WorldWideScience

Sample records for aerosol wastes

  1. AEROSOL BEHAVIOR IN CHROMIUM WASTE INCINERATION

    Institute of Scientific and Technical Information of China (English)

    Suyuan Yu

    2003-01-01

    Cr2O3 is considered as the dominant incineration product during the combustion disposal of chromium waste. A hydrogen/air diffusion flame was employed to simulate the industrial process of incineration. Cr2O3 aerosols were generated inside the flame by the gas phase reaction of chromium and oxygen. Chromium came from the rapid decomposition of chromium hexacarbonyl (Cr(CO)6) at room temperature and was carried into the combustion chamber by hydrogen. Aerosol and clusters can then be easily formed in the flame by nucleation and coagulation. A two dimensional Discrete-Sectional Model (DSM) was adopted to calculate the Cr2O3 aerosol behavior. The experimental measurement method was Dynamic Light Scattering. The numerically predicted results agreed well with those of the experimental measurement. Both results show that the Cr2O3 aerosol size reached about 70 nanometers at the flame top.

  2. The aerosol radiative effects of uncontrolled combustion of domestic waste

    Science.gov (United States)

    Kodros, John K.; Cucinotta, Rachel; Ridley, David A.; Wiedinmyer, Christine; Pierce, Jeffrey R.

    2016-06-01

    Open, uncontrolled combustion of domestic waste is a potentially significant source of aerosol; however, this aerosol source is not generally included in many global emissions inventories. To provide a first estimate of the aerosol radiative impacts from domestic-waste combustion, we incorporate the Wiedinmyer et al. (2014) emissions inventory into GEOS-Chem-TOMAS, a global chemical-transport model with online aerosol microphysics. We find domestic-waste combustion increases global-mean black carbon and organic aerosol concentrations by 8 and 6 %, respectively, and by greater than 40 % in some regions. Due to uncertainties regarding aerosol optical properties, we estimate the globally averaged aerosol direct radiative effect to range from -5 to -20 mW m-2; however, this range increases from -40 to +4 mW m-2 when we consider uncertainties in emission mass and size distribution. In some regions with significant waste combustion, such as India and China, the aerosol direct radiative effect may exceed -0.4 W m-2. Similarly, we estimate a cloud-albedo aerosol indirect effect of -13 mW m-2, with a range of -4 to -49 mW m-2 due to emission uncertainties. In the regions with significant waste combustion, the cloud-albedo aerosol indirect effect may exceed -0.4 W m-2.

  3. On use of the method of acoustic coagulation of aerosols for purification of gaseous wastes from highly dispersed radioactive aerosols

    International Nuclear Information System (INIS)

    Acoustic coagulation of radioactive highly dispersed aerosols was investigated experimentally. Dispersive composition of aerosols before and after systems of collection by standard methods was determined. Efficiency of purification of gaseous wastes from radioactive highly dispersed aerosols using the method of acoustic coagulation in conjunction with standard purification methods was estimated. This method permitted to raise an efficiency of purification of gaseous flows from difficultly collected radioactive aerosols with particle sizes 2

  4. Combustion aerosols from municipal waste incineration - Effect of fuel feedstock and plant operation

    DEFF Research Database (Denmark)

    Zeuthen, J.H.; Pedersen, Anne Juul; Hansen, Jørn;

    2007-01-01

    Combustion aerosols were measured in a 22MW ( thermal energy) municipal waste incinerator. Different types of waste fractions were added to a base- load waste and the effect on aerosol formation was measured. The waste fractions applied were: PVC plastic, pressure- impregnated wood, shoes, salt...... concentration was stable and close to the reference PM2.5- value of 252 +/- 21mg= m(3) ( std. T, P). The total number concentration deviated during runs and between runs spanning from 43.10(6) to 87 . 10(6)#/cm(3)( std. T, P). The aerosols formed were mixtures of dense and aggregated particles in all tests. The...

  5. Investigation of the tracers for plastic-enriched waste burning aerosols

    Science.gov (United States)

    Kumar, Sudhanshu; Aggarwal, Shankar G.; Gupta, Prabhat K.; Kawamura, Kimitaka

    2015-05-01

    To better identify the tracers for open-waste burning (OWB) aerosols, we have conducted aerosol sampling at 2 landfill sites, i.e., Okhla and Bhalswa in New Delhi. The metals such as, As, Cd, Sb and Sn, which have been observed almost negligible in remote aerosols, are found abundantly in these OWB aerosol samples (n = 26), i.e., 60 ± 65, 41 ± 53, 537 ± 847 and 1325 ± 1218 ng m-3, respectively. Samples (n = 20) collected at urban locations in New Delhi, i.e., at Employees' State Insurance (ESI) hospital and National Physical Laboratory (NPL) also show high abundances of these metals in the particles. Filter samples are also analyzed for water-soluble dicarboxylic acids (C2-C12) and related compounds (oxocarboxylic acids and α-dicarbonyls). Terephthalic acid (tPh) was found to account for more than 77% of total diacids determined in OWB aerosols. However, such a high abundance of tPh is not observed in aerosols collected at urban sites. Instead, phthalic acid (Ph) was found as the third/fourth most abundant diacid (∼3%) following C2 (>70%) and C4 (>12%) in these waste burning influenced urban aerosols. A possible secondary formation pathway of Ph by photo-degradation of phthalate ester (di-2-ethylhexyl phthalate) in plastic-waste burning aerosol is suggested. Ionic composition of OWB aerosols showed that Cl- is the most abundant ion (40 ± 8% of total ions determined). The correlation studies of the potential metals with the organic tracers of garbage burning, i.e., phthalic, isophthalic and terephthalic acids show that especially Sn can be used as marker for tracing the plastic-enriched waste burning aerosols.

  6. The formation of aerosol particles during combustion of biomass and waste. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hjerrild Zeuthen, J.

    2007-05-15

    This thesis describes the formation of aerosol particles during combustion of biomass and waste. The formation of aerosol particles is investigated by studying condensation of alkali salts from synthetic flue gasses in a laboratory tubular furnace. In this so-called laminar flow aerosol condenser-furnace gaseous alkali chlorides are mixed with sulphur dioxide, water vapour and oxygen. At high temperatures the alkali chloride reacts with sulphur dioxide to form alkali sulphate. During subsequent cooling of the synthetic flue gas the chlorides and sulphates condense either as deposits on walls or on other particles or directly from the gas phase by homogenous nucleation. A previously developed computer code for simulation of one-component nucleation of particles in a cylindrical laminar flow is extended to include a homogeneous gas phase reaction to produce gaseous alkali sulphate. The formation of aerosol particles during full-scale combustion of wheat straw is investigated in a 100 MW grate-fired boiler. Finally, aerosols from incineration of waste are investigated during full-scale combustion of municipal waste in a 22 MW grate-fired unit. (BA)

  7. Aerosol particle transport modeling for preclosure safety studies of nuclear waste repositories

    International Nuclear Information System (INIS)

    An important concern for preclosure safety analysis of a nuclear waste repository is the potential release to the environment of respirable aerosol particles. Such particles, less than 10 μm in aerodynamic diameter, may have significant adverse health effects if inhaled. To assess the potential health effects of these particles, it is not sufficient to determine the mass fraction of respirable aerosol. The chemical composition of the particles is also of importance since different radionuclides may pose vastly different health hazards. Thus, models are needed to determine under normal and accident conditions the particle size and the chemical composition distributions of aerosol particles as a function of time and of position in the repository. In this work a multicomponent sectional aerosol model is used to determine the aerosol particle size and composition distributions in the repository. A range of aerosol mass releases with varying mean particle sizes and chemical compositions is used to demonstrate the sensitivities and uncertainties of the model. Decontamination factors for some locations in the repository are presented. 8 refs., 1 tab

  8. Experience with Aerosol Generation During Rotary Mode Core Sampling in the Hanford Single Shell Waste Tanks

    International Nuclear Information System (INIS)

    This document provides data on aerosol concentrations in tank head spaces, total mass of aerosols in the tank head space and mass of aerosols sent to the exhauster during Rotary Mode Core Sampling from November 1994 through April 1999

  9. Aerosol-Assisted Extraction of Silicon Nanoparticles from Wafer Slicing Waste for Lithium Ion Batteries

    Science.gov (United States)

    Jang, Hee Dong; Kim, Hyekyoung; Chang, Hankwon; Kim, Jiwoong; Roh, Kee Min; Choi, Ji-Hyuk; Cho, Bong-Gyoo; Park, Eunjun; Kim, Hansu; Luo, Jiayan; Huang, Jiaxing

    2015-01-01

    A large amount of silicon debris particles are generated during the slicing of silicon ingots into thin wafers for the fabrication of integrated-circuit chips and solar cells. This results in a significant loss of valuable materials at about 40% of the mass of ingots. In addition, a hazardous silicon sludge waste is produced containing largely debris of silicon, and silicon carbide, which is a common cutting material on the slicing saw. Efforts in material recovery from the sludge and recycling have been largely directed towards converting silicon or silicon carbide into other chemicals. Here, we report an aerosol-assisted method to extract silicon nanoparticles from such sludge wastes and their use in lithium ion battery applications. Using an ultrasonic spray-drying method, silicon nanoparticles can be directly recovered from the mixture with high efficiency and high purity for making lithium ion battery anode. The work here demonstrated a relatively low cost approach to turn wafer slicing wastes into much higher value-added materials for energy applications, which also helps to increase the sustainability of semiconductor material and device manufacturing. PMID:25819285

  10. A study of inter-particle bonds in dry bauxite waste resulting in atmospheric aerosols

    Science.gov (United States)

    Wagh, Arun S.; Thompson, Bentley

    1988-02-01

    Bauxite and Alumina production are one of the main activities of several third world countries such as Jamaica, Brazil, India, Guinea, eastern European countries such as Hungary and Rumania and advanced countries such as Australia, West Germany, Japan and the United States. The mining operations lead to dust pollution, but the refining of bauxite to alumina yield large amounts of highly caustic sludge waste, called "Red Mud". Millions of tons of the waste produced in every country are stored in containment dams or natural valleys. This leads to ground water pollution, destruction of plant and bird life and is hazardous to human settlement in earthquake prone regions like Jamaica. As a result several companies have been looking into dry mud stacking which involves thickening the mud in the refining plants and sprying it on the slopes to sun dry it. Typically it involves a drying field of about two hundred acres, which could act as a potential source of caustic dust. In Jamaica one company has started disposing of the mud in this way. The aerosol formation from such areas depends mainly on the integrity of the top dry layers. Presently this is done by studying the approximate parameters such as the friability of the mud. However, following the recent advances in powder technology it has been possible for us to develop an instrument to study the average interparticle forces between the red mud particles. The instrument is based on the principle of a tensometer and a split cell is used to load specimens. A load cell is used to measure the force and a chart recorder is used for plotting separation and the force. The present study reports elemental composition of the dust and its health hazards. It also reports the physical measurement of the average interparticle force as a function of their separation in the Jamaican mud. The effect of ultraviolet radiation on the strength of the material is studied to see the effect of sun-drying of the waste. The five-fold increase

  11. Experience with Aerosol Generation During Rotary Mode Core Sampling in the Hanford Single Shell Waste Tanks

    International Nuclear Information System (INIS)

    This document provides data on aerosol concentrations in tank head spaces, total mass of aerosols in the tank head space and mass of aerosols sent to the exhauster during Rotary Mode Core Sampling from November 1994 through June 1999. A decontamination factor for the RMCS exhauster filter housing is calculated based on operation data

  12. Aerosols from high-temperature procedures illustrated by vitrification of high-level radioactive waste solutions at PAMELA: Sampling, analysis and evaluation

    International Nuclear Information System (INIS)

    Since October 1985, LEWC (low enriched waste concentrate) has been completely solidified at the PAMELA vitrification unit at Mol/Belgium. Since October 1986 PAMELA has been reprocessing HEWC (high enriched waste concentrate). The present study aimed at examining the behaviour of radioactive aerosols in the PAMELA waste gas system. For that purpose, the relative nuclide source term, the waste gas purification efficiency of the various components, and the retentivity of the whole system were measured and assessed. For aerosol sampling under highly active conditions, the remotely controllable rod probe sampling system SAPHIR was designed, developed, tested and successfully used. By means of SAPHIR 112 aerosol samples were taken from the PAMELA furnace waste gas and analyzed. Measurement of the purifying efficiency of the various waste gas filter stages required the installation of five isokinetically functioning sampling probes in the waste gas section. 54 waste gas samples were taken by means of diaphragm filters which, like the SAPHIR probes, were taken to Garching for analysis. The overall efficiency of PAMELA could only be assessed, because of the high purifying effects of the plant's waste gas purification system, by means of a continuous long-term sampling of one series from six gas washers, and by analyzing the applied absorber solutions. The separation degree of SAPHIR for aerosol particles of different size and density was calculated theoretically, and measured at an aerosol circulation test stand developed for this purpose. The analysis of the probes covered, in addition to direct radiometry, scanning electron microscopy with energy-dispersive X-ray micro-analysis. Particle analysis included the classification of the multi-particle system according to size and chemical composition, which enabled the establishment of element-specific aerosol particle size distributions. (orig./LU)

  13. Ferrocyanide Safety Program: Analysis of postulated energetic reactions and resultant aerosol generation in Hanford Site Waste Tanks

    International Nuclear Information System (INIS)

    This report reviews work done to estimate the possible consequences of postulated energetic reactions in ferrocyanide waste stored in underground tanks at the Hanford Site. The issue of explosive reactions was raised in the 1987 Environmental Impact Statement (EIS), where a detonation-like explosion was postulated for the purpose of defining an upper bound on dose consequences for various disposal options. A review of the explosion scenario by the General Accounting Office (GAO) indicated that the aerosol generation and consequent radioactive doses projected for the explosion postulated in the EIS were understated by one to two orders of magnitude. The US DOE has sponsored an extensive study of the hazard posed by uncontrolled exothermic reactions in ferrocyanide waste, and results obtained during the past three years have allowed this hazard to be more realistically assessed. The objective of this report is to summarize the improved knowledge base that now indicates that explosive or vigorous chemical reactions are not credible in the ferrocyanide waste stored in underground tanks. This improved understanding supports the decision not to proceed with further analyses or predictions of the consequences of such an event or with aerosol tests in support of such predictions. 53 refs., 2 tabs

  14. Determination of Aerosol Particle Diameter in Cementation Room of Radioactive Waste Management Instalation

    International Nuclear Information System (INIS)

    Determination of aerosol particle size distribution has been done using a low pressure cascade impactor with 8-stage metode. The aerosol was sampled with flow rate of 28.3 litre per minute during 4 hours. The counting and calculations result indicated that aerosol particle at compaction room have an aerodynamic median activity diameter (AMAD) between range (2.1 - 3.3) μm. This result could be used for detemine type of filter for contamination level monitoring and estimating the internal radiation level to workers from inhalation. (author)

  15. Distribution and health risks of polycyclic aromatic hydrocarbons (PAHs) in smoke aerosols from burning of selected garden wastes

    International Nuclear Information System (INIS)

    A study has been carried out to characterize polycyclic aromatic hydrocarbons emitted from the burning of five types of typical garden wastes viz, Bachang, Mango, Jackfruit, Jambu Air litter fall and a type of Grass. The samples were burned to the ember and respective smoke aerosols emitted during the burning period were sampled using high volume filtration on a pre-cleaned glass fibre filters. Polycyclic aromatic hydrocarbons (PAHs) were extracted using dichloromethane-methanol (3:1) as solvent and the extracts fractionated on silica-alumina column. Detection and quantification of PAHs compounds were carried out using GC-MS. Results indicated that burning resulted in the formation of significant amount of PAHs compounds in all samples; total PAHs compounds emitted were in the range of 0.41 to 42.2 μg/ m3. The major PAHs compound exhibited in all smoke samples were three to four rings PAHs (example fluoranthene and pyrene) with lesser amount of five to six rings (example benzo(a)pyrene and benzo(g,h,i) perylene) and two rings PAHs (example acenaphthylene). The BaP equivalency results showed that the potential health risk from these garden wastes smoke were very significant; total BaP equivalency values were in the range of 5.60 E+04 pg/ m3 - 4.98 E+06 pg/ m3 with Jambu Air smoke exhibited the highest potential health risk. (author)

  16. Aerosol-Assisted Extraction of Silicon Nanoparticles from Wafer Slicing Waste for Lithium Ion Batteries

    OpenAIRE

    Hee Dong Jang; Hyekyoung Kim; Hankwon Chang; Jiwoong Kim; Kee Min Roh; Ji-Hyuk Choi; Bong-Gyoo Cho; Eunjun Park; Hansu Kim; Jiayan Luo; Jiaxing Huang

    2015-01-01

    A large amount of silicon debris particles are generated during the slicing of silicon ingots into thin wafers for the fabrication of integrated-circuit chips and solar cells. This results in a significant loss of valuable materials at about 40% of the mass of ingots. In addition, a hazardous silicon sludge waste is produced containing largely debris of silicon, and silicon carbide, which is a common cutting material on the slicing saw. Efforts in material recovery from the sludge and recycli...

  17. Experimental Challenges and Successes in Measuring Aerosol Concentrations at Prototypic Spray Conditions Encountered at the Hanford Waste Treatment and Immobilization Plant - 13327

    International Nuclear Information System (INIS)

    To date, majority of the work done on measuring aerosol releases from failure of process piping was done using simple Newtonian fluids and small engineered-nozzles that do not accurately represent the fluids and breaches postulated during accident analysis at the Hanford Waste Treatment and Immobilization Plant (WTP). In addition, the majority of the work conducted in this area relies on in-spray measurements that neglect the effect of splatter and do not yield any information regarding aerosol generation rates from this additional mechanism. In order to estimate aerosol generation rates as well as reduce the uncertainties in estimating the aerosol release fractions over a broad range of breaches, fluid properties and operating conditions encountered at the WTP, the Pacific Northwest National Laboratory (PNNL) has designed, commissioned, and tested two experimental test stands. The first test stand, referred to as the large-scale test stand, was designed specifically to measure aerosol concentrations and release fractions under prototypic conditions of flow and pressure for a range of breaches postulated in the hazard analysis for 0.076 m (3-inch) process pipes. However, the size of the large-scale test stand, anticipated fluid loss during a breach, experimental risks, and costs associated with hazardous chemical simulant testing limited the large-scale test stand utility to water and a few non-hazardous physical simulants that did not fully span the particle size and rheological properties of the fluids encountered at the WTP. Overcoming these limitations and extending the range of simulants used, required designing and building a smaller test stand, which was installed and operated in a fume hood. This paper presents some of the features of both test stands, the experimental challenges encountered, and successes in measuring aerosol concentration in both test stands over a range of test conditions. (authors)

  18. Polar and non-polar organic aerosols from large-scale agricultural-waste burning emissions in Northern India: Implications to organic mass-to-organic carbon ratio.

    Science.gov (United States)

    Rajput, Prashant; Sarin, M M

    2014-05-01

    This study focuses on characteristics of organic aerosols (polar and non-polar) and total organic mass-to-organic carbon ratio (OM/OC) from post-harvest agricultural-waste (paddy- and wheat-residue) burning emissions in Northern India. Aerosol samples from an upwind location (Patiala: 30.2°N, 76.3°E) in the Indo-Gangetic Plain were analyzed for non-polar and polar fractions of organic carbon (OC1 and OC2) and their respective mass (OM1 and OM2). On average, polar organic aerosols (OM2) contribute nearly 85% of the total organic mass (OM) from the paddy- and wheat-residue burning emissions. The water-soluble-OC (WSOC) to OC2 ratio, within the analytical uncertainty, is close to 1 from both paddy- and wheat-residue burning emissions. However, temporal variability and relatively low WSOC/OC2 ratio (Av: 0.67±0.06) is attributed to high moisture content and poor combustion efficiency during paddy-residue burning, indicating significant contribution (∼30%) of aromatic carbon to OC2. The OM/OC ratio for non-polar (OM1/OC1∼1.2) and polar organic aerosols (OM2/OC2∼2.2), hitherto unknown for open agricultural-waste burning emissions, is documented in this study. The total OM/OC ratio is nearly identical, 1.9±0.2 and 1.8±0.2, from paddy- and wheat-residue burning emissions. PMID:24331033

  19. Aerosol Formation from High-Pressure Sprays for Supporting the Safety Analysis for the Hanford Waste Treatment and Immobilization Plant - 13183

    International Nuclear Information System (INIS)

    The Waste Treatment and Immobilization Plant (WTP) at Hanford is being designed and built to pretreat and vitrify waste currently stored in underground tanks at Hanford. One of the postulated events in the hazard analysis for the WTP is a breach in process piping that produces a pressurized spray with small droplets that can be transported into ventilation systems. Literature correlations are currently used for estimating the generation rate and size distribution of aerosol droplets in postulated releases. These correlations, however, are based on results obtained from small engineered nozzles using Newtonian liquids that do not contain slurry particles and thus do not represent the fluids and breaches in the WTP. A test program was developed to measure the generation rate, and the release fraction which is the ratio of generation rate to spray flow rate, of droplets suspended in a test chamber and droplet size distribution from prototypic sprays. A novel test method was developed to allow measurement of sprays from small to large breaches and also includes the effect of aerosol generation from splatter when the spray impacts on walls. Results show that the release fraction decreases with increasing orifice area, though with a weaker dependence on orifice area than the currently-used correlation. A comparison of water sprays to slurry sprays with 8 to 20 wt% gibbsite or boehmite particles shows that the presence of slurry particles depresses the release fraction compared to water for droplets above 10 μm and increases the release fraction below this droplet size. (authors)

  20. Aerosol filtration

    International Nuclear Information System (INIS)

    This report summarizes the work on the development of fibre metallic prefilters to be placed upstream of HEPA filters for the exhaust gases of nuclear process plants. Investigations at ambient and high temperature were carried out. Measurements of the filtration performance of Bekipor porous webs and sintered mats were performed in the AFLT (aerosol filtration at low temperature) unit with a throughput of 15 m3/h. A parametric study on the influence of particle size, fibre diameter, number of layers and superficial velocity led to the optimum choice of the working parameters. Three selected filter types were then tested with polydisperse aerosols using a candle-type filter configuration or a flat-type filter configuration. The small-diameter candle type is not well suited for a spraying nozzles regeneration system so that only the flat-type filter was retained for high-temperature tests. A high-temperature test unit (AFHT) with a throughput of 8 to 10 m3/h at 4000C was used to test the three filter types with an aerosol generated by high-temperature calcination of a simulated nitric acid waste solution traced with 134Cs. The regeneration of the filter by spray washing and the effect of the regeneration on the filter performance was studied for the three filter types. The porous mats have a higher dust loading capacity than the sintered web which means that their regeneration frequency can be kept lower

  1. Characterization of flue gas, fly ash, aerosol and deposit compositions as a function of waste composition and grate operation

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; Zeuthen, Frederik Jacob; Frandsen, Flemming;

    2007-01-01

    metals, was then mixed with the reference fuel in the individual test runs. The dedicated waste fractions comprised NaCl (road salt), batteries, automotive shredder waste, CCA (Copper-Chromate-Arsenate)-impregnated wood, PVC plastics, and (leather) shoes. Test runs with varying operational parameters, e...

  2. Organic aerosols and inorganic species from post-harvest agricultural-waste burning emissions over northern India: impact on mass absorption efficiency of elemental carbon.

