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1Black carbon aerosols and their radiative properties in the Pearl River Delta region显示文摘The climatic and environmental effects of atmospheric aerosols are a hot topic in global science community, and radiative properties of the aerosols are one of the important parameters in assessing climatic change. Here we studied the black carbon concentration and absorption coefficient measured with aethalometers, scattering coefficient measured with nephelometers, and single scattering albedo derived at an atmospheric composition watch station in Guangzhou from 2004 to 2007. Our main results are as follows. The data of black carbon concentration and absorption coefficients measured with instruments cannot be directly used until they are measured in parallel with internationally accepted instruments for comparison, calibration, and reduction. After evaluation of the data, the result shows that the monthly mean of BC concentration varies 3.1―14.8 μg·m-3 and the concentration decreases by about 1 μg·m-3 in average over the four years; It is higher in the dry season with a multi-year mean of 8.9 μg/m3 and lower in the rainy season with a multi-year mean of 8.0 μg·m-3; The extreme maximum of monthly mean concentration occurred in December 2004 and extreme minimum in July 2007, and a 4-year mean is 8.4 μg·m-3. It is also shown that monthly mean scattering coefficient derived varies 129 -565 Mm-1, monthly mean absorption coefficient 32-139 Mm-1, and monthly mean single scattering albedo 0.71-0.91, with annual mean values of 0.80, 0.82, 0.79 and 0.84 for 2004, 2005, 2006 and 2007, respectively. Three instruments were used to take simultaneous measurements of BC in PM10, PM2.5, and PM1 and the results showed that PM2.5 took up about 90% of PM10 and PM1 accounted for about 68% of PM2.5, and BC aerosols are mainly present in fine particulates. The variability of BC concentrations is quite consistent between the Nancun station (141 m above sea level) and the Panyu station (13 m above sea level), which are 8 km apart from each other. The concentration in higher altitude station (Panyu) is consistently lower than the lower altitude station (Nancun), and the difference of annual mean is about 4 μg·m-3.WU Dui MAO JieTai DENG XueJiao TIE XueXi ZHANG YuanHang ZENG LiMin LI Fei TAN HaoBo BI XueYan HUANG XiaoYing CHEN Jing DENG Tao 2009Science China Earth Sciences2009,52,8:58
2The compositions,sources,and size distribution of the dust storm from China in spring of 2000 and its impact on the global environment显示文摘The average mass concentration of the aerosols in Beijing during the dust storm in the spring of 2000 was -6000 μg · m-3, -30 times as high as that in the non-dust storm days. The enrichment factors of the pollution elements As, Sb and Se were higher than those in the non-dust storm days. This indicated that As, Sb and Se resulted from the pollution sources of those areas, through which the dust storm passed during their long-range transport, in addition to the local pollution sources in Beijing. The enrichment factors of the Pb, Zn, Cd and Cu were much less than those in the non-dust storm days, suggesting that the local pollution sources in Beijing area contributed to them mostly. The enrichment factors of elements Al, Fe, Sc, Mn, Na, Ni, Cr, V and Co were close to 1, showing that these elements originated from crust. The concentration of S in the dust storm was -10 μg · m-3,4 times as high as that in non-dust storm. S in the aerosols resulted from the adsorption of gaseous SO2 and the consequentGuoshun Zhuang Jinghua Guo Hui Yuan Chengyi Zhao 2001Chinese Science Bulletin2001,46,11:44
3Characteristics of size distributions and sources of water-soluble ions in Lhasa during monsoon and non-monsoon seasons显示文摘To understand the physical and chemical characteristics, particle size distribution and sources of size-separated aerosols in Lhasa, which is located on the Tibetan Plateau(TP), six sizes of aerosol samples were collected in Lhasa in 2014. Ca^(2+), NH_4^+, NO_3^-,SO_4^(2-)and Cl-were the dominant ions. The ratio of cation equivalents(CE) to anion equivalents(AE) for each particle size segment indicated that the atmospheric aerosols in Lhasa were alkaline. SO_4^(2-)and NO_3^-could be neutralized by Ca^(2+), but could not be neutralized by NH_4^+, according to the [NH_4^+]/[NO_3^-+ SO_4^(2-)] and [Ca^(2+)]/[NO_3^-+ SO_4^(2-)] ratios. Mobile sources were dominant in PM_(0.95-1.5),PM_(1.5-3) and PM_(3-7.2), while stationary sources were dominant in the other three size fractions according to the [NO_3^-]/[SO_4^(2-)] ratios. The particle size distribution of all watersoluble ions during monsoon and non-monsoon periods was characterized by a bimodal distribution due to the different sources and formation mechanisms, and it was revealed that different ions had different sources in different seasons and different particle size segments by combining particle size distribution with correlation analysis. Source analysis of aerosols in Lhasa was performed using the Principal component analysis(PCA) for the first time, which revealed that combustion sources, motor vehicle exhaust, photochemical reaction sources and various types of dust were the main sources of Lhasa aerosols.Furthermore, Lhasa's air quality was also affected by long-distance transmission, expressed as pollutants from South Asia and West Asia, which were transmitted to Lhasa according to backward trajectory analysis.Nannan Wei Zhiyou Xu Junwen Liu Guanghua Wang Wei Liu Deqing Zhuoga Detao Xiao Jian Yao 2019Journal of Environmental Sciences2019,31,8:7
4Secondary organic aerosols in Jinan, an urban site in North China: Significant anthropogenic contributions to heavy pollution显示文摘Secondary organic aerosols(SOAs) are an important component of particulates, but whether biogenic SOAs(BSOAs) or anthropogenic SOAs(ASOAs) are the dominant contributors to haze pollution remains poorly characterized. In this study, particulate samples were collected from September 2014 to August 2015 at an urban site in Jinan, which is the capital of Shandong Province and a typical city in the North China Plain. The PM2.5 samples were analyzed for BSOA(isoprene(SOAI) and monoterpenes(SOAM)) and ASOA(aromatic(SOAA)) tracers. The concentrations of the SOAAtracer(1.1 ± 1.0 ng/m3) were lowest, and those of SOAItracers(41.8 ± 86.2 ng/m3) were highest, with the concentrations of SOAMtracers(19.4 ± 9.9 ng/m3) being intermediate. The SOAItracers were more abundant in the summer and less abundant in the winter. Both SOAIand SOAMincreased with increasing ozone level but decreased with increasing NOx level. Correlation analysis revealed a good correlation between 2,3-dihydroxy-4-oxopentanoic acid and levoglucosan levels in three seasons. These results suggested that biomass burning activities occurring in the NCP can enhance the emissions of aromatics and should be controlled, especially in the autumn and winter. SOA tracers were classified according to pollution degree, and the results showed that as pollution increases, the contributions of SOAAincrease. These results indicate that reducing anthropogenic emissions is necessary to prevent SOA pollution, especially during heavy pollution episodes.Yusi Liu Xingru Li Guiqian Tang Lili Wang Bo Lv Xueqing Guo Yuesi Wang 2019Journal of Environmental Sciences2019,31,6:6
5Interactions between water vapor and atmospheric aerosols have key roles in air quality and climate change显示文摘INTRODUCTION Atmospheric aerosols,which are ubiquitous in the planetary boundary layer, have received much attention due to their effects on visibility,climate and human health.Water,a semi-volatile species,is ubiquitous in the atmosphere as well.The interaction between water vapor and aerosols plays a key role in determining the aerosol properties in the atmosphere and therefore has great effects on both air quality (Fig.la and b)and climate change (Fig.lc),which is depicted in Fig.1 as a function of atmospheric relative humidity (RH)and temperature.Zhijun Wu Jie Chen Yu Wang Yishu Zhu Yuechen Liu Bai Yao Yuanhang Zhang Min Hu 2018National Science Review2018,5,4:4
6The Effect of Super Volcanic Eruptions on Ozone Depletion in a Chemistry–Climate Model显示文摘With the gradual yet unequivocal phasing out of ozone depleting substances(ODSs), the environmental crisis caused by the discovery of an ozone hole over the Antarctic has lessened in severity and a promising recovery of the ozone layer is predicted in this century. However, strong volcanic activity can also cause ozone depletion that might be severe enough to threaten the existence of life on Earth. In this study, a transport model and a coupled chemistry–climate model were used to simulate the impacts of super volcanoes on ozone depletion. The volcanic eruptions in the experiments were