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Characteristics of atmospheric nitrous oxide observed at *** GAW global station in the inland Eurasia during eighteen years

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Science china Earth sciences 2024年第1期67卷 92-104页

作者： Miao LIANG Shuangxi FANG lixin LIU Yong ZHANG Jianqiong wang Shuo LIU Hongyang wang Liangchun DENG Meteorological Observation Centre(MOC) China Meteorological Administration(CMA)Beijing 100081China College of Environment Zhejiang University of TechnologyHangzhou 310014China Mt.Waliguan Background Station China Meteorological Administration(CMA)Xining 810001China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Center for Environmental Progress Wuhan 430070China

This study presents atmospheric N_(2)O mole fractions measured from discrete air samples from 2001 to 2018 at ***(WLG)station(36°17′N,100°54′E,3816 m asl)in china,which is a global background station of the World Meteorological Organization/Global Atmosphere Watch Programme(WMO/GAW)in central *** N_(2)O characteristics of annual means,interannual variability,and seasonal cycles were *** results show that N_(2)O at WLG possess a distinct increasing trend and a statistically significant seasonal cycle,with an average growth rate of 0.9±0.01 ppb yr^(−1)(1σ)(1ppb=10^(−9)),which is close to the global *** detrended seasonal cycle shows a trough of−0.25±0.04(1σ)ppb in June and a peak of 0.13±0.07(1σ)ppb in September,with an amplitude of 0.38 *** pattern is due to combined effects of variation in surface sources,vertical convection within the boundary layer and stratosphere to troposphere transportation(STE).The interannual variability in growth rate was partly driven by quasi-biennial oscillation(QBO)of tropical zonal wind through stratospheric transport into the *** to a cluster analysis of back trajectories and the corresponding average N_(2)O load,most air masses cover arid and semi-arid areas in inner Asia with low N_(2)O emissions,indicating that the atmospheric N_(2)O at the WLG represents the background N_(2)O level in central Eurasia.

关键词： Nitrous oxide(N_(2)O) Observation Long-term trend Seasonal variation Interannual variability

Determination of atmospheric concentrations of halocarbons in beijing area

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Journal of Environmental sciences 1993年第1期5卷 76-82页

作者： wang ShaobinResearch Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, chinaPeng lixin and Tang XiaoyanResearch Center of Environmental sciences, Peking University, beijing 100871, china Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Gas chromatography with ambient temperature injection and frozen-trapped techniques was used to determine the atmospheric concentrations of halocarbons over beijing. Halogenated compounds such as CFC-11, CFC-12, CHCl_3, CCl_4, CH_3CCl_3, CHCl =CCl_2, and CCl2=CCl2 were measured and their concentrations are 109±8, 234±13, 47±22, 97±24, 88±29, 11±1 and 17±3 (pptv), respectively.

关键词： GC-ECD atmospheric halocarbons beijing.

Digital virtual flight testing and evaluation method for flight characteristics airworthiness compliance of civil aircraft based on HQRM

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chinese Journal of Aeronautics 2015年第1期28卷 112-120页

作者： Liu Fan wang lixin Tan Xiangsheng School of Aeronautic Science and Engineering Beihang University

In order to incorporate airworthiness requirements for flight characteristics into the entire development cycle of electronic flight control system（EFCS） equipped civil aircraft, digital virtual flight testing and evaluation method based on handling qualities rating method（HQRM）is proposed. First, according to HQRM, flight characteristics airworthiness requirements of civil aircraft in EFCS failure states are determined. On this basis, digital virtual flight testing model,comprising flight task digitized model, pilot controlling model, aircraft motion and atmospheric turbulence model, is used to simulate the realistic process of a pilot controlling an airplane to perform assigned flight tasks. According to the simulation results, flight characteristics airworthiness compliance of the airplane can be evaluated relying on the relevant regulations for handling qualities（HQ） rating. Finally, this method is applied to a type of passenger airplane in a typical EFCS failure state, and preliminary conclusions concerning airworthiness compliance are derived quickly. The research results of this manuscript can provide important theoretical reference for EFCS design and actual airworthiness compliance verification of civil aircraft.