    Science.gov (United States)

    Rajput, Prashant; Sarin, M M; Sharma, Deepti; Singh, Darshan

    2014-01-01

    Atmospheric PM2.5 (particulate matter with aerodynamic diameter of ≤ 2.5 μm), collected from a source region [Patiala: 30.2 °N; 76.3 °E; 250 m above mean sea level] of emissions from post-harvest agricultural-waste (paddy-residue) burning in the Indo-Gangetic Plain (IGP), North India, has been studied for its chemical composition and impact on regional atmospheric radiative forcing. On average, organic aerosol mass accounts for 63% of PM2.5, whereas the contribution of elemental carbon (EC) is ∼3.5%. Sulphate, nitrate and ammonium contribute up to ∼85% of the total water-soluble inorganic species (WSIS), which constitutes ∼23% of PM2.5. The potassium-to-organic carbon ratio from paddy-residue burning emissions (KBB(+)/OC: 0.05 ± 0.01) is quite similar to that reported from Amazonian and Savanna forest-fires; whereas non-sea-salt-sulphate-to-OC ratio (nss-SO4(2-)/OC: 0.21) and nss-SO4(2-)/EC ratio of 2.6 are significantly higher (by factor of 5 to 8). The mass absorption efficiency of EC (3.8 ± 1.3 m(2) g(-1)) shows significant decrease with a parallel increase in the concentrations of organic aerosols and scattering species (sulphate and nitrate). A cross plot of OC/EC and nss-SO4(2-)/EC ratios show distinct differences for post-harvest burning emissions from paddy-residue as compared to those from fossil-fuel combustion sources in south-east Asia. PMID:25124269

  3. Resent Progress in Research on Calibration Instrument for Radioactive Aerosol Monitor

    Institute of Scientific and Technical Information of China (English)

    CHEN; Xi-lin; CHEN; Yong-yong; WU; Chang-ping; XING; Yu; MENG; Jun; YANG; Qiao-ling

    2013-01-01

    Radioactive aerosol monitors are widely used in monitoring the radioactivity concentration of the artificial nuclides in gaseous effluents from the nuclear facilities.An on-developing calibration instrument for radioactive aerosol monitors consists of an α and β aerosol generating unit,aerosol transferring unit,measurement unit of radioactivity concentration of aerosol for instruments calibrated and the waste gas

  4. Electrically Driven Technologies for Radioactive Aerosol Abatement

    Energy Technology Data Exchange (ETDEWEB)

    David W. DePaoli; Ofodike A. Ezekoye; Costas Tsouris; Valmor F. de Almeida

    2003-01-28

    The purpose of this research project was to develop an improved understanding of how electriexecy driven processes, including electrocoalescence, acoustic agglomeration, and electric filtration, may be employed to efficiently treat problems caused by the formation of aerosols during DOE waste treatment operations. The production of aerosols during treatment and retrieval operations in radioactive waste tanks and during thermal treatment operations such as calcination presents a significant problem of cost, worker exposure, potential for release, and increased waste volume.

  5. Organic aerosols

    International Nuclear Information System (INIS)

    Organic aerosols scatter solar radiation. They may also either enhance or decrease concentrations of cloud condensation nuclei. This paper summarizes observed concentrations of aerosols in remote continental and marine locations and provides estimates for the sources of organic aerosol matter. The anthropogenic sources of organic aerosols may be as large as the anthropogenic sources of sulfate aerosols, implying a similar magnitude of direct forcing of climate. The source estimates are highly uncertain and subject to revision in the future. A slow secondary source of organic aerosols of unknown origin may contribute to the observed oceanic concentrations. The role of organic aerosols acting as cloud condensation nuclei (CCN) is described and it is concluded that they may either enhance or decrease the ability of anthropogenic sulfate aerosols to act as CCN

  6. Marine aerosols

    OpenAIRE

    Saltzman, Es

    2009-01-01

    The aerosol over the world oceans plays an important role in determining the physical and chemical characteristics of the Earth's atmosphere and its interactions with the climate system. The oceans contribute to the aerosols in the overlying atmosphere by the production and emission of aerosol particles and precursor gases. The marine aerosol, in turn, influences the biogeochemistry of the surface ocean through long distance transport and deposition of terrestrial and marine-derived nutrients...

  7. Impact of agricultural waste burning in the Shandong Peninsula on carbonaceous aerosols in the Bohai Rim, China.

    Science.gov (United States)

    Wang, Xiaoping; Chen, Yingjun; Tian, Chongguo; Huang, Guopei; Fang, Yin; Zhang, Fan; Zong, Zheng; Li, Jun; Zhang, Gan

    2014-05-15

    A total of 11 5PM2.5 samples were collected for analyzing organic carbon (OC) and elemental carbon (EC) at Tuoji Island (TI), China from November 2011 to December 2012. The results showed that annual arithmetical means of OC and EC concentrations were 3.8 ± 2.7 and 2.2 ± 2.2 μg m(-3), which contributed 8% and 4% of PM2.5 mass concentrations, respectively. High EC concentrations occurred in winter, contributed mainly by EC outflow from the northwest source region, while high OC concentrations were found during spring, attributed largely to biofuel burning in the Shandong Peninsula, and short distance and favorable transport from the peninsula to the TI. Agricultural waste open burning in the peninsula caused the largest variability of OC concentration in summer. Eliminating agricultural field burning in the peninsula can reduce at least one-third of concentration levels and half of northward transport fluxes of OC and EC in Bohai Rim in summer. PMID:24607395

  8. Aerosol studies

    International Nuclear Information System (INIS)

    As part of the continuing studies of the effects of very severe reactor accidents, an effort was made to develop, test, and improve simple, effective, and inexpensive methods by which the average citizen, using only materials readily available, could protect his residence, himself, and his family from injury by toxic aerosols. The methods for protection against radioactive aerosols should be equally effective against a clandestine biological attack by terrorists. The results of the tests to date are limited to showing that spores of the harmless bacterium, bacillus globegii (BG), can be used as a simulant for the radioactive aerosols. An aerosol generator of Lauterbach type was developed which will produce an essentially monodisperse aerosol at the rate of 109 spores/min. Analytical techniques have been established which give reproducible results. Preliminary field tests have been conducted to check out the components of the system. Preliminary tests of protective devices, such as ordinary vacuum sweepers, have given protection factors of over 1000

  9. Stratospheric aerosols

    International Nuclear Information System (INIS)

    Stratospheric aerosol measurements can provide both spatial and temporal data of sufficient resolution to be of use in climate models. Relatively recent results from a wide range of instrument techniques for measuring stratospheric aerosol parameters are described. Such techniques include impactor sampling, lidar system sensing, filter sampling, photoelectric particle counting, satellite extinction-sensing using the sun as a source, and optical depth probing, at sites mainly removed from tropospheric aerosol sources. Some of these techniques have also had correlative and intercomparison studies. The main methods for determining the vertical profiles of stratospheric aerosols are outlined: lidar extinction measurements from satellites; impactor measurements from balloons and aircraft; and photoelectric particle counter measurements from balloons, aircraft, and rockets. The conversion of the lidar backscatter to stratospheric aerosol mass loading is referred to. Absolute measurements of total solar extinction from satellite orbits can be used to extract the aerosol extinction, and several examples of vertical profiles of extinction obtained with the SAGE satellite are given. Stratospheric mass loading can be inferred from extinction using approximate linear relationships but under restrictive conditions. Impactor sampling is essentially the only method in which the physical nature of the stratospheric aerosol is observed visually. Vertical profiles of stratospheric aerosol number concentration using impactor data are presented. Typical profiles using a dual-size-range photoelectric dustsonde particle counter are given for volcanically disturbed and inactive periods. Some measurements of the global distribution of stratospheric aerosols are also presented. Volatility measurements are described, indicating that stratospheric aerosols are composed primarily of about 75% sulfuric acid and 25% water

  10. Tropospheric Aerosols

    Science.gov (United States)

    Buseck, P. R.; Schwartz, S. E.

    2003-12-01

    It is widely believed that "On a clear day you can see forever," as proclaimed in the 1965 Broadway musical of the same name. While an admittedly beautiful thought, we all know that this concept is only figurative. Aside from Earth's curvature and Rayleigh scattering by air molecules, aerosols - colloidal suspensions of solid or liquid particles in a gas - limit our vision. Even on the clearest day, there are billions of aerosol particles per cubic meter of air.Atmospheric aerosols are commonly referred to as smoke, dust, haze, and smog, terms that are loosely reflective of their origin and composition. Aerosol particles have arisen naturally for eons from sea spray, volcanic emissions, wind entrainment of mineral dust, wildfires, and gas-to-particle conversion of hydrocarbons from plants and dimethylsulfide from the oceans. However, over the industrial period, the natural background aerosol has been greatly augmented by anthropogenic contributions, i.e., those produced by human activities. One manifestation of this impact is reduced visibility (Figure 1). Thus, perhaps more than in other realms of geochemistry, when considering the composition of the troposphere one must consider the effects of these activities. The atmosphere has become a reservoir for vast quantities of anthropogenic emissions that exert important perturbations on it and on the planetary ecosystem in general. Consequently, much recent research focuses on the effects of human activities on the atmosphere and, through them, on the environment and Earth's climate. For these reasons consideration of the geochemistry of the atmosphere, and of atmospheric aerosols in particular, must include the effects of human activities. (201K)Figure 1. Impairment of visibility by aerosols. Photographs at Yosemite National Park, California, USA. (a) Low aerosol concentration (particulate matter of aerodynamic diameter less than 2.5 μm, PM2.5=0.3 μg m-3; particulate matter of aerodynamic diameter less than 10

  11. Consequences of select boiling waste scenarios for waste feed delivery

    International Nuclear Information System (INIS)

    The purpose of this calculation is to quantify thermal phenomena and predict consequences for select double-shell tank (DST) heat-up scenarios for waste feed delivery safety applications. This work extends previous tank bump analyses [Epstein, et al., 2000; and Epstein, et al., 2000a] by focusing on selected scenarios in which extended loss of cooling leads to waste boiling and aerosol generation. The HADCRT code, Version 1.3, is used to provide a best-estimate, coupled simulation of both thermal-hydraulic and aerosol transport phenomena. The physical model employed considers boiling aerosol generation, aerosol agglomeration and gravitational sedimentation in the tank headspace, aerosol removal FR-om steam condensation, and aerosol transport FR-om the headspace to the environment and through ventilation flow paths. Thus, the net result of the calculation is the time history of aerosol release to the immediate vicinity of an underground DST

  12. Indoor aerosols

    DEFF Research Database (Denmark)

    Morawska, L.; Afshari, Alireza; N. Bae, G.;

    2013-01-01

    understanding of the risks posed by personal exposure to indoor aerosols. Limited studies assessing integrated daily residential exposure to just one particle size fraction, ultrafine particles, show that the contribution of indoor sources ranged from 19% to 76%. This indicates a strong dependence on resident...

  13. Characterization of PM2.5 particles originating from a modern waste incineration plant by factor analysis of chemical data, mass and black carbon in ambient aerosol

    DEFF Research Database (Denmark)

    Aboh, Innocent Joy Kwame; Henrikson, Dag; Laursen, Jens;

    In the city of Borås, which is a medium sized city in the south-western part of Sweden, a new modern plant for electricity and heat generation has recently been installed and optimised with respect to internal parameters of efficiency and economy. The direct emissions of gaseous pollutants which ...... bio-mass fired stoves, industrial emissions and long range transported aerosols are believed to contribute to the observed data. Oil combustion was identified as one of the major sources to Ni and V in the urban air....

  14. TOMS Absorbing Aerosol Index

    Data.gov (United States)

    Washington University St Louis — TOMS_AI_G is an aerosol related dataset derived from the Total Ozone Monitoring Satellite (TOMS) Sensor. The TOMS aerosol index arises from absorbing aerosols such...

  15. Aerosol Observation System

    Data.gov (United States)

    Oak Ridge National Laboratory — The aerosol observation system (AOS) is the primary Atmospheric Radiation Measurement (ARM) platform for in situ aerosol measurements at the surface. The principal...

  16. Data available for the evaluation of the risks related to the bio-aerosols emitted by the domestic wastes storage; Donnees disponibles pour l'evaluation des risques lies aux bioaerosols emis par les installations de stockage des dechets menagers et assimiles

    Energy Technology Data Exchange (ETDEWEB)

    Delery, L.

    2003-12-15

    The dusts production during exploitation in cells is the main source of bio-aerosols emission in storage centers. This report presents data on biological characterization of domestic wastes and the related atmospheric emissions. It concludes that the sanitary risk for the residents is weak and the 200 m area decided by the regulation is sufficient. Meanwhile it is recommended to control the emission levels during particularly meteorological conditions as humid, windy and not very sunny. (A.L.B.)

  17. Aerosol typing - key information from aerosol studies

    Science.gov (United States)

    Mona, Lucia; Kahn, Ralph; Papagiannopoulos, Nikolaos; Holzer-Popp, Thomas; Pappalardo, Gelsomina

    2016-04-01

    Aerosol typing is a key source of aerosol information from ground-based and satellite-borne instruments. Depending on the specific measurement technique, aerosol typing can be used as input for retrievals or represents an output for other applications. Typically aerosol retrievals require some a priori or external aerosol type information. The accuracy of the derived aerosol products strongly depends on the reliability of these assumptions. Different sensors can make use of different aerosol type inputs. A critical review and harmonization of these procedures could significantly reduce related uncertainties. On the other hand, satellite measurements in recent years are providing valuable information about the global distribution of aerosol types, showing for example the main source regions and typical transport paths. Climatological studies of aerosol load at global and regional scales often rely on inferred aerosol type. There is still a high degree of inhomogeneity among satellite aerosol typing schemes, which makes the use different sensor datasets in a consistent way difficult. Knowledge of the 4d aerosol type distribution at these scales is essential for understanding the impact of different aerosol sources on climate, precipitation and air quality. All this information is needed for planning upcoming aerosol emissions policies. The exchange of expertise and the communication among satellite and ground-based measurement communities is fundamental for improving long-term dataset consistency, and for reducing aerosol type distribution uncertainties. Aerosol typing has been recognized as one of its high-priority activities of the AEROSAT (International Satellite Aerosol Science Network, http://aero-sat.org/) initiative. In the AEROSAT framework, a first critical review of aerosol typing procedures has been carried out. The review underlines the high heterogeneity in many aspects: approach, nomenclature, assumed number of components and parameters used for the

  18. Aerosol mobility size spectrometer

    Science.gov (United States)

    Wang, Jian; Kulkarni, Pramod

    2007-11-20

    A device for measuring aerosol size distribution within a sample containing aerosol particles. The device generally includes a spectrometer housing defining an interior chamber and a camera for recording aerosol size streams exiting the chamber. The housing includes an inlet for introducing a flow medium into the chamber in a flow direction, an aerosol injection port adjacent the inlet for introducing a charged aerosol sample into the chamber, a separation section for applying an electric field to the aerosol sample across the flow direction and an outlet opposite the inlet. In the separation section, the aerosol sample becomes entrained in the flow medium and the aerosol particles within the aerosol sample are separated by size into a plurality of aerosol flow streams under the influence of the electric field. The camera is disposed adjacent the housing outlet for optically detecting a relative position of at least one aerosol flow stream exiting the outlet and for optically detecting the number of aerosol particles within the at least one aerosol flow stream.

  19. Facility of aerosol filtration

    International Nuclear Information System (INIS)

    Said invention relates to a facility of aerosol filtration, particularly of sodium aerosols. Said facility is of special interest for fast reactors where sodium fires involve the possibility of high concentrations of sodium aerosols which soon clog up conventional filters. The facility intended for continuous operation, includes at the pre-filtering stage, means for increasing the size of the aerosol particles and separating clustered particles (cyclone separator)

  20. Solidification of highly active wastes

    International Nuclear Information System (INIS)

    This document contains the annual reports for the contracts: (A) Glass Technology; (B) Calcination of Highly Active Waste Liquors; (C) Formation and Trapping of Volatile Ruthenium; (D) Deposition of Ruthenium; (E) Enhancement of Off-Gas Aerosol Collection; (F) Volatilisation of Cs, Tc and Te in High Level Waste Vitrification. (author)

  1. Solidification of highly active wastes

    International Nuclear Information System (INIS)

    Final reports are presented on work on the following topics: glass technology; enhancement of off-gas aerosol collection; formation and trapping of volatile ruthenium; volatilisation of caesium, technetium and tellurium in high-level waste vitrification; deposition of ruthenium; and calcination of high-level waste liquors. (author)

  2. Aerosol satellite remote sensing

    NARCIS (Netherlands)

    Veefkind, Joris Pepijn

    2001-01-01

    Aerosols are inportant for many processes in the atmosphere. Aerosols are a leading uncertainty in predicting global climate change, To a large extent this uncertainty is caused by a lack of knowledge on the occurrence and concentration of aerosols. On global scale, this information can only be o

  3. Aerosol filtration

    International Nuclear Information System (INIS)

    Significant developments in high efficiency filtration for nuclear applications are reviewed for the period 1968 to 1980. Topics of special interest include factory (bench) and in-place test methods, new developments in paper and filter unit construction methods, vented containment air cleaning systems for LMFBR and light water moderated reactors, and decontamination of offgases from nuclear waste volume reduction processes. It is noted that standards development has been vigorously pursued during this period but that advances in filtration theory have been few. One of the significant changes likely to occur in the immediate future is adoption of the European style of HEPA filters for those that have been in service for the past three decades to obtain the benefits of having almost twice as much filter paper in the same filter cartridge. 71 references

  4. Aerosol Chemistry Between Two Oceans: Auckland’s Urban Aerosol

    Czech Academy of Sciences Publication Activity Database

    Coulson, G.; Olivares, G.; Salmond, J.; Talbot, Nicholas

    -: Italian Aerosol Society, 2015. ISBN N. [European Aerosol Conference EAC 2015. Milano (IT), 06.09.2015-11.09.2015] Institutional support: RVO:67985858 Keywords : urban pollution * aerosol processing * New Zealand Subject RIV: CF - Physical ; Theoretical Chemistry

  5. Sensitivity of aerosol direct radiative forcing to aerosol vertical profile

    OpenAIRE

    Chung, Chul E.; Choi, Jung-Ok

    2014-01-01

    Aerosol vertical profile significantly affects the aerosol direct radiative forcing at the TOA level. The degree to which the aerosol profile impacts the aerosol forcing depends on many factors such as presence of cloud, surface albedo and aerosol single scattering albedo (SSA). Using a radiation model, we show that for absorbing aerosols (with an SSA of 0.7–0.8) whether aerosols are located above cloud or below induces at least one order of magnitude larger changes of the aerosol forcing tha...

  6. Aerosols Science and Technology

    CERN Document Server

    Agranovski, Igor

    2011-01-01

    This self-contained handbook and ready reference examines aerosol science and technology in depth, providing a detailed insight into this progressive field. As such, it covers fundamental concepts, experimental methods, and a wide variety of applications, ranging from aerosol filtration to biological aerosols, and from the synthesis of carbon nanotubes to aerosol reactors.Written by a host of internationally renowned experts in the field, this is an essential resource for chemists and engineers in the chemical and materials disciplines across multiple industries, as well as ideal supplementary

  7. Monthly Averages of Aerosol Properties: A Global Comparison Among Models, Satellite Data, and AERONET Ground Data

    Energy Technology Data Exchange (ETDEWEB)

    Kinne, S.; Lohmann, U; Feichter, J; Schulz, M.; Timmreck, C.; Ghan, Steven J.; Easter, Richard C.; Chin, M; Ginoux, P.; Takemura, T.; Tegen, I.; Koch, D; Herzog, M.; Penner, J.; Pitari, G.; Holben, B. N.; Eck, T.; Smirnov, A.; Dubovik, O.; Slutsker, I.; Tanre, D.; Torres, O.; Mishchenko, M.; Geogdzhayev, I.; Chu, D. A.; Kaufman, Yoram J.

    2003-10-21

    Aerosol introduces the largest uncertainties in model-based estimates of anthropogenic sources on the Earth's climate. A better representation of aerosol in climate models can be expected from an individual processing of aerosol type and new aerosol modules have been developed, that distinguish among at least five aerosol types: sulfate, organic carbon, black carbon, sea-salt and dust. In this study intermediate results of aerosol mass and aerosol optical depth of new aerosol modules from seven global models are evaluated. Among models, differences in predicted mass-fields are expected with differences to initialization and processing. Nonetheless, unusual discrepancies in source strength and in removal rates for particular aerosol types were identified. With simultaneous data for mass and optical depth, type conversion factors were compared. Differences among the tested models cover a factor of 2 for each, even hydrophobic, aerosol type. This is alarming and suggests that efforts of good mass-simulations could be wasted or that conversions are misused to cover for poor mass-simulations. An individual assessment, however, is difficult, as only part of the conversion determining factors (size assumption, permitted humidification and prescribed ambient relative humidity) were revealed. These differences need to be understood and minimized, if conclusions on aerosol processing in models can be drawn from comparisons to aerosol optical depth measurements.

  8. Aerosol in the containment

    International Nuclear Information System (INIS)

    The US program LACE (LWR Aerosol Containment Experiments), in which Italy participates together with several European countries, Canada and Japan, aims at evaluating by means of a large scale experimental activity at HEDL the retention in the pipings and primary container of the radioactive aerosol released following severe accidents in light water reactors. At the same time these experiences will make available data through which the codes used to analyse the behaviour of the aerosol in the containment and to verify whether by means of the codes of thermohydraulic computation it is possible to evaluate with sufficient accuracy variable influencing the aerosol behaviour, can be validated. This report shows and compares the results obtained by the participants in the LACE program with the aerosol containment codes NAVA 5 and CONTAIN for the pre-test computations of the test LA 1, in which an accident called containment by pass is simulated

  9. Sea Spray Aerosols

    DEFF Research Database (Denmark)

    Butcher, Andrew Charles

    Aerosols are important climactically. Their specific emissions are key to reducing the uncertainty in global climate models. Marine aerosols make up the largest source of primary aerosols to the Earth's atmosphere. Uncertainty in marine aerosol mass and number flux lies in separating primary...... emissions produced directly from bubble bursting as the result of air entrainment from breaking waves and particles generated from secondary emissions of volatile organic compounds. In the first paper, we study the chemical properties of particles produced from several sea water proxies with the use of a...... cloud condensation nuclei ounter. Proxy solutions with high inorganic salt concentrations and some organics produce sea spray aerosol particles with little change in cloud condensation activity relative to pure salts. Comparison is made between a frit based method for bubble production and a plunging...

  10. Identification of acephenanthrylene and aceanthrylene in aerosol and its environmental implication

    Institute of Scientific and Technical Information of China (English)

    SHI Quan; WANG TieGuan; ZHONG NingNing; ZHANG ZhiHuan; ZHANG YaHe

    2008-01-01

    Acephenanthrylene and aceanthrylene in aromatic fraction of aerosols were identified by means of online hydrogenation gas chromatography mass spectrometry(GCMS). Compared aerosols from vari-ous sources, acephenanthryiene and aceanthrylene were ubiquitously present in urban aerosol. High concentration of acephenanthrylene and aceanthrylene were found in agricultural biomass and coal combustion particles. However, it is difficult to detect in exhaust from gasoline and diesel engine, dustfall, waste water, soil, and sediment. Combustion emissions were considered the major source of acephenanthrylene and aceanthrylene, which can be used as a potential molecular marker for the source pollution in urban aerosols.

  11. Sugars in Antarctic aerosol

    Science.gov (United States)

    Barbaro, Elena; Kirchgeorg, Torben; Zangrando, Roberta; Vecchiato, Marco; Piazza, Rossano; Barbante, Carlo; Gambaro, Andrea

    2015-10-01

    The processes and transformations occurring in the Antarctic aerosol during atmospheric transport were described using selected sugars as source tracers. Monosaccharides (arabinose, fructose, galactose, glucose, mannose, ribose, xylose), disaccharides (sucrose, lactose, maltose, lactulose), alcohol-sugars (erythritol, mannitol, ribitol, sorbitol, xylitol, maltitol, galactitol) and anhydrosugars (levoglucosan, mannosan and galactosan) were measured in the Antarctic aerosol collected during four different sampling campaigns. For quantification, a sensitive high-pressure anion exchange chromatography was coupled with a single quadrupole mass spectrometer. The method was validated, showing good accuracy and low method quantification limits. This study describes the first determination of sugars in the Antarctic aerosol. The total mean concentration of sugars in the aerosol collected at the "Mario Zucchelli" coastal station was 140 pg m-3; as for the aerosol collected over the Antarctic plateau during two consecutive sampling campaigns, the concentration amounted to 440 and 438 pg m-3. The study of particle-size distribution allowed us to identify the natural emission from spores or from sea-spray as the main sources of sugars in the coastal area. The enrichment of sugars in the fine fraction of the aerosol collected on the Antarctic plateau is due to the degradation of particles during long-range atmospheric transport. The composition of sugars in the coarse fraction was also investigated in the aerosol collected during the oceanographic cruise.