the 1991 Mount Pinatubo eruption and a 100 × Pinatubo size eruption. The results show that the percentage of global mean total column ozone depletion in the 2050 RCP8.5 100 × Pinatubo scenario is approximately 6% compared to two years before the eruption and 6.4% in tropics. An identical simulation, 100 × Pinatubo eruption only with natural source ODSs, produces an ozone depletion of 2.5% compared to two years before the eruption, and with 4.4% loss in the tropics. Based on the model results,the reduced ODSs and stratospheric cooling lighten the ozone depletion after super volcanic eruption.Luyang XU Ke WEI Xue WU S. P. SMYSHLYAEV Wen CHEN V. Ya. GALIN 2019Advances in Atmospheric Sciences2019,36,8:3
7Characteristics of climate change in the “significant impact zone” affected by aerosols over eastern China in warm seasons显示文摘Through analysis of the distribution pattern and changing characteristics of atmospheric aerosols over the East Asia region during warm seasons in recent 20 a and beyond as well as their possible interac- tive relationship with a variety of meteorological elements, it is found that the high-value zone of aerosol optical depth derived from the Total Ozone Mapping Spectrometer (TOMS), its significant negative correlation zones in terms of sunshine duration (SD) and surface air temperature (SAT) and its significant positive correlation zones with low-level cloud amount (LCC) are co-located in the South China region during warm periods. Based on this finding, the region is referred to as a 'significant impact zone' (SI zone) affected by aerosols. Then, a comparative analysis is made on variation differ- ences of observed SAT, SD and LCC, etc. in different regions. It is also found that the LCC is increased and the SD is decreased within the 'SI zone' over eastern China during the warm season. These characteristics are more evident than those beyond the zone, while the warming trend within the zone is evidently weaker than that outside it. Studies show that since recent 20 a, under the influence of aerosols, the LCC tend to increase substantially with a clear decrease of SD and an unnoticeable warming trend within the 'SI zone'. Comparing with the climate change beyond the zone, the difference is significant. Therefore, the effects of atmospheric aerosols on climate is possibly one of the contri- butions to the difference of climate change existed between the southern and northern parts of the Eastern China during a warm season.SHI XiaoHui1, XU XiangDe1, XIE LiAn2 1 State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China 2 Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh NC27695-8208, USA 2008Science China Earth Sciences2008,51,5:2
8Anthropogenic Aerosol Pollution over the Eastern Slope of the Tibetan Plateau显示文摘In this study, a combination of satellite observations and reanalysis datasets is used to analyze the spatiotemporal distribution, classification and source of pollutants over the eastern slope of the Tibetan Plateau(ESTP). The aerosol optical depth(AOD) over the ESTP is extremely large and even larger than some important industrialized regions and deserts. The main aerosol component over the ESTP is sulfate, followed by carbonaceous and dust aerosols. Local emissions related to human activity directly contribute to the accumulation of sulfate and carbonaceous aerosols over the Sichuan Basin. In addition, in spring, abundant carbonaceous aerosols emitted from forest, grassland and savanna fires in Southeast Asia can be transported by the prevailing southwesterly wind to southern China and the ESTP. The dust AOD over the ESTP peaks in spring because of the transport from the Taklimakan and Gobi deserts. Additionally, the high aerosol loading over the ESTP is also directly related to the meteorological background. Due to the special topography, the terrain-driven circulation can trap aerosols in the Sichuan Basin and these aerosols can climb along the ESTP due to the perennial updraft. The aerosol loading is lowest in summer because of effective wet deposition induced by the strong precipitation and better dispersion conditions due to the larger vertical temperature gradients and ascending air movement enhanced by the plateau heat pump effect. In contrast,the aerosol loading is greatest in winter. Abundant anthropogenic aerosols over the ESTP may generate some climatic and environmental risks and consequently greatly influence the downstream regions.Rui JIA Min LUO Yuzhi LIU Qingzhe ZHU Shan HUA Chuqiao WU Tianbin SHAO 2019Advances in Atmospheric Sciences2019,36,8:2