关键词： civil aircraft compliance preliminary verification pilot turbulence realistic passenger concerning

Extratropical Transition and Re-Intensification of Typhoon Toraji(2001):Large-Scale Circulations, Structural Characteristics, and Mechanism Analysis

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Journal of Ocean University of china 2018年第3期17卷 461-476页

作者： ZHU XiANDe WU lixin wang Qi Physical Oceanography Laboratory Ocean University of China College of Oceanic and atmospheric sciences Ocean University of China

With the use of data from the National Centers for Environmental Prediction Climate Forecast System Reanalysis,the environment and structure of typhoon Toraji(2001)are investigated during the re-intensification(RI)stage of its extratropical transition(ET),a process in which a tropical cyclone transforms into an extratropical or mid-latitude *** results provide detailed insight into the ET system and identify the specific features of the system,including wind field,a cold and dry intrusion,and a frontal structure in the RI *** irrotational wind provides the values of upper-and lower-level jets within the transitioning tropical cyclone and the cyclone over Shandong Peninsula,accompanied with the reduced radius of maximum surface winds around the cyclone center in the lower ***,dry air intrusion enhances the formation of fronts and leads to strong potential instability in the southwest and northeast *** distribution of frontogenesis shows that the tilting term associated with vertical motion dominates the positive frontogenesis surrounding the cyclone center,especially in the RI *** diagnostics of the kinetic energy budget suggest that the divergent kinetic energy generation whose time evolution corresponds well to that of cyclone center pressure is the primary factor for the development of Toraji in the lower *** ET of Toraji is a compound pattern that contains a development similar to that of a B-type extratropical cyclone within the maintaining phase and an A-type extratropical cyclone within the strengthening period,which corresponds to the distribution of the E-P fluxes with vertically downward propagation in the maintaining stage and upwards momentum in the strengthening phase.

关键词： typhoon Toraji extratropical transition re-intensification upper level jet frontogenesis energy budget

夜间不同环境稳定性条件下杨树水分生理过程的生物物理控制

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林业科学 2024年第8期60卷 95-108页

作者：王一君陈立欣陈左司南张志强许行姚飞陈胜楠北京林业大学水土保持学院北京100083 北京林业大学生态与自然保护学院北京100083 山西吉县森林生态系统国家野外科学观测研究站临汾042299 国家林业和草原局水土保持与荒漠化防治重点实验室北京100083 北京市共青林场北京101300

【目的】以杨树人工林生态系统为研究对象,研究环境因子与内源性昼夜节律对树木叶片水分生理和树干液流的生物物理调控机制,旨在揭示树木水分生理过程(叶片气孔导度、叶片蒸腾、叶片水势和树干液流)在夜间对不同环境稳定性条件的响应模... 详细信息

【目的】以杨树人工林生态系统为研究对象,研究环境因子与内源性昼夜节律对树木叶片水分生理和树干液流的生物物理调控机制,旨在揭示树木水分生理过程(叶片气孔导度、叶片蒸腾、叶片水势和树干液流)在夜间对不同环境稳定性条件的响应模式和影响因素。【方法】对位于北京市顺义区潮白河沿岸的欧美杨人工林,在生长季期间选定7个晴朗的昼夜,连续监测3棵样树的叶片气体交换和叶片水势。同时,使用热扩散探针技术监测样树的树干液流密度变化,同步记录环境因子变化,并使用日落后历时量化昼夜节律的影响。【结果】1)夜间出现树木气孔开放的现象,叶片蒸腾和液流同步发生。夜间环境稳定(v=0且ΔVPD≤0.1 kPa)条件下,树木水分生理指标主要受大气和土壤温度影响(P0或ΔVPD≥0.1 kPa)条件下,叶片气孔导度和树干液流密度受大气温度(T_(a))和VPD的正向调控,与空气湿度(RH)显著负相关(P<0.05),且T_(a)为主导影响因素。叶水势主要受T_(a)、土壤含水量(SWC)和温度(ST)的共同影响。夜间液流与叶片气孔导度、蒸腾速率和水势显著正相关(R^(2)=0.67)。3)日间环境波动较强,叶片水分生理指标与树干液流密度的相关性显著高于夜间,但叶片气孔导度与VPD呈负相关,且气孔导度与液流密度之间表现出解耦现象(P=0.078)。4)以日落后历时为表征的昼夜节律对树木水分生理指标的作用方式随夜间环境稳定性变化而不同。在夜间环境稳定条件下,日落后历时显著影响叶片气孔导度、叶片水势和叶片蒸腾(P<0.01);而在夜间环境波动条件下,该因子对叶片水分生理指标的影响程度均有所降低且对气孔导度和叶片水势的影响不显著(P_(1)=0.066,P_(2)=0.08),说明夜间环境波动影响了昼夜节律对树木水分生理过程的作用方式和程度。【结论】在夜间不同环境稳定性条件下,树木水分生理的生物物理过程和调控机制有显著差异,当环境因子波动较小时,树木水分生理过程受昼夜节律调控形成了显著的夜间模式,此时应考虑其对植物水分的影响。本研究强调了昼夜节律在调控林木水利用中的关键作用,并建议制定基于时间和环境稳定性的灌溉策略,以优化水分管理和应对气候变化。