  12. Submicron aerosols: a review

    International Nuclear Information System (INIS)

    Submicron aerosols, ranging in particle diameter from 0.1 μm to 0.001 μm, and in number concentration from 10,000 to 100,000 per cm3, are more or less continuously suspended in the atmosphere we breathe. They usually require in situ measurement of concentration and size distribution with instruments such as diffusion batteries and condensation nucleus counters. Laboratory measurements require the development of submicron aerosol generators. The development of several of these devices and their use in the laboratory and field to measure radioactive as well as inactive aerosols is described

  13. Aerosols from biomass combustion

    Energy Technology Data Exchange (ETDEWEB)

    Nussbaumer, T.

    2001-07-01

    This report is the proceedings of a seminar on biomass combustion and aerosol production organised jointly by the International Energy Agency's (IEA) Task 32 on bio energy and the Swiss Federal Office of Energy (SFOE). This collection of 16 papers discusses the production of aerosols and fine particles by the burning of biomass and their effects. Expert knowledge on the environmental impact of aerosols, formation mechanisms, measurement technologies, methods of analysis and measures to be taken to reduce such emissions is presented. The seminar, visited by 50 participants from 11 countries, shows, according to the authors, that the reduction of aerosol emissions resulting from biomass combustion will remain a challenge for the future.

  14. Sodium oxide aerosol filtration

    International Nuclear Information System (INIS)

    In the scope of the sodium aerosol trapping research effort by the CEA/DSN, the retention capacity and yield were measured for very high efficiency fiberglass filters and several types of prefilters (cyclone agglomerator, fabric prefilters, water scrubbers). (author)

  15. Emergency protection from aerosols

    International Nuclear Information System (INIS)

    Expedient methods were developed that could be used by an average person, using only materials readily available, to protect himself and his family from injury by toxic (e.g., radioactive) aerosols. The most effective means of protection was the use of a household vacuum cleaner to maintain a small positive pressure on a closed house during passage of the aerosol cloud. Protection factors of 800 and above were achieved

  16. Emergency Protection from Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Cristy, G.A.

    2001-11-13

    Expedient methods were developed that could be used by an average person, using only materials readily available, to protect himself and his family from injury by toxic (e.g., radioactive) aerosols. The most effective means of protection was the use of a household vacuum cleaner to maintain a small positive pressure on a closed house during passage of the aerosol cloud. Protection factors of 800 and above were achieved.

  17. MISR Aerosol Typing

    Science.gov (United States)

    Kahn, Ralph A.

    2014-01-01

    AeroCom is an open international initiative of scientists interested in the advancement of the understanding of global aerosol properties and aerosol impacts on climate. A central goal is to more strongly tie and constrain modeling efforts to observational data. A major element for exchanges between data and modeling groups are annual meetings. The meeting was held September 20 through October 2, 1014 and the organizers would like to post the presentations.

  18. Chemical, physical, and optical evolution of biomass burning aerosols: a case study

    Directory of Open Access Journals (Sweden)

    G. Adler

    2010-10-01

    Full Text Available In-situ chemical composition measurements of ambient aerosols have been used for characterizing the evolution of submicron aerosols from a large anthropogenic biomass burning (BB event in Israel. A high resolution Time of Flight Aerosol Mass Spectrometer (Hi-RES-TOF-AMS was used to follow the chemical evolution of BB aerosols during a night-long, extensive nationwide wood burning event and during the following day. While extensive BB is not common in this region, burning of agricultural waste is a common practice. The aging process of the BB aerosols was followed through their chemical, physical and optical properties. Mass spectrometric analysis of the aerosol organic component showed that aerosol aging is characterized by shifting from less oxidized fresh BB aerosols to more oxidized aerosols. Evidence for aerosol aging during the day following the BB event was indicated by an increase in the organic mass, its oxidation state, the total aerosol concentration, and a shift in the modal particle diameter. The effective broadband refractive index (EBRI was derived using a white light optical particle counter (WELAS. The average EBRI for a mixed population of aerosols dominated by open fires was m=1.53(±0.03+0.07i(±0.03, during the smoldering phase of the fires we found the EBRI to be m=1.54(±0.01+0.04i(±0.01 compared to m=1.49(±0.01+0.02i(±0.01 of the aged aerosols during the following day. This change indicates a decrease in the overall aerosol absorption and scattering. Elevated levels of particulate Polycyclic Aromatic Hydrocarbons (PAHs were detected during the entire event, which suggest possible implications for human health during such extensive event.

  19. Chemical, physical, and optical evolution of biomass burning aerosols: a case study

    Science.gov (United States)

    Adler, G.; Flores, J. M.; Abo Riziq, A.; Borrmann, S.; Rudich, Y.

    2011-02-01

    In-situ chemical composition measurements of ambient aerosols have been used for characterizing the evolution of submicron aerosols from a large anthropogenic biomass burning (BB) event in Israel. A high resolution Time of Flight Aerosol Mass Spectrometer (HR-RES-TOF-AMS) was used to follow the chemical evolution of BB aerosols during a night-long, extensive nationwide wood burning event and during the following day. While these types of extensive BB events are not common in this region, burning of agricultural waste is a common practice. The aging process of the BB aerosols was followed through their chemical, physical and optical properties. Mass spectrometric analysis of the aerosol organic component showed that aerosol aging is characterized by shifting from less oxidized fresh BB aerosols to more oxidized aerosols. Evidence for aerosol aging during the day following the BB event was indicated by an increase in the organic mass, its oxidation state, the total aerosol concentration, and a shift in the modal particle diameter. The effective broadband refractive index (EBRI) was derived using a white light optical particle counter (WELAS). The average EBRI for a mixed population of aerosols dominated by open fires was m = 1.53(±0.03) + 0.07i(±0.03), during the smoldering phase of the fires we found the EBRI to be m = 1.54(±0.01) + 0.04i(±0.01) compared to m = 1.49(±0.01) + 0.02i(±0.01) of the aged aerosols during the following day. This change indicates a decrease in the overall aerosol absorption and scattering. Elevated levels of particulate Polycyclic Aromatic Hydrocarbons (PAHs) were detected during the entire event, which suggest possible implications for human health during such extensive event.

  20. Chemical, physical, and optical evolution of biomass burning aerosols: a case study

    Directory of Open Access Journals (Sweden)

    G. Adler

    2011-02-01

    Full Text Available In-situ chemical composition measurements of ambient aerosols have been used for characterizing the evolution of submicron aerosols from a large anthropogenic biomass burning (BB event in Israel. A high resolution Time of Flight Aerosol Mass Spectrometer (HR-RES-TOF-AMS was used to follow the chemical evolution of BB aerosols during a night-long, extensive nationwide wood burning event and during the following day. While these types of extensive BB events are not common in this region, burning of agricultural waste is a common practice. The aging process of the BB aerosols was followed through their chemical, physical and optical properties. Mass spectrometric analysis of the aerosol organic component showed that aerosol aging is characterized by shifting from less oxidized fresh BB aerosols to more oxidized aerosols. Evidence for aerosol aging during the day following the BB event was indicated by an increase in the organic mass, its oxidation state, the total aerosol concentration, and a shift in the modal particle diameter. The effective broadband refractive index (EBRI was derived using a white light optical particle counter (WELAS. The average EBRI for a mixed population of aerosols dominated by open fires was m = 1.53(±0.03 + 0.07i(±0.03, during the smoldering phase of the fires we found the EBRI to be m = 1.54(±0.01 + 0.04i(±0.01 compared to m = 1.49(±0.01 + 0.02i(±0.01 of the aged aerosols during the following day. This change indicates a decrease in the overall aerosol absorption and scattering. Elevated levels of particulate Polycyclic Aromatic Hydrocarbons (PAHs were detected during the entire event, which suggest possible implications for human health during such extensive event.

  1. A multi-model evaluation of aerosols over South Asia: common problems and possible causes

    Science.gov (United States)

    Pan, X.; Chin, M.; Gautam, R.; Bian, H.; Kim, D.; Colarco, P. R.; Diehl, T. L.; Takemura, T.; Pozzoli, L.; Tsigaridis, K.; Bauer, S.; Bellouin, N.

    2015-05-01

    Atmospheric pollution over South Asia attracts special attention due to its effects on regional climate, water cycle and human health. These effects are potentially growing owing to rising trends of anthropogenic aerosol emissions. In this study, the spatio-temporal aerosol distributions over South Asia from seven global aerosol models are evaluated against aerosol retrievals from NASA satellite sensors and ground-based measurements for the period of 2000-2007. Overall, substantial underestimations of aerosol loading over South Asia are found systematically in most model simulations. Averaged over the entire South Asia, the annual mean aerosol optical depth (AOD) is underestimated by a range 15 to 44% across models compared to MISR (Multi-angle Imaging SpectroRadiometer), which is the lowest bound among various satellite AOD retrievals (from MISR, SeaWiFS (Sea-Viewing Wide Field-of-View Sensor), MODIS (Moderate Resolution Imaging Spectroradiometer) Aqua and Terra). In particular during the post-monsoon and wintertime periods (i.e., October-January), when agricultural waste burning and anthropogenic emissions dominate, models fail to capture AOD and aerosol absorption optical depth (AAOD) over the Indo-Gangetic Plain (IGP) compared to ground-based Aerosol Robotic Network (AERONET) sunphotometer measurements. The underestimations of aerosol loading in models generally occur in the lower troposphere (below 2 km) based on the comparisons of aerosol extinction profiles calculated by the models with those from Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) data. Furthermore, surface concentrations of all aerosol components (sulfate, nitrate, organic aerosol (OA) and black carbon (BC)) from the models are found much lower than in situ measurements in winter. Several possible causes for these common problems of underestimating aerosols in models during the post-monsoon and wintertime periods are identified: the aerosol hygroscopic growth and formation of

  2. Physical metrology of aerosols; Metrologie physique des aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Boulaud, D.; Vendel, J. [CEA Saclay, 91 - Gif-sur-Yvette (France). Inst. de Protection et de Surete Nucleaire

    1996-12-31

    The various detection and measuring methods for aerosols are presented, and their selection is related to aerosol characteristics (size range, concentration or mass range), thermo-hydraulic conditions (carrier fluid temperature, pressure and flow rate) and to the measuring system conditions (measuring frequency, data collection speed, cost...). Methods based on aerosol dynamic properties (inertial, diffusional and electrical methods) and aerosol optical properties (localized and integral methods) are described and their performances and applications are compared

  3. Biological aerosol background characterization

    Science.gov (United States)

    Blatny, Janet; Fountain, Augustus W., III

    2011-05-01

    To provide useful information during military operations, or as part of other security situations, a biological aerosol detector has to respond within seconds or minutes to an attack by virulent biological agents, and with low false alarms. Within this time frame, measuring virulence of a known microorganism is extremely difficult, especially if the microorganism is of unknown antigenic or nucleic acid properties. Measuring "live" characteristics of an organism directly is not generally an option, yet only viable organisms are potentially infectious. Fluorescence based instruments have been designed to optically determine if aerosol particles have viability characteristics. Still, such commercially available biological aerosol detection equipment needs to be improved for their use in military and civil applications. Air has an endogenous population of microorganisms that may interfere with alarm software technologies. To design robust algorithms, a comprehensive knowledge of the airborne biological background content is essential. For this reason, there is a need to study ambient live bacterial populations in as many locations as possible. Doing so will permit collection of data to define diverse biological characteristics that in turn can be used to fine tune alarm algorithms. To avoid false alarms, improving software technologies for biological detectors is a crucial feature requiring considerations of various parameters that can be applied to suppress alarm triggers. This NATO Task Group will aim for developing reference methods for monitoring biological aerosol characteristics to improve alarm algorithms for biological detection. Additionally, they will focus on developing reference standard methodology for monitoring biological aerosol characteristics to reduce false alarm rates.

  4. Using the Aerosol Single Scattering Albedo and Angstrom Exponent from AERONET to Determine Aerosol Origins and Mixing States over the Indo-Gangetic Plain

    Science.gov (United States)

    Giles, D. M.; Holben, B. N.; Eck, T. F.; Sinyuk, A.; Slutsker, I.; Smirnov, A.; Schafer, J. S.; Dickerson, R. R.; Thompson, A. M.; Tripathi, S. N.; Singh, R. P.; Ghauri, B.

    2012-12-01

    Aerosol mixtures—whether dominated by dust, carbon, sulfates, nitrates, sea salt, or mixtures of them—complicate the retrieval of remotely sensed aerosol properties from satellites and possibly increase the uncertainty of the aerosol radiative impact on climate. Major aerosol source regions in South Asia include the Thar Desert as well as agricultural lands, Himalayan foothills, and large urban centers in and near the Indo-Gangetic Plain (IGP). Over India and Pakistan, seasonal changes in meteorology, including the monsoon (June-September), significantly affect the transport, lifetime, and type of aerosols. Strong monsoonal winds can promote long range transport of dust resulting in mixtures of dust and carbonaceous aerosols, while more stagnant synoptic conditions (e.g., November-January) can prolong the occurrence of urban/industrial pollution, biomass burning smoke, or mixtures of them over the IGP. Aerosol Robotic Network (AERONET) Sun/sky radiometer data are analyzed to show the aerosol optical depth (AOD) seasonality and aerosol dominant mixing states. The Single Scattering Albedo (SSA) and extinction Angstrom exponent (EAE) relationship has been shown to provide sound clustering of dominant aerosol types using long term AERONET site data near known source regions [Giles et al., 2012]. In this study, aerosol type partitioning using the SSA (440 nm) and EAE (440-870 nm) relationship is further developed to quantify the occurrence of Dust, Mixed (e.g., dust and carbonaceous aerosols), Urban/Industrial (U/I) pollution, and Biomass Burning (BB) smoke. Based on EAE thresholds derived from the cluster analysis (for AOD440nm>0.4), preliminary results (2001-2010) for Kanpur, India, show the overall contributions of each dominant particle type (rounded to the nearest 10%): 10% for Dust (EAE≤0.25), 60% for Mixed (0.251.25). In the IGP, BB aerosols may have varying sizes (e.g., corresponding to 1.2agricultural waste, forest, or dung burning), combustion phases, or

  5. Nuclear Aerosols: Direct Simulation and Elucidation of the Role of Multiple Components, Radioactivity, Charge, Shape and Spatial Inhomogeneity

    International Nuclear Information System (INIS)

    Nuclear aerosols can originate from severe core damage in light water reactors, core disruptive accidents in fast reactors, nuclear accidents during nuclear material transport, at waste disposal sites, or explosions. These aerosols evolve under natural transport processes as well as under the influence of engineered safety features. Such aerosols can be hazardous for the equipment inside the reactor, and when leaked into the environment, pose potential risks to the public. Hence, the origin, movement and distribution of these aerosols need to be studied and controlled

  6. Improving Aerosol Simulation over South Asia for Climate and Air Quality Studies

    Science.gov (United States)

    Pan, Xiaohua; Chin, Mian; Bian, Huisheng; Gautam, Ritesh

    2014-01-01

    Atmospheric pollution over South Asia attracts special attention due to its effects on regional climate, the water cycle, and human health. These effects are potentially growing owing to rising trends of anthropogenic aerosol emissions found there. However, it has been proved quite challenging to adequately represent the aerosol spatial distribution and magnitude over this critical region in global models (Pan et al. 2014), with the surface concentrations, aerosol optical depth (AOD), and absorbing AOD (AAOD) significantly underestimated, especially in October-January when the agricultural waste burning and anthropogenic aerosol dominate over dust aerosol. In this study, we aim to investigate the causes for such discrepancy in winter by conducting sets of model experiments with NASA's GEOS-5 in terms of (1) spatial resolution, (2) emission amount, and (3) meteorological fields.

  7. Distribution of Aerosol During Diwali Festival in the Recent Decade over India

    Science.gov (United States)

    Gouda, K. C.; Bhat, N.; Goswami, P.

    2012-12-01

    Diwali is a very famous festival in India during which people play with crackers and fireworks. Due to burning of crackers and fireworks, the concentration of anthropogenic aerosol increases in the atmosphere. In the present work the temporal and spatial variation of atmospheric aerosol parameters like Aerosol Optical Thickness (AOT), Aerosol Depth (AOD), TWC, Aerosol Particle size etc. are analyzed using the high resolution satellite data from different sources. 10 year Climatology of the Aerosol over India is generated using the data before, after and during Diwali festival time for the period of 2002 to 2011. The three climatologies show different distribution of the aerosol parameters through out the country. The northern and eastern part shows more rich in the aerosol during the festival. To understand the temporal variability, analysis of aerosol properties are being carried out one week before the festival day and one week after the festival day and compared with the day of festival for all the years. It is observed that the AOD increases from the preceding days of the festival since people start playing with crackers and fireworks about two days prior to the main Diwali day especially in North India. It is also observed from the present study that during the Diwali month the aerosol parameters are maximum in Northern part of India which supports the practice of higher incidences of bio-mass burning and residues of waste agricultural crop's fire activities. Ten year (2002-2011) average distribution of MODIS derived Aerosol Optical Thickness (AOT) during Diwali over India is presented in figure 1. A complete evaluation of distribution of AOT, AOD, TWC, Rainfall, suspended particulate Material etc. along with statistical analysis are also presented in this work. Figure 1: Ten year (2002-2011) average distribution of MODIS derived Aerosol Optical Thickness (AOT) during Diwali over India

  8. Aerosol climatology over Nile Delta based on MODIS, MISR and OMI satellite data

    OpenAIRE

    H. S. Marey; J. C. Gille; H. M. El-Askary; Shalaby, E. A.; M. E. El-Raey

    2011-01-01

    Since 1999 Cairo and the Nile delta region have suffered from air pollution episodes called the "black cloud" during the fall season. These have been attributed to either burning of agriculture waste or long-range transport of desert dust. Here we present a detailed analysis of the optical and microphysical aerosol properties, based on satellite data. Monthly mean values of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD) at 550 nm were examined for the 10 yr ...

  9. EMSP Final Report: Electrically Driven Technologies for Radioactive Aerosol Abatement

    Energy Technology Data Exchange (ETDEWEB)

    DePaoli, D.W.

    2003-01-22

    The purpose of this research project was to develop an improved understanding of how electrically driven processes, including electrocoalescence, acoustic agglomeration, and electric filtration, may be employed to efficiently treat problems caused by the formation of aerosols during DOE waste treatment operations. The production of aerosols during treatment and retrieval operations in radioactive waste tanks and during thermal treatment operations such as calcination presents a significant problem of cost, worker exposure, potential for release, and increased waste volume. There was anecdotal evidence in the literature that acoustic agglomeration and electrical coalescence could be used together to change the size distribution of aerosol particles in such a way as to promote easier filtration and less frequent maintenance of filtration systems. As such, those electrically driven technologies could potentially be used as remote technologies for improved treatment; however, existing theoretical models are not suitable for prediction and design. To investigate the physics of such systems, and also to prototype a system for such processes, a collaborative project was undertaken between Oak Ridge National Laboratory (ORNL) and the University of Texas at Austin (UT). ORNL was responsible for the larger-scale prototyping portion of the project, while UT was primarily responsible for the detailed physics in smaller scale unit reactors. It was found that both electrical coalescence and acoustic agglomeration do in fact increase the rate of aggregation of aerosols. Electrical coalescence requires significantly less input power than acoustic agglomeration, but it is much less effective in its ability to aggregate/coalesce aerosols. The larger-scale prototype showed qualitatively similar results as the unit reactor tests, but presented more difficulty in interpretation of the results because of the complex multi-physics coupling that necessarily occur in all larger

  10. Determination of Elemental Concentrations in Atmospheric Aerosol in Tirana by Energy-dispersive X-Ray Fluorescence Spectrometry

    International Nuclear Information System (INIS)

    In the period between March and May 1998, fifty aerosol samples were collected in two stations in the city of Tirana. The first station was situated at the urban area, while the second one was near the Centre of the city. The total aerosol samples were collected in TFA-$1 filters using high volume pumps. An experimental EDXRF instrument was used for the determination of the concentrations of 15 elements in the loaded aerosol filters. The analytical data obtained, allowed the calculation of the mean elemental concentrations in the aerosol and their crustal enrichment factors. The applications in the aerosol and their crustal enrichment factors. The application of multivariate methods (Factor Analysis) allowed the identification of the main aerosol sources. Along with the soil dust and sea salt particles, which are the main natural sources, there are clearly identified two other anthropogenic sources related with oil combustion and waste incineration.(authors)

  11. Seasonal variability in the optical properties of Baltic aerosols

    Directory of Open Access Journals (Sweden)

    Agnieszka Zdun

    2011-03-01

    Full Text Available A five-year dataset of spectral aerosol optical thickness was used to analyse the seasonal variability of aerosol optical properties (the aerosol opticalthickness (AOT at wavelength λ=500 nm, AOT(500 and the Ångström exponent for the 440-870 nm spectral range,α(440, 870 over the Baltic Sea and dependence of these optical properties on meteorological factors (wind direction, wind speed and relativehumidity. The data from the Gotland station of the global radiometric network AERONET (Aerosol Robotic Network, http://aeronet.gsfc.nasa.govwere taken to be representative of the Baltic Sea conditions. Meteorological observations from Fårosund were also analysed.       Analysis of the data from 1999 to 2003 revealed a strong seasonal cycle in AOT(500 and α(440, 870. Two maxima of monthly mean values of AOT(500over the Baltic were observed. In April, an increase in the monthly mean aerosol optical thickness over Gotland most probably resulted from agricultural waste strawburning, mainly in northern Europe and Russia as well as in the Baltic states, Ukraine and Belarus. During July and August, the aerosol optical thickness wasaffected by uncontrolled fires (biomass burning. There was a local minimum of AOT(500 in June.       Wind direction, a local meteorological parameter strongly related to air mass advection, is the main meteorological factor influencing the variabilityof aerosol optical properties in each season. The highest mean values of AOT(500 and α(440, 870 occurred with easterly winds in both spring and summer,but with southerly winds in autumn.

  12. Graphical aerosol classification method using aerosol relative optical depth

    Science.gov (United States)

    Chen, Qi-Xiang; Yuan, Yuan; Shuai, Yong; Tan, He-Ping

    2016-06-01

    A simple graphical method is presented to classify aerosol types based on a combination of aerosol optical thickness (AOT) and aerosol relative optical thickness (AROT). Six aerosol types, including maritime (MA), desert dust (DD), continental (CO), sub-continental (SC), urban industry (UI) and biomass burning (BB), are discriminated in a two dimensional space of AOT440 and AROT1020/440. Numerical calculations are performed using MIE theory based on a multi log-normal particle size distribution, and the AROT ranges for each aerosol type are determined. More than 5 years of daily observations from 8 representative aerosol sites are applied to the method to confirm spatial applicability. Finally, 3 individual cases are analyzed according to their specific aerosol status. The outcomes indicate that the new graphical method coordinates well with regional characteristics and is also able to distinguish aerosol variations in individual situations. This technique demonstrates a novel way to estimate different aerosol types and provide information on radiative forcing calculations and satellite data corrections.