9Optical and Radiative Properties of Aerosols during a Severe Haze Episode over the North China Plain in December 2016显示文摘The optical and radiative properties of aerosols during a severe haze episode from 15 to 22 December 2016 over Beijing, Shijiazhuang, and Jiaozuo in the North China Plain were analyzed based on the ground-based and satellite data, meteorological observations, and atmospheric environmental monitoring data. The aerosol optical depth at 500 nm was < 0.30 and increased to > 1.4 as the haze pollution developed. The ?ngstr?m exponent was > 0.80 for most of the study period. The daily single-scattering albedo was > 0.85 over all of the North China Plain on the most polluted days and was > 0.97 on some particular days. The volumes of fine and coarse mode particles during the haze event were approximately 0.05–0.21 and 0.01–0.43 μm3, respectively—that is, larger than those in the time without haze. The daily absorption aerosol optical depth was about 0.01–0.11 in Beijing, 0.01–0.13 in Shijiazhuang, and0.01–0.04 in Jiaozuo, and the average absorption ?ngstr?m exponent varied between 0.6 and 2.0. The aerosol radiative forcing at the bottom of the atmosphere varied from –23 to –227, –34 to –199, and –29 to –191 W m–2 for the whole haze period, while the aerosol radiative forcing at the top of the atmosphere varied from –4 to –98, –10 to –51,and –21 to –143 W m–2 in Beijing, Shijiazhuang, and Jiaozuo, respectively. Satellite observations showed that smoke,polluted dust, and polluted continental components of aerosols may aggravate air pollution during haze episodes. The analysis of the potential source contribution function and concentration-weighted trajectory showed that the contribution from local emissions and pollutants transport from upstream areas were 190–450 and 100–410 μg m^(–3), respectively.Yu ZHENG Huizheng CHE Leiku YANG Jing CHEN Yaqiang WANG Xiangao XIA Hujia ZHAO Hong WANG Deying WANG Ke GUI Linchang AN Tianze SUN Jie YU Xiang KUANG Xin LI Enwei SUN Dapeng ZHAO Dongsen YANG Zengyuan GUO Tianliang ZHAO Xiaoye ZHANG 2017Journal of Meteorological Research2017,31,6:2
10A CFD study of the transport and fate of airborne droplets in a ventilated office:The role of droplet−droplet interactions显示文摘Previous studies reported that specially designed ventilation systems provide good air quality and safe environment by removing airborne droplets that contain viruses expelled by infected people.These water droplets can be stable in the environment and remain suspended in air for prolonged periods.Encounters between droplets may occur and droplet interactions should be considered.However,the previous studies focused on other physical phenomena(air flow,drag force,evaporation)for droplet transport and neglected droplet interactions.In this work,we used computational fluid dynamics(CFD)to simulate the transport and fate of airborne droplets expelled by an asymptomatic person and considered droplet interactions.Droplet drag with turbulence for prediction of transport and fate of droplets indicated that the turbulence increased the transport of 1μm droplets,whereas it decreased the transport of 50μm droplets.In contrast to only considering drag and turbulence,consideration of droplet interactions tended to increase both the transport and fate.Although the length scale of the office is much larger than the droplet sizes,the droplet interactions,which occurred at the initial stages of release when droplet separation distances were shorter,had a significant effect in droplet fate by considerably manipulating the final locations on surfaces where droplets adhered.Therefore,it is proposed that when an exact prediction of transport and fate is required,especially for high droplet concentrations,the effects of droplet interactions should not be ignored.Allan Gomez-Flores Gukhwa Hwang Sadia Ilyas Hyunjung Kim 2022Frontiers of Environmental Science & Engineering2022,16,3:2
