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Tropospheric NO_2 vertical column densities retrieved from ground-based MAX-DOAS measurements at Shangdianzi regional atmospheric background station in China

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环境科学学报：英文版 2019年第6期31卷 186-196页

作者： Siyang Cheng Jianzhong Ma Weiping Cheng Peng Yan Huaigang Zhou Liyan Zhou Peng Yang State Key Laboratory of Severe Weather & CMA Key Laboratory of Atmospheric Chemistry Chinese Academy of Meteorological Sciences China Waterborne Transport Research Institute CMA Meteorological Observation Centre Shangdianzi Regional Air Background Station Beijing Meteorological Bureau Meteorological Bureau of Shijiazhuang

Ground-basedMulti-AXis Differential Optical Absorption Spectroscopy(MAX-DOAS)measurements were performed at Shangdianzi(SDZ)regional atmospheric background station in northern China from March 2009 to February 2011.The tropospheric NO_2vertical column densities(VCDs)were retrieved to investigate the background condition of the Beijing–Tianjin–Hebei developed economic circle in China.The seasonal variation of mean NO_2tropospheric VCDs(VCD_(Trop))at SDZ is apparent,with the maximum(1.3×10^(16)molec/cm^2)in February and the minimum(3.5×10^(15)molec/cm^2)in August,much lower than those observed at the Beijing city center.The average daytime diurnal variations of NO_2VCD_(Trop )are rather consistent for all four seasons,presenting the minimum at noon and the higher values in the morning and evening.The largest and lowest amplitudes of NO_2VCD_(Trop)diurnal variation appear in winter and in summer,respectively.The diurnal pattern at SDZ station is similar to those at other less polluted stations,but distinct from the ones at the urban or polluted stations.Tropospheric NO_2VCDs at SDZ are strongly dependent on the wind,with the higher values being associated with the pollution plumes from Beijing city.Tropospheric NO_2VCDs derived from ground-based MAX-DOAS at SDZ show to be well correlated with corresponding OMI(Ozone Monitoring Instrument)satellite products with a correlation coefficient R=0.88.However,the OMI observations are on average higher than MAX-DOAS NO_2VCDs by a factor of 28%,probably due to the OMI grid cell partly covering the south of SDZ which is influenced more by the pollution plumes from the urban areas.

关键词： Ground-basedMAX-DOAS Tropospheric NO2 Satellite validation Pollution plume Regional atmospheric background station

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Characteristics of volatile organic compounds,NO_2,and effects on ozone formation at a site with high ozone level in Chengdu

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Journal of Environmental Sciences 2019年第1期31卷 334-345页

作者： Yuanyuan Deng Jing Li Yaqi Li Rongrong Wu Shaodong Xie College of Environmental Sciences and Engineering State Key Joint Laboratory of Environmental Simulation and Pollution ControlPeking University

Chengdu is a megacity in the southwest of China with high ozone(O_3) mixing ratio.Observation of volatile organic compounds(VOCs), NO_2 and O_3 with high temporal resolution was conducted in Chengdu to investigate the chemical processes and causes of high O_3 levels. The hourly mixing ratios of VOCs, NO2, and O_3 were monitored by an online system from 28 August to 7 October, 2016. According to meteorological conditions,Chengdu, with relative warm weather and low wind speed, is favorable to O_3 formation.Part of the O_3 in Chengdu may be transported from the downtown area. In O_3 episodes,the average mixing ratios of NO_2 and O_3 were 20.20 ppbv and 47.95 ppbv, respectively. In non-O_3 episodes, the average mixing ratios of NO_2 and O_3 were 16.38 ppbv and 35.15 ppbv,respectively. The average mixing ratio of total VOCs(TVOCs) was 40.29 ppbv in non-O_3 episodes, which was lower than that in O_3 episodes(53.19 ppbv). Alkenes comprised51.7% of the total O_3 formation potential(OFP) in Chengdu, followed by aromatics which accounted for 24.2%. Ethylene, trans-pentene, propene, and BTEX(benzene, ethylbenzene,toluene, m/p-xylene, o-xylene) were also major contributors to the OFP in Chengdu. In O_3 episodes, intensive secondary formations were observed during the campaign. Oxygenated VOCs(OVOCs), such as acetone, Methylethylketone(MEK), and Methylvinylketone(MVK)were abundant. Isoprene rapidly converted to MVK and Methacrolein(MACR) during O_3 episodes. Acetone was mainly the oxidant of C3-C5 hydrocarbons.