  13. Aerosol samplers innovation possibilities

    International Nuclear Information System (INIS)

    The growing demand for an early detection of increased levels of the artificial radionuclides in the atmosphere resulted in the design and fabrication of an aerosol sampler with automated spectrometric unit providing online gamma spectrometry above the aerosol filter. Study was performed with two types of high volume samplers- SENYA JL-900 SnowWhite (900 m3/h) a SENYA JL-150 Hunter (150 m3/h). This work gives results of the design optimization with respect to the detector type, geometry of measurement, remote control and spectrometric evaluation 222Rn and 220Rn concentration fluctuations in the outdoor air are discussed with regard to the detection limit so the radionuclides expected after the NPP accident. (authors)

  14. An aerosol sampler

    International Nuclear Information System (INIS)

    That device is characterized in that, within a closed casing provided with a sealable opening, it comprises a storage rack for a plurality of stacked saucers, a sheath having a transverse slot for extracting said saucers separately from, or re-introducing same into, their respective sockets, a transfer gripping-member with its control mechanism for taking saucers from their respective sockets through said slot and moving them transversally, a sealing-plate mounted below the casing-opening, said plate being associated with a pushing mechanism, and a laterally retractable cover controlled by a separate mechanism for unsealing said casing opening and collecting aerosols on a saucer. That device can be used for taking samples of sodium aerosols

  15. Aerosol Observing System (AOS) Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Jefferson, A

    2011-01-17

    The Aerosol Observing System (AOS) is a suite of in situ surface measurements of aerosol optical and cloud-forming properties. The instruments measure aerosol properties that influence the earth’s radiative balance. The primary optical measurements are those of the aerosol scattering and absorption coefficients as a function of particle size and radiation wavelength and cloud condensation nuclei (CCN) measurements as a function of percent supersaturation. Additional measurements include those of the particle number concentration and scattering hygroscopic growth. Aerosol optical measurements are useful for calculating parameters used in radiative forcing calculations such as the aerosol single-scattering albedo, asymmetry parameter, mass scattering efficiency, and hygroscopic growth. CCN measurements are important in cloud microphysical models to predict droplet formation.

  16. Aerosol characterization during project POLINAT

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, D.E.; Hopkins, A.R.; Paladino, J.D.; Whitefield, P.D. [Missouri Univ., Rolla, MO (United States). Cloud and Aerosol Sciences Lab.; Lilenfeld, H.V. [McDonnell Douglas Aerospace-East, St. Louis, MO (United States)

    1997-12-31

    The objectives of the aerosol/particulate characterization measurements of project POLINAT (POLlution from aircraft emissions In the North ATlantic flight corridor) are: to search for aerosol/particulate signatures of air traffic emissions in the region of the North Atlantic Flight Corridor; to search for the aerosol/particulate component of large scale enhancement (`corridor effects`) of air traffic related species in the North Atlantic region; to determine the effective emission indices for the aerosol/particulate component of engine exhaust in both the near and far field of aircraft exhaust plumes; to measure the dispersion and transformation of the aerosol/particulate component of aircraft emissions as a function of ambient condition; to characterize background levels of aerosol/particulate concentrations in the North Atlantic Region; and to determine effective emission indices for engine exhaust particulates for regimes beyond the jet phase of plume expansion. (author) 10 refs.

  17. Dust and atmospheric aerosol

    International Nuclear Information System (INIS)

    The paper describes the types and characteristics of the various aerosol particles (by size effects, and origin) and goes on to discuss the composition of particulates and their variation in different places in Asia, and the origin of global particulate emissions from natural and anthropogenic sources. The effects of particulate matter on human health, visibility and climate are summarised. Techniques for control and abatement of particulate emissions are outlined. 10 refs., 4 figs., 11 tabs

  18. Photothermal spectroscopy of aerosols

    International Nuclear Information System (INIS)

    In situ aerosol absorption spectroscopy was performed using two novel photothermal detection schemes. The first, based on a photorefractive effect and coherent detection, called phase fluctuation optical heterodyne (PFLOH) spectroscopy, could, depending on the geometry employed, yield particle specific or particle and gas absorption data. Single particles of graphite as small as 1 μm were detected in the particle specific mode. In another geometrical configuration, the total absorption (both gas and particle) of submicron sized aerosols of ammonium sulfate particles in equilibrium with gaseous ammonia and water vapor were measured at varying CO2 laser frequencies. The specific absorption coefficient for the sulfate ion was measured to be 0.5 m2/g at 1087 cm-1. The absorption coefficient sensitivity of this scheme was less than or equal to 10-8 cm-1. The second scheme is a hybrid visible Mie scattering scheme incorporating photothermal modulation. Particle specific data on ammonium sulfate droplets were obtained. For chemically identical species, the relative absorption spectrum versus laser frequency can be obtained for polydisperse aerosol distributions directly from the data without the need for complex inverse scattering calculations

  19. Aerosol influence on radiative cooling

    OpenAIRE

    Grassl, Hartmut

    2011-01-01

    Aerosol particles have a complex index of refraction and therefore contribute to atmospheric emission and radiative cooling rates. In this paper calculations of the longwave flux divergence within the atmosphere at different heights are presented including water vapour and aerosol particles as emitters and absorbers. The spectral region covered is 5 to 100 microns divided into 23 spectral intervals. The relevant properties of the aerosol particles, the single scattering albedo and the extinct...

  20. Wastes options

    International Nuclear Information System (INIS)

    After a description of the EEC environmental policy, some wastes families are described: bio-contaminant wastes (municipal and industrial), hospitals wastes, toxic wastes in dispersed quantities, nuclear wastes (radioactive and thermal), plastics compounds wastes, volatiles organic compounds, hydrocarbons and used solvents. Sources, quantities and treatments are given. (A.B.). refs., figs., tabs

  1. Connecting Water Quality With Air Quality Through Microbial Aerosols

    Science.gov (United States)

    Dueker, M. Elias

    air by increasing microbial aerosol settling rates and enhancing viability of aerosolized marine microbes. Using methods developed for the non-urban site, the role of local environment and winds in mediating water-air connections was further investigated in the urban environment. The local environment, including water surfaces, was an important source of microbial aerosols at urban sites. Large portions of the urban waterfront microbial aerosol communities were aquatic and, at a highly polluted Superfund waterfront, were closely related to bacteria previously described in environments contaminated with hydrocarbons, heavy metals, sewage and other industrial waste. Culturable urban aerosols and surface waters contained bacterial genera known to include human pathogens and asthma agents. High onshore winds strengthened this water-air connection by playing both a transport and production role. The microbial connection between water and air quality outlined by this dissertation highlights the need for information on the mechanisms that deliver surface water materials to terrestrial systems on a much larger scale. Moving from point measurements to landscape-level analyses will allow for the quantitative assessment of implications for this microbial water-air-land transfer in both urban and non-urban arenas.

  2. Topics in current aerosol research

    CERN Document Server

    Hidy, G M

    1971-01-01

    Topics in Current Aerosol Research deals with the fundamental aspects of aerosol science, with emphasis on experiment and theory describing highly dispersed aerosols (HDAs) as well as the dynamics of charged suspensions. Topics covered range from the basic properties of HDAs to their formation and methods of generation; sources of electric charges; interactions between fluid and aerosol particles; and one-dimensional motion of charged cloud of particles. This volume is comprised of 13 chapters and begins with an introduction to the basic properties of HDAs, followed by a discussion on the form

  3. Nuclear aerosol test facility studies using plasma torch aerosol generator

    International Nuclear Information System (INIS)

    In order to study the behavior of aerosols released into the reactor containment following accidents, an experimental simulation facility, called Nuclear Aerosol Test Facility (NATF) has recently been built and commissioned in BARC. It mainly consists of a Test vessel for simulating the containment, plasma torch aerosol generator (PTAG) system for generating metal-based aerosols and aerosol monitoring instrumentation. The main component of the PTAG is a 40 kW dc plasma torch, powered by a constant current power supply, operating in a non-transferred arc mode. Optimal operating conditions of PTAG have been established. Experiments consist of injecting the aerosols of a given material for about 20 minutes into the vessel, simultaneously monitoring the concentrations at various points in the vessel. The measurements of the size distribution and mass concentrations in the vessel are carried out at periodic intervals. Various combination of experiments with different metals such as zinc, tin and manganese, under varying turbulence conditions (with and without keeping the fan continuously on) have been performed. The aerosols were generally found to be fractal aggregates with low fractal dimension (∼1.6). The mass depletion data have been subjected to theoretical analysis and validation exercises with available aerosol behavior codes. The results are further discussed. (author)

  4. 城市固体废弃物综合处理厂微生物气溶胶污染特性%Characteristics of microbial aerosol pollution in urban solid waste comprehensive treatment plant

    Institute of Scientific and Technical Information of China (English)

    张俊超; 刘建伟; 马文林; 刘宾; 赵玉柱; 吉恒

    2012-01-01

    A study was conducted to assess the degree of airborne microbial contamination generated by a urban solid waste comprehensive treatment plant, the domestic waste pretreatment area, kitchen waste pretreat- ment area, fecal waste pretreatment area and the joint anaerobic area of a urban solid waste comprehensive treat- ment plant in Erdos were chosen as research objects. The results show that there are significant statistical differ- ences in concentration of airborne bacteria and fungi are detected between air samples collected from different function areas (p 〈 0.05) , their highest concentration are typically determined in domestic waste aggregate room. According to evaluation criterion of airborne microorganism find that heterotrophic bacteria and fungi in different function areas have different degrees of pollution. Particle size analysis show that heterotrophic bacteria in different function areas mainly concentrate in the stage 1, stage 2, stage 3 and stage 4, and the fungi mainly concentrate in the stage 3 and stage 4 in different function areas, there are no significant differences (p 〉0.05) between the different function areas for both heterotrophic bacteria and fungi.%以鄂尔多斯市某城市固体废弃物综合处理厂的生活垃圾预处理区、餐厨预处理区、粪便预处理区及联合厌氧发酵区为对象,研究不同功能区的微生物气溶胶污染特性。研究结果表明,不同功能区空气异养细菌和真菌的浓度存在显著性差异(p〈0.05),尤以生活垃圾集料间产生的异养细菌和真菌浓度最高。对照空气微生物评价标准,不同功能区产生的异养细菌和真菌大都有不同程度的污染。粒径分析表明,不同功能区异养细菌粒径主要集中在第1、2、3、4级,各功能区之间无显著性差异(p〉0.05),与细菌粒径分布不同,不同功能区真菌粒径主要分布在第3级和第4级,也无明显差异(p〉0.05)。

  5. Solid waste

    International Nuclear Information System (INIS)

    The article drawn up within the framework of 'the assessment of the state of the environment in Lebanon' provides an overview of solid waste management, and assesses future wastes volume and waste disposal issues.In particular it addresses the following concerns: - Long term projections of solid waste arisings (i.e. domestic, industrial, such commercial wastes, vehicle types, construction waste, waste oils, hazardous toxic wastes and finally hospital and clinical wastes) are described. - Appropriate disposal routes, and strategies for reducing volumes for final disposal - Balance between municipal and industrial solid waste generation and disposal/treatment and - environmental impacts (aesthetics, human health, natural environment )of existing dumps, and the potential impact of government plans for construction of solid waste facilities). Possible policies for institutional reform within the waste management sector are proposed. Tables provides estimations of generation rates and distribution of wastes in different regions of Lebanon. Laws related to solid waste management are summarized

  6. Waste management

    OpenAIRE

    Knopová Policarová, Táňa

    2014-01-01

    Diploma thesis deals with waste disposal in the Czech Republic, including waste production and waste recovery. The aim of this work is to characterize and evaluate the waste production, sorting a disposal in the Czech Republic. Theoretical basis of diploma thesis are focused on basic concepts of waste management legislation, the generation of waste and how to prevent the formation or at least reduce it. The greatest attention is paid to waste disposal, in which there are presented and analyze...

  7. Aerosol extinction in coastal zone

    NARCIS (Netherlands)

    Piazzola, J.; Kaloshin, G.; Leeuw, G. de; Eijk, A.M.J. van

    2004-01-01

    The performance of electro-optical systems can be substantially affected by aerosol particles that scatter and absorb electromagnetic radiation. A few years ago, an empirical model was developed describing the aerosol size distributions in the Mediterranean coastal atmosphere near Toulon (France). T

  8. Aerosol therapy in young children

    NARCIS (Netherlands)

    H.M. Janssens (Hettie)

    2001-01-01

    textabstractInhalation of aerosolized drugs has become an established means for treatment of pulmonary diseases in the last fifiy years. The majoriry of aerosol therapy in childhood concerns inhaled corticosteroids and bronchodilators in the management of asthma. Administration of drugs via the inha

  9. Correlation for aerosol sedimentation

    International Nuclear Information System (INIS)

    The fission product source term from a postulated light water reactor (LWR) accident has several components. One of these components is the suspended aerosols present in the atmosphere during containment degradation and failure. Sedimentation, inertial impaction, and Stefan-Nusselt flows are the dominant natural removal mechanisms in the containment atmosphere for the majority of the postulated LWR severe accidents. The sedimentation correlation described was developed for conditions applicable to the primary coolant system and containment under severe accident conditions. The correlation exists as a result of a unique nondimensional mass concentration versus nondimensional particle volume

  10. Aerosols indirectly warm the Arctic

    Directory of Open Access Journals (Sweden)

    T. Mauritsen

    2010-07-01

    Full Text Available On average, airborne aerosol particles cool the Earth's surface directly by absorbing and scattering sunlight and indirectly by influencing cloud reflectivity, life time, thickness or extent. Here we show that over the central Arctic Ocean, where there is frequently a lack of aerosol particles upon which clouds may form, a small increase in aerosol loading may enhance cloudiness thereby likely causing a climatologically significant warming at the ice-covered Arctic surface. Under these low concentration conditions cloud droplets grow to drizzle sizes and fall, even in the absence of collisions and coalescence, thereby diminishing cloud water. Evidence from a case study suggests that interactions between aerosol, clouds and precipitation could be responsible for attaining the observed low aerosol concentrations.

  11. An Indigenously Developed Insecticidal Aerosol

    Directory of Open Access Journals (Sweden)

    R. N. Varma

    1969-10-01

    Full Text Available A total of 6 "Test" insecticidal aerosols (TA-I to VI indigenously produced were tested during the years 1966-67 as suitable replacements for imported aerosols.TA-I produced deep yellow staining and a yellowish spray mist. Its capacity was only 120 ml fluid. TA-III types II and III containing modified aerosol formulation with "Esso solvent 3245" and mineral turpentine oil (Burmah Shelland Freon 12 11 (all indigenouswere comparable to he "SRA" in insecticidial efficacy. The container was also manufactured in the country and it compared well with the "SRA" in construction, resistance against rough usage and mechanical function. They were both finally approved for introduction in the services as replacement for imported aerosols. TA-IV performed well in inscticidial assessment, but the aerosols formulation. TA-V and VI were similar to TA-III types II and III respectively.

  12. Residential Waste

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Fruergaard, Thilde; Matsufuji, Y.

    2011-01-01

    are discussed in this chapter. Characterizing residential waste is faced with the problem that many residences already divert some waste away from the official collection systems, for example performing home composting of vegetable waste and garden waste, having their bundled newspaper picked up by......Residential waste comes from residential areas with multi-family and single-family housing and includes four types of waste: household waste, garden waste, bulky waste and household hazardous waste. Typical unit generation rates, material composition, chemical composition and determining factors...... the scouts twice a year or bringing their used furniture to the flea markets organized by charity clubs. Thus, much of the data available on residential waste represents collected waste and not necessarily all generated waste. The latter can only be characterized by careful studies directly at the...

  13. Residential Waste

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Fruergaard, Thilde; Matsufuji, Y.

    2011-01-01

    Residential waste comes from residential areas with multi-family and single-family housing and includes four types of waste: household waste, garden waste, bulky waste and household hazardous waste. Typical unit generation rates, material composition, chemical composition and determining factors...... are discussed in this chapter. Characterizing residential waste is faced with the problem that many residences already divert some waste away from the official collection systems, for example performing home composting of vegetable waste and garden waste, having their bundled newspaper picked up by...... the scouts twice a year or bringing their used furniture to the flea markets organized by charity clubs. Thus, much of the data available on residential waste represents collected waste and not necessarily all generated waste. The latter can only be characterized by careful studies directly at the...

  14. Global aerosol transport and consequences for the radiation budget

    International Nuclear Information System (INIS)

    Man's activities may influence global climate by changing the atmospheric composition and surface characteristics and by waste heat. Most prominent within this discussion is the increase or decrease of radiatively active trace gases like CO/sub 2/, N/sub 2/O, O/sub 3/, and others. The general opinion is converging towards a greenhouse effect as a combined action of all trace gases, whose exact magnitude is uncertain mainly because of the unknown reaction of water cycle. The aim of our global 2-D (resolving latitude and height) aerosol transport model is the calculation of aerosol particle number density profiles as a function of latitude for present natural plus anthropogenic emissions. The aerosol transport model uses prescribed meridonal circulation, diffusivity factors and cloud climatology for January as well as July. All these latitude and height dependent input parameters were taken from well known sources. The fixed climatology excludes the feedback of aerosol particle parameter changes on mean circulation. However, the radiative parameters of six clouds types are modified, although they possess by adoption of the Telegadas and London (1954) cloud climatology prescribed amount and height. The inclusion of the feedback on mean circulation seems premature at present. Adding particles either accounting for natural emissions or natural anthropogenic emission and removing particles by all known sinks outside and within clouds gives us - for the stationary state - vertical profiles of aerosol number density in three sizes classes as a function of latitude. These profiles in turn are input for radiation flux calculations in clear and cloudy areas in order to assess net flux changes caused by the present aerosol load in comparison to a scenario without anthropogenic emissions. The net flux changes finally are compared to those calculated for increased CO/sub 2/ levels

  15. Atmospheric and aerosol chemistry

    International Nuclear Information System (INIS)

    This series presents critical reviews of the present position and future trends in modern chemical research. Short and concise reports on chemistry, each written by the world renowned experts. Still valid and useful after 5 or 10 years. More information as well as the electronic version of the whole content available at: springerlink.com. Christian George, Barbara D'Anna, Hartmut Herrmann, Christian Weller, Veronica Vaida, D. J. Donaldson, Thorsten Bartels-Rausch, Markus Ammann Emerging Areas in Atmospheric Photochemistry. Lisa Whalley, Daniel Stone, Dwayne Heard New Insights into the Tropospheric Oxidation of Isoprene: Combining Field Measurements, Laboratory Studies, Chemical Modelling and Quantum Theory. Neil M. Donahue, Allen L. Robinson, Erica R. Trump, Ilona Riipinen, Jesse H. Kroll Volatility and Aging of Atmospheric Organic Aerosol. P. A. Ariya, G. Kos, R. Mortazavi, E. D. Hudson, V. Kanthasamy, N. Eltouny, J. Sun, C. Wilde Bio-Organic Materials in the Atmosphere and Snow: Measurement and Characterization V. Faye McNeill, Neha Sareen, Allison N. Schwier Surface-Active Organics in Atmospheric Aerosols.

  16. INVESTIGATION ON CONTAMINATION OF MICROORGANISM AEROSOL IN SORTING SITES OF IMPORTED WASTE%进口废旧物品分拣场微生物气溶胶污染状况调查

    Institute of Scientific and Technical Information of China (English)

    李金有; 李西标; 王林; 陈春田; 程晶晶; 张顺合; 慈颖; 郭文静; 潘沪林

    2013-01-01

    Objective To investigate the microbiological contamination of bioaerosol released in sorting sites of import waste. Methods The sampling method by percussion sampler of six - level sieves and culture isolation and identification methods were used to do on - site monitoring. Results Total number of bacteria and fungi sampled in sorting sites were higher than that in control group. More than thirty kinds of bacteria including Streptococcus pneumoniae were detected in sorting sites. Conclusion The microbial contamination in atmospheric bioaerosol released in sorting sites of import waste is beyond the standard, and the pathogenic microorganisms exist. So the infection risks exist for employees.%目的 了解进口废旧物品分拣场所气溶胶中微生物的污染状况.方法 以六级筛孔撞击式采样器采样与培养分离鉴定方法,进行了现场监测.结果 进口废旧物品分拣场所气溶胶中细菌总数和霉菌总数均高于其他场所.检出包括肺炎链球菌在内的30余种细菌.结论 进口废旧物品分拣场所气溶胶中微生物污染超标,存在致病微生物,对从业人员存在感染的危险性.

  17. The GRAPE aerosol retrieval algorithm

    Directory of Open Access Journals (Sweden)

    G. E. Thomas

    2009-11-01

    Full Text Available The aerosol component of the Oxford-Rutherford Aerosol and Cloud (ORAC combined cloud and aerosol retrieval scheme is described and the theoretical performance of the algorithm is analysed. ORAC is an optimal estimation retrieval scheme for deriving cloud and aerosol properties from measurements made by imaging satellite radiometers and, when applied to cloud free radiances, provides estimates of aerosol optical depth at a wavelength of 550 nm, aerosol effective radius and surface reflectance at 550 nm. The aerosol retrieval component of ORAC has several incarnations – this paper addresses the version which operates in conjunction with the cloud retrieval component of ORAC (described by Watts et al., 1998, as applied in producing the Global Retrieval of ATSR Cloud Parameters and Evaluation (GRAPE data-set.

    The algorithm is described in detail and its performance examined. This includes a discussion of errors resulting from the formulation of the forward model, sensitivity of the retrieval to the measurements and a priori constraints, and errors resulting from assumptions made about the atmospheric/surface state.

  18. Aerosol entrainment from a sparged non-Newtonian slurry.

    Science.gov (United States)

    Fritz, Brad G

    2006-08-01

    Previous bench-scale experiments have provided data necessary for the development of empirical models that describe aerosol entrainment from bubble bursting. However, previous work has not been extended to non-Newtonian liquid slurries. Design of a waste treatment plant on the Hanford Site in Washington required an evaluation of the applicability of these models outside of their intended range. For this evaluation, aerosol measurements were conducted above an air-sparged mixing tank filled with simulated waste slurry possessing Bingham plastic rheological properties. Three aerosol-size fractions were measured at three sampling heights and for three different sparging rates. The measured entrainment was compared with entrainment models. One model developed based on bench-scale air-water experiments agreed well with measured entrainment. Another model did not agree well with the measured entrainment. It appeared that the source of discrepancy between measured and modeled entrainment stemmed from application beyond the range of data used to develop the model. A possible separation in entrainment coefficients between air-water and steam-water systems was identified. A third entrainment model was adapted to match experimental conditions and fit a posteri to the experimental data, resulting in a modified version that resulted in estimated entrainment rates similar to the first model. PMID:16933643

  19. Research on aerosol formation, aerosol behaviour, aerosol filtration, aerosol measurement techniques and sodium fires at the Laboratory for Aerosol Physics and Filter Technology at the Nuclear Research Center Karlsruhe

    International Nuclear Information System (INIS)

    The behaviour of aerosols in LMFBR plant systems is of great importance for a number of problems, both normal operational and accident kind. This paper covers the following: aerosol modelling for LMFBR containment systems; aerosol size spectrometry by laser light scattering; experimental facilities and experimental results concerned with aerosol release under accident conditions; filtration of sodium oxide aerosols by multilayer sand bed filters

  20. Shipborne aerosol IR decoy modulated by laser

    Institute of Scientific and Technical Information of China (English)

    叶晓英; 吴刚; 邓盼; 范宁

    2004-01-01

    Working principles, features, current situation and future development of the aerosol IR decoys are summarized in this paper, and a new type aerosol IR decoy aerosol IR decoy modulated by laser is emphasized. The simulation results show that compared with the traditional IR decoys, the late-model aerosol IR decoy effectively enhances the capability of protecting targets and countermining IR guidance weapons. It is a new direction of aerosol IR decoys.

  1. Effect of aerosolization on subsequent bacterial survival.

    OpenAIRE

    Walter, M V; Marthi, B; Fieland, V P; Ganio, L M

    1990-01-01

    To determine whether aerosolization could impair bacterial survival, Pseudomonas syringae and Erwinia herbicola were aerosolized in a greenhouse, the aerosol was sampled at various distances from the site of release by using all-glass impingers, and bacterial survival was followed in the impingers for 6 h. Bacterial survival subsequent to aerosolization of P. syringae and E. herbicola was not impaired 1 m from the site of release. P. syringae aerosolized at 3 to 15 m from the site of release ...

