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Effects of climate changes on dust aerosol over East Asia from RegCM3

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Advances in Climate Change Research 2016年第3期7卷 145-153页

作者： ZHANG Dong-Feng GAO Xue-Jie Ashraf ZAKEY Filippo GIORGI Shanxi Climate Center Taiyuan 030006China Climate Change Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Egyptian Meteorological Authority Cairo 11784Egypt The Abdus Salam International Centre for Theoretical Physics Trieste 34100Italy

In order to understand impacts of global warming on dust aerosol over East Asia, a regional climate model(RegCM3) coupled with a dust model is employed to simulate the present(1991-2000, following the observed concentration of the greenhouse gases) and future(2091-2100,following the A1B scenario) dust aerosol. Three experiments are performed over East Asia at a horizontal resolution of 50 km, driven by the outputs from a global model of the Model for Interdisciplinary Research on Climate(MIROC3.2_hires), two without(Exp.1 for the present and Exp.2 for the future) and one with(Exp.3 for the future) the radiative effects of dust aerosols. Effects of climate changes on dust aerosols and the feedback of radiative effects in the future are investigated by comparing differences of Exp.2 and Exp.1, Exp.3 and Exp.2, respectively. Results show that global warming will lead to the increases of dust emissions and column burden by 2% and 14% over East Asia, characterized by the increase in December-January-February-March(DJFM) and the decrease in Aprile May(AM). Similar variations are also seen in the projected frequencies of high dust emission events, showing an advanced active season of dust in the future. The net top-of-atmosphere(TOA)radiative forcing is positive over the desert source regions and negative over downwind regions, while the surface radiative forcing is negative over the domain, which will lead to a reduction of dust emissions and column burden.

关键词： Dust aerosol Climate changes RegCM3 Numerical simulations

Characteristics of aerosol Activation Efficiency and aerosol and CCN Vertical Distributions in North China

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Acta meteorologica Sinica 2012年第5期26卷 579-596页

作者：段婧陈勇郭学良 Chinese Academy of Meteorological Sciences State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences

By analyzing airborne observations over North China from 30 flights during spring and autumn of 2005-2007, characteristics of the vertical distributions of aerosol and cloud condensation nuclei （CCN） at 0.3% supersaturation in various locations of North China are investigated. The measurement samplings were conducted over different surfaces such as plains, plateau, and sea. The results show that the number concentration of accumulation mode aerosols was greater in autumn than in spring, but the reverse is true for CCN. This means that more aerosols with diameters smaller than 100 nm could be activated as CCN in spring, and this could induce higher aerosol activation efficiency. The aerosol activation efficiency over the plains near the Taihang Mountain was greater in spring than in autumn, and it was greater over sea than over land. The aerosol activation efficiency above the boundary layer over the Bashang Plateau was very low. Based on a fit of the negative exponential vertical distributions of aerosol and CCN, a spatial parameterization model of aerosol and CCN as well as aerosol activation efficiency over North China was proposed. The results show that aerosol activation efficiency was not clearly dependent on altitude because it was mainly affected by regional physical and chemical characteristics of aerosols and the ambient atmospheric conditions. The mean aerosol activation efficiency is 0.66, with values of 0.70 and 0.53 in spring and autumn, respectively.

关键词： aerosol cloud condensation nuclei vertical distribution activation efficiency spatial paramete-rization model

Climatic Trend of Cloud Amount Related to the aerosol Characteristics in Beijing During 1950-2005

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Acta meteorologica Sinica 2010年第6期24卷 762-775页

作者：王继志杨元琴张光智于淑秋 Centre for Atmosphere Watch and Services Chinese Academy of Meteorological Sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

This paper analyzes the correlation between variations of total and low cloud amounts and the varying features of aerosols related to urban development of Beijing by using the cubic spline fitting method based on the monthly meteorological data of temperature,humidity,precipitation,clouds,and aerosol optical depth （AOD） during 1950-2005.The statistics on the development of the city of Beijing in this period,including the total industrial output,population,residential housing development,highway construction,charcoal production,etc.,is revealed.Accompanying the rapid urban development of Beijing over the past 55 years or so,the urban aerosol concentration and composition have changed.The results indicate that：1） there is a general trend of climate warming and drying in Beijing;2） the total cloud amount in all seasons declines drastically,but lower cloud amount climbs up slightly;3） the high correlations between cloud amount and the indices of Beijing urban development such as the housing area,charcoal production,and road construction show that the variation of cloud amount is closely related to the urban development;4） the changing trend of AOD coincides more closely with the variation of low cloud amount.The evident drop of total cloud amount is in agreement with the trend of climate warming and drying,while the slight growth of low cloud amount is likely caused by more haze and fog occurrences in the lower troposphere in association with the pollution responsible for the＂darkening＂of Beijing and the surrounding areas.

