象指数,可有效揭示高臭氧浓度,阐明在北半球多个易发生臭氧污染区域,高臭氧气象指数天气发生频率显著增加,即利于高臭氧污染发生的气象条件在全球变暖下可能会更加频繁地发生.

关键词：臭氧浓度全球变暖天然源美国东南部气象指数臭氧污染气象条件短期暴露

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Optimization Charging Method of Lithium-Ion Battery Based on Multi-Objective Bbo Algorithm

SSRN

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SSRN 2024年

作者： Duan, Shuangming Xia, Kuifeng Li, Junhui Zhao, Zhiqiang Liu, Haojun Key Laboratory of Modern Power System Simulation Control and New Green Energy Technology Ministry of Education Northeast Electricity Power University Jilin Jilin132012 China State Grid Hami Power Supply Company Xinjiang Uygur Autonomous Region Hami839000 China

Currently, the charging strategy of lithium-ion battery is usually an open-loop method, which lacks feedback in the charging process. In order to obtain a suitable charging strategy for lithium-ion battery, a simple and easy PID closed-loop constant temperature control system is proposed, which takes the temperature of lithium-ion battery as the feedback quantity, and improves the charging speed under the condition that the maximum temperature rise of lithium-ion battery is consistent. Secondly, SOC-based Multistage Constant Current (SMCC) based on SOC segmentation is proposed and orthogonal experiments are constructed by Taguchi method to determine the constant current values of each SMCC segment. Then, taking charging time, charging efficiency and SOH (State of Health) decay as the charging objectives to be optimized, multi-objective biogeographic-based optimization (BBO) is used. The MBBO algorithm optimizes each charging current under different weight coefficient combinations. According to the optimization results, Pareto optimal frontier is used to select the most balanced charging strategy from the six proposed charging strategies. Finally, SMCC charging current optimized by MBBO algorithm is connected to PID closed-loop constant temperature control system, and compared with SMCC charging strategy without constant temperature control and traditional 1C-CCCV method, the results show that compared with 1C-CCV charging strategy, The algorithm optimized SMCC can significantly reduce the charging time and SOH loss of lithium-ion batteries, and the SMCC charging current can be connected to PID closed-loop constant temperature control to further improve the charging speed, and keep the charging efficiency basically equal to the SOH attenuation. © 2024, The Authors. All rights reserved.

关键词： Taguchi methods

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High Abundance of Atmospheric Sulfonates Derived from Light-Duty Gasoline Vehicles

ACS ES&T Air

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ACS ES&T Air 2025年第4期2卷 607-614页

作者： Shuang Chen Huixia Han Lihong Ren Yisheng Xu Libin Wu Yuanguan Gao Yuanbi Yi Xinping Yang Mingliang Fu Hang Yin Yan Ding Pingqing Fu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China；School of Earth System Science Tianjin University Tianjin 300072 China School of Earth System Science Tianjin University Tianjin 300072 China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau The Hong Kong University of Science and Technology Hong Kong SAR China State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation Chinese Research Academy of Environmental Sciences Beijing 100012 China

Particulate matter (PM) emissions from light-duty gasoline vehicles (LDGV) pose a threat to both air quality and human health. However, the molecular compositions and chemical properties of these complex mixtures are poorly understood. In this study, we performed a detailed characterization of exhaust PM from LDGV at various speed phases at the molecular level by employing ultra-high-resolution Fourier transform ion cyclotron resonance mass spectrometry. We found that with increasing speed, the number of organic compounds increased significantly, especially organic nitrogen-containing and sulfur-containing compounds. Moreover, the increase of speed leads to high temperature and high pressure in the cylinder, which in turn leads to a series of thermal cracking–polymerization–cyclization reactions, resulting in new particulate matter with more aromatic structures. In addition, considerable intermediate volatility organic compounds and semivolatile organic compounds were identified in the exhaust PM. Notably, we observed the presence of sulfonates in tailpipe particulate matter during low- or high-speed phases, which highlights a previously negligible source of organic sulfonates in the atmosphere.

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Improvement of the Electrical Properties of Silicone Rubber Doped with Nano-zirconia Grafted by Voltage Stabilizer

Improvement of the Electrical Properties of Silicone Rubber ...

引用

International Conference on Electrical Materials and Power Equipment (ICEMPE)

作者： Xiaoqian Zhu Yuanxiang Zhou Yunxiao Zhang Ming Chen Xuanhao Liu State Key Lab of Control and Simulation of Power System and Generation Equipment & Department of Electrical Engineering Tsinghua University Beijing China College of Electrical Engineering and Automation Fuzhou University Fuzhou China Xiamen Power Supply Company State Grid Fujian Electric Power Company Xiamen China The Wind Solar Storage Division of State Key Laboratory of Control and Simulation of Power System and Generation Equipment School of Electrical Engineering Xinjiang University Urumqi China

Enhancing the electrical performance of silicone rubber (SiR) for cable accessories is noteworthy as they are almost the weakest parts of the cable system. Two types of voltage stabilizers were grafted onto the surface of nano-zirconia (ZrO 2 ) particles, and the grafted nanoparticles were added to the SiR. Measurements such as breakdown strength, and conductivity were carried out to evaluate the electrical performance of SiR nanocomposites. The electrical performance measurement results indicated that the breakdown strength of the nanocomposite SiR improved while the conductance current was reduced. The trap distribution showed that the improvement of the electrical performance of the nanocomposite SiR is mainly due to the decrease of the shallow trap density or the increase of the deep trap density.

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Economic Analysis and Visual simulation Platform Construction of Distributed Energy Storage on Load Peak-shaving and Valley-filling in Distribution Network 4

Economic Analysis and Visual Simulation Platform Constructio...