  2. A fixed frequency aerosol albedometer.

    Science.gov (United States)

    Thompson, Jonathan E; Barta, Nick; Policarpio, Danielle; Duvall, Richard

    2008-02-01

    A new method for the measurement of aerosol single scatter albedo (omega) at 532 nm was developed. The method employs cavity ring-down spectroscopy (CRDS) for measurement of aerosol extinction coefficient (b(ext)) and an integrating sphere nephelometer for determination of aerosol scattering coefficient (b(scat)). A unique feature of this method is that the extinction and scattering measurements are conducted simultaneously, on the exact same sample volume. Limits of detection (3s) for the extinction and scattering channel were 0.61 Mm(-1) and 2.7 Mm(-1) respectively. PMID:18542299

  3. Instrumentation for tropospheric aerosol characterization

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Z.; Young, S.E.; Becker, C.H.; Coggiola, M.J. [SRI International, Menlo Park, CA (United States); Wollnik, H. [Giessen Univ. (Germany)

    1997-12-31

    A new instrument has been developed that determines the abundance, size distribution, and chemical composition of tropospheric and lower stratospheric aerosols with diameters down to 0.2 {mu}m. In addition to aerosol characterization, the instrument also monitors the chemical composition of the ambient gas. More than 25.000 aerosol particle mass spectra were recorded during the NASA-sponsored Subsonic Aircraft: Contrail and Cloud Effects Special Study (SUCCESS) field program using NASA`s DC-8 research aircraft. (author) 7 refs.

  4. eDPS Aerosol Collection

    Energy Technology Data Exchange (ETDEWEB)

    Venzie, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-10-13

    The eDPS Aerosol Collection project studies the fundamental physics of electrostatic aerosol collection for national security applications. The interpretation of aerosol data requires understanding and correcting for biases introduced from particle genesis through collection and analysis. The research and development undertaken in this project provides the basis for both the statistical correction of existing equipment and techniques; as well as, the development of new collectors and analytical techniques designed to minimize unwanted biases while improving the efficiency of locating and measuring individual particles of interest.

  5. Aerosol growth in Titan's ionosphere.

    Science.gov (United States)

    Lavvas, Panayotis; Yelle, Roger V; Koskinen, Tommi; Bazin, Axel; Vuitton, Véronique; Vigren, Erik; Galand, Marina; Wellbrock, Anne; Coates, Andrew J; Wahlund, Jan-Erik; Crary, Frank J; Snowden, Darci

    2013-02-19

    Photochemically produced aerosols are common among the atmospheres of our solar system and beyond. Observations and models have shown that photochemical aerosols have direct consequences on atmospheric properties as well as important astrobiological ramifications, but the mechanisms involved in their formation remain unclear. Here we show that the formation of aerosols in Titan's upper atmosphere is directly related to ion processes, and we provide a complete interpretation of observed mass spectra by the Cassini instruments from small to large masses. Because all planetary atmospheres possess ionospheres, we anticipate that the mechanisms identified here will be efficient in other environments as well, modulated by the chemical complexity of each atmosphere. PMID:23382231

  6. The regime of biomass burning aerosols over the Mediterranean basin based on satellite observations

    Science.gov (United States)

    Kalaitzi, Nikoleta; Gkikas, Antonis; Papadimas, Christos. D.; Hatzianastassiou, Nikolaos; Torres, Omar; Mihalopoulos, Nikolaos

    2016-04-01

    Biomass burning (BB) aerosol particles have significant effects on global and regional climate, as well as on regional air quality, visibility, cloud processes and human health.Biomass burning contributes by about 40% to the global emission of black carbonBC, and BB aerosols can exert a significant positive radiative forcing. The BB aerosols can originate from natural fires and human induced burning, such as wood or agricultural waste. However, the magnitude, but also the sign of the radiative forcing of BB aerosols is still uncertain, according to the third assessment report of IPCC (2013). Moreover, there are significant differences between different models as to their representation (inventories) of BB aerosols, more than for others, e.g. of fossil fuel origin. Therefore, it is important to better understand the spatial and temporal regime of BB aerosols. This is attempted here for the broader Mediterranean basin, which is a very interesting study area for aerosols, also being one of the most climaticallysensitive world regions. The determination of spatial and temporal regime of Mediterranean BB aerosols premises the identification of these particles at a complete spatial and long temporal coverage. Such a complete coverage is only ensured by contemporary satellite observations, which offer a challenging ability to characterize the existence of BB aerosols. This is possible thanks to the current availability of derived satellite products offering information on the size and absorption/scattering ability of aerosol particles. A synergistic use of such satellite aerosol data is made here, in conjunction with a developed algorithm, in order to identify the existence of BB aerosols over the Mediterranean basin over the 11-year period from 2005 to 2015. The algorithm operates, on a daily basis and at 1°×1°latitude-longitude resolution, setting threshold values (criteria) for specific physical and optical properties, which are representative of BB aerosols. More

  7. Aerosol Transmission of Filoviruses

    Directory of Open Access Journals (Sweden)

    Berhanu Mekibib

    2016-05-01

    Full Text Available Filoviruses have become a worldwide public health concern because of their potential for introductions into non-endemic countries through international travel and the international transport of infected animals or animal products. Since it was first identified in 1976, in the Democratic Republic of Congo (formerly Zaire and Sudan, the 2013–2015 western African Ebola virus disease (EVD outbreak is the largest, both by number of cases and geographical extension, and deadliest, recorded so far in medical history. The source of ebolaviruses for human index case(s in most outbreaks is presumptively associated with handling of bush meat or contact with fruit bats. Transmission among humans occurs easily when a person comes in contact with contaminated body fluids of patients, but our understanding of other transmission routes is still fragmentary. This review deals with the controversial issue of aerosol transmission of filoviruses.

  8. Aerosol Transmission of Filoviruses.

    Science.gov (United States)

    Mekibib, Berhanu; Ariën, Kevin K

    2016-01-01

    Filoviruses have become a worldwide public health concern because of their potential for introductions into non-endemic countries through international travel and the international transport of infected animals or animal products. Since it was first identified in 1976, in the Democratic Republic of Congo (formerly Zaire) and Sudan, the 2013-2015 western African Ebola virus disease (EVD) outbreak is the largest, both by number of cases and geographical extension, and deadliest, recorded so far in medical history. The source of ebolaviruses for human index case(s) in most outbreaks is presumptively associated with handling of bush meat or contact with fruit bats. Transmission among humans occurs easily when a person comes in contact with contaminated body fluids of patients, but our understanding of other transmission routes is still fragmentary. This review deals with the controversial issue of aerosol transmission of filoviruses. PMID:27223296

  9. Stratospheric aerosol geoengineering

    International Nuclear Information System (INIS)

    The Geoengineering Model Intercomparison Project, conducting climate model experiments with standard stratospheric aerosol injection scenarios, has found that insolation reduction could keep the global average temperature constant, but global average precipitation would reduce, particularly in summer monsoon regions around the world. Temperature changes would also not be uniform; the tropics would cool, but high latitudes would warm, with continuing, but reduced sea ice and ice sheet melting. Temperature extremes would still increase, but not as much as without geoengineering. If geoengineering were halted all at once, there would be rapid temperature and precipitation increases at 5–10 times the rates from gradual global warming. The prospect of geoengineering working may reduce the current drive toward reducing greenhouse gas emissions, and there are concerns about commercial or military control. Because geoengineering cannot safely address climate change, global efforts to reduce greenhouse gas emissions and to adapt are crucial to address anthropogenic global warming

  10. Identification of secondary organic aerosols based on aerosol mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so far.Due to the complex chemical composition of organic aerosols,the identification of SOA has been a hotspot and difficult issue in the field of aerosol study.This study attempts to quantitatively identify SOA in winter of Shenzhen based on positive matrix factorization (PMF) analysis.Major sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer measurement.It showed that in the winter of Shenzhen the average SOA concentration was 9.41±6.33 g/m 3,accounting for 39.9±21.8% of the total organic mass.Compared with primary organic aerosol (POA),the SOA concentrations had no large variation,suggestive of characteristics of regional secondary pollutants.The ratio of SOA/BC had pronounced diurnal variation,similar to that of O x (O3+NO2),indicating SOA formation was significantly controlled by activity of photochemistry in the atmosphere.The most effective period for SOA formation was from 9 am~3 pm since the SOA/BC ratio increased by 122% during this period.This study provides a new technical method and a new idea for SOA investigation.

  11. Aerosol Size Distributions In Auckland.

    Czech Academy of Sciences Publication Activity Database

    Coulson, G.; Olivares, G.; Talbot, Nicholas

    2016-01-01

    Roč. 50, č. 1 (2016), s. 23-28. E-ISSN 1836-5876 Institutional support: RVO:67985858 Keywords : aerosol size distribution * particle number concentration * roadside Subject RIV: CF - Physical ; Theoretical Chemistry

  12. Aerosols Produced by Cosmic Rays

    DEFF Research Database (Denmark)

    Enghoff, Martin Andreas Bødker

    our investigation at the smallest scales, namely the role of cosmic ray produced ions on atmospheric aerosol nucleation and growth processes. Aerosol theory suggests that this is one of the most promising areas to search for an effect. However, guided by the nature of our initial results, it will be...... mechanism linking cosmic rays to clouds and climate is currently speculative, there have been various suggestions of the role atmospheric ions may play; these involve any one of a number of processes from the nucleation of aerosols up to the collection processes of cloud droplets. We have chosen to start...... applied to control the number of ions present. This will enable experiments to be performed both with and without the presence of ions, thus providing information as to the potential role of ions in aerosol processes....

  13. Highly Resolved Paleoclimatic Aerosol Records

    DEFF Research Database (Denmark)

    Kettner, Ernesto

    to paleotemperatures. Impurities in the matrix are comprised of particulate and soluble aerosols, each carrying information on its source’s activitiy and|or proximity. Opposed to gases and water isotopes, the seasonality of many aerosols is not smoothed out in the firn column so that large concentration gradients...... with frequently changing signs are preserved. Therefore, these aerosol records can be used for dating by annual layer counting. However, with increasing depth the annual layer thicknesses decreases due to pressure and ice flow and accurate dating is possible only as long as the rapid variations can be resolved...... experimentally. Over the last decades Continuous Flow Analysis (CFA) has become a well-established technique for aerosol quantification. In CFA, a piece of core is melted continuously and the melt water is analysed for an array of chemical impurities. When designing a CFA system, a trilemma between high sample...

  14. Fractionation of aerosols using a mica microfilter cascade

    International Nuclear Information System (INIS)

    During the last few years, we have investigated the production, the properties of the micafilters, and the practical applications of the Cascade Particle Fractionator. The air flow through micafilters has been measured experimentally at 300 deg C gas temperature. The through-put can be calculated in a semiempirical capillary model. A cascade arrangement of differentially coordinated mica filters was used to clean the industrial waste gas at the NUKEM-sinter oven at Hanau. Micafilters with sharp-edged and rounded-off entrance and exit channels were used. During the filtration a complete separation and fractionation of particles by size and shape has been obtained. The analytical studies of the separated aerosol particles using an electron microprobe (SEM and X-ray fluorescence spectroscopy) and other analytical methods allow determination of the particle size distribution. A preliminary comparison between our cascade particle fractionator and Andersen cascade impactors is presented with respect to aerosol separation and fractionation. (author)

  15. Survival of bacteria during aerosolization.

    OpenAIRE

    Marthi, B; Fieland, V P; Walter, M.; Seidler, R J

    1990-01-01

    One form of commercial application of microorganisms, including genetically engineered microorganisms is as an aerosol. To study the effect of aerosol-induced stress on bacterial survival, nonrecombinant spontaneous antibiotic-resistant mutants of four organisms, Enterobacter cloacae, Erwinia herbicola, Klebsiella planticola, and Pseudomonas syringae, were sprayed in separate experiments in a greenhouse. Samples were collected over a distance of 15 m from the spray site for enumeration. Spore...

  16. The removal of sodium aerosols

    International Nuclear Information System (INIS)

    This paper is concentrated on the removal of sodium combustion aerosol. The experimental results are presented in it. Besides, the output of the aerosol, the igniting point and combustion rate of sodium are also obtained. An experimental device for removing of the aerosol consists of a blower, sodium combustion container, water-spraying column, water storage tank and nitrogen bottle. In order to compare the concentrations at the outlet of the column before and after the water-spraying, the concentration distribution was measured in the process of sodium burning. It was found that similar concentration could be obtained from sixth to eighth minute after ignition of sodium in the container. During the interval the water-spraying was performed, the measurement of the aerosol concentrations at different water-spray height was proceeded. The removing efficiency of the aerosol at different water-spraying heights is different. The efficiency at the height of 1220 mm is near to maximum. The results show that further increasing water-spray height could not greatly reduce the concentration of the aerosol at the outlet. (author)

  17. Comparison of sodium aerosol codes

    International Nuclear Information System (INIS)

    Although hypothetical fast reactor accidents leading to severe core damage are very low probability events, their consequences are to be assessed. During such accidents, one can envisage the ejection of sodium, mixed with fuel and fission products, from the primary circuit into the secondary containment. Aerosols can be formed either by mechanical dispersion of the molten material or as a result of combustion of the sodium in the mixture. Therefore considerable effort has been devoted to study the different sodium aerosol phenomena. To ensure that the problems of describing the physical behaviour of sodium aerosols were adequately understood, a comparison of the codes being developed to describe their behaviour was undertaken. The comparison consists of two parts. The first is a comparative study of the computer codes used to predict aerosol behaviour during a hypothetical accident. It is a critical review of documentation available. The second part is an exercise in which code users have run their own codes with a pre-arranged input. For the critical comparative review of the computer models, documentation has been made available on the following codes: AEROSIM (UK), MAEROS (USA), HAARM-3 (USA), AEROSOLS/A2 (France), AEROSOLS/B1 (France), and PARDISEKO-IIIb (FRG)

  18. Aerosol generation and delivery in medical applications

    International Nuclear Information System (INIS)

    It is well established that radioaerosol lung technique by inhalation is a very versatile technique in the evaluation of health effects and medical diagnostic applications, especially to detect chronic obstructive pulmonary diseases, their defence mechanism permeability and many others. Most important part of aerosol technology is to generate reproducibly stable diagnostic radioaerosols of known characteristics. Many compressed air atomisers are commercially available for generating aerosols but they have limited utility in aerosol inhalation, either because of large droplet size, low aerosol output or high airflow rates. There is clearly a need for a versatile and economical aerosol generation/inhalation system that can produce dry labelled aerosol particles with high deep lung delivery efficiency suitable for clinical studies. BARC (Bhabha Atomic Research Centre) has developed a dry aerosol generation/delivery system which operates on compressed air and generates dry polydisperse aerosols. This system is described along with an assessment of the aerosol characteristics and efficiency for diagnosis of various respiratory disorders

  19. Devices and methods for generating an aerosol

    KAUST Repository

    Bisetti, Fabrizio

    2016-03-03

    Aerosol generators and methods of generating aerosols are provided. The aerosol can be generated at a stagnation interface between a hot, wet stream and a cold, dry stream. The aerosol has the benefit that the properties of the aerosol can be precisely controlled. The stagnation interface can be generated, for example, by the opposed flow of the hot stream and the cold stream. The aerosol generator and the aerosol generation methods are capable of producing aerosols with precise particle sizes and a narrow size distribution. The properties of the aerosol can be controlled by controlling one or more of the stream temperatures, the saturation level of the hot stream, and the flow times of the streams.

  20. Aerosol climatology over Nile Delta based on MODIS, MISR and OMI satellite data

    Science.gov (United States)

    Marey, H. S.; Gille, J. C.; El-Askary, H. M.; Shalaby, E. A.; El-Raey, M. E.

    2011-10-01

    Since 1999 Cairo and the Nile delta region have suffered from air pollution episodes called the "black cloud" during the fall season. These have been attributed to either burning of agriculture waste or long-range transport of desert dust. Here we present a detailed analysis of the optical and microphysical aerosol properties, based on satellite data. Monthly mean values of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD) at 550 nm were examined for the 10 yr period from 2000-2009. Significant monthly variability is observed in the AOD with maxima in April or May (~0.5) and October (~0.45), and a minimum in December and January (~0.2). Monthly mean values of UV Aerosol Index (UVAI) retrieved by the Ozone Monitoring Instrument (OMI) for 4 yr (2005-2008) exhibit the same AOD pattern. The carbonaceous aerosols during the black cloud periods are confined to the planetary boundary layer (PBL), while dust aerosols exist over a wider range of altitudes, as shown by Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) aerosol profiles. The monthly climatology of Multi-angle Imaging SpectroRadiometer (MISR) data show that the aerosols during the black cloud periods are spherical with a higher percentage of small and medium size particles, whereas the spring aerosols are mostly large non-spherical particles. All of the results show that the air quality in Cairo and the Nile delta region is subject to a complex mixture of air pollution types, especially in the fall season, when biomass burning contributes to a background of urban pollution and desert dust.

  1. Aerosol climatology over Nile Delta based on MODIS, MISR and OMI satellite data

    Directory of Open Access Journals (Sweden)

    H. S. Marey

    2011-10-01

    Full Text Available Since 1999 Cairo and the Nile delta region have suffered from air pollution episodes called the "black cloud" during the fall season. These have been attributed to either burning of agriculture waste or long-range transport of desert dust. Here we present a detailed analysis of the optical and microphysical aerosol properties, based on satellite data. Monthly mean values of Moderate Resolution Imaging Spectroradiometer (MODIS aerosol optical depth (AOD at 550 nm were examined for the 10 yr period from 2000–2009. Significant monthly variability is observed in the AOD with maxima in April or May (~0.5 and October (~0.45, and a minimum in December and January (~0.2. Monthly mean values of UV Aerosol Index (UVAI retrieved by the Ozone Monitoring Instrument (OMI for 4 yr (2005–2008 exhibit the same AOD pattern. The carbonaceous aerosols during the black cloud periods are confined to the planetary boundary layer (PBL, while dust aerosols exist over a wider range of altitudes, as shown by Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO aerosol profiles. The monthly climatology of Multi-angle Imaging SpectroRadiometer (MISR data show that the aerosols during the black cloud periods are spherical with a higher percentage of small and medium size particles, whereas the spring aerosols are mostly large non-spherical particles. All of the results show that the air quality in Cairo and the Nile delta region is subject to a complex mixture of air pollution types, especially in the fall season, when biomass burning contributes to a background of urban pollution and desert dust.

  2. Aerosol Climatology over Nile Delta based on MODIS, MISR and OMI satellite data

    Directory of Open Access Journals (Sweden)

    H. S. Marey

    2011-04-01

    Full Text Available Since 1999 Cairo and the Nile delta region have suffered from air pollution episodes called the "black cloud" during the fall season. These have been attributed to either burning of agriculture waste or long-range transport of desert dust. Here we present a detailed analysis of the optical and microphysical aerosol properties, based on satellite data. Monthly mean values of Moderate Resolution Imaging Spectroradiometer (MODIS aerosol optical depth (AOD at 550 nm were examined for the 10 yr 2000–2009. Significant monthly variability is observed with maxima in April or May (~0.5 and October (~0.45, and a minimum in December and January (~0.2. Monthly mean values of UV Aerosol Index (UVAI retrieved by the Ozone Monitoring Instrument (OMI for 4 yr (2005–2008 exhibit the same AOD pattern. The carbonaceous aerosols during the black cloud periods are confined to the planetary boundary layer (PBL, while dust aerosols exist over a wider range of altitudes, as shown by Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO aerosol profiles. The monthly climatology of Multi-angle Imaging SpectroRadiometer (MISR data show that the aerosols during the black cloud periods are spherical with a higher percentage of small and medium size particles, whereas the spring aerosols are mostly large non-spherical particles. All of the results show that the air quality in Cairo and the Nile delta region is subject to a complex mixture of air pollution types, especially in the fall season, when biomass burning contributes to a background of urban pollution and desert dust.

  3. How important is organic aerosol hygroscopicity to aerosol indirect forcing?

    International Nuclear Information System (INIS)

    Organics are among the most abundant aerosol components in the atmosphere. However, there are still large uncertainties with emissions of primary organic aerosol (POA) and volatile organic compounds (VOCs) (precursor gases of secondary organic aerosol, SOA), formation of SOA, and chemical and physical properties (e.g., hygroscopicity) of POA and SOA. All these may have significant impacts on aerosol direct and indirect forcing estimated from global models. In this study a modal aerosol module (MAM) in the NCAR community atmospheric model (CAM) is used to examine sensitivities of aerosol indirect forcing to hygroscopicity (represented by a single parameter 'κ' ) of POA and SOA. Our model simulation indicates that in the present-day (PD) condition changing the 'κ' value of POA from 0 to 0.1 increases the number concentration of cloud condensational nuclei (CCN) at supersaturation S = 0.1% by 40-80% over the POA source regions, while changing the 'κ' value of SOA by ± 50% (from 0.14 to 0.07 and 0.21) changes the CCN concentration within 40%. There are disproportionally larger changes in CCN concentration in the pre-industrial (PI) condition. Due to the stronger impact of organics hygroscopicity on CCN and cloud droplet number concentration at PI condition, global annual mean anthropogenic aerosol indirect forcing (AIF) between PD and PI conditions reduces with the increase of the hygroscopicity of organics. Global annual mean AIF varies by 0.4 W m-2 in the sensitivity runs with the control run of - 1.3 W m-2, highlighting the need for improved understanding of organics hygroscopicity and its representation in global models.

  4. ZERO WASTE

    OpenAIRE

    Upadhyaya, Luv

    2013-01-01

    The aim of the thesis was to develop a clear vision on better waste management system. The thesis introduced the sustainable waste management along with innovation. The aim of the research was to find out the types of waste being introduced to environment, their consequence on human beings and surroundings, best policies, principles and practices to minimize the effect of the waste to lowest. The study was based on literature. The thesis includes the introduction of types of waste, clarifi...

  5. Current therapies and technological advances in aqueous aerosol drug delivery.

    Science.gov (United States)

    Watts, Alan B; McConville, Jason T; Williams, Robert O

    2008-09-01

    Recent advances in aerosolization technology have led to renewed interest in pulmonary delivery of a variety of drugs. Pressurized metered dose inhalers (pMDIs) and dry powder inhalers (DPIs) have experienced success in recent years; however, many limitations are presented by formulation difficulties, inefficient delivery, and complex device designs. Simplification of the formulation process as well as adaptability of new devices has led many in the pharmaceutical industry to reconsider aerosolization in an aqueous carrier. In the acute care setting, breath-enhanced air-jet nebulizers are controlling and minimizing the amount of wasted medication, while producing a high percentage of respirable droplets. Vibrating mesh nebulizers offer advantages in higher respirable fractions (RFs) and slower velocity aerosols when compared with air-jet nebulizers. Vibrating mesh nebulizers incorporating formulation and patient adaptive components provide improvements to continuous nebulization technology by generating aerosol only when it is most likely to reach the deep lung. Novel innovations in generation of liquid aerosols are now being adapted for propellant-free pulmonary drug delivery to achieve unprecedented control over dose delivered and are leading the way for the adaptation of systemic drugs for delivery via the pulmonary route. Devices designed for the metered dose delivery of insulin, morphine, sildenafil, triptans, and various peptides are all currently under investigation for pulmonary delivery to treat nonrespiratory diseases. Although these devices are currently still in clinical testing (with the exception of the Respimat), metered dose liquid inhalers (MDLIs) have already shown superior outcomes to current pulmonary and systemic delivery methods. PMID:18663654

  6. Rotational raman lidar for aerosol scattering coefficients

    International Nuclear Information System (INIS)

    Two channel lidar signals which are composed of the total rotational scattering and elastic signals provide good information for the aerosol scattering coefficients. We can calculate the aerosol backscattering coefficient and extinction coefficient directly without any assumption and calibration process. Generally, a high spectral resolution lidar is used for an aerosol monitoring. But we have designed a new normal spectral receiving lidar system which contains the scattering information simultaneously, and we have retrieved the aerosol scattering coefficient. The results show that there is no need to assume any relation between the aerosol backscattering and extinction and to consider any wavelength calibration process for the aerosol scattering coefficient

  7. Aerosol properties and associated radiative effects over Cairo (Egypt)

    Science.gov (United States)

    El-Metwally, M.; Alfaro, S. C.; Wahab, M. M. Abdel; Favez, O.; Mohamed, Z.; Chatenet, B.