关键词： cloud variation aerosol aerosol optical depth（AOD） urban development climate trend

Size distribution of sulfur species in fine and ultrafine aerosol particles using sulfur K-edge XANES

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Chinese Physics C 2009年第11期33卷 965-968页

作者：林俊包良满刘卫李燕李玉兰马陈燕赵屹东 Shanghai Institute of Applied Physics Chinese Academy of Sciences Institute of High Energy Physics Chinese Academy of Sciences

The sulfur species existing in different size aerosol particles were determined based on the ＇white line＇ energy shift and the features of post edge structure of sulfur K-edge XANES （X-ray Absorption Near Edge Structure）. The results indicated that sulfates were dominant sulfur species in aerosol particles. However, small amount of reductive sulfur species were also found in the ultrafine aerosol particles（〈0.1 μm）. Sulfates in aerosols mostly exhibited as （NH4）2SO4 and gypsum. than 0.952 μm, while gypsum was the dominant sulfate Most （NH4）2SO4 distributed in aerosol particles finer in coarse aerosols.

关键词： sulfur species aerosol size distribution XANES

aerosol containment by airflow in biosafety laboratories

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Journal of Biosafety and Biosecurity 2019年第1期1卷 63-67页

作者： Xin Feng Yanguo Zhang Zhonglin Xu Donglin Song Guoqing Cao Lei Liang China Academy of Building Research Co. Ltd.30 North 3rd Ring East Rd.Beijing 100013China Wuhan Institute of Virology China Academy of Science44 Xiao Hong Shan Middle DistrictWu Han 430071China

In this paper,the progress and research related to aerosol containment by airflow in containment environments,e.g.,biosafety laboratories,are introduced from a mechanical engineering view.A good airdistribution strategy in the room,a reasonable and stable pressure gradient in the containment area,and a necessary buffer room comprise the integral parts for regulating the air flow and providing the necessary containment.An optimal air-distribution strategy would reduce the residence time of the bioaerosol in the lab room and lower the exposure risk of the work staff.The pressure difference between adjacent rooms provides sufficient isolation protection when the door is closed.Nevertheless,an unfavorable air exchange would occur when the door is open,owing to door movement,passing people,or a tiny temperature difference.A buffer room is therefore necessary to offset the negative impact and maintain the containment effect.

关键词： aerosol Containment Biosafety

Present status of aerosol research in China

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Journal of Environmental Sciences 1998年第4期10卷 108-113页

作者： Liu Yi Wang Ming-xing LAPC Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

１ＩｎｔｒｏｄｕｃｔｉｏｎＡｅｒｏｓｏｌｓｐｌａｙａｎｉｍｐｏｒｔａｎｔｒｏｌｅｉｎｃｌｉｍａｔｅｃｈａｎｇｅ，ａｉｒｑｕａｌｉｔｙ，ａｃｉｄｄｅｐｏｓｉｔｉｏｎ，ｖｉｓｉｂｉｌｉｔｙｒｅｄｕｃｔｉｏｎ，ａｎｄｃｌｏ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＡｅｒｏｓｏｌｓｐｌａｙａｎｉｍｐｏｒｔａｎｔｒｏｌｅｉｎｃｌｉｍａｔｅｃｈａｎｇｅ，ａｉｒｑｕａｌｉｔｙ，ａｃｉｄｄｅｐｏｓｉｔｉｏｎ，ｖｉｓｉｂｉｌｉｔｙｒｅｄｕｃｔｉｏｎ，ａｎｄｃｌｏｕｄｐｒｏｃｅｓｅｓ．Ｔｈｅｙａｒ...

关键词： aerosol biogeochemical cycle China.