11Effects of two transition metal sulfate salts on secondary organic aerosol formation in toluene/NOx photooxidation显示文摘Aerosol phase reactions play a very important role on secondary organic aerosol (SOA) formation, and metal-containing aerosols are important components in the atmosphere. In this study, we tested the effects of two transition metal sulfate salts, manganese sulfate (MnSO4) and zinc sulfate (ZnSO4), on the photochemical reactions of a toluene/NOx photooxidation system in a 2 m3 smog chamber. By comparing photochemical reaction products of experiments with and without transition metal sulfate seed aerosols, we evaluated the effects of transition metal sulfate seed aerosols on toluene consumption, NOx conversion and the formation of ozone and SOA. MnSO4 and ZnSO4 seed aerosols were found to have similar effects on photochemical reactions, both enhance the SOA production, while showing negligible effects on the gas phase compounds. These observations are consistent when varying metal sulfate aerosol concentrations. This is attributed to the catalytic effects of MnSO4 and ZnSO4 seed aerosols which may enhance the formation of condensable semivolatile compounds. Their subsequent partitioning into the aerosol phase leads to the observed SOA formation enhancement.Biwu CHU Jiming HAO Junhua LI Hideto TAKEKAWA Kun WANG Jingkun JIANG 2013Frontiers of Environmental Science & Engineering2013,7,1:2
12Atmospheric Particle Hygroscopicity and the Influence by Oxidation State of Organic Aerosols in Urban Beijing显示文摘A hygroscopic tandem differentialmobility analyser(H-TDMA)was used to observe the sizeresolved hygroscopic characteristics of submicron particles in January and April 2018 in urban Beijing.The probability distribution of the hygroscopic growth factor(HGF-PDF)in winter and spring usually showed a bimodal pattern,with more hygroscopic mode(MH)being more dominant.The seasonal variation in particle hygroscopicity was related to the origin of air mass,which received polluted southerly air masses in spring and clean northwesterly air masses in winter.Particles showed stronger hygroscopic behaviour during heavy pollution episodes(HPEs)with elevated concentrations of secondary aerosols,especially higher mass fraction of nitrate,which were indicated using the PM2.5(particulate matter with diameter below 2.5μm)mass concentration normalised by CO mass concentration.The hygroscopic parameter(κ)values were calculated using H-TDMA(κhtdma)and chemical composition(κchem).The closure study showed thatκchem was overestimated in winter afternoon when compared withκhtdma,because the organic particle hygroscopic parameter(κorg)was overestimated in the calculations.It was influenced by the presence of a high concentration of hydrocarbon-like organic aerosol(HOA)with a weak water uptake ability.A positive relationship was observed betweenκorg and the ratio of oxygenated organic aerosol(OOA)and HOA,thereby indicating that the strong oxidation state enhanced the hygroscopicity of the particles.This study revealed the effect of local emission sources and secondary aerosol formation processes on particle hygroscopicity,which is of great significance for understanding the pollution formation mechanism in the North China Plain.Sinan Zhang Xiaojing Shen Junying Sun Yangmei Zhang Xiaoye Zhang Can Xia Xinyao Hu Junting Zhong Jialing Wang Shuo Liu 2023Journal of Environmental Sciences2023,,2:1
13Fate and transport of enveloped viruses in indoor built spaces-through understanding vaccinia virus and surface interactions显示文摘The current coronavirus disease 2019(COVID-19)pandemic has reinforced the necessity of understanding and establishing baseline information on the fate and transport mechanisms of viruses under indoor environmental conditions.Mechanisms governing virus interactions in built spaces have thus far been established based on our knowledge on the interaction of inorganic particles in indoor spaces and do not include characteristics specific to viruses.Studies have explored the biological and kinetic processes of microbes’attachments on surfaces in other fields but not in the built environment.There is also extensive literature on the influence of indoor architecture on air flow,temperature profiles,and forces influencing aerosol transport.Bridging the gap between these fields will lead to the generation of novel frameworks,methodologies and know-how that can identify undiscovered pathways taken by viruses and other microbes in the built environment.Our study summarizes the assessment of the influence of surface properties on the adhesion kinetics of vaccinia virus on gold,silica,glass,and stainless-steel surfaces.We found that on gold the virus layer was more viscoelastic compared to stainless-steel.There was negligible removal of the layer from the stainless-steel surface compared to the others.The results further highlight the importance of converging different fields of research to assess the fate and transport of microbes in indoor built spaces.Dahae Seong Monchupa Kingsak Yuan Lin Qian Wang Shamia Hoque 2021Biomaterials Translational2021,2,1:1
