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Regionalization based on spatial and seasonal variation in ground-level ozone concentrations across China

Journal of Environmental Sciences 2018年第5期30卷 179-190页

作者： Linjun Cheng Shuai Wang zhengyu gong Hong Li Qi Yang Yeyao Wang School of Water Resources and Environment China University of Geosciences China National Environmental Monitoring Center State Environmental Protection Key Laboratory of Quality Control in Environmental Monitoring Lancaster Environment Centre Lancaster University

Owing to the vast territory of China and strong regional characteristic of ozone pollution,it＇s desirable for policy makers to have a targeted and prioritized regulation and ozone pollution control strategy in China based on scientific evidences. It＇s important to assess its current pollution status as well as spatial and temporal variation patterns across China.Recent advances of national monitoring networks provide an opportunity to insight the actions of ozone pollution. Here, we present rotated empirical orthogonal function（REOF）analysis that was used on studying the spatiotemporal characteristics of daily ozone concentrations. Based on results of REOF analysis in pollution seasons for 3 years＇ observations, twelve regions with clear patterns were identified in China. The patterns of temporal variation of ozone in each region were separated well and different from each other, reflecting local meteorological, photochemical or pollution features. A rising trend in annual averaged Eight-hour Average Ozone Concentrations（O3-8 hr） from 2014 to 2016 was observed for all regions, except for the Tibetan Plateau. The mean values of annual and 90 percentile concentrations for all 338 cities were 82.6 ± 14.6 and 133.9 ± 25.8 μg/m3,respectively, in 2015. The regionalization results of ozone were found to be influenced greatly by terrain features, indicating significant terrain and landform effects on ozone spatial correlations. Among 12 regions, North China Plain, Huanghuai Plain, Central Yangtze River Plain, Pearl River Delta and Sichuan Basin were realized as priority regions for mitigation strategies, due to their higher ozone concentrations and dense population.

关键词： Ozone Spatiotemporal variability REOF Regionalizstion

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高效双压氦液化循环研究

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华中科技大学学报（自然科学版） 2024年第4期52卷 143-148页

作者：苏惠坤李正宇龚领会张梅梅中国科学院理化技术研究所航天低温推进剂国家重点实验室北京100190 中国科学院大学北京100190

为了实现氦液化系统的高效性,提出了一种新型双压氦液化循环,探索在相同的高压压力下,流程参数、部件效率、系统液化率及(火用)效率等重要参数随中压压力的变化规律.结果表明:改变中压压力,流程液化率随着中压压力的增加而增加,而(火用... 详细信息

为了实现氦液化系统的高效性,提出了一种新型双压氦液化循环,探索在相同的高压压力下,流程参数、部件效率、系统液化率及(火用)效率等重要参数随中压压力的变化规律.结果表明:改变中压压力,流程液化率随着中压压力的增加而增加,而(火用)效率随之减小,当中压压力为7.0×10^(5)Pa时,液化量为90.46 L/h,(火用)效率达到最大值18.6%,当中压压力为12.5×10^(5)Pa时,液化量和(火用)效率分别为107.4 L/h和17.5%;双压氦液化循环相较于modified-Claude(修正-克劳德)循环,减小了节流阀处的损失,同时降低了系统功耗,提高了系统整体的(火用)效率.

关键词：氦液化器液化循环液化率效率 (火用)分析

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Spatial distribution, seasonal variation and regionalization of PM_(2.5) concentrations in China

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Science China Chemistry 2015年第9期58卷 1435-1443页

作者： Shuai Wang Guogang Li zhengyu gong Li Du Qingtao Zhou Xiaoyan Meng Shuyan Xie Lei Zhou Department of Ambient Air Quality Monitoring China National Environmental Monitoring Center Civil and Environmental Engineering Syracuse University