关键词： Ozone formation VOCs NO2 OFP Diurnal variation

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4d金属掺杂MoS2改善对NO2传感性能的机理研究

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原子与分子物理学报 2025年第2期 181-187页

作者：潘一翠罗磊高鑫付岳牟芷瑶朱洪强冯庆重庆师范大学物理与电子工程学院重庆市光电功能材料重点实验室

二硫化钼(MoS2)是一种热门的气体传感器材料.针对MoS2与气体分子之间的弱相互作用问题，掺杂是一种有效的解决方式.本文利用基于密度泛函理论(DFT)的第一性原理平面波超软赝势计算方法，对二氧化氮(NO2)分子在4d金属掺杂后的MoS2表面上... 详细信息

二硫化钼(MoS2)是一种热门的气体传感器材料.针对MoS2与气体分子之间的弱相互作用问题，掺杂是一种有效的解决方式.本文利用基于密度泛函理论(DFT)的第一性原理平面波超软赝势计算方法，对二氧化氮(NO2)分子在4d金属掺杂后的MoS2表面上吸附的微观机制进行了理论研究.研究结果表明：4d过渡金属元素掺杂有利于提高MoS2吸附NO2后的稳定性，且掺杂改变了材料表面的还原性，改善了其传感性能.掺入4d金属原子的材料禁带宽度显著减小，并且在费米能级附近形成了新的杂质峰，这大大提升了它的导电性.且掺杂原子的4d与5s轨道电子之间的协同作用会提升气体分子与材料之间的传感特性，这表明4d金属原子掺入MoS2可以成为一种有效的NO2传感器材料.本文的工作有助于寻求合适的化学掺杂的方法来提高MoS2基气体传感器的性能.

关键词： MoS2 NO2 吸附掺杂第一性原理计算

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Remote Tracking Gas Molecular via the Standalone-Like Nanosensor-Based Tele-Monitoring System

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Nano-Micro Letters 2021年第2期13卷 207-220页

作者： Han Jin Junkan Yu Daxiang Cui Shan Gao Hao Yang Xiaowei Zhang Changzhou Hua Shengsheng Cui Cuili Xue Yuna Zhang Yuan Zhou Bin Liu Wenfeng Shen Shengwei Deng Wanlung Kam Waifung Cheung Institute of Micro-Nano Science and Technology School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China National Engineering Research Center for Nanotechnology Shanghai 200240People’s Republic of China School of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211People’s Republic of China State Key Laboratory of Pathogen and Biosecurity Institute of Microbiology and EpidemiologyAcademy of Military Medical SciencesBeijing 100071People’s Republic of China Ningbo Materials Science and Technology Institute Chinese Academy of SciencesNingbo 315201People’s Republic of China College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014People’s Republic of China Qi Diagnostics Ltd HongkongPeople’s Republic of China

Remote tracking the variation of air quality in an effective way will be highly helpful to decrease the health risk of human short-and long-term exposures to air pollution.However,high power consumption and poor sensing performance remain the concerned issues,thereby limiting the scale-up in deploying air quality tracking networks.Herein,we report a standalone-like smart device that can remotely track the variation of air pollutants in a power-saving way.Brevity,the created smart device demonstrated satisfactory selectivity(against six kinds of representative exhaust gases or air pollutants),desirable response magnitude(164–100 ppm),and acceptable response/recovery rate(52.0/50.5 s),as well as linear response relationship to NO2.After aging for 2 weeks,the created device exhibited relatively stable sensing performance more than 3 months.Moreover,a photoluminescence-enhanced light fidelity(Li-Fi)telecommunication technique is proposed and the Li-Fi communication distance is significantly extended.Conclusively,our reported standalone-like smart device would sever as a powerful sensing platform to construct high-performance and low-power consumption air quality wireless sensor networks and to prevent air pollutant-induced diseases via a more effective and low-cost approach.