关键词：环境稳定性昼夜差异树干液流叶片水分生理昼夜节律

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Quantifying the contribution of natural variability to September Arctic sea ice decline

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Acta Oceanologica Sinica 2016年第5期35卷 49-53页

作者： SONG Mirong WEI lixin wang Zhenzhan State Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences Key Laboratory of Research on Marine Hazards Forecasting National Marine Environmental Forecasting CenterState Oceanic Administration Key Laboratory of Microwave Remote Sensing National Space Science CenterChinese Academy of Sciences

Arctic sea ice extent has been declining in recent decades. There is ongoing debate on the contribution of natural internal variability to recent and future Arctic sea ice changes. In this study, we contrast the trends in the forced and unforced simulations of carefully selected global climate models with the extended observed Arctic sea ice records. The results suggest that the natural variability explains no more than 42.3% of the observed September sea ice extent trend during 35 a（1979–2013） satellite observations, which is comparable to the results of the observed sea ice record extended back to 1953（61 a, less than 48.5% natural variability）. This reinforces the evidence that anthropogenic forcing plays a substantial role in the observed decline of September Arctic sea ice in recent decades. The magnitude of both positive and negative trends induced by the natural variability in the unforced simulations is slightly enlarged in the context of increasing greenhouse gases in the 21st ***, the ratio between the realizations of positive and negative trends change has remained steady, which enforces the standpoint that external forcing will remain the principal determiner of the decreasing Arctic sea ice extent trend in the future.

关键词： internal variability sea ice decline external forcing

Plasma-induced chemical etching generating Ni_(3)S_(2) for formaldehyde detection

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chinese Chemical Letters 2022年第6期33卷 3035-3038页

作者： Jiaxin Zhou Li Zhao Qiang wang lixin Zuo Ana Zhao Huimin Yu Xue Jiang Xiaoli Xiong College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610068China

In this paper,Ni_(3)S_(2)nanosheet(NS)was generated by chemical etching with sodium sulfide directly on the nickel foam(NF),which was induced by dielectric barrier discharge plasma in *** with other chemical etching methods of nickel-based nanomaterials,this method was not only rapid(40 min)and mild(at room temperature and atmospheric pressure),but also showed consistent stability and good *** Ni_(3)S_(2)NS/NF electrode showed excellent performance in the electrochemical detection of formaldehyde under alkaline *** had a good linear relationship with the concentration of formaldehyde in the range of 0.002-5.45 mmol/L(R^(2)=0.9957)and the limit of detection(LOD)was 1.23μmol/L(S/N=3).The sensitivity was 1286.9μA L mmol^(–1)cm^(–2),and the response time was about 5 *** plasma-induced chemical etching strategy provides a simple and stable electrode preparation method,which has great application prospects in nonenzymatic electrochemical sensors.