In order to provide scientific support to policy makers in the regulation of PM2.5 pollution in China, it is important to accurately assess the current status, spatiotemporal characteristics and regionalization data for this air pollutant. An analysis of the pollution status of PM2.5 was conducted using daily averaged mass concentration data recorded in 74 cities in 2013 and 161 cities in 2014. The rotated empirical orthogonal function(REOF) method was applied to analyze this data. Results showed that the average annual PM2.5 concentration in urban areas of China is 62.2±21.5 ?g/m3, and that the distribution is spatially heterogeneous. The North China Plain, middle and lower Yangtze River Plain, Sichuan Basin and Guanzhong Plain had relatively high annual PM2.5 concentrations compared with the southeast coastal region, the Tibetan Plateau and the Yungui Plateau. PM2.5 mass concentrations tended to be higher in winter than in summer, however, the data for many cities showed a small peak in concentrations from May to July. An analysis of the spatial correlation of PM2.5 indicated a significant influence of topographic conditions. A lower correlation was observed where terrain features varied greatly. Based on the results of the REOF analysis and topographic characteristics, ten regions were identified in mid-eastern China, which could be considered as basic pollution prevention divisions for PM2.5; these include the North China Plain region, Pearl River Delta region, Jianghuai Plain region, middle Yangtze River Plain region, Northeast Plain region, Jiangnan coastal region, Sichuan Basin region, Qiantao Plain region, Guanzhong-Central Plain region and Yungui Plateau region. Seasonal variations in the regionalization data were observed, especially for the North China Plain and Pearl River Delta regions. Among the ten regions identified in this study, the North China Plain, Guanzhong-Central Plain, middle Yangtze River Plain and Jianghuai Plain had relatively high PM2.5 mass concentrations in comparison with the other

关键词：颗粒物浓度中国东部空间分布季节变化珠江三角洲地区旋转经验正交函数东南沿海地区 REOF分析

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不同状态方程对于氢热物性预测的对比研究

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低温工程 2024年第3期 8-13页

作者：吴奇杨少柒谢秀娟李正宇龚领会中国科学院低温工程学重点实验室(理化技术研究所) 北京100190 中国科学院大学北京100049 航天低温推进剂技术国家重点实验室北京100190

从状态方程的角度出发,针对不同状态方程在低温高压范围内对于氢热力学性质的预测展开研究,利用目前使用较多的立方型以及多参数状态方程对于氢的PVT数据、等容热容、等压热容、焓、熵等热力学性质进行计算。将计算结果与NIST数据库给... 详细信息

从状态方程的角度出发,针对不同状态方程在低温高压范围内对于氢热力学性质的预测展开研究,利用目前使用较多的立方型以及多参数状态方程对于氢的PVT数据、等容热容、等压热容、焓、熵等热力学性质进行计算。将计算结果与NIST数据库给出的标准值进行比较,并对方程参数进行修正,进一步探讨了各个压力段不同状态方程的优劣以及误差产生的原因,为之后状态方程的使用、改进以及液氢相关设备的设计提出了建议。

关键词：液氢状态方程热力性质饱和超临界

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Trends in particulate matter and its chemical compositions in China from 2013–2017

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Science China Earth Sciences 2019年第12期62卷 1857-1871页

作者： Yuesi WANG Wenjie LI Wenkang GAO Zirui LIU Shili TIAN Rongrong SHEN Dongsheng JI Shuai WANG Lili WANG Guiqian TANG Tao SONG Mengtian CHENG Gehui WANG zhengyu gong Jiming HAO Yuanhang ZHANG State Key Laboratory of Atmospheric Boundary Lacer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China China National Environmental Monitoring Centre Beijing 100012China Key Laboratory of Geographic Information Science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China School of Environment Tsinghua UniversityBeijing 100084China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China University of Chinese Academy of Sciences Beijing 100049China College of Atmospheric Science Lanzhou UniversityLanzhou 730000China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

