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Research in Cold and Arid Regions 2011年第5期3卷 436-440页

作者： MingJin Zhan JunYing Sun JianMin Yin Jiangxi Climate Center Nanchang 330046 China Center for Atmosphere Watch and Service Beijing 10081 China

particle size distribution of 12-500 nm was measured at Mt. Waliguan, China Global Atmosphere Watch Baseline Observatory, from Aug. in 2005 to May in 2007.72-hr back-trajectories at 100-m arrival height above ground level for the same period were calculated at 6：00, 12：00, and 21：00 （Beijing Time） for each day using the Hybrid Single-particle Lagrangian Integrated Trajectory （HYSPLIT-4） model developed by NOAA/ARL. It was found that air mass sources significantly impact particle number concentration and size distribution at Mt. Waliguan. Cluster analysis of back-trajectories show that higher Aitken mode particle number concentration was observed when air masses came from or passed by the northeastern section of Mt. Waliguan, with short trajectory length. High number concentration of nucleation mode was associated with air masses from clean regions, with long trajectory length.

关键词： particle number concentration particle size distribution back-trajectories cluster analysis Mt. Waliguan

RELATIVE LEVELS OF INDOOR AND OUTDOOR particle number concentrationS IN A RESIDENTIAL BUILDING IN XI'AN

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China Particuology 2006年第6期4卷 342-345页

作者： Yanming Kang Ke Zhong Shun-Cheng Lee School of Environmental Science and Engineering Donghua University Shanghai 201620 China Research Center of Urban Environmental Technology and Management Department of Civil and Structural Engineering Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong China

The time series of indoor and outdoor particle number concentrations in a naturally ventilated residential building in Xi＇an were tested simultaneously for 7 days in summer. The relationships between indoor and outdoor concentrations were examined and discussed, and linear regression analysis was employed to correlate the indoor and outdoor concentrations. The diurnal cycles of indoor and outdoor particle concentrations of different particle size ranges all showed positive correlations between indoor and outdoor number concentrations, The I/O ratios of number concentrations varied with the increase of particle size in the range of 0.89 （±0.19） to 0.99 （±0.15）.

关键词： indoor and outdoor particle number concentration I/O ratio linear regression analysis

Application of nanoparticle tracking analysis for characterising the fate of engineered nanoparticles in sediment-water systems

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Journal of Environmental Sciences 2018年第2期30卷 62-71页

作者： Ping Luo Alejandro Roca Karen Tiede Katie Privett Jiachao Jiang John Pinkstone Guibin Ma Jonathan Veinot Alisatair Boxall School of Environment Science and Spatial informatics Chinese University of Mining and Technology Department of Physics University of York Centre for Chemical Safety and Stewardship (CCSS) Food and Environment Research Agency (FERA) Environment Department University of York Department of Chemistry University of Alberta

Novel applications of nanotechnology may lead to the release of engineered nanoparticles（ENPs）, which result in concerns over their potential environmental hazardous impact. It is essential for the research workers to be able to quantitatively characterise ENPs in the environment and subsequently to assist the risk assessment of the ENPs. This study hence explored the application of nanoparticle tracking system（NTA） to quantitatively describe the behaviour of the ENPs in natural sediment-water systems. The NTA allows the measurement of both particle number concentration（PNC） and particle size distribution（PSD） of the ENPs. The developed NTA method was applied to a range of gold and magnetite ENPs with a selection of surface properties. The results showed that the positively-charged ENPs interacted more strongly with the sediment than neutral and negatively-charged ENPs. It was also found that the citrate coated Au ENPs had a higher distribution percentage（53%） than 11-mercaptoundecanoic acid coated Au ENPs（20%） and citrate coated magnetite ENPs（21%）. The principles of the electrostatic interactions between hard（and soft） acids and bases（HSAB） are used to explain such behaviours; the hard base coating（i.e. citrate ions） will interact more strongly with hard acid（i.e. magnetite） than soft acid（i.e. gold）.The results indicate that NTA is a complementary method to existing approaches to characterise the fate and behaviour of ENPs in natural sediment.

关键词： Quantitative characterisation Hard and soft acids and bases Fate of engineered nanoparticles Nanoparticle tracking system particle number concentration particle size distribution

Investigation on the particle loss and applicability of aviation nvPM measurement methodology for wide particle size ranges

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Particuology 2024年第12期95卷 154-165页

作者： Minghua Wang Liuyong Chang Xuehuan Hu Meiyin Zhu Bin Zhang Guangze Li Zheng Xu Hangzhou International Innovation Institute Beihang UniversityHangzhou311115China School of Energy and Power Engineering Beihang UniversityBeijing100083China

