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Comparison of Two Air Pollution Episodes over Northeast China in Winter 2016/17 Using Ground-Based Lidar

Journal of Meteorological Research 2018年第2期32卷 313-323页

作者： Yanjun MA Hujia ZHAO Yunsheng DONG Huizheng che Xiaoxiao LI Ye HONG Xiaolan LI Hongbin YANG Yuche LIU Yangfeng WANG ningwei LIU Cuiyan SUN Institute of Atmospheric Environment China Meteorological Administration Shenyang 110016 Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 State Key Laboratory of Severe Weather/Institute of Atmospheric Composition Chinese Academy of Meteorological Sciences Beijing 100081 Dalian Municipal Meteorological Observatory Dalian 116001 Jinan Center of Aviation Control Jinan 250107

This study analyzes and compares aerosol properties and meteorological conditions during two air pollution episodes in 19–22（E1） and 25–26（E2） December 2016 in Northeast China. The visibility, particulate matter（PM） mass concentration, and surface meteorological observations were examined, together with the planetary boundary layer（PBL） properties and vertical profiles of aerosol extinction coefficient and volume depolarization ratio that were measured by a ground-based lidar in Shenyang of Liaoning Province, China during December 2016–January *** suggest that the low PBL height led to poor pollution dilution in E1, while the high PBL accompanied by low visibility in E2 might have been due to cross-regional and vertical air transmission. The PM mass concentration decreased as the PBL height increased in E1 while these two variables were positively correlated in E2. The enhanced winds in E2 diffused the pollutants and contributed largely to the aerosol transport. Strong temperature inversion in E1 resulted in increased PM2.5 and PM10 concentrations, and the winds in E2 favoured the southwesterly transport of aerosols from the North China Plain into the region surrounding Shenyang. The large extinction coefficient was partially attributed to the local pollution under the low PBL with high ground-surface PM mass concentrations in E1,whereas the cross-regional transport of aerosols within a high PBL and the low PM mass concentration near the ground in E2 were associated with severe aerosol extinction at high altitudes. These results may facilitate better understanding of the vertical distribution of aerosol properties during winter pollution events in Northeast China.

关键词： aerosol pollution ground-based lidar Northeast China

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Atmospheric extinction properties in Shenyang,China

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Particuology 2015年第1期13卷 120-126页

作者： ningwei Liu Yanjun Ma Jianzhong Ma Yangfeng Wang Suying Yang Liguang Li Chinese Academy of Meteorological Sciences Nanjing University of Information Science & Technology Institute of Atmospheric Environment China Meteorological Administration

Atmospheric visibility impairment due to human activities is becoming increasingly significant in metropolitan 8henyang, China. In this study, hourly data of relevant factors throughout the year 2010 in Shenyang were used to evaluate the local atmospheric extinction properties. The results show that the average coefficient of total extinction and aerosol single-scattering albedo in 2010 were 622.72 Mm^-1 and 0.87, respectively, values that are characteristic of the ＂municipal pollution type＂. Visibility is most impaired during winter and especially in January. The coefficient of total extinction exhibits a single daily cycle with a maximum at 5-6 am and a minimum at 3 pm. The mean extinction contributions of the constituents, from high to low, were particle scattering （87.49%）, particle absorption, gas absorption, and gas scattering. The extinction contribution of gas molecules was little more than 4.5%, far smaller than that of particles. Scattering by particles was the main contributor to extinction, especially in the morning and around midnight.

关键词： Atmospheric visibility Extinction properties Extinction contributions Partide scattering

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MCRNet:Underwater image enhancement using multi-color space residual network

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Biomimetic Intelligence & Robotics 2024年第3期4卷 23-33页

作者： ningwei Qin Junjun Wu Xilin Liu Zeqin Lin Zhifeng Wang School of Mechatronic Engineering and Automation Foshan UniversityFoshan 528225China

The selective attenuation and scattering of light in underwater environments cause color distortion and contrast reduction in underwater images,which can impede the ever-growing demand for underwater robot *** address these issues,we propose a Multi-Color space Residual Network(MCRNet)for underwater image *** method takes advantage of the unique features of color representation in the RGB,HSV,and Lab color *** utilizing the distinct feature representations of images in different color spaces,we can highlight and fuse the most informative features of the three color *** approach employs a self-attention mechanism in the multi-color space feature fusion *** experiments demonstrate that our method achieves satisfactory results in color correction and contrast improvement of underwater images,particularly in severely degraded ***,our method outperforms state-of-the-art methods in both subjective visual comparison and objective evaluation metrics.