关键词： Metal-organic framework-derived polyhedral ZnO Perovskite quantum dots Nanosensor NO2 Tele-monitoring system

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铁掺杂多孔氧化铟的NO2传感特性

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物理学报 2020年第24期69卷 280-289页

作者：刘志福李培程铁栋黄文江西理工大学电气工程与自动化学院赣州341000 电子科技大学电子科学与工程学院成都610054

研究NO2传感器材料特性和工作机理,对监测大气污染及人体健康保护有重要意义.本文采用水热法合成了铁掺杂的多孔In2O3纳米颗粒,并基于上述纳米颗粒制备了NO2传感器.运用X射线衍射仪、扫描电子显微镜、透射电子显微镜和比表面积测试对所... 详细信息

研究NO2传感器材料特性和工作机理,对监测大气污染及人体健康保护有重要意义.本文采用水热法合成了铁掺杂的多孔In2O3纳米颗粒,并基于上述纳米颗粒制备了NO2传感器.运用X射线衍射仪、扫描电子显微镜、透射电子显微镜和比表面积测试对所制备的纳米颗粒进行微观形貌表征,同时对传感器性能包括温度特性、响应-恢复特性、选择性和稳定性等进行研究.研究发现,当In和Fe摩尔比为9∶1时,由铁掺杂多孔In2O3纳米颗粒制作的传感器对NO2气体具有优秀的选择性和较短的响应-恢复时间.在260℃的工作温度下,传感器对浓度为50 ppm(1 ppm=1 mg/L)的NO2气体的灵敏度值为960.5,响应时间和恢复时间分别为5和6 s.形貌测试结果表明,采用Span-40做活性剂制备的铁掺杂In2O3纳米颗粒为边长50—200 nm的方形结构,其中分布大量细小孔洞,这是导致大的比表面积和高灵敏度的主要原因之一.同时,从空间电荷、内建势垒和掺杂前后能带变化等理论出发,对所制备传感器的传感机理进行了分析.

关键词：铁掺杂In2O3 多孔 NO2 传感器

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MOFs自牺牲模板法制备ZnO及其对NO2的气敏性能

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无机化学学报 2020年第9期36卷 1639-1648页

作者：陈沭璇贾丽华郭祥峰赵振龙杨瑞王欣齐齐哈尔大学化学与化学工程学院精细化工黑龙江省省属高校重点实验室齐齐哈尔161006 广东石油化工学院化学学院茂名525000

以硝酸锌和2,5-二羟基对苯二甲酸为原料,采用溶剂热法制备了Zn-MOF-74,并利用MOFs自牺牲模板法制备了ZnO纳米材料。利用热重-差示扫描量热法(TG-DSC)、X射线衍射(XRD)、红外光谱测试(FT-IR)、X射线光电子能谱测试(XPS)、氮气吸附-脱附... 详细信息

以硝酸锌和2,5-二羟基对苯二甲酸为原料,采用溶剂热法制备了Zn-MOF-74,并利用MOFs自牺牲模板法制备了ZnO纳米材料。利用热重-差示扫描量热法(TG-DSC)、X射线衍射(XRD)、红外光谱测试(FT-IR)、X射线光电子能谱测试(XPS)、氮气吸附-脱附、扫描电镜(SEM)和高倍透射电镜(HRTEM)等方法对合成的样品进行了结构表征。研究了煅烧温度对产物结构、形貌和组成的影响,以及材料的气敏传感性能。结果表明,450℃煅烧Zn-MOF-74制备的六方柱状介孔氧化锌(ZnO450)是由直径约为20 nm的粒子组成的纳米片堆叠形成的,表面残留部分有机官能团,且吸附氧含量明显高于350和550℃处理的样品。基于ZnO450的气敏传感器选择性响应NO2气体,对100 mL·m^-3的NO2气体响应值达到了77.40,是所测试的其他气体响应值的6~105倍,检出限为0.1 mL·m^-3;并且在有SO2等气体共存时,对NO2的响应值基本不变,抗干扰能力强。该传感器对NO2优异的响应能力是由于材料表面吸附氧含量高、比表面积及孔径较大,这些有利于NO2的吸附、表面反应和扩散。