14Variation characteristics of stratospheric aerosols due to the Pinatubo eruption by SAGE Ⅱ data显示文摘Both theoretical and observational studies reveal that the stratospheric volcanic aerosols have important impact on global climate change. The volcanic aerosols can also exert some influences on remote se(?)sing of the atmosphere-earth system . So it is necessary to monitor the aerosol variation in the stratosphere due to the volcanic eruption.陈洪滨 吕达仁 许丽生 1995Chinese Science Bulletin1995,40,3:1
15Analysis of South Asian Monsoons within the Context of Increasing Regional Black Carbon Aerosols显示文摘South Asian monsoons were analyzed within the context of increasing emissions of black carbon(BC) aerosols using a global atmospheric general circulation model.The BC aerosols were allowed to increase only over the south Asian domain to analyze the impacts of regional black carbon over the climatological patterns of monsoons.The black carbon significantly absorbed the incoming short wave radiation in the atmosphere,a result that is consistent with previous studies.Pre-monsoon(March-April-May) rainfall showed positive anomalies,particularly for some coastal regions of India.The summer(June-July-August) rainfall anomalies were negative over the northern Himalayas,Myanmar,southern China,and most of the regions below 20°N due to the decrease in temperature gradients induced by the absorption of radiation by BC aerosols.The vertical wind speed anomalies indicated that these regions experienced less convection,which reduces the precipitation efficiency of the monsoon system in South Asia.Rashed MAHMOOD 2010Atmospheric and Oceanic Science Letters2010,3,4:1
16Heterogeneous chemistry of trace atmospheric gases on atmospheric aerosols:An overview显示文摘Due to altering the budget of important trace gases and changing the composition of atmospheric aerosols,heterogeneous reactions between trace gases and liquid/solid aerosols have become an important subject of atmospheric science in recent years.However,the kinetics and mechanism of these reactions have not been well-understood yet.In recent years,we have established an integrated method to study a series of atmospheric heterogeneous reactions under control atmospheric conditions.Using on-line techniques,such as Diffuse Reflectance Infrared Fourier Transform spectroscopy,Raman microspectrometry and Knudsen cell,the heterogeneous reactions of a series of trace gases(NO2,SO2,H2O2,DMS,C2H5 I and Monocarboxylic acids)on mineral oxides and black carbon were investigated.The uptake coefficients and mechanisms at different atmospheric conditions(temperature,relative humidity and reactant concentration)were obtained.In addition,a home-made equipment named rotated wetted-wall reactor was designed for the in situinvestigations of the uptake of volatile organic compounds into the H2SO4 solution and H2SO4/H2O2 mixed solution.In this review,we present the main results obtained in our laboratory studies and propose some challenges that still exist in the heterogeneous reaction studies.GE MaoFa WU LingYan TONG ShengRui LIU QiFan WANG WeiGang 2015Science Foundation in China2015,23,3:1
17Drug delivery interfaces:A way to optimize inhalation therapy in spontaneously breathing children显示文摘There are several different types of drug delivery interfaces available on the market.Using the right interface for aerosol drug delivery to children is essential for effective inhalation therapy.However,clinicians usually focus on selecting the right drug-device combination and often overlook the importance of interface selection that lead to suboptimal drug delivery and therapeutic response in neonates and pediatrics.Therefore,it is necessary to critically assess each interface and understand its advantage and disadvantages in aerosol drug delivery to this patient population.The purpose of this paper is to provide a critical assessment of drug delivery interfaces used for the treatment of children with pulmonary diseases by emphasizing advantages and problems associated with their use during inhalation therapy.Arzu Ari 2016World Journal of Clinical Pediatrics2016,5,3:1