    2011-02-01

    Cairo is one of the largest megacities in the World and the particle load of its atmosphere is known to be particularly important. In this work we aim at assessing the temporal variability of the aerosol's characteristics and the magnitude of its impacts on the transfer of solar radiation. For this we use the level 2 quality assured products obtained by inversion of the instantaneous AERONET sunphotometer measurements performed in Cairo during the Cairo Aerosol CHaracterization Experiment (CACHE), which lasted from the end of October 2004 to the end of March 2006. The analysis of the temporal variation of the aerosol's optical depth (AOD) and spectral dependence suggests that the aerosol is generally a mixture of at least 3 main components differing in composition and size. This is confirmed by the detailed analysis of the monthly-averaged size distributions and associated optical properties (single scattering albedo and asymmetry parameter). The components of the aerosol are found to be 1) a highly absorbing background aerosol produced by daily activities (traffic, industry), 2) an additional, 'pollution' component produced by the burning of agricultural wastes in the Nile delta, and 3) a coarse desert dust component. In July, an enhancement of the accumulation mode is observed due to the atmospheric stability favoring its building up and possibly to secondary aerosols being produced by active photochemistry. More generally, the time variability of the aerosol's characteristics is due to the combined effects of meteorological factors and seasonal production processes. Because of the large values of the AOD achieved during the desert dust and biomass burning episodes, the instantaneous aerosol radiative forcing (RF) at both the top (TOA) and bottom (BOA) of the atmosphere is maximal during these events. For instance, during the desert dust storm of April 8, 2005 RF BOA, RF TOA, and the corresponding atmospheric heating rate peaked at - 161.7 W/m 2, - 65.8 W/m 2

  8. Environmental pollution from solid wastes

    International Nuclear Information System (INIS)

    Research completed under the CRP during the past two years has encompassed several related aspects of environmental problems associated with solid wastes: assessment of major sources of toxic elements in a variety of solid waste forms, their leachability by simulated groundwater or rain/acid rain and the determination of the contribution of hospital incinerator to atmospheric releases. The summary of the findings of these investigations are given in this report. Unexpected high levels of cadmium have been found in many solid wastes. Leaching tests indicate that, in some cases, over 70% of this can be leached out into the nearby waterways. Combustibility tests indicated that 35 to 45% of it is emitted to the atmosphere during burning. This explains the increased levels of cadmium in air particulates sampled downwind from waste incinerators. Plastic items in municipal and hospital wastes were particularly elevated in Cd, Cl, Cr, Ba and Zn. Up to 1300 μg/g of Cd was found in some domestic items. By inference, Pb also is found in some common plastics but the current studies did not permit Pb determination in solid wastes, but only in aerosols. (author). 8 tabs

  9. Effect of aerosol sub-grid variability on aerosol optical depth and cloud condensation nuclei: Implications for global aerosol modelling

    OpenAIRE

    Weigum, N; Schutgens, N.; Stier, P.

    2016-01-01

    A fundamental limitation of grid-based models is their inability to resolve variability on scales smaller than a grid box. Past research has shown that significant aerosol variability exists on scales smaller than these grid-boxes, which can lead to discrepancies in simulated aerosol climate effects between high and low resolution models. This study investigates the impact of neglecting sub-grid variability in present-day global microphysical aerosol models on aerosol optical depth (AOD) and ...

  10. Using the OMI aerosol index and absorption aerosol optical depth to evaluate the NASA MERRA Aerosol Reanalysis

    OpenAIRE

    Buchard, V.; A. M. Silva; P. R. Colarco; Darmenov, A.; C. A. Randles; Govindaraju, R.; O. Torres; Campbell, J.; R. Spurr

    2015-01-01

    A radiative transfer interface has been developed to simulate the UV aerosol index (AI) from the NASA Goddard Earth Observing System version 5 (GEOS-5) aerosol assimilated fields. The purpose of this work is to use the AI and aerosol absorption optical depth (AAOD) derived from the Ozone Monitoring Instrument (OMI) measurements as independent validation for the Modern Era Retrospective analysis for Research and Applications Aerosol Reanalysis (MERRAero). MERRAero is based on...

  11. Hazardous wastes

    International Nuclear Information System (INIS)

    The dangers and problems of hazardous wastes are described in this pictorial booklet that is part of the EPA solid waste management publication series. It is shown that how the nation's hazardous wastes are managed or mismanaged is a crucial environmental issue with vast implications for public health and for the integrity of the ecological systems on which man depends. The environmental folly of dumping or burning these wastes is emphasized, along with the economic imprudence of continuing to throw away valuable resources as wastes. The public as well as industry must pay the costs of safe hazardous waste management

  12. Factors Affecting Aerosol Radiative Forcing

    Science.gov (United States)

    Wang, Jingxu; Lin, Jintai; Ni, Ruijing

    2016-04-01

    Rapid industrial and economic growth has meant a large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RF of aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissions per unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size. South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions, its aerosol RF is alleviated by its lowest chemical efficiency. The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is lowered by a small per capita GDP. Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The

  13. Atmospheric carbonaceous aerosols from Indo-Gangetic Plain and Central Himalaya: impact of anthropogenic sources.

    Science.gov (United States)

    Ram, Kirpa; Sarin, M M

    2015-01-15

    In the present-day scenario of growing anthropogenic activities, carbonaceous aerosols contribute significantly (∼20-70%) to the total atmospheric particulate matter mass and, thus, have immense potential to influence the Earth's radiation budget and climate on a regional to global scale. In addition, formation of secondary organic aerosols is being increasingly recognized as an important process in contributing to the air-pollution and poor visibility over urban regions. It is, thus, essential to study atmospheric concentrations of carbonaceous species (EC, OC and WSOC), their mixing state and absorption properties on a regional scale. This paper presents the comprehensive data on emission sources, chemical characteristics and optical properties of carbonaceous aerosols from selected urban sites in the Indo-Gangetic Plain (IGP) and from a high-altitude location in the central Himalaya. The mass concentrations of OC, EC and WSOC exhibit large spatio-temporal variability in the IGP. This is attributed to seasonally varying emissions from post-harvest agricultural-waste burning, their source strength, boundary layer dynamics and secondary aerosol formation. The high concentrations of OC and SO4(2-), and their characteristic high mass scattering efficiency, contribute significantly to the aerosol optical depth and scattering coefficient. This has implications to the assessment of single scattering albedo and aerosol radiative forcing on a regional scale. PMID:25199599

  14. Miniature Sensor for Aerosol Mass Measurements Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR project seeks to develop a miniature sensor for mass measurement of size-classified aerosols. A cascade impactor will be used to classify aerosol sample...

  15. MISR Aerosol Climatology Product V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This product is 1)the microphysical and scattering characteristics of pure aerosol upon which routine retrievals are based;2)mixtures of pure aerosol to be compared...

  16. Aerosol Climate Time Series in ESA Aerosol_cci

    Science.gov (United States)

    Popp, Thomas; de Leeuw, Gerrit; Pinnock, Simon

    2016-04-01

    Within the ESA Climate Change Initiative (CCI) Aerosol_cci (2010 - 2017) conducts intensive work to improve algorithms for the retrieval of aerosol information from European sensors. Meanwhile, full mission time series of 2 GCOS-required aerosol parameters are completely validated and released: Aerosol Optical Depth (AOD) from dual view ATSR-2 / AATSR radiometers (3 algorithms, 1995 - 2012), and stratospheric extinction profiles from star occultation GOMOS spectrometer (2002 - 2012). Additionally, a 35-year multi-sensor time series of the qualitative Absorbing Aerosol Index (AAI) together with sensitivity information and an AAI model simulator is available. Complementary aerosol properties requested by GCOS are in a "round robin" phase, where various algorithms are inter-compared: fine mode AOD, mineral dust AOD (from the thermal IASI spectrometer, but also from ATSR instruments and the POLDER sensor), absorption information and aerosol layer height. As a quasi-reference for validation in few selected regions with sparse ground-based observations the multi-pixel GRASP algorithm for the POLDER instrument is used. Validation of first dataset versions (vs. AERONET, MAN) and inter-comparison to other satellite datasets (MODIS, MISR, SeaWIFS) proved the high quality of the available datasets comparable to other satellite retrievals and revealed needs for algorithm improvement (for example for higher AOD values) which were taken into account for a reprocessing. The datasets contain pixel level uncertainty estimates which were also validated and improved in the reprocessing. For the three ATSR algorithms the use of an ensemble method was tested. The paper will summarize and discuss the status of dataset reprocessing and validation. The focus will be on the ATSR, GOMOS and IASI datasets. Pixel level uncertainties validation will be summarized and discussed including unknown components and their potential usefulness and limitations. Opportunities for time series extension

  17. Aerosol MALDI mass spectrometry for bioaerosol analysis

    OpenAIRE

    Kleefsman, W.A.

    2008-01-01

    In the thesis Aerosol MALDI mass spectrometry for bioaerosol analysis is described how the aerosol mass spectrometer of the TU Delft has been further developed for the on-line analysis of bioaerosols. Due to the implemented improvements mass spectra with high resolution and a high mass range can be obtained from single protein containing aerosol particles. Fluorescence is used to select the biological fraction of an aerosol: when a particle emits fluorescence when irradiated with UV-laser lig...

  18. Origins of atmospheric aerosols. Basic concepts on aerosol main physical properties; L`aerosol atmospherique: ses origines quelques notions sur les principales proprietes physiques des aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Renoux, A. [Paris-12 Univ., 94 - Creteil (France). Laboratoire de Physique des aerosols et de transferts des contaminations

    1996-12-31

    Natural and anthropogenic sources of atmospheric aerosols are reviewed and indications of their concentrations and granulometry are given. Calculation of the lifetime of an atmospheric aerosol of a certain size is presented and the various modes of aerosol granulometry and their relations with photochemical and physico-chemical processes in the atmosphere are discussed. The main physical, electrical and optical properties of aerosols are also presented: diffusion coefficient, dynamic mobility and relaxation time, Stokes number, limit rate of fall, electrical mobility, optical diffraction

  19. Natural aerosol direct and indirect radiative effects

    OpenAIRE

    Rap, Alexandru; Scott, Catherine E.; Spracklen, Dominick V; Bellouin, Nicolas; Forster, Piers M.; Carslaw, Kenneth S.; Schmidt, Anja; Mann, Graham

    2013-01-01

    Natural aerosol plays a significant role in the Earth's system due to its ability to alter the radiative balance of the Earth. Here we use a global aerosol microphysics model together with a radiative transfer model to estimate radiative effects for five natural aerosol sources in the present-day atmosphere: dimethyl sulfide (DMS), sea-salt, volcanoes, monoterpenes, and wildfires. We calculate large annual global mean aerosol direct and cloud albedo effects especially for DMS-derived sulfate ...

  20. Aerosol filtration with metallic fibrous filters

    International Nuclear Information System (INIS)

    The filtration efficiency of stainless steel fibrous filters (BEKIPOR porous mats and sintered webs) is determined using submicronic monodisperse polystyrene aerosols. Lasers spectrometers are used for the aerosol measurements. The parameters varied are the fiber diameter, the number of layers, the aerosol diameter and the superficial velocity. Two selected types of filters are tested with polydisperse methylene blue aerosols to determine the effect of bed loading on the filter performance and to test washing techniques for the regeneration of the filter

  1. Textile Wastes.

    Science.gov (United States)

    Talbot, R. S.

    1978-01-01

    Presents a literature review of wastes from textile industry, covering publications of 1977. This review covers studies such as removing heavy metals in textile wastes, and the biodegradability of six dyes. A list of references is also presented. (HM)

  2. Waste management

    DEFF Research Database (Denmark)

    Bruun Hansen, Karsten; Jamison, Andrew

    2000-01-01

    The case study deals with public accountability issues connected to household waste management in the municipality of Copenhagen, Denmark.......The case study deals with public accountability issues connected to household waste management in the municipality of Copenhagen, Denmark....

  3. Aerosol retrieval experiments in the ESA Aerosol_cci project

    Directory of Open Access Journals (Sweden)

    T. Holzer-Popp

    2013-08-01

    Full Text Available Within the ESA Climate Change Initiative (CCI project Aerosol_cci (2010–2013, algorithms for the production of long-term total column aerosol optical depth (AOD datasets from European Earth Observation sensors are developed. Starting with eight existing pre-cursor algorithms three analysis steps are conducted to improve and qualify the algorithms: (1 a series of experiments applied to one month of global data to understand several major sensitivities to assumptions needed due to the ill-posed nature of the underlying inversion problem, (2 a round robin exercise of "best" versions of each of these algorithms (defined using the step 1 outcome applied to four months of global data to identify mature algorithms, and (3 a comprehensive validation exercise applied to one complete year of global data produced by the algorithms selected as mature based on the round robin exercise. The algorithms tested included four using AATSR, three using MERIS and one using PARASOL. This paper summarizes the first step. Three experiments were conducted to assess the potential impact of major assumptions in the various aerosol retrieval algorithms. In the first experiment a common set of four aerosol components was used to provide all algorithms with the same assumptions. The second experiment introduced an aerosol property climatology, derived from a combination of model and sun photometer observations, as a priori information in the retrievals on the occurrence of the common aerosol components. The third experiment assessed the impact of using a common nadir cloud mask for AATSR and MERIS algorithms in order to characterize the sensitivity to remaining cloud contamination in the retrievals against the baseline dataset versions. The impact of the algorithm changes was assessed for one month (September 2008 of data: qualitatively by inspection of monthly mean AOD maps and quantitatively by comparing daily gridded satellite data against daily averaged AERONET sun

  4. Aerosols and fission product transport

    International Nuclear Information System (INIS)

    A survey is presented of current knowledge of the possible role of aerosols in the consequences of in- and out-of-core LOCAs and of end fitting failures in CANDU reactors. An extensive literature search has been made of research on the behaviour of aerosols in possible accidents in water moderated and cooled reactors and the results of various studies compared. It is recommended that further work should be undertaken on the formation of aerosols during these possible accidents and to study their subsequent behaviour. It is also recommended that the fission products behaviour computer code FISSCON II should be re-examined to determine whether it reflects the advances incorporated in other codes developed for light water reactors which have been extensively compared. 47 refs

  5. Air ions and aerosol science

    Science.gov (United States)

    Tammet, Hannes

    1996-03-01

    Collaboration between Gas Discharge and Plasma Physics, Atmospheric Electricity, and Aerosol Science is a factor of success in the research of air ions. The concept of air ion as of any carrier of electrical current through the air is inherent to Atmospheric Electricity under which a considerable statistical information about the air ion mobility spectrum is collected. A new model of air ion size-mobility correlation has been developed proceeding from Aerosol Science and joining the methods of neighboring research fields. The predicted temperature variation of the mobility disagrees with the commonly used Langevin rule for the reduction of air ion mobilities to the standard conditions. Concurrent errors are too big to be neglected in applications. The critical diameter distinguishing cluster ions and charged aerosol particles has been estimated to be 1.4-1.8 nm.

  6. Air ions and aerosol science

    Energy Technology Data Exchange (ETDEWEB)

    Tammet, H. [Department of Environmental Physics, Tartu University, Tartu, Estonia (Estonia) 2400

    1996-03-01

    Collaboration between Gas Discharge and Plasma Physics, Atmospheric Electricity, and Aerosol Science is a factor of success in the research of air ions. The concept of air ion as of any carrier of electrical current through the air is inherent to Atmospheric Electricity under which a considerable statistical information about the air ion mobility spectrum is collected. A new model of air ion size-mobility correlation has been developed proceeding from Aerosol Science and joining the methods of neighboring research fields. The predicted temperature variation of the mobility disagrees with the commonly used Langevin rule for the reduction of air ion mobilities to the standard conditions. Concurrent errors are too big to be neglected in applications. The critical diameter distinguishing cluster ions and charged aerosol particles has been estimated to be 1.4{endash}1.8 nm. {copyright} {ital 1996 American Institute of Physics.}

  7. Characterization of Florida red tide aerosol and the temporal profile of aerosol concentration

    OpenAIRE

    Cheng, Yung Sung; Zhou, Yue; Pierce, Richard H.; Henry, Mike; Baden, Daniel G.

    2009-01-01

    Red tide aerosols containing aerosolized brevetoxins are produced during the red tide bloom and transported by wind to coastal areas of Florida. This study reports the characterization of Florida red tide aerosols in human volunteer studies, in which an asthma cohort spent 1 h on Siesta Beach (Sarasota, Florida) during aerosolized red tide events and non-exposure periods. Aerosol concentrations, brevetoxin levels, and particle size distribution were measured. Hourly filter samples were taken ...

  8. The relationship between aerosol and cloud drop number concentrations in a global aerosol microphysics model

    OpenAIRE

    Pringle, K. J.; Carslaw, K. S.; D. V. Spracklen; Mann, G. M.; M. P. Chipperfield

    2009-01-01

    Empirical relationships that link cloud droplet number (CDN) to aerosol number or mass are commonly used to calculate global fields of CDN for climate forcing assessments. In this work we use a sectional global model of sulfate and sea-salt aerosol coupled to a mechanistic aerosol activation scheme to explore the limitations of this approach. We find that a given aerosol number concentration produces a wide range of CDN concentrations due to variations in the shape of the aerosol size distrib...

  9. ATI TDA 5A aerosol generator evaluation

    International Nuclear Information System (INIS)

    Oil based aerosol ''Smoke'' commonly used for testing the efficiency and penetration of High Efficiency Particulate Air filters (HEPA) and HEPA systems can produce flammability hazards that may not have been previously considered. A combustion incident involving an aerosol generator has caused an investigation into the hazards of the aerosol used to test HEPA systems at Hanford

  10. Food waste

    OpenAIRE

    Arazim, Lukáš

    2015-01-01

    This thesis looks into issues related to food waste and consists of a theoretical and a practical part. Theoretical part aims to provide clear and complex definition of wood waste related problems, summarize current findings in Czech and foreign sources. Introduction chapter explains important terms and legal measures related to this topic. It is followed by description of causes, implications and possibilities in food waste reduction. Main goal of practical part is analyzing food waste in Cz...

  11. Waste incineration

    International Nuclear Information System (INIS)

    Waste incineration can be defined as the thermal conversion processing of solid waste by chemical oxidation. The types of wastes range from solid household waste and infectious hospital waste through to toxic solid, liquid and gaseous chemical wastes. End products include hot incineration gases, composed primarily of nitrogen, carbon dioxide, water vapor and to a smaller extend of non-combustible residue (ash) and air pollutants (e. g. NOx). Energy can be recovered by heat exchange from the hot incineration gases, thus lowering fossil fuel consumption that in turn can reduce emissions of greenhouse gases. Burning of solid waste can fulfil up to four distinctive objectives (Pera, 2000): 1. Volume reduction: volume reduction of about 90 %, weight reduction of about 70 %; 2. Stabilization of waste: oxidation of organic input; 3. Recovery of energy from waste; 4. Sanitization of waste: destruction of pathogens. Waste incineration is not a means to make waste disappear. It does entail emissions into air as well as water and soil. The generated solid residues are the topic of this task force. Unlike other industrial processes discussed in this platform, waste incineration is not a production process, and is therefore not generating by-products, only residues. Residues that are isolated from e. g. flue gas, are concentrated in another place and form (e. g. air pollution control residues). Hence, there are generally two groups of residues that have to be taken into consideration: residues generated in the actual incineration process and others generated in the flue gas cleaning system. Should waste incineration finally gain public acceptance, it will be necessary to find consistent regulations for both sorts of residues. In some countries waste incineration is seen as the best option for the treatment of waste, whereas in other countries it is seen very negative. (author)

  12. Aerosol Transport Over Equatorial Africa

    Science.gov (United States)

    Gatebe, C. K.; Tyson, P. D.; Annegarn, H. J.; Kinyua, A. M.; Piketh, S.; King, M.; Helas, G.

    1999-01-01

    Long-range and inter-hemispheric transport of atmospheric aerosols over equatorial Africa has received little attention so far. Most aerosol studies in the region have focussed on emissions from rain forest and savanna (both natural and biomass burning) and were carried out in the framework of programs such as DECAFE (Dynamique et Chimie Atmospherique en Foret Equatoriale) and FOS (Fires of Savanna). Considering the importance of this topic, aerosols samples were measured in different seasons at 4420 meters on Mt Kenya and on the equator. The study is based on continuous aerosol sampling on a two stage (fine and coarse) streaker sampler and elemental analysis by Particle Induced X-ray Emission. Continuous samples were collected for two seasons coinciding with late austral winter and early austral spring of 1997 and austral summer of 1998. Source area identification is by trajectory analysis and sources types by statistical techniques. Major meridional transports of material are observed with fine-fraction silicon (31 to 68 %) in aeolian dust and anthropogenic sulfur (9 to 18 %) being the major constituents of the total aerosol loading for the two seasons. Marine aerosol chlorine (4 to 6 %), potassium (3 to 5 %) and iron (1 to 2 %) make up the important components of the total material transport over Kenya. Minimum sulfur fluxes are associated with recirculation of sulfur-free air over equatorial Africa, while maximum sulfur concentrations are observed following passage over the industrial heartland of South Africa or transport over the Zambian/Congo Copperbelt. Chlorine is advected from the ocean and is accompanied by aeolian dust recirculating back to land from mid-oceanic regions. Biomass burning products are transported from the horn of Africa. Mineral dust from the Sahara is transported towards the Far East and then transported back within equatorial easterlies to Mt Kenya. This was observed during austral summer and coincided with the dying phase of 1997/98 El

  13. Nuclear wastes

    International Nuclear Information System (INIS)

    Here is made a general survey of the situation relative to radioactive wastes. The different kinds of radioactive wastes and the different way to store them are detailed. A comparative evaluation of the situation in France and in the world is made. The case of transport of radioactive wastes is tackled. (N.C.)

  14. The coagulation of radioactive aerosols

    International Nuclear Information System (INIS)

    Radioactive aerosols can become charged by emitting charges during the decay process, and the resulting electrostatic forces will modify coagulation rates. For Brownian coagulation, calculations for nuclear containment aerosols show that rates averaged over charge distributions can be strongly reduced between particles of the same size, but that increases in average rates can occur for particles of different sizes. The increases arise from small, but significant, negative charging of non-radioactive and small-sized radioactive particles, and are sensitive to the asymmetry between the positive and negative ion mobilities. (Author)

  15. Aerosols of Mongolian arid area

    Science.gov (United States)

    Golobokova, L.; Marinayte, I.; Zhamsueva, G.

    2012-04-01

    Sampling was performed in July-August 2005-2010 at Station Sain Shand (44°54'N, 110°07'E) in the Gobi desert (1000 m a.s.l.), West Mongolia. Aerosol samples were collected with a high volume sampler PM 10 (Andersen Instruments Inc., USA) onto Whatman-41 filters. The substance was extracted from the filters by de-ionized water. The solution was screened through an acetate-cellulose filter with 0.2 micron pore size. Ions of ammonium, sodium, potassium, magnesium, and calcium, as well as sulphate ions, nitrate ions, hydrocarbonate, chloride ions were determined in the filtrate by means of an atomic adsorption spectrometer Carl Zeiss Jena (Germany), a high performance liquid chromatographer «Milichrome A-02» (Russia), and an ionic chromatographer ICS-3000 (Dionex, USA). The PAH fraction was separated from aerosol samples using hexane extraction at room temperature under UV environment. The extract was concentrated to 0.1-0.2 ml and analysed by a mass-spectrometer "Agilent, GC 6890, MSD 5973 Network". Analysis of concentrations of aerosols components, their correlation ratios, and meteorological modeling show that the main factor affecting chemical composition of aerosols is a flow of contaminants transferred by air masses to the sampling area mainly from the south and south-east, as well as wind conditions of the area, dust storms in particular. Sulphate, nitrate, and ammonium are major ions in aerosol particles at Station Sain Shand. Dust-borne aerosol is known to be a sorbent for both mineral and organic admixtures. Polycyclic aromatic hydrocarbons (PAH) being among superecotoxicants play an important role among resistant organic substances. PAH concentrations were determined in the samples collected in 2010. All aerosol samples contained dominant PAHs with 5-6 benzene rings ( (benze(k)fluoranthen, benze(b)flouranthen, benze(a)pyren, benze(?)pyren, perylene, benze(g,h,i)perylene, and indene(1,2,3-c,d)pyrene). Their total quantity varied between 42 and 90

  16. Waste Management

    International Nuclear Information System (INIS)

    The objectives of SCK-CEN's programme on radioactive waste management are: (1) to reduce the impact of the waste to the stakeholders, the public and the environment; (2) to develop a management tool allowing to identify waste problems and to optimise decommissioning strategies; (3) to perform decommissioning activities in a safe and economical way; (4) to manage waste in a safe and economical way according to legislation; (5) to develop treatment/conditioning processes to minimise risks, volumes and cost of radioactive waste. Main projects and achievements in 1999 are summarised

  17. Dissolution of LMFBR fuel-sodium aerosols

    International Nuclear Information System (INIS)

    Aerosols of either LMFBR fuel or PuO2 are essentially insoluble in water or biological fluids. If either of these aerosols is exposed to sodium metal vapor, the resulting aerosol is much more soluble in aqueous solutions. Preferential dissolution of uranium from mixed sodium-fuel aerosols makes the plutonium more readily soluble than for sodium-PuO2 aerosol. Ultrafiltration of the dissolution test solvent revealed the plutonium to be associated with particles between 2 nm and 10 nm in diameter, in both cases

  18. Contribution of methane to aerosol carbon mass

    Science.gov (United States)

    Bianchi, F.; Barmet, P.; Stirnweis, L.; El Haddad, I.; Platt, S. M.; Saurer, M.; Lötscher, C.; Siegwolf, R.; Bigi, A.; Hoyle, C. R.; DeCarlo, P. F.; Slowik, J. G.; Prévôt, A. S. H.; Baltensperger, U.; Dommen, J.