关键词：金属有机框架自牺牲模板法 ZnO 传感器气敏 NO2

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Activity maintenance of the excised branches and a case study of NO_2 exchange between the atmosphere and P.nigra branches

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Journal of Environmental Sciences 2019年第6期31卷 316-326页

作者： Chun Chen Yuzheng Wang Yuanyuan Zhang Xiaoxiu Lun Chengtang Liu Yujing Mu Chenglong Zhang Pengfei Liu Chaoyang Xue Min Song Can Ye Junfeng Liu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Center for Excellence in Urban Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences College of Environmental Science & Engineering Beijing Forest University

The efficient maintenance of the activity of excised branches is the powerful guarantee to accurately determine gas exchange flux between the detached branches of tall trees and the atmosphere. In this study, the net photosynthetic rate(NPR) of the excised branches and branches in situ were measured simultaneously by using two photosynthetic instruments to characterize the activity of the excised branches of Phyllostachys nigra. The ratio of normalized NPR of excised branches to NPR in situ was used to assess the photosynthetic activity of detached branches. Based on photosynthetic activity, an optimal hydroponics protocol for maintaining activity of excised P. nigra branches was presented:1/8 times the concentration of Gamborg B5 vitamin mixture with p H = 6. Under the best cultivation protocol, photosynthetic activity of excised P. nigra branches could be maintained more than 90% within 6 hr in the light intensity range of 200–2000 μmol/(m2·sec) and temperature range of 13.4–28.7°C. The nitrogen dioxide(NO2) flux differences between in situ and in vitro branches and the atmosphere were compared using double dynamic chambers.Based on the maintenance method of excised branches, the NO2 exchange flux between the excised P. nigra branches and the atmosphere(from-1.01 to-2.72 nmol/(m2·sec) was basically consistent with between the branches in situ and the atmosphere(from-1.12 to-3.16 nmol/(m2 sec)) within 6 hr. Therefore, this study provided a feasible protocol for in vitro measurement of gas exchange between tall trees and the atmosphere for a period of time.

关键词： Excised branches Activity maintenance NO2 exchange flux Hydroponics Dynamic chamber

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Long-term observations of tropospheric NO_2, SO_2 and HCHO by MAX-DOAS in Yangtze River Delta area, China

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Journal of Environmental Sciences 2018年第9期30卷 207-221页

作者： Xin Tian Pinhua Xie Jin Xu Ang Li Yang Wang Min Qin Zhaokun Hu School of Environmental Science and Optoeclectronic Technology University of Science and Technology of China Hefei 230026 China. Key laboratory of Environmental Optical and Technology Anhui Institute of Optics and Fine Mechanies Chinese Academy of ScienceHefei 2:30031 China CAS Center for Excellence in Urban Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen361021 China Max Planck Institute for Chemistry Mainz 55128 Germany

Yangtze River Delta （YRD） area is one of the important economic zones in China. However, this area faces increasing environmental problems. In this study, we use ground-based multi-axis differential optical absorption spectroscopy （MAX-DOAS） network in Eastern China to retrieve variations of NO2, SO2, and formaldehyde （HCHO） in the YRD area. Three cities of YRD （Hefei, Nanjing, and Shanghai） were selected for long-term observations. This paper presents technical performance and characteristics of instruments, their distribution in YRD, and results of vertical column densities （VCDs） and profiles of NO2, SO2, and HCHO. Average diurnal variations of tropospheric NO2 and SO2 in different seasons over the three stations yielded minimum values at noon or in the early afternoon, whereas tropospheric HCHO reached the maximum during midday hours. Slight reduction of the pollutants in weekends occurred in all the three sites. In general trace gas concentrations gradually reduced from Shanghai to Hefei. Tropospheric VCDs of NO2, SO2, and HCHO were compared with those from Ozone Monitoring Instrument （OMI） satellite observations, resulting in R2 of 0.606, 0.5432, and 0.5566, respectively. According to analysis of regional transports of pollutants, pollution process happened in YRO under the north wind with the pollution dissipating in the southeast wind. The feature is significant in exploring transport of tropospheric trace gas pollution in YRD, and provides basis for satellite and model validation.