The precise measurement of non-volatile Particulate Matter(nvPM)is outlined in aviation engine emissions regulations by the International Civil Aviation Organization(ICAO).However,assessing particle losses in the sampling and transfer unit presents challenges,raising concerns about the system's ***,nvPM emissions from small and medium aircraft engines,with thrust not exceeding 26.7 kN,vary widely in size,adding complexity to the measurement *** provide a comprehensive analysis of particle losses in the sampling and transfer subsystems,this study established a test bench equipped with a nanoparticle *** generator simulates nvPM emissions from medium and small aircraft engines and can consistently produce nvPMs with a wide range of concentrations(103–107/cm^(3))and size distributions(20–160 nm).Thermophoretic loss verification experiments were conducted within the sampling pipeline under significant temperature differences,investigating the effects of particle size,temperature gradient,and airflow rate on thermophoretic particle *** experimental results demonstrated good agreement with the predictions of the model proposed by United Technologies Research Centre(UTRC).After correcting for temperature,the experimental data showed a maximum disparity of 2%under typical engine exhaust conditions,validating the predictability of the thermophoretic loss model for various engine ***,verification experiments for particle diffusion and bending losses were *** analysis with the UTRC model revealed nvPM inertial deposition under laminar flow conditions with low Reynolds numbers(Re).As the Re increased,the measured data more closely aligned with the *** losses due to secondary flow patterns ranged from 1%to 10%,depending on particle size and flow *** finding supports the applicability of aviation nvPM measurement methods across a wide particle size *** research provides theoretic

关键词： Non-volatile particulate matter Thermophoretic loss Transfer loss particle number concentration particle size distribution

Relative Levels of Indoor and Outdoor particle number concentrations in a Residential Building in Xi’an

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Relative Levels of Indoor and Outdoor Particle Number Concen...

Evaluating the performance of a WRF microphysics ensemble through comparisons with aircraft observations

中国颗粒学会2006年年会暨海峡两岸颗粒技术研讨会

作者： Yan-ming Kang, Ke Zhong, Shun-cheng Lee (School of Environmental Science and Engineering, Donghua University, Shanghai 201620, China Research Centre for Environmental Technology and Management, Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hom Hung, Kowloon, Hong Kong, China)

＜正＞The time series of indoor and outdoor particle number concentrations in a natural ventilating residential building were tested simultaneously for 7 d in Xi’an in summer. The relationships between indoor and outdoor concentrations were examined and discussed, and linear regression analysis was employed to correlate the indoor concentration levels with outdoor concentrations. The diurnal cycles of indoor and outdoor particle concentrations of different size ranges all showed positive correlations between indoor and outdoor number concentrations. The I/O ratios of number concentrations varied with the increase of particle size, the range of the I/O ratios was from 0.89 （±0.19） to 0.99 （±0.15）.

关键词： indoor and outdoor particle number concentration I/O ratio linear regression analysis

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Atmospheric and Oceanic Science Letters 2021年第4期14卷 1-6页

作者： Yuan Fu Hengchi Lei Jie-fan Yang Zhibo Gao Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijingChina

observation data obtained in a mesoscale convective system are compared to Weather Research and Forecasting(WRF)model simulations using four microphysics schemes(Morrison,WSM6,P3,SBM)with different *** main purpose of this paper is to assess the performance of the microphysics ensemble in terms of cloud microphysical *** show that although the vertical distributions of liquid water content(LWC)and ice water content(IWC)simulated by the four members are quite different in the convective cloud region,they are relatively uniform in the stratiform cloud ***,the results of the Morrison scheme are very similar to the ensemble average,and both of them are closer to the observations compared to the other ***,the authors also note that all members still overpredict the LWC by a factor of 2–8 in some regions,resulting in large deviation between the observation and ensemble average.

关键词： Aircraft observation Microphysics ensemble particle number concentration Liquid/ice water content

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Comparison of aircraft observations with ensemble forecast model results in terms of the microphysical characteristics of stratiform precipitation

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Atmospheric and Oceanic Science Letters 2020年第5期13卷 452-461页

作者： FU Yuan LEI Hengchi YANG Jiefan GUO Jiaxu ZHU Jiangshan Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary Science University of Chinese Academy of SciencesBeijingChina

The prediction of the particle number concentration and liquid/ice water content of cloud is significant for many aspects of atmospheric ***,given the uncertainties in the initial and boundary conditions and imperfections of microphysical schemes,the accurate prediction of these microphysical properties of cloud is still a big *** ensemble approach may be a viable way to reduce forecast *** this paper,a large-scale stratiform cloud precipitation process is studied by comparing results of a 10-member ensemble forecast model with aircraft observation *** means of the ensemble average,the prediction of bulk parameters such as liquid water content and ice water content can be improved in comparison with the control member,but the particle number concentrations are still one to two orders of magnitude less than those from *** of raindrop size spectra reveals a big distinction between observations and predictions for particles with a diameter less than 1000μm.

关键词： Aircraft observation ensemble forecast model particle number concentration liquid/ice water content