Accurate determination of the atmospheric particulate matter mass concentration and chemical composition is helpful in exploring the causes and sources of atmospheric enthalpy pollution and in evaluating the rationality of environmental air quality control strategies.Based on the sampling and chemical composition data of PM2.5 in different key regions of China in the CARE-China observation network,this research analyzes the environmental air quality data released by the China National Environmental Monitoring Centre during the studied period to determine the changes in the particulate matter mass concentration in key regions and the evolution of the corresponding chemical compositions during the implementation of the Action Plan for Prevention and Control of Air Pollution from 2013-2017.The results show the following.(1)The particulate matter mass concentration in China showed a significant downward trend;however,the PM2.5 annual mass concentration in 64%of cities exceeds the New Chinese Ambient Air Quality Standard(CAAQS)GradeⅡ(GB3095-2012).The region to the east of the Taihang Mountains,the Fenhe and Weihe River Plain and the Urumqi-Changji regions in Xinjiang,all have PM2.5 concentration loading that is still high,and heavy haze pollution occurred frequently in the autumn and winter.(2)During the heavy pollution in the autumn and winter,the concentrations of sulfate and organic components decreased significantly.The mean SO42-concentration in PM2.5 decreased by 76%,12%,81%and 38%in Beijing-Tianjin-Hebei(BTH),the Pearl River Delta(PRD),the Sichuan-Chongqing region(SC)and the Fenhe and Weihe River Plain,respectively.The mean organic matter(OM)concentration decreased by 70%,44%,48%and 31%,respectively,and the mean concentration of NH4+decreased by 68%,1.6%,38%and 25%,respectively.The mean elemental carbon(EC)concentration decreased by 84%and 20%in BTH and SC,respectively,and it increased by 61%and 11%in the PRD and Fenhe and Weihe River Plain,respectively.The mean concentration of mineral and unresolved chemical

关键词： PM2.5 Action Plan for Prevention and Control of Air Pollution,Key regions Chemical composition Particle size distribution Variation characteristics

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

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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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Strategies to improve aerobic granular sludge stability and nitrogen removal based on feeding mode and substrate

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Journal of Environmental Sciences 2019年第10期31卷 144-154页

作者： Quan Yuan Hui gong Hao Xi Heng Xu zhengyu Jin Nasir Ali Kaijun Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnuironmentTsinghua Uniuersity

A systemic strategy was proposed to improve aerobic granular sludge(AGS)stability and nitrogen(N)removal efficiency by optimizing feeding mode and substrate aiming at complicated wastewater characteristics.Key functional groups at the genus level identified by high-throughput sequencing were evaluated as well.The results showed that anaerobic feeding mode and acetate promoted the compact AGS formation with excellent total nitrogen(TN)removal efficiency(averaging 91.7%±4.1%)at various dissolved oxygen conditions.While the aerobic feeding mode led to a loose AGS structure with a vulnerable anaerobic core and poor TN removal efficiency(averaging58.8%±7.4%).Simultaneous nitrification and denitrification process played the dominant role in N removal in compact AGS over the alternating nitrification and denitrification process.High-concentration glucose undermined feast-famine condition with filamentous bacteria growth out of granule and decreased TN removal efficiency to 67.3%±15.2%.Lower food to microorganism ratio may result in a lower N removal rate attributed to the sharply increased biomass concentration fed by glucose.Ammonia-oxidizing bacteria,nitrite-oxidizing bacteria,denitrifying bacteria,and denitrifying phosphorus accumulation organisms enriched during AGS granulation also contributed to the efficient N removal.The proposed strategy provided insights into the relationship between various factors and stable AGS formation,and systemic operation methods for various complicated wastewater treatment.

关键词： Aerobic granular sludge Feeding mode Substrate N removal Stability

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Medical futility in the era of evidence-based medicine

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The Journal of Biomedical Research 2014年第4期28卷 249-250页

作者： zhengyu Jiang Lu Yang Pinhao Guo Shanshan gong Company Twelve Students Brigadethe Second Military Medical University Department of Foreign Languages the Second Military Medical University

One definition of futility is any treatment that merely preserves permanent unconsciousness or fails to end total dependence of a patient on intensive medical care However, no agreement has ever been reached on what the exact defmition of futility is, as it is not only based on temporary values but also evolves into different subtypes, making it harder to define. The difficulty in dealing with futility problem is how doctors evaluate the futile situation, which is further complicated by lack of standards for specific diseases and experience-based prognosis, leading to subjectivity in evaluation for futility.