关键词： Underwater image enhancement Deep learning Color correction Underwater robots

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Studies on Tomato Seedling Quality Indices Under Simulated Shipping and Storage Conditions

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Agricultural Sciences in China 2004年第12期3卷 948-952页

作者： ningwei GEXiao-guang LITian-lai ShenyangAgriculturalUniversity Shenyang110161P.R.China

Indices of the tomato seedling quality maintenance level after production before field planting were studied through simulated experiments, small—scale operation, indoor analyses and measurements, and field observation. The results showed that under simulated shipping and storage conditions, seedling quality change following different durations (days) of shipping and storage was correlated significantly or even very significantly with certain physiological and morphological indices. With various measured indices following different periods of shipping and storage treatment subjected to multinomial successive regressive correlation analysis, the principal factors influencing seedling quality maintenance level are identified to be chlorophyll content →dry short weight → leaf freshness index in order of their importance. Significance analysis with multinomial fitted equation indicated that correlations between any one of above three factors and the growth index after field planting reached very significant difference level.

关键词： Tomato seedling Shipping and storage after production Physiological change Quality maintenance

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Multilevel air quality evolution in Shenyang:Impact of elevated point emission reduction

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Journal of Environmental Sciences 2022年第3期34卷 300-310页

作者： Xiaolan Li Guiqian Tang Liguang Li Weijun Quan Yangfeng Wang Ziqi Zhao ningwei Liu Ye Hong Yanjun Ma Institute of Atmospheric Environment China Meteorological AdministrationNo.388 Changbai South RoadShenyangLiaoning 110166China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Environmental Meteorology Forecast Center of Beijing-Tianjin-Hebei Beijing 100089China

Visibility observed at different altitudes is favorable to understand the causes of air *** conducted 4-years of observations of visibility at 2.8 and 60 m and particulate matter(PM)concentrations from 2015 to 2018 in Shenyang,a provincial city in Northeast *** results indicated that visibility increased with the increasing height in winter(especially at night),and decreased with height in summer(especially at the daytime).PM concentration exhibited opposite vertical variation to visibility,reflecting that visibility de-grades with the increase of aerosol concentration in the *** radiosonde meteorological data showed that weak turbulence in the planetary boundary layer(PBL)in winter favored aerosols'accumulation near the *** in summer,unstable atmospheric con-ditions,upper-level moister environment,and regional transport of air pollutants resulted in the deterioration of upper-level ***-annual variation in the two-level visibility indicated that the upper-level visibility improved more significantly than low-level visibil-ity,much likely due to the reduction in emission of elevated point sources in *** study suggested that strengthening the control of surface non-point emissions is a promis-ing control strategy to improve Shenyang air quality.

关键词： Aerosol pollution Atmospheric visibility Planetary boundary layer Northeast China Vertical evolution

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Ideotype root architecture for efficient nitrogen acquisition by maize in intensive cropping systems

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Science China(Life Sciences) 2010年第12期53卷 1369-1373页

作者： MI GuoHua cheN FanJun WU QiuPing LAI ningwei YUAN LiXing ZHANG FuSuo Key Laboratory of Plant Nutrition MOAKey Laboratory of Plant-Soil InteractionMOECollege of Resources and Environmental ScienceChina Agricultural UniversityBeijing 100193China

The use of nitrogen(N) fertilizers has contributed to the production of a food supply sufficient for both animals and humans despite some negative environmental *** food production by increasing N use efficiency in intensive cropping systems has become a major concern for scientists,environmental groups,and agricultural policymakers *** high-yielding maize systems the major method of N loss is nitrate *** this review paper,the characteristic of nitrate movement in the soil,N uptake by maize as well as the regulation of root growth by soil N availability are *** suggest that an ideotype root architecture for efficient N acquisition in maize should include(i) deeper roots with high activity that are able to uptake nitrate before it moves downward into deep soil;(ii) vigorous lateral root growth under high N input conditions so as to increase spatial N availability in the soil;and(iii) strong response of lateral root growth to localized nitrogen supply so as to utilize unevenly distributed nitrate especially under limited N conditions.

关键词： maize nitrogen use efficiency root architecture nitrate rhizosphere

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Variations in Column Concentration of Greenhouse Gases in China and Their Response to the 2015-2016 El Niño Event

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Journal of Meteorological Research 2024年第3期38卷 608-619页

作者： ningwei LIU Lingjun XIA Youjun DOU Shaorou DONG Jing WEN Ying WANG Rui FENG Ruonan WANG Yuhe LI Institute of Atmospheric Environment China Meteorological AdministrationShenyang110166China Jiangxi Ecological Meteorology Centre Nanchang330096China Beijing Xiangyuan Academy of Meteorological Observing Technology Beijing100081China Climate Centre of Guangdong Province Guangzhou510641China Guangdong Meteorological Service Guangzhou510062China Liaoning Provincial Meteorological Equipment Support Centre Shenyang110166China Meteorological Centre of Northeast Air Traffic Administration of Civil Aviation of China Shenyang110161China