3D Nanoprinting with Charged aerosol Particles-An Overview

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Accounts of Materials Research 2021年第11期2卷 1117-1128页

作者： Wooik Jung Peter V.Pikhitsa Yoon-Ho Jung Jooyeon Shin Minsung Han Mansoo Choi Global Frontier Center for Multiscale Energy Systems Seoul National UniversitySeoul 08826Korea Department of Mechanical Engineering Seoul National UniversitySeoul 08826Korea

CONSPECTUS:Three-dimensional(3D)printing is a revolutionary technology allowing rapid,cost-effectively,and flexible design of desired 3D products.In this regard,various techniques for downscaling 3D printing have been developed based on several methodologies in the past decades to exploit the advantages of 3D printing at the micro/nanoscale.The development of 3D nanoprinting techniques has provided a method to design unique and sophisticated nanoscale 3D objects enabling functional applications that are thus far constrained with conventional planar nanomanufacturing processes such as photolithography and electron beam lithography.However,the versatile and practical realization of 3D nanoprinting in a broad science and engineering field remains challenging due to limitations such as feature size resolution,suitable materials,and design flexibility.Therefore,innovative 3D nanoprinting techniques are required to overcome current limitations.In this Account,we describe our achievements in developing 3D nanoprinting with charged aerosols relying on the physics behind counteracting electric fields.We introduce the generation of charged aerosols,the most feasible in the broad range of fundamental building blocks(mainly all types of metals and alloys,their oxides,polymers,and organics)for 3D nanoprinting.Moreover,charged aerosols can be processed at ambient conditions easily.The aerosols could be precisely controlled and delivered for the assembly,using electric fields of complicated configurations despite the Brownian diffusion and other chaotic processes.The converging electric fields are formed around openings by the interactions of two electric fields.One of the electric fields comes from a negatively biased substrate.In contrast,the counteracting electric field comes from the positive ions distributed on a prepatterned dielectric layer over the substrate.As a result,the positively charged aerosols are focused through these fields to grow with nanoscale resolution only in the openings of the layer.Furthermore,a growi

关键词： printing aerosol lifting

PHYSICOCHEMICAL PROPERTIES OF SEA SURFACE LAYER aerosol OVER THE WESTERN PACIFIC

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Chinese Science Bulletin 1989年第16期34卷 1370-1374页

作者：杨绍晋陈冰如杨亦男钱琴芳周明煜郑月明余鸿健苏立荣 Institute of High Energy Physics Academia Sinica Beijing National Research Center for Marine Environment Forecasts Beijing

This report uses information obtained from the first cruise operated by the Sino-American cooperative sea-air interaction program in December 12, 1985—February 21, 1986 to discuss the physicochemical properties of ma... 详细信息

关键词： aerosol neutron activation analysis enrichment factor

The Efficacy of Plant-Based Ionizers in Removing aerosol for COVID-19 Mitigation

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Research 2021年第1期2021卷 70-80页

作者： Ady Suwardi Chin Chun Ooi Dan Daniel Chee Kiang Ivan Tan Hongying Li Ou Yang Zhong Liang Yuanting Karen Tang Jing Yee Chee Anton Sadovoy Shu-Ye Jiang Srinivasan Ramachandran Enyi Ye Chang Wei Kang Wun Chet Davy Cheong Keng Hui Lim Xian Jun Loh Institute of Materials Research and Engineering 2 Fusionopolis WayAgency for ScienceTechnology and ResearchSingapore 138634 Institute of High Performance Computing 1 Fusionopolis WayAgency for ScienceTechnology and ResearchSingapore 138632 Temasek Life Sciences Laboratory 1 Research LinkNational University of SingaporeSingapore 117604

Small-sized droplets/aerosol transmission is one of the factors responsible for the spread of COVID-19,in addition to large droplets and surface contamination(fomites).While large droplets and surface contamination can be relatively easier to deal with(i.e.,using mask and proper hygiene measures),aerosol presents a different challenge due to their ability to remain airborne for a long time.This calls for mitigation solutions that can rapidly eliminate the airborne aerosol.Pre-COVID-19,air ionizers have been touted as effective tools to eliminate small particulates.In this work,we sought to evaluate the efficacy of a novel plant-based ionizer in eliminating aerosol.It was found that factors such as the ion concentration,humidity,and ventilation can drastically affect the efficacy of aerosol removal.The aerosol removal rate was quantified in terms of ACH(air changes per hour)and CADR-(clean air delivery rate-)equivalent unit,with ACH as high as 12 and CADR as high as 141 ft^(3)/minute being achieved by a plant-based ionizer in a small isolated room.This work provides an important and timely guidance on the effective deployment of ionizers in minimizing the risk of COVID-19 spread via airborne aerosol,especially in a poorly-ventilated environment.

关键词： aerosol eliminate sized