引用

4th IEEE China International Electrical and Energy Conference, CIEEC 2021

作者： Sun, Zhebin Saren, Gaowa Liang, Tao Li, Hengzhen Liu, Pengxuan Sun, Dapeng Yan, Jiaqi Ma, Dexuan Zhang, Hao Li, Cuiping Li, Junhui Inner Mongolia Power Economic Technology Research Institute Hohhot China Northeast Electric Power University Key Laboratory of Modern Power System Simulation and Control Renewable Energy Technology Ministry of Education Jilin China

ISBN: (纸本)9781728171494

This paper proposes an economic analysis method for distributed energy storage applications in distribution networks, and constructs a visual simulation platform. Firstly, the influence of photovoltaic / wind power fluctuation on load peak-valley difference in distribution network under different permeability is analyzed, and the technical and economic characteristics of different distributed energy storage systems are compared. Secondly, in order to facilitate the analysis and display the analysis results, a visual simulation platform is constructed based on MATLAB / Simulink software. The simulation results of IEEE 33-Bus system show that the method described in this paper can effectively analyze the economy of load peak-shaving and valley-filling by different energy storage configuration methods, and the visualization platform can clearly and intuitively show the results of the above analysis method. © 2021 IEEE.

关键词： MATLAB

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SECONDARY FREQUENCY control OF ISLANDED MICROGRID CONSIDERING WIND AND SOLAR STOCHASTICS

arXiv

引用

arXiv 2023年

作者： Zhong, Cheng Jiang, Zhifu Zhang, Xiangyu Chen, Jikai Li, Yang Key Laboratory of Modern Power System Simulation and Control &Renewable Energy Technology Ministry of Education Northeast Electric Power University Jilin132012 China Northeast Electric Power University College of Electrical Engineering Jilin132012 China

This paper proposed a model predictive control (MPC) secondary frequency control method considering wind and solar power generation stochastics. The extended state-space matrix including unknown stochastic power disturbance is established, and a Kalman filter is used to observe the unknown disturbance. The maximum available power of wind and solar DGs is estimated for establishing real- time variable constraints that prevent DGs output power from exceeding the limits. Through setting proper weight coefficients，wind and photovoltaic DGs are given priority to participate in secondary frequency control. The distributed restorative power of each DG is obtained by solving the quadratic programming (QP) optimal problem with variable constraints. Finally，a microgrid simulation model including multiple PV and wind DGs is built and performed in various scenarios compared to the traditional secondary frequency control method. The simulation results validated that the proposed method can enhance the frequency recovery speed and reduce the frequency deviation，especially in severe photovoltaic and wind fluctuations scenarios. Copyright © 2023, The Authors. All rights reserved.

关键词： Stochastic systems

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Research on Wind Turbine control Hardware in Loop Real-time simulation and its Application

Research on Wind Turbine Control Hardware in Loop Real-time ...

引用

Sustainable Power and Energy Conference (iSPEC)

作者： Guanming Zeng Liang Tu Yihua Zhu Chengxiang Li Mingqun Liu Peng He State Key Laboratory of HVDC and CSG Key Laboratory for Power System Simulation Electric Power Research Institute China Southern Power Grid and National Energy Power Grid Technology R&D Centre and Guangdong Provincial Key Laboratory of Intelligent Operation and Control for New Energy Power System Guangzhou Guangdong Yunnan Power Grid Co. Ltd. Electric Power Research Institute Kunming Yunnan

With the construction of new power system, high-capacity renewable energy sources including wind power are integrated into the power system, whose transient response characteristics have a significant impact on the safe and stable operation of both renewable energy sources and power system. Real-time simulation has become an effective method to study interaction between high-capacity renewable energy sources and power system because of its high accuracy and reliability, and precise wind turbine real-time simulation model is of great significance in research mentioned above. Therefore, the wind turbine control hardware in loop (CHIL) real-time simulation method is proposed in the paper, whose feasibility and accuracy are also verified by comparing simulation data from CHIL platform and on-site testing data. It’s further used in the analysis of large-scale offshore wind farm cluster and connected power system as a practical reference case.

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Short-term power load forecasting method based on CNN-SAEDN-Res

arXiv

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arXiv 2023年

作者： Cui, Yang Zhu, Han Wang, Yijian Zhang, Lu Li, Yang Key Laboratory of Modern Power System Simulation and Control & Renewable Energy Technology Ministry of Education Northeast Electric Power University Jilin132012 China College of Information and Electrical Engineering China Agricultural University Beijing100083 China

In deep learning, the load data with non-temporal factors are difficult to process by sequence models. This problem results in insufficient precision of the prediction. Therefore, a short-term load forecasting method based on convolutional neural network (CNN), self-attention encoder-decoder network (SAEDN) and resi- dual-refinement (Res) is proposed. In this method, feature extraction module is composed of a two-dimensional convolutional neural network, which is used to mine the local correlation between data and obtain high-dimensional data features. The initial load fore-casting module consists of a self-attention encoder-decoder network and a feedforward neural network (FFN). The module utilizes self-attention mechanisms to encode high-dimensional features. This operation can obtain the global correlation between data. Therefore, the model is able to retain important information based on the coupling relationship between the data in data mixed with non-time series factors. Then, self-attention decoding is per-formed and the feedforward neural network is used to regression initial load. This paper introduces the residual mechanism to build the load optimization module. The module generates residual load values to optimize the initial load. The simulation results show that the proposed load forecasting method has advantages in terms of prediction accuracy and prediction stability. Copyright © 2023, The Authors. All rights reserved.

关键词： Convolutional neural networks

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