关键词： MAX-DOAS instrument column densities NO2 HCHO SO2 Yangtze River Delta area Pollution transport

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天津机场区域大气NO2及O3影响因子研究

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中国环境科学 2020年第6期40卷 2398-2408页

作者：韩博姚婷玮王立婕孔魏凯何真张铎王愚中国民航大学空中交通管理学院天津市空管运行规划与安全技术重点实验室天津300300 中国民用航空局空中交通管理局运行管理中心北京100022

在紧邻天津机场跑道的点位对机场区域大气常规污染物开展连续监测,应用广义加性模型(GAM),针对2017年3月1日~2018年2月28日间的NO2及O3,识别其影响因子,并确定因子贡献率.选取因子包括环境因子(SO2、NO、NO2、O3、CO、PM2.5、PM10、前... 详细信息

在紧邻天津机场跑道的点位对机场区域大气常规污染物开展连续监测,应用广义加性模型(GAM),针对2017年3月1日~2018年2月28日间的NO2及O3,识别其影响因子,并确定因子贡献率.选取因子包括环境因子(SO2、NO、NO2、O3、CO、PM2.5、PM10、前一小时NO2/O3浓度),气象因子(风向、风速、温度、露点温度、修正海压)及航空活动因子(起飞、着陆).结果显示:机场区域NO2日均值为17.6~123.6μg/m3,超标天数共计38d,占比约13%;O3日均值为1.0~276.1μg/m3,超标天数占比26%,污染主要集中在夏季;环境因子是主要影响因子,累积贡献率在56%~89%;航空活动作为区域重要污染源,对大气NO2、O3存在一定影响,最高贡献率可达20%;气象因子相对贡献较低.全部GAM的Adj-R2为0.85~0.96,筛选的影响因子能够有效解释区域环境空气污染物浓度的变化.

关键词：机场飞机起降 NO2 O3 影响因子广义加性模型

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Enhanced NO_2 gas sensing of a single-layer MoS_2 by photogating and piezo-phototronic effects

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Science Bulletin 2019年第2期64卷 128-135页

作者： Junmeng Guo Rongmei Wen Junyi Zhai Zhong Lin Wang CAS Center for Excellence in Nanoscience Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences School of Nanoscience and Technology University of Chinese Academy of Sciences Center on Nanoenergy Research School of Physical Science and Technology Guangxi University School of Materials Science and Engineering Georgia Institute of Technology

NO_2 sensors with ultrahigh sensitivity are demanded for future electronic sensing systems. However,traditional sensors are considerably limited by the relative low sensitivity, high cost and complicated process. Here, we report a simply and reliable flexible NO_2 sensor based on single-layer MoS_2. The flexible sensor exhibits high sensitivity to NO_2 gas due to ultra-large specific surface area and the nature of two-dimensional(2 D) semiconductor. When the NO_2 is 400 ppb(parts per billion), compared with the dark and strain-free conditions, the sensitivity of the single-layer sensor is enhanced to 671% with a625 nm red light-emitting diode(LED) illumination of 4 mW/cm^2 power under 0.67% tensile strain.More important, the response time is dramatically reduced to $16 s and it only needs $65 s to complete90% recovery. A theoretical model is proposed to discuss the microscopic mechanisms. We find that the remarkable sensing characteristics are the result of coupling among piezoelectricity, photoelectricity and adsorption-desorption induced charges transfer in the single-layer MoS_2 Schottky junction based device.Our work opens up the way to further enhancements in the sensitivity of gas sensor based on single-layer MoS_2 by introducing photogating and piezo-phototronic effects in mesoscopic systems.

关键词： Ultrahigh sensitivity Flexible NO2 sensor Single-layer MoS2 Photogating effect Piezo-phototronic effect

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