    2016-09-01

    Small volatile organic compounds (VOC) such as methane (CH4) have long been considered non-relevant to aerosol formation due to the high volatility of their oxidation products. However, even low aerosol yields from CH4, the most abundant VOC in the atmosphere, would contribute significantly to the total particulate carbon budget. In this study, organic aerosol (OA) mass yields from CH4 oxidation were evaluated at the Paul Scherrer Institute (PSI) smog chamber in the presence of inorganic and organic seed aerosols. Using labeled 13C methane, we could detect its oxidation products in the aerosol phase, with yields up to 0.09

  19. KfK Laboratory for Aerosol Physics and Filter Technology. Progress report and development activities in 1990

    International Nuclear Information System (INIS)

    The activities undertaken by the laboratory for aerosol physics and filter technology (LAF) in 1990 under the following projects are described: (1) nuclear safety research (safety and material problems of fast breeders, IWR-oriented safety research); (2) pollutant control in the environment (communal waste management, emission-reducing processes, climate research - pollutants' behaviour in the atmosphere), and (3) radioactive waste management (basic work on reprocessing technologies). The annex lists the publications by the LAF staff. (BBR)

  20. Nuclear waste

    International Nuclear Information System (INIS)

    Radioactive waste at U.S. nuclear power plants is mounting at a rate of more than 2,000 metric tons a year. Yet the Department of Energy (DOE) does not expect a geologic repository to be available before 2010. In response to concerns about how best to store the waste until a repository is available, GAO reviewed the alternatives of continued storage at utilities' reactor sites or transferring waste to a monitored retrievable storage facility. This paper assesses the likelihood of a monitored retrievable storage facility operating by 1990, legal implications if DOE is unable to take delivery of wastes in 1998, propriety of using the Nuclear Waste Fund from which DOE's waste program costs are paid to pay utilities for on-site storage capacity added after 1998, the ability of utilities to store their waste on-site until a repository is operating, and relative costs and safety of the two storage alternatives

  1. Charge distributions and coagulation of radioactive aerosols

    International Nuclear Information System (INIS)

    The self-charging of radioactive aerosols will be reduced by background ions, such as those produced by radioactive gases. The sources of these background ions and their production rates are specified for a reactor containment atmosphere during a possible nuclear accident. Previous theory is extended to calculate the charging of a polydisperse radioactive aerosol. Gaussian approximations to charge distributions on an aerosol of a given size, and are shown to give a good representation of the exact numerical charge distributions of a Cs aerosol at normal temperatures, and also for highly radioactive aerosol containing 131I in a containment atmosphere. Extensive calculations are performed for charged-induced modifications to Brownian coagulation rates between steady-state size distribution of these radioactive aerosols, and also between small-sized radioactive aerosol and larger (non-radioactive) aerosol. The results show considerable enhancements of the coagulation rates between large and small-sized aerosol, but also a strong suppression of coagulation between large particles. Rate modifications calculated using the Gaussian approximations are generally close to the exact values. Time-dependent calculations for a monodisperse α-decaying aerosol reveal enhancements in coagulation rates even when the average charge on the aerosol is positive. Our results are relevant to behaviour in a dusty plasma. (author)

  2. The effects of aerosols on climate

    International Nuclear Information System (INIS)

    Atmospheric aerosols (fine particles suspended in the atmosphere) can play two roles in the Earth’s radiation budget. In cloud-free air, aerosols scatter sunlight, some of which is reflected back to space (direct effect). Aerosols also determine the microphysical and optical properties of clouds (indirect effect). Whereas changes in natural aerosols are probably small during the last 100 years, there has been a large increase in the concentration of anthropogenic aerosols. The magnitude of their radiative effects is still very uncertain but seems to be sufficient to mask part of the global warming expected to stem from anthropogenic greenhouse gases. This paper presents the physical mechanisms of aerosol influence on climate. We then estimate the anthropogenic aerosol radiative effects and assess the climate response to these perturbations. (author)

  3. A statistical-numerical aerosol parameterization scheme

    Directory of Open Access Journals (Sweden)

    J.-P. Chen

    2013-05-01

    Full Text Available A new modal aerosol parameterization scheme, Statistical-Numerical Aerosol Parameterization (SNAP, was developed for studying aerosol processes and aerosol-cloud interactions in regional or global models. SNAP applies statistical fitting on numerical results to generate accurate parameterization formulas without sacrificing details of the growth kernel. Processes considered in SNAP include fundamental aerosol processes, as well as processes related to aerosol-cloud interactions. Comparison of SNAP with numerical solutions, analytical solutions, and binned aerosol model simulations showed that the new method performs well, with accuracy higher than that of the high-order numerical quadrature technique, at much less computation time. The SNAP scheme has been implemented in regional air quality models, producing results very close to those using binned-size schemes or numerical quadrature schemes.

  4. Review of models applicable to accident aerosols

    International Nuclear Information System (INIS)

    Estimations of potential airborne-particle releases are essential in safety assessments of nuclear-fuel facilities. This report is a review of aerosol behavior models that have potential applications for predicting aerosol characteristics in compartments containing accident-generated aerosol sources. Such characterization of the accident-generated aerosols is a necessary step toward estimating their eventual release in any accident scenario. Existing aerosol models can predict the size distribution, concentration, and composition of aerosols as they are acted on by ventilation, diffusion, gravity, coagulation, and other phenomena. Models developed in the fields of fluid mechanics, indoor air pollution, and nuclear-reactor accidents are reviewed with this nuclear fuel facility application in mind. The various capabilities of modeling aerosol behavior are tabulated and discussed, and recommendations are made for applying the models to problems of differing complexity

  5. Optical trapping of gold aerosols

    DEFF Research Database (Denmark)

    Schmitt, Regina K.; Pedersen, Liselotte Jauffred; Taheri, S. M.;

    2015-01-01

    Aerosol trapping has proven challenging and was only recently demonstrated.1 This was accomplished by utilizing an air chamber designed to have a minimum of turbulence and a laser beam with a minimum of aberration. Individual gold nano-particles with diameters between 80 nm and 200 nm were trappe...

  6. Saving Joint with Aerosol physics

    International Nuclear Information System (INIS)

    Full text: Using electro spray method to analyze wear debris from artificial joints. Well known aerosol techniques have been applied to determine the size distribution and concentration of wear particles found in joint fluids. The organic fraction (cells and large molecules) are removed by digestion. Knowing these data the risk of clogging of blood vessels can be medicinally reduced. (author)

  7. Immunization by a bacterial aerosol.

    Science.gov (United States)

    Garcia-Contreras, Lucila; Wong, Yun-Ling; Muttil, Pavan; Padilla, Danielle; Sadoff, Jerry; Derousse, Jessica; Germishuizen, Willem Andreas; Goonesekera, Sunali; Elbert, Katharina; Bloom, Barry R; Miller, Rich; Fourie, P Bernard; Hickey, Anthony; Edwards, David

    2008-03-25

    By manufacturing a single-particle system in two particulate forms (i.e., micrometer size and nanometer size), we have designed a bacterial vaccine form that exhibits improved efficacy of immunization. Microstructural properties are adapted to alter dispersive and aerosol properties independently. Dried "nanomicroparticle" vaccines possess two axes of nanoscale dimensions and a third axis of micrometer dimension; the last one permits effective micrometer-like physical dispersion, and the former provides alignment of the principal nanodimension particle axes with the direction of airflow. Particles formed with this combination of nano- and micrometer-scale dimensions possess a greater ability to aerosolize than particles of standard spherical isotropic shape and of similar geometric diameter. Here, we demonstrate effective application of this biomaterial by using the live attenuated tuberculosis vaccine bacille Calmette-Guérin (BCG). Prepared as a spray-dried nanomicroparticle aerosol, BCG vaccine exhibited high-efficiency delivery and peripheral lung targeting capacity from a low-cost and technically simple delivery system. Aerosol delivery of the BCG nanomicroparticle to normal guinea pigs subsequently challenged with virulent Mycobacterium tuberculosis significantly reduced bacterial burden and lung pathology both relative to untreated animals and to control animals immunized with the standard parenteral BCG. PMID:18344320

  8. Climatic impacts of anthropogenic aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Iversen, T. [Oslo Univ. (Norway)

    1996-03-01

    This paper was read at the workshop ``The Norwegian Climate and Ozone Research Programme`` held on 11-12 March 1996. Anthropogenic production of aerosols is mainly connected with combustion of fossil fuel. Measured by particulate mass, the anthropogenic sulphate production is the dominating source of aerosols in the Northern Hemisphere. Particles emitted in mechanical processes, fly ash etc. are less important because of their shorter atmospheric residence time. Possible climatological effects of anthropogenic aerosols are usually classified in two groups: direct and indirect. Direct effects are alterations of the radiative heating budget due to the aerosol particles in clear air. Indirect effects involve the interaction between particles and cloud processes. A simplified one-layer radiation model gave cooling in the most polluted mid-latitude areas and heating due to soot absorption in the Arctic. This differential trend in heating rates may have significant effects on atmospheric meridional circulations, which is important for the atmosphere as a thermodynamic system. Recently the description of sulphur chemistry in the hemispheric scale dispersion model has been improved and will be used in a model for Mie scattering and absorption

  9. Uncertainty quantification in aerosol dynamics

    International Nuclear Information System (INIS)

    The influence of uncertainty in coagulation and depositions mechanisms, as well as in the initial conditions, on the solution of the aerosol dynamic equation have been assessed using polynomial chaos theory. In this way, large uncertainties can be incorporated into the equations and their propagation as a function of space and time studied. We base our calculations on the simplified point model dynamic equation which includes coagulation and deposition removal mechanisms. Results are given for the stochastic mean aerosol density as a function of time as well as its variance. The stochastic mean and deterministic mean are shown to differ and the associated uncertainty, in the form of a sensitivity coefficient, is obtained as a function of time. In addition, we obtain the probability density function of the aerosol density and show how this varies with time. In view of the generally uncertain nature of an accidental aerosol release in a nuclear reactor accident, the polynomial chaos method is a particularly useful technique as it allows one to deal with a very large spread of input data and examine the effect this has on the quantities of interest. Convergence matters are studied and numerical values given.

  10. PIXE Analysis of Indoor Aerosols

    Science.gov (United States)

    Johnson, Christopher; Turley, Colin; Moore, Robert; Battaglia, Maria; Labrake, Scott; Vineyard, Michael

    2011-10-01

    We have performed a proton-induced X-ray emission (PIXE) analysis of aerosol samples collected in academic buildings at Union College to investigate the air quality in these buildings and the effectiveness of their air filtration systems. This is also the commissioning experiment for a new scattering chamber in the Union College Ion-Beam Analysis Laboratory. The aerosol samples were collected on Kapton foils using a nine-stage cascade impactor that separates particles according to their aerodynamic size. The foils were bombarded with beams of 2.2-MeV protons from the Union College 1.1-MV Pelletron Accelerator and the X-ray products were detected with an Amptek silicon drift detector. After subtracting the contribution from the Kapton foils, the X-ray energy spectra of the aerosol samples were analyzed using GUPIX software to determine the elemental concentrations of the samples. We will describe the collection of the aerosol samples, discuss the PIXE analysis, and present the results.

  11. Aerosol behaviour modeling and measurements

    International Nuclear Information System (INIS)

    Aerosol behavior within Liquid Metal Fast Breeder Reactor (LMFBR) containments is of critical importance since most of the radioactive species are expected to be associated with particulate forms and the mass of radiologically significant material leaked to the ambient atmosphere is directly related to the aerosol concentration airborne within the containment. Mathematical models describing the behavior of aerosols in closed environments, besides providing a direct means of assessing the importance of specific assumptions regarding accident sequences, will also serve as the basic tool with which to predict the consequences of various postulated accident situations. Consequently, considerable efforts have been recently directed toward the development of accurate and physically realistic theoretical aerosol behavior models. These models have accounted for various mechanisms affecting agglomeration rates of airborne particulate matter as well as particle removal rates from closed systems. In all cases, spatial variations within containments have been neglected and a well-mixed control volume has been assumed. Examples of existing computer codes formulated from the mathematical aerosol behavior models are the Brookhaven National Laboratory TRAP code, the PARDISEKO-II and PARDISEKO-III codes developed at Karlsruhe Nuclear Research Center, and the HAA-2, HAA-3, and HAA-3B codes developed by Atomics International. Because of their attractive short computation times, the HAA-3 and HAA-3B codes have been used extensively for safety analyses and are attractive candidates with which to demonstrate order of magnitude estimates of the effects of various physical assumptions. Therefore, the HAA-3B code was used as the nucleus upon which changes have been made to account for various physical mechanisms which are expected to be present in postulated accident situations and the latest of the resulting codes has been termed the HAARM-2 code. It is the primary purpose of the HAARM

  12. Aerosol Absorption Measurements in MILAGRO.

    Science.gov (United States)

    Gaffney, J. S.; Marley, N. A.; Arnott, W. P.; Paredes-Miranda, L.; Barnard, J. C.

    2007-12-01

    During the month of March 2006, a number of instruments were used to determine the absorption characteristics of aerosols found in the Mexico City Megacity and nearby Valley of Mexico. These measurements were taken as part of the Department of Energy's Megacity Aerosol Experiment - Mexico City (MAX-Mex) that was carried out in collaboration with the Megacity Interactions: Local and Global Research Observations (MILAGRO) campaign. MILAGRO was a joint effort between the DOE, NSF, NASA, and Mexican agencies aimed at understanding the impacts of a megacity on the urban and regional scale. A super-site was operated at the Instituto Mexicano de Petroleo in Mexico City (designated T-0) and at the Universidad Technologica de Tecamac (designated T-1) that was located about 35 km to the north east of the T-0 site in the State of Mexico. A third site was located at a private rancho in the State of Hidalgo approximately another 35 km to the northeast (designated T-2). Aerosol absorption measurements were taken in real time using a number of instruments at the T-0 and T-1 sites. These included a seven wavelength aethalometer, a multi-angle absorption photometer (MAAP), and a photo-acoustic spectrometer. Aerosol absorption was also derived from spectral radiometers including a multi-filter rotating band spectral radiometer (MFRSR). The results clearly indicate that there is significant aerosol absorption by the aerosols in the Mexico City megacity region. The absorption can lead to single scattering albedo reduction leading to values below 0.5 under some circumstances. The absorption is also found to deviate from that expected for a "well-behaved" soot anticipated from diesel engine emissions, i.e. from a simple 1/lambda wavelength dependence for absorption. Indeed, enhanced absorption is seen in the region of 300-450 nm in many cases, particularly in the afternoon periods indicating that secondary organic aerosols are contributing to the aerosol absorption. This is likely due

  13. Impact of the modal aerosol scheme GLOMAP-mode on aerosol forcing in the Hadley Centre Global Environmental Model

    OpenAIRE

    Bellouin, N; Mann, G.W.; Woodhouse, M.T.; Johnson, C.; Carslaw, K. S.; Dalvi, M.

    2012-01-01

    The Hadley Centre Global Environmental Model (HadGEM) includes two aerosol schemes: the Coupled Large-scale Aerosol Simulator for Studies in Climate (CLASSIC), and the new Global Model of Aerosol Processes (GLOMAP-mode). GLOMAP-mode is a modal aerosol microphysics scheme that simulates not only aerosol mass but also aerosol number, represents internally-mixed particles, and includes aerosol microphysical processes such as nucleation. In this study, both schemes provide hindcast simulations of...

  14. Composition and physical properties of the Asian Tropopause Aerosol Layer and the North American Tropospheric Aerosol Layer

    OpenAIRE

    Yu, P.; Toon, OB; Neely, RR; Martinsson, BG; Brenninkmeijer, CAM

    2015-01-01

    Recent studies revealed layers of enhanced aerosol scattering in the upper troposphere and lower stratosphere over Asia (Asian Tropopause Aerosol Layer (ATAL)) and North America (North American Tropospheric Aerosol Layer (NATAL)). We use a sectional aerosol model (Community Aerosol and Radiation Model for Atmospheres (CARMA)) coupled with the Community Earth System Model version 1 (CESM1) to explore the composition and optical properties of these aerosol layers. The observed aerosol extinctio...

  15. Aerosol classification by airborne high spectral resolution lidar observations

    Directory of Open Access Journals (Sweden)

    S. Groß

    2012-10-01

    Full Text Available During four aircraft field experiments with the DLR research aircraft Falcon in 1998 (LACE, 2006 (SAMUM-1 and 2008 (SAMUM-2 and EUCAARI, airborne High Spectral Resolution Lidar (HSRL and in situ measurements of aerosol microphysical and optical properties were performed. Altogether, the properties of six different aerosol types and aerosol mixtures – Saharan mineral dust, Saharan dust mixtures, Canadian biomass burning aerosol, African biomass burning aerosol, anthropogenic pollution aerosol, and marine aerosol have been studied. On the basis of this extensive HSRL data set, we present an aerosol classification scheme which is also capable to identify mixtures of different aerosol types. We calculated mixing lines that allowed us to determine the contributing aerosol types. The aerosol classification scheme was validated with in-situ measurements and backward trajectory analyses. Our results demonstrate that the developed aerosol mask is capable to identify complex stratifications with different aerosol types throughout the atmosphere.

  16. Industrial Waste

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund

    2011-01-01

    Industrial waste is waste from industrial production and manufacturing. Industry covers many industrial sectors and within each sector large variations are found in terms of which raw materials are used, which production technology is used and which products are produced. Available data on unit...... generation rates and material composition as well as determining factors are discussed in this chapter. Characterizing industrial waste is faced with the problem that often only a part of the waste is handled in the municipal waste system, where information is easily accessible. In addition part of the...... industrial waste may in periods, depending on market opportunities and prices, be traded as secondary rawmaterials. Production-specificwaste from primary production, for example steel slag, is not included in the current presentation. In some countries industries must be approved or licensed and as part of...

  17. Toxicity of atmospheric aerosols on marine phytoplankton

    Science.gov (United States)

    Paytan, A.; Mackey, K.R.M.; Chen, Y.; Lima, I.D.; Doney, S.C.; Mahowald, N.; Labiosa, R.; Post, A.F.

    2009-01-01

    Atmospheric aerosol deposition is an important source of nutrients and trace metals to the open ocean that can enhance ocean productivity and carbon sequestration and thus influence atmospheric carbon dioxide concentrations and climate. Using aerosol samples from different back trajectories in incubation experiments with natural communities, we demonstrate that the response of phytoplankton growth to aerosol additions depends on specific components in aerosols and differs across phytoplankton species. Aerosol additions enhanced growth by releasing nitrogen and phosphorus, but not all aerosols stimulated growth. Toxic effects were observed with some aerosols, where the toxicity affected picoeukaryotes and Synechococcus but not Prochlorococcus.We suggest that the toxicity could be due to high copper concentrations in these aerosols and support this by laboratory copper toxicity tests preformed with Synechococcus cultures. However, it is possible that other elements present in the aerosols or unknown synergistic effects between these elements could have also contributed to the toxic effect. Anthropogenic emissions are increasing atmospheric copper deposition sharply, and based on coupled atmosphere-ocean calculations, we show that this deposition can potentially alter patterns of marine primary production and community structure in high aerosol, low chlorophyll areas, particularly in the Bay of Bengal and downwind of South and East Asia.

  18. Waste indicators

    International Nuclear Information System (INIS)

    The Waste Indicator Project focuses on methods to evaluate the efficiency of waste management. The project proposes the use of three indicators for resource consumption, primary energy and landfill requirements, based on the life-cycle principles applied in the EDIP Project. Trial runs are made With the indicators on paper, glass packaging and aluminium, and two models are identified for mapping the Danish waste management, of which the least extensive focuses on real and potential savings. (au)

  19. Integral Waste

    OpenAIRE

    Cubitt, Sean

    2015-01-01

    It is not only the physical digital media that pile waste upon waste in an era of built-in obsolescence driven by over-production attempting to balance the falling rate of profit. Energy used in the manufacture, employment and recycling of devices belongs to a system where waste is not merely accidental but integral to the operation of cognitive capitalism. Oil and gas, uranium and hydroelectricity all prey disproportionately on indigenous peoples, who are turned into economic externalities a...

  20. Waste Management

    OpenAIRE

    Anonymous

    2006-01-01

    The Productivity Commission’s inquiry report into ‘Waste Management’ was tabled by Government in December 2006. The Australian Government asked the Commission to identify policies that would enable Australia to address market failures and externalities associated with the generation and disposal of waste, and recommend how resource efficiencies can be optimised to improve economic, environmental and social outcomes. In the final report, the Commission maintains that waste management policy sh...