18A study of the chemical composition and transport of marine aerosols over the ocean near China显示文摘In this paper the authors cite the aerosol samples collected with a KA-200 Anderson cascade Impactor and a KB-120 sampler during the first cruise of the Kuroshio investigation operated by the People’s Republic of China and Japan cooperative program, from July 23 to August 21, 1987. The concentration size distributions and composition of marine aerosols over the Kuroshio area are analyzed. Neutron activation analysis is used to determine the elemental composition of the aerosols. The authors also discuss some characteristics of marine aerosols relating to long-range transport of crustal and anthropogenic elements from the continent to the remote ocean. Analytical results indicate that elements Al, Fe, Sc and Sb over this area are obviously influenced by the continent of Asia, and the size distributions are changed after long-range transport. The concentration of large particles increase. The concentrations of the elements C1 and Na are closely related to ocean conditions; the source of the elements ClZhang Ni, Zhou Mingyu, Lu Naiping, F. P. Parungo, Wen Yupu, Yang Shaojing, Yang Yinan and Chen Binru National Research Center for Marine Environmental Forecasts, State Oceanic Administration, Beijing, ChinaNational Oceanic and Atmospheric Administration, Environmental Research Laboratories, Air Resources Laboratory, Boulder,CO, U.S. A.Academy of Meteorological Sciences, State Meteorological Administration, Beijing, ChinaInstitute of High Energy Physics, Academia Sinica, Beijing, China 1991Acta Oceanologica Sinica1991,10,3:1
19Information Extraction of Bionic Camera-Based Polarization Navigation Patterns Under Noisy Weather Conditions显示文摘Light polarization is the phenomenon that describes the oscillations and orientations of the light waves.Polarized light is a source of substantial cue for navigation in many marine and land-dwelling animals.This work investigates the challenges of obtaining information regarding polarization under various conditions by observing the phenomenology of the ommatidium in many insects.Noisy conditions can be because of haze or the presence of clouds in the atmosphere.Aerosol molecules are greater in volume and scale in such atmospheric conditions.When sunlight crosses through these molecules of aerosol,its polarization information is distorted.The distorted pattern has a little or no information on neutral points of light polarization.On the basis of the relationship bet ween wavelength of sunlight and polarization,we propose a novel hue based color mixing(HBCM)model to calculate the polarization information and orientation information more accurately and robustly.This method improves the symmetries of polarization patterns and eliminates the effect of noises.Symmetries of polarization patterns are compared with red,green and blue(RGB)spectrum and these differences are quantified and compared especially under high noisy weather conditions.AH SAN Muhammad 蔡云泽 张卫东 2020Journal of Shanghai Jiaotong university(Science)2020,25,1:1
20South-hemispheric marine aerosol Hg and S isotope compositions reveal different oxidation pathways显示文摘Particle-bound mercury(PBM)records the oxidation of elemental mercury,of which the main oxidation pathways(Br∙/Cl∙/OH∙/O3)remain unclear,especially in the Southern Hemisphere.Here,we present latitudinal covariations of Hg and Sisotopic anomalies in cross-hemispheric marine aerosols that evidence an equator-to-poleward transition of Hg oxidants from OH∙/O3 in tropics to Br∙/Cl∙in polar regions highlighting thus the presence of distinct oxidation processes producing PBM.The correlations between Hg,S and O-isotopic compositions measured in PBM,sulfates and nitrates respectively within the aerosols highlight the implication of common oxidants in their formations at different latitudes.Our results open a new window to better quantify the present-day atmospheric Hg,S and N budgets and to evaluate the influences of aerosols on climate and ecosystems once the isotopic fractionations associated with each process have been determined.David AuYang Jiubin Chen Wang Zheng Yanxu Zhang Guitao Shi Jeroen ESonke Pierre Cartigny Hongming Cai Wei Yuan Liangzhi Liu Pengxue Gai Congqiang Liu 2022National Science Open2022,1,2:1
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