Since the industrial revolution,enhancement of atmospheric greenhouse gas concentrations as a result of human activities has been the primary cause of global *** monitoring and evaluation of greenhouse gases are significant prerequisites for carbon emission *** monthly data of global atmospheric carbon dioxide(CO_(2))and methane(CH4)column concentrations(hereinafter XCO_(2) and XCH_(4),respectively)retrieved by the Greenhouse Gas Observation Satellite(GOSAT),we analyzed the variations in XCO_(2)and XCH_(4)in China during 2010-2022 after confirming the reliability of the ***,the influence of a strong El Niño event in 2015-2016 on XCO_(2) and XCH_(4) variations in China was further *** results show that the retrieved XCO_(2) and XCH_(4) from GOSAT have similar temporal variation trends and significant correlations with the ground observation and emission inventory data of an atmospheric background station,which could be used to assess the variations in XCO_(2) and XCH_(4) in ***_(2) is high in spring and winter while XCH_(4) is high in *** XCO_(2) and XCH_(4) gradually declined from Southeast China to Northwest and Northeast China,with variation ranges of 401-406 and 1.81-1.88 ppmv,respectively;and the high value areas are located in the middle-lower Yangtze River ***_(2) and XCH_(4) in China increased as a whole during 2010-2022,with rapid enhancement and high levels of XCO_(2) and XCH_(4) in several *** significant increases in XCO_(2) and XCH_(4) over China in 2016 might be closely related to the strong El Niño-Southern Oscillation(ENSO)event during *** a global warming background in 2015,XCO_(2) and XCH_(4) increased by 0.768%and 0.657%in 2016 in *** analysis reveals that both the XCO_(2) and XCH_(4) variations might reflect the significant impact of the ENSO event on glacier melting in the Tibetan Plateau.

关键词： greenhouse gases column concentration CO_(2) CH4 El Niño-Southern Oscillation(ENSO) El Niño

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METHOD FOR ALONG-TRACK DUAL-ANTENNA AIRBORNE RADAR'S GMTI WHEN THE ATENNA ERROR CHANGES PULSE TO PULSE

引用

Journal of Electronics(China) 2005年第3期22卷 248-254页

作者： ningwei LiaoGuisheng KeyLaboratoryforRadarSignalProcessing XidianUniversityXi＇an710071China

This paper presents a joint method of Doppler Beam Sharpen (DBS) imaging and Signal Subspace Processing (SSP) to achieve Ground Moving Target Indication(GMTI) for along- track dual-antenna airborne radar. When the error of the two antennas (also refers to channels) changes pulse to pulse, the method SSP is used to precisely calibrate the two antennas’ DBS images, then to detect the ground moving targets in the difference image of the two calibrated images. The method DBS-SSP is proved to offer performance improvement on the actually measured data and simulated data.

关键词： Airborne radar Channel error Moving Target Indication (MTI) Signal Subspace Processing (SSP)

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Optimization Design of the Intake System Based on an Engine for FSC

Optimization Design of the Intake System Based on an Engine ...

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2020中国汽车工程学会年会暨展览会

作者： chen Liuyang Guo Yuyang Jin ningwei School of Automotive Studies Tongji University

The full name of FSC is Formula Student *** are required to design,process and assemble a racing car within one *** to the competition rules,the engine displacement used should not be more than 710 mL,and a limiter with a diameter of no more than 20 mm should be set at the intake pipe,which makes the original engine characteristics different from the commonly used racing *** design of the intake system will directly affect the dynamic performance of the *** main content of this paper is to optimize the intake design of a 675 mL engine used for FSAE *** using CATIA modeling and AVL BOOST onedimensional simulation,the influence of intake manifold and other dimensions on the engine characteristics is analyzed,and we design the intake dimensions for FSC racing *** the boost simulation,3.5 L volume is selected as the final volume of the plenum after considering the layout *** this basis,the shape of the plenum is modeled and 3 D simulated,and the scheme with better outlet mass flow rate and the uniformity of each cylinder is selected as the final *** considering the layout space,through the simulation of intake manifold length in 90 ～230 mm,it is found that with the increase of manifold length,the peak value of engine torque gradually moves to low engine *** the commonly used engine speed of FSC racing car is about 7000 r/min,170 mm is selected as the manifold length *** the simulation of manifold diameter,it is found that in the range of 32～42 mm,with the increase of manifold diameter,the peak value of engine torque gradually moves to high engine speed,and finally the manifold diameter is determined as 34 mm.

关键词： Formula SAE AVL BOOST intake system and exhaust system 1D design intake system 3D design

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Simultaneous separation and identification of four steroids by capillary HPLC-ESI-MS with column switch technology

Simultaneous separation and identification of four steroids ...

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西北地区第七届色谱学术报告会甘肃省第十二届色谱年会

作者： Yuming Dong ningwei Lu Qiong an Ning Li School of Pharmacy Lanzhou University

A novel capillary-HPLC-ESI-MS method with column switch technology was established to separate and identify 18α-glycyrrhetinic acid,lupeol,pregnenolone and progesterone for the first time. The four steroids could be separated with a C18 column and gradient elute within 30 min and detected by UV at 214 *** and progesterone interconvert in acid solution through adding *** could not be separated and detected by UV at ***,they could be separated completely by ESI-MS when MS was used as capillary HPLC *** column switch column technology was used to preconcentrate the *** peaks were sharp and symmetry. This method can be used to investigate these steroids in biological samples,natural plant,fluids and food.

关键词： steroids capillary HPLC-ESI-MS column switch

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