关键词： Chemical etching Microplasma Electrochemical detection Formaldehyde

Sources of ambient non-methane hydrocarbon compounds and their impacts on O_(3) formation during autumn,beijing

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Journal of Environmental sciences 2022年第4期34卷 85-97页

作者： Fangjie Li Shengrui Tong Chenhui Jia Xinran Zhang Deng Lin wenqian Zhang Weiran Li Lili wang Maofa Ge lixin Xia College of Chemistry Liaoning UniversityShenyang 110036China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China Center for Excellence in Regional atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of chinese academy of sciences Beijing 100049China Key Laboratory of Oasis Ecology College of Resource and Environment SciencesXinjiang UniversityUrumqi 830046China State Key Laboratory of atmospheric Boundary Layer physics and atmospheric Chemistry(LAPC) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China Department of Chemical and Environmental Engineering Yingkou Institute of TechnologyYingkou 115014China

The field observation of 54 non-methane hydrocarbon compounds(NMHCs)was conducted from September 1 to October 20 in 2020 during autumn in Haidian District,*** mean concentration of total NMHCs was 29.81±11.39 ppbv during this period,and alkanes were the major *** were typical festival effects of NMHCs with lower concentration during the National *** and aromatics were the dominant groups in ozone formation potential(OFP)and OH radical loss rate(L_(OH)).The positive matrix factorization(PMF)running results revealed that vehicular exhaust became the biggest source in urban areas,followed by liquefied petroleum gas(LPG)usage,solvent usage,and fuel *** box model coupled with master chemical mechanism(MCM)was applied to study the impacts of different NMHCs sources on ozone(O_(3))formation in an O_(3)*** simulation results indicated that reducing NMHCs concentration could effectively suppress O_(3)***,reducing traffic-related emissions of NMHCs was an effective way to control O_(3)pollution at an urban site in beijing.

关键词： Non-methane hydrocarbon compounds Festival effects Ozone Source apportionment Master chemical mechanism

Evaluation of the carbon isotopic effects of NDIR and CRDS analyzers on atmospheric CO2 measurements

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Science china Earth sciences 2016年第6期59卷 1299-1307页

作者： XIA LingJun ZHOU LingXi Marcel V.van der SCHOOT Chris W.RELLA LIU lixin ZHANG Gen wang HongYang chinese academy of Meteorological sciences China Meteorological AdministrationBeijing 100081China Nanjing University of Information Science and Technology Nanjing 210044China Center for Australian Weather and Climate Research CSIRO Ocean and Atmosphere FlagshipAspendale 3195Australia Picarro Inc. Santa Clara 95054USA

Non-dispersive infrared （NDIR） and cavity ring-down spectroscopy （CRDS） CO2 analyzers use 12CO2 isotopologue absorption lines and are insensitive to all or part of other CO2-related isotopologues. This may produce biases in CO2 mole fraction measurements of a sample if its carbon isotopic composition deviates from that of the standard gases being used. To evaluate and compare the effects of carbon isotopic composition on NDIR and CRDS CO2 analyzers, we prepared three test sample air cylinders with varying carbon isotopic abundances and calibrated them against five standard cylinders with ambient carbon isotopic composition using CRDS and NDIR systems. We found that the CO2 mole fractions of the sample cylinders measured by G1301 （CRDS） were in good agreement with those measured by LoFlo （NDIR）. The CO2 values measured by both instruments were higher than that of a CO2 isotope measured by G2201i （CRDS） analyzer for a test cylinder with depleted carbon isotopic composition δ^13C =-36.828%0, whereas no obvious difference was found for other two test cylinders with 3 δ^13C=-8.630‰ and δ^13C=-15.380‰, respectively. According to the theoretical and experimental results, we concluded that the total CO2 mole fractions of samples with depleted isotopic compositions can be corrected on the basis of their 12CO2 values calibrated by standard gases using LoFlo and G1301 if the fi13C and fi180 values are known. Keywords NDIR and CRDS analyzers, Carbon isotopic effects, CO2 measurements

关键词： NDIR and CRDS analyzers Carbon isotopic effects CO2 measurements