关键词： EBM Medical futility in the era of evidence-based medicine

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Autonomy and authority in medical futility

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The Journal of Biomedical Research 2014年第6期28卷 433-434页

作者： zhengyu Jiang Lu Yang Pinhao Guo Shanshan gong Company Twelve Students Brigadethe Second Military Medical University Department of Foreign Languages the Second Military Medical University

Medical futility has been proposed for many years to define the procedure that simply prolongs the suffering of patients but heals nothing.To deal with the decision procedure for treatment,two ideas arise：patients＇autonomy and doctors＇authority.Widely recognized in 1960s,patients＇autonomy respected patients＇willingness over treatment,requiring specific consent for treatment and right to choose during medical procedure.Another idea for futility is doctors＇authority,explained from the paternalistic perspective as well.

关键词： Autonomy and authority in medical futility

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Boosting Zn-ion storage capability of self-standing Zn-doped Co_(3)O_(4)nanowire array as advanced cathodes for high-performance wearable aqueous rechargeable Co//Zn batteries

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Nano Research 2021年第1期14卷 91-99页

作者： Qiulong Li Qichong Zhang zhengyu Zhou Wenbin gong Chenglong Liu Yongbao Feng Guo Hong Yagang Yao College of Materials Science and Engineering Nanjing Tech University30 Puzhu RoadNanjing 211816China National Laboratory of Solid State Microstructuresy College of Engineering and Applied Sciences Jiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Division of Advanced Nanomaterials Key Laboratory of Nanodevices and ApplicationsJoint Key Laboratory of Functional Nanomaterials and DevicesCAS Center for Excellence in NanoscienceSuzhou Institute of Nanotech and NanobionicsChinese Academy of Sciencesy Suzhou 215123China Division of Nanomaterials and Jiangxi Key Lab of Carbonene Materials Suzhou Institute of Nano-Tech and Nano-BionicsNanchangChinese Academy of SciencesNanchang 330200China Department of Chemical and Biomolecular Engineering National University of Singapore4 Engineering Drive 4Singapore 117585Singapore Institute of Applied Physics and Materials Engineering University of Macao.Avenida da UniversidadeTaipaMacao SAR 999078China Department of Physics and Chemistry Faculty of Science and TechnologyUniversity of MacaoAvenida da UniversidadeTaipaMacao SAR 999078China

Neutral aqueous rechargeable Co_(3)O_(4)//Zn batteries with high-output voltage and outstanding cycling stability have yielded new insights into wearable energy-storage devices.To meet the increasing demand for a means of powering wearable and portable devices,the development of a high-performance fiber-shaped Co//Zn battery would be highly desirable.However,the intrinsically poor conductivity of C 03O4 significantly restricts the application of these high-capacity and high-rate aqueous rechargeable battery.Encouragingly,density functional theory(DFT)calculations demonstrate that the substitution of Zn for Co^(3+)leads to an insulatormetal transition in the Zn-doped Co_(3)O_(4)(Zn-Co_(3)O_(4)).In this study,we used metallic Zn-Co_(3)O_(4)nanowire arrays(NWAs)as a novel binder-free cathode to successfully fabricate an all-solid-state fiber-shaped aqueous rechargeable(AFAR)Co//Zn battery.The resulting fiber-shaped Co//Zn battery takes advantage of the enhanced conductivity,increased capacity,and improved rate capability of Zn-Co_(3)O_(4)NWAs to yield a remarkable capacity of 1.25 mAh·cm^(-2)at a current density of 0.5 mA·cm^(-2),extraordinary rate capability(60.8%capacity retention at a high current density of 20 mA·cm^(-2))and an admirable energy density of 772.6 mWh·cm^(-3).Thus,the successful construction of Zn-Co_(3)O_(4)NWAs provides valuable insights into the design of high-capacity and high-rate cathode materials for aqueous rechargeable high-voltage batteries.

关键词： Zn-doped Co_(3)O_(4) aqueous rechargeable Co//Zn battery fiber-shaped high-capacity high-rate

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