  1. Waste indicators

    Energy Technology Data Exchange (ETDEWEB)

    Dall, O.; Lassen, C.; Hansen, E. [Cowi A/S, Lyngby (Denmark)

    2003-07-01

    The Waste Indicator Project focuses on methods to evaluate the efficiency of waste management. The project proposes the use of three indicators for resource consumption, primary energy and landfill requirements, based on the life-cycle principles applied in the EDIP Project. Trial runs are made With the indicators on paper, glass packaging and aluminium, and two models are identified for mapping the Danish waste management, of which the least extensive focuses on real and potential savings. (au)

  2. Radioactive Wastes.

    Science.gov (United States)

    Choudri, B S; Baawain, Mahad

    2015-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2014. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes. PMID:26420096

  3. Radioactive Wastes.

    Science.gov (United States)

    Choudri, B S; Baawain, Mahad

    2016-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2015. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes. PMID:27620100

  4. CCN activity of aliphatic amine secondary aerosol

    Directory of Open Access Journals (Sweden)

    X. Tang

    2014-01-01

    Full Text Available Aliphatic amines can form secondary aerosol via oxidation with atmospheric radicals (e.g. hydroxyl radical and nitrate radical. The particle composition can contain both secondary organic aerosol (SOA and inorganic salts. The fraction of organic to inorganic materials in the particulate phase influences aerosol hygroscopicity and cloud condensation nuclei (CCN activity. SOA formed from trimethylamine (TMA and butylamine (BA reactions with hydroxyl radical (OH is composed of organic material of low hygroscopicity (single hygroscopicity parameter, κ ≤ 0.25. Secondary aerosol formed from the tertiary aliphatic amine (TMA with N2O5 (source of nitrate radical, NO3, contains less volatile compounds than the primary aliphatic amine (BA aerosol. TMA + N2O5 form semi-volatile organics in low RH conditions that have κ ~ 0.20, indicative of slightly soluble organic material. As RH increases, several inorganic amine salts are formed as a result of acid-base reactions. The CCN activity of the humid TMA-N2O5 aerosol obeys Zdanovskii, Stokes, and Robinson (ZSR ideal mixing rules. Higher CCN activity (κ > 0.3 was also observed for humid BA+N2O5 aerosols compared with dry aerosol (κ ~ 0.2, as a result of the formation of inorganic salts such as NH4NO3 and butylamine nitrate (C4H11N · HNO3. Compared with TMA, BA+N2O5 reactions produce more volatile aerosols. The BA+N2O5 aerosol products under humid experiments were found to be very sensitive to the temperature within the stream-wise continuous flow thermal gradient CCN counter. The CCN counter, when set above a 21 °C temperature difference, evaporates BA+N2O5 aerosol formed at RH ≥ 30%; κ ranges from 0.4 to 0.7 and is dependent on the instrument supersaturation (ss settings. The aerosol behaves non-ideally, hence simple ZSR rules cannot be applied to the CCN results from the primary aliphatic amine system. Overall, aliphatic amine aerosol systems κ ranges from 0.2 < κ < 0.7. This work indicates that

  5. How We Can Constrain Aerosol Type Globally

    Science.gov (United States)

    Kahn, Ralph

    2016-01-01

    In addition to aerosol number concentration, aerosol size and composition are essential attributes needed to adequately represent aerosol-cloud interactions (ACI) in models. As the nature of ACI varies enormously with environmental conditions, global-scale constraints on particle properties are indicated. And although advanced satellite remote-sensing instruments can provide categorical aerosol-type classification globally, detailed particle microphysical properties are unobtainable from space with currently available or planned technologies. For the foreseeable future, only in situ measurements can constrain particle properties at the level-of-detail required for ACI, as well as to reduce uncertainties in regional-to-global-scale direct aerosol radiative forcing (DARF). The limitation of in situ measurements for this application is sampling. However, there is a simplifying factor: for a given aerosol source, in a given season, particle microphysical properties tend to be repeatable, even if the amount varies from day-to-day and year-to-year, because the physical nature of the particles is determined primarily by the regional environment. So, if the PDFs of particle properties from major aerosol sources can be adequately characterized, they can be used to add the missing microphysical detail the better sampled satellite aerosol-type maps. This calls for Systematic Aircraft Measurements to Characterize Aerosol Air Masses (SAM-CAAM). We are defining a relatively modest and readily deployable, operational aircraft payload capable of measuring key aerosol absorption, scattering, and chemical properties in situ, and a program for characterizing statistically these properties for the major aerosol air mass types, at a level-of-detail unobtainable from space. It is aimed at: (1) enhancing satellite aerosol-type retrieval products with better aerosol climatology assumptions, and (2) improving the translation between satellite-retrieved aerosol optical properties and

  6. Secondary organic aerosol formation from primary aliphatic amines with NO3 radical

    OpenAIRE

    Q. G. J. Malloy; Li Qi; B. Warren; Cocker III, D. R.; M. E. Erupe; Silva, P J

    2009-01-01

    Primary aliphatic amines are an important class of nitrogen containing compounds emitted from automobiles, waste treatment facilities and agricultural animal operations. A series of experiments conducted at the UC-Riverside/CE-CERT Environmental Chamber is presented in which oxidation of methylamine, ethylamine, propylamine, and butylamine with O3 and NO3 have been investigated. Very little aerosol formation is observed in the presence of O3 only. However, after addition of ...

  7. Secondary organic aerosol formation from primary aliphatic amines with NO3 radical

    OpenAIRE

    M. E. Erupe; Cocker III, D. R.; B. Warren; Li Qi; Q. G. J. Malloy; Silva, P J

    2008-01-01

    Primary aliphatic amines are an important class of nitrogen containing compounds found to be emitted from automobiles, waste treatment facilities and agricultural animal operations. A series of experiments conducted at the UC-Riverside/CE-CERT Environmental Chamber is presented in which oxidation of methylamine, ethylamine, propylamine, and butylamine with NO3 has been investigated. Very little aerosol formation is observed in the presence of O3 only. However, after addition of NO, and by ext...

  8. Secondary Organic Aerosol Formation from Primary Aliphatic Amines with Nitrate Radical

    OpenAIRE

    Q. G. J. Malloy; Qi, L; B. Warren; Cocker III, D. R.; M. E. Erupe; Silva, P J

    2009-01-01

    Primary aliphatic amines are an important class of nitrogen containing compounds emitted from automobiles, waste treatment facilities and agricultural animal operations. A series of experiments conducted at the UC-Riverside/CECERT Environmental Chamber is presented in which oxidation of methylamine, ethylamine, propylamine, and butylamine with O3 and NO3 have been investigated. Very little aerosol formation is observed in the presence of O3 only. However, after addition of NO, and by extensio...

  9. Beschrijving van een verdampings-condensatie aerosol generator voor de produktie van submicron aerosol

    NARCIS (Netherlands)

    Feijt; A.*; Meulen; A.van der

    1985-01-01

    Dit rapport is een handleiding voor een bedrijfszeker, routinematig gebruik van een zgn. Evaporation-Condensation aerosol Conditioner. Met deze aerosol generatie apparatuur kunnen op stabiele, reproduceerbare manier zeer hoge concentraties (tot 1 miljoen deeltjes per cc) monodispers submicron ae

  10. Periodicities in Aerosol Optical Depths

    CERN Document Server

    Ramachandran, S; Verma, Amit; Panigrahi, Prasanta K

    2011-01-01

    We investigate the temporal and spatial variability in aerosol optical depth (AOD) over different geographic locations in India due to their important role in the earth-atmosphere radiation budget. The use of continuous wavelet transform pinpoints the spatio-temporal non-stationarity of the periodic variations in the AOD depending on local factors. The optimal time-frequency localization ability of Morlet wavelet accurately isolates the periodic features in the different frequency domains, to study the variations in the dominant periods due to local effects. The origin of the effects on the periodic modulations is then related to physical phenomena of regional nature, which throws considerable light on the observed variations in aerosol optical depths. We also find the phase relationship between different locations and to identify the possible correlations between different geographic locations and related environmental variations.

  11. Photostimulated Aggregation of Metal Aerosols

    CERN Document Server

    Karpov, Sergei V

    2010-01-01

    The effect of optical radiation on the rate of aggregation of nanoscopic particles is studied in metal aerosols. It has been shown that under light exposure, polydisperse metal aerosols can aggregate up to two orders faster due to the size dependent photoelectron effect from nanoparticles. Different size nanoparticles undergo mutual heteropolar charging when exchanging photoelectrons through the interparticle medium to result in an increased rate of aggregation. It is shown that long-range electrostatic attractive forces drive the particles into closer distances where the short-range Van-der-Waals forces become dominating. Attention is drawn to the fact that this effect may occur in various types of dispersed systems as well as in natural heteroaerosols.

  12. Food waste or wasted food

    OpenAIRE

    van Graas, Maaike Helene

    2014-01-01

    In the industrialized world large amounts of food are daily disposed of. A significant share of this waste could be avoided if different choices were made by individual households. Each day, every household makes decisions to maximize their happiness while balancing restricted amounts of time and money. Thinking of the food waste issue in terms of the consumer choice problem where households can control the amount of wasted food, we can model how households can make the best decisions. I...

  13. A mathematical model of aerosol holding chambers

    DEFF Research Database (Denmark)

    Zak, M; Madsen, J; Berg, E;

    1999-01-01

    A mathematical model of aerosol delivery from holding chambers (spacers) was developed incorporating tidal volume (VT), chamber volume (Vch), apparatus dead space (VD), effect of valve insufficiency and other leaks, loss of aerosol by immediate impact on the chamber wall, and fallout of aerosol...... in the chamber with time. Four different spacers were connected via filters to a mechanical lung model, and aerosol delivery during "breathing" was determined from drug recovery from the filters. The formula correctly predicted the delivery of budesonide aerosol from the AeroChamber (Trudell Medical, London......-mentioned factors, initial loss of aerosol by impact on the chamber wall is most important for the efficiency of a spacer. With a VT of 195 mL, the AeroChamber and Babyhaler were emptied in two breaths, the NebuChamber in four breaths, and the Nebuhaler in six breaths. Insufficiencies of the expiratory valves were...

  14. Immunization by a bacterial aerosol

    OpenAIRE

    Garcia-Contreras, Lucila; Wong, Yun-Ling; Muttil, Pavan; Padilla, Danielle; Sadoff, Jerry; DeRousse, Jessica; Germishuizen, Willem Andreas; Goonesekera, Sunali; Elbert, Katharina; Bloom, Barry R.; Miller, Rich; Fourie, P. Bernard; Hickey, Anthony; Edwards, David

    2008-01-01

    By manufacturing a single-particle system in two particulate forms (i.e., micrometer size and nanometer size), we have designed a bacterial vaccine form that exhibits improved efficacy of immunization. Microstructural properties are adapted to alter dispersive and aerosol properties independently. Dried “nanomicroparticle” vaccines possess two axes of nanoscale dimensions and a third axis of micrometer dimension; the last one permits effective micrometer-like physical dispersion, and the form...

  15. Aerosol-cloud interaction inferred from MODIS satellite data and global aerosol models

    OpenAIRE

    G. Myhre; F. Stordal; M. Johnsrud; Y. J. Kaufman; D. Rosenfeld; Storelvmo, T.; Kristjansson, J. E.; Berntsen, T. K.; Myhre, A.; I. S. A. Isaksen

    2007-01-01

    We have used the MODIS satellite data and two global aerosol models to investigate the relationships between aerosol optical depth (AOD) and cloud parameters that may be affected by the aerosol concentration. The relationships that are studied are mainly between AOD, on the one hand, and cloud cover, cloud liquid water path, and water vapour, on the other. Additionally, cloud droplet effective radius, cloud optical depth, cloud top pressure and aerosol Ångström exponent, have been a...

  16. High resolution aerosol optical thickness retrieval over the Pearl River Delta region with improved aerosol modelling

    Institute of Scientific and Technical Information of China (English)

    WONG ManSing; NICHOL Janet; LEE Kwon Ho; LI ZhanQing

    2009-01-01

    Aerosol retrieval algorithms for the MODerate Resolution Imaging Spectroradiometer (MODIS) have been developed to estimate aerosol and microphysical properties of the atmosphere, which help to address aerosol climatic issues at global scale. However, higher spatial resolution aerosol products for urban areas have not been well researched mainly due to the difficulty of differentiating aerosols from bright surfaces in urban areas. Here, a new aerosol retrieval algorithm using the MODIS 500 m resolu-tion images is described, to retrieve aerosol properties over Hong Kong and the Pearl River Delta re-gion. The rationale of our technique is to first estimate the aerosol reflectance by decomposing the top-of-atmosphere reflectance from surface reflectance and Rayleigh path reflectance. For the deter-mination of surface reflectance, a modified Minimum Reflectance Technique (MRT) is used, and MRT images are computed for different seasons. A strong correlation is shown between the surface reflec-tance of MRT images and MODIS land surface reflectance products (MOD09), with a value of 0.9. For conversion of aerosol reflectance to Aerosol Optical Thickness (AOT), comprehensive Look Up Tables (LUT) are constructed, in which aerosol properties and sun-viewing geometry in the radiative transfer calculations are taken into account. Four aerosol types, namely mixed urban, polluted urban, dust, and heavy pollution, were derived using cluster analysis on three years of AERONET measurements in Hong Kong. Their aerosol properties were input for LUT calculation. The resulting 500 m AOT images are highly correlated (r=0.89) with AERONET sunphotometer observations in Hong Kong. This study demonstrates the applicability of aerosol retrieval at fine resolution scale in urban areas, which can assist the study of aerosol loading distribution and the impact of localized and transient pollution on urban air quality. In addition, the MODIS 500 m AOT images can be used to study cross

  17. High resolution aerosol optical thickness retrieval over the Pearl River Delta region with improved aerosol modelling

    Institute of Scientific and Technical Information of China (English)

    WONG; ManSing; NICHOL; Janet; LEE; Kwon; Ho

    2009-01-01

    Aerosol retrieval algorithms for the MODerate Resolution Imaging Spectroradiometer (MODIS) have been developed to estimate aerosol and microphysical properties of the atmosphere, which help to address aerosol climatic issues at global scale. However, higher spatial resolution aerosol products for urban areas have not been well researched mainly due to the difficulty of differentiating aerosols from bright surfaces in urban areas. Here, a new aerosol retrieval algorithm using the MODIS 500 m resolution images is described, to retrieve aerosol properties over Hong Kong and the Pearl River Delta region. The rationale of our technique is to first estimate the aerosol reflectance by decomposing the top-of-atmosphere reflectance from surface reflectance and Rayleigh path reflectance. For the determination of surface reflectance, a modified Minimum Reflectance Technique (MRT) is used, and MRT images are computed for different seasons. A strong correlation is shown between the surface reflectance of MRT images and MODIS land surface reflectance products (MOD09), with a value of 0.9. For conversion of aerosol reflectance to Aerosol Optical Thickness (AOT), comprehensive Look Up Tables (LUT) are constructed, in which aerosol properties and sun-viewing geometry in the radiative transfer calculations are taken into account. Four aerosol types, namely mixed urban, polluted urban, dust, and heavy pollution, were derived using cluster analysis on three years of AERONET measurements in Hong Kong. Their aerosol properties were input for LUT calculation. The resulting 500 m AOT images are highly correlated (r = 0.89) with AERONET sunphotometer observations in Hong Kong. This study demonstrates the applicability of aerosol retrieval at fine resolution scale in urban areas, which can assist the study of aerosol loading distribution and the impact of localized and transient pollution on urban air quality. In addition, the MODIS 500 m AOT images can be used to study cross

  18. Beschrijving van een verdampings-condensatie aerosol generator voor de produktie van submicron aerosol

    OpenAIRE

    Feijt; Meulen, van der, A.; De, A.

    1985-01-01

    Dit rapport is een handleiding voor een bedrijfszeker, routinematig gebruik van een zgn. Evaporation-Condensation aerosol Conditioner. Met deze aerosol generatie apparatuur kunnen op stabiele, reproduceerbare manier zeer hoge concentraties (tot 1 miljoen deeltjes per cc) monodispers submicron aerosol geproduceerd worden. De aerosol afmetingen kunnen gevarieerd worden tussen 0.3 en 1.2 mu-m in diameter de geometrische standaardafwijking bedraagt circa 1.25-1.4.

  19. Ice-condenser aerosol tests

    International Nuclear Information System (INIS)

    This report presents the results of an experimental investigation of aerosol particle transport and capture using a full-scale height and reduced-scale cross section test facility based on the design of the ice compartment of a pressurized water reactor (PWR) ice-condenser containment system. Results of 38 tests included thermal-hydraulic as well as aerosol particle data. Particle retention in the test section was greatly influenced by thermal-hydraulic and aerosol test parameters. Test-average decontamination factor (DF) ranged between 1.0 and 36 (retentions between ∼0 and 97.2%). The measured test-average particle retentions for tests without and with ice and steam ranged between DF = 1.0 and 2.2 and DF = 2.4 and 36, respectively. In order to apparent importance, parameters that caused particle retention in the test section in the presence of ice were steam mole fraction (SMF), noncondensible gas flow rate (residence time), particle solubility, and inlet particle size. Ice-basket section noncondensible flows greater than 0.1 m3/s resulted in stable thermal stratification whereas flows less than 0.1 m3/s resulted in thermal behavior termed meandering with frequent temperature crossovers between flow channels. 10 refs., 66 figs., 16 tabs

  20. Characterization of Aerosols Containing Microcystin

    Directory of Open Access Journals (Sweden)

    Lorraine C. Backer

    2007-10-01

    Full Text Available Toxic blooms of cyanobacteria are ubiquitous in both freshwater and brackishwater sources throughout the world. One class of cyanobacterial toxins, calledmicrocystins, is cyclic peptides. In addition to ingestion and dermal, inhalation is a likelyroute of human exposure. A significant increase in reporting of minor symptoms,particularly respiratory symptoms was associated with exposure to higher levels ofcyanobacteria during recreational activities. Algae cells, bacteria, and waterborne toxinscan be aerosolized by a bubble-bursting process with a wind-driven white-capped wavemechanism. The purposes of this study were to: evaluate sampling and analysis techniquesfor microcystin aerosol, produce aerosol droplets containing microcystin in the laboratory,and deploy the sampling instruments in field studies. A high-volume impactor and an IOMfilter sampler were tried first in the laboratory to collect droplets containing microcystins.Samples were extracted and analyzed for microcystin using an ELISA method. Thelaboratory study showed that cyanotoxins in water could be transferred to air via a bubble-bursting process. The droplets containing microcystins showed a bimodal size distributionwith the mass median aerodynamic diameter (MMAD of 1.4 and 27.8 μm. The samplingand analysis methods were successfully used in a pilot field study to measure microcystinaerosol in situ.

  1. Chromism of Model Organic Aerosol

    Science.gov (United States)

    Rincon, Angela; Guzman, Marcelo; Hoffmann, Michael; Colussi, Agustin

    2008-03-01

    The optical properties of the atmospheric aerosol play a fundamental role in the Earth's radiative balance. Since more than half of the aerosol mass consists of complex organic matter that absorbs in the ultraviolet and visible regions of the spectrum, it is important to establish the identity of the organic chromophores. Here we report studies on the chromism vs. chemical composition of photolyzed (lambda longer than 305 nm) solutions of pyruvic acid, a widespread aerosol component, under a variety of experimental conditions that include substrate concentration, temperature and the presence of relevant spectator solutes, such ammonium sulfate. We use high resolution mass- and 13C NMR-spectrometries to track chemical speciation in photolyzed solutions as they undergo thermochromic and photobleaching cycles. Since the chemical identity of the components of these mixtures does not change in these cycles, in which photobleached solutions gradually recover their yellow color in the dark with non-conventional kinetics typical of aggregation processes, we infer that visible absorptions likely involve the intermolecular coupling of carbonyl chromophores in supramolecular assemblies made possible by the polyfunctional nature of the products of pyruvic acid photolysis.

  2. Ice-condenser aerosol tests

    Energy Technology Data Exchange (ETDEWEB)

    Ligotke, M.W.; Eschbach, E.J.; Winegardner, W.K. (Pacific Northwest Lab., Richland, WA (United States))

    1991-09-01

    This report presents the results of an experimental investigation of aerosol particle transport and capture using a full-scale height and reduced-scale cross section test facility based on the design of the ice compartment of a pressurized water reactor (PWR) ice-condenser containment system. Results of 38 tests included thermal-hydraulic as well as aerosol particle data. Particle retention in the test section was greatly influenced by thermal-hydraulic and aerosol test parameters. Test-average decontamination factor (DF) ranged between 1.0 and 36 (retentions between {approximately}0 and 97.2%). The measured test-average particle retentions for tests without and with ice and steam ranged between DF = 1.0 and 2.2 and DF = 2.4 and 36, respectively. In order to apparent importance, parameters that caused particle retention in the test section in the presence of ice were steam mole fraction (SMF), noncondensible gas flow rate (residence time), particle solubility, and inlet particle size. Ice-basket section noncondensible flows greater than 0.1 m{sup 3}/s resulted in stable thermal stratification whereas flows less than 0.1 m{sup 3}/s resulted in thermal behavior termed meandering with frequent temperature crossovers between flow channels. 10 refs., 66 figs., 16 tabs.

  3. Initial steps of aerosol growth

    Directory of Open Access Journals (Sweden)

    O. Kulmala

    2004-09-01

    Full Text Available The formation and growth of atmospheric aerosols depend on several steps, namely nucleation, initial steps of growth and subsequent – mainly condensational – growth. This work focuses on the initial steps of growth, meaning the growth right after nucleation, where the interplay of curvature effects and thermodynamics has a significant role on the growth kinetics. More specifically, we investigate how ion clusters and aerosol particles grow from 1.5 nm to 20 nm in atmospheric conditions using experimental data obtained by air ion and aerosol spectrometers. The measurements have been performed at a boreal forest site in Finland. The observed trend that the growth rate seems to increase as a function of size can be used to investigate possible growth mechanisms. Such a growth rate is consistent with a recently suggested nano-Köhler mechanism, in which growth is activated at a certain size with respect to condensation of organic vapors. The results also imply that charge-enhance growth associated with ion-mediated nucleation plays only a minor role in the initial steps of growth, since it would imply a clear decrease of the growth rate with size. Finally, further evidence was obtained on the earlier suggestion that atmospheric nucleation and the subsequent growth of fresh nuclei are likely to be uncoupled phenomena via different participating vapors.

  4. Initial steps of aerosol growth

    Directory of Open Access Journals (Sweden)

    M. Kulmala

    2004-01-01

    Full Text Available The formation and growth of atmospheric aerosols depend on several steps, namely nucleation, initial steps of growth and subsequent – mainly condensational – growth. This work focuses on the initial steps of growth, meaning the growth right after nucleation, where the interplay of curvature effects and thermodynamics has a significant role on the growth kinetics. More specifically, we investigate how ion clusters and aerosol particles grow from 1.5 nm to 20 nm (diameter in atmospheric conditions using experimental data obtained by air ion and aerosol spectrometers. The measurements have been performed at a boreal forest site in Finland. The observed trend that the growth rate seems to increase as a function of size can be used to investigate possible growth mechanisms. Such a growth rate is consistent with a recently suggested nano-Köhler mechanism, in which growth is activated at a certain size with respect to condensation of organic vapors. The results also imply that charge-enhanced growth associated with ion-mediated nucleation plays only a minor role in the initial steps of growth, since it would imply a clear decrease of the growth rate with size. Finally, further evidence was obtained on the earlier suggestion that atmospheric nucleation and the subsequent growth of fresh nuclei are likely to be uncoupled phenomena via different participating vapors.

  5. Initial steps of aerosol growth

    Science.gov (United States)

    Kulmala, M.; Laakso, L.; Lehtinen, K. E. J.; Riipinen, I.; Dal Maso, M.; Anttila, T.; Kerminen, V.-M.; Hõrrak, U.; Vana, M.; Tammet, H.

    2004-12-01

    The formation and growth of atmospheric aerosols depend on several steps, namely nucleation, initial steps of growth and subsequent - mainly condensational - growth. This work focuses on the initial steps of growth, meaning the growth right after nucleation, where the interplay of curvature effects and thermodynamics has a significant role on the growth kinetics. More specifically, we investigate how ion clusters and aerosol particles grow from 1.5 nm to 20 nm (diameter) in atmospheric conditions using experimental data obtained by air ion and aerosol spectrometers. The measurements have been performed at a boreal forest site in Finland. The observed trend that the growth rate seems to increase as a function of size can be used to investigate possible growth mechanisms. Such a growth rate is consistent with a recently suggested nano-Köhler mechanism, in which growth is activated at a certain size with respect to condensation of organic vapors. The results also imply that charge-enhanced growth associated with ion-mediated nucleation plays only a minor role in the initial steps of growth, since it would imply a clear decrease of the growth rate with size. Finally, further evidence was obtained on the earlier suggestion that atmospheric nucleation and the subsequent growth of fresh nuclei are likely to be uncoupled phenomena via different participating vapors.

  6. Characterization of Sodium Spray Aerosols

    International Nuclear Information System (INIS)

    The consequences of pool and spray fires require evaluation in the safety analysis of liquid metal-cooled fast breeder reactors. Sodium spray fires are characterized by high temperature and pressure, produced during the rapid combustion of sodium in air. Following the initial energy release, some fraction of the reaction products are available as aerosols which follow the normal laws of agglomeration, growth, settling, and plating. An experimental study is underway at Atomics International to study the characteristics of high concentration sprays of liquid sodium in reduced oxygen atmospheres and in air. The experiments are conducted in a 31.5 ft3 (2 ft diam. by 10 ft high) vessel, certified for a pressure of 100 lb/in2 (gauge). The spray injection apparatus consists of a heated sodium supply pot and a spray nozzle through which liquid sodium is driven by nitrogen pressure. Spray rate and droplet size can be varied by the injection velocity (nozzle size, nitrogen pressure, and sodium temperature). Aerosols produced in 0, 4, and 10 vol. % oxygen environments have been studied. The concentration and particle size distribution of the material remaining in the air after the spray injection and reaction period are measured. Fallout rates are found to be proportional to the concentration of aerosol which remains airborne following the spray period. (author)

  7. Survival of virulent Legionella pneumophila in aerosols.

    OpenAIRE

    Hambleton, P.; Broster, M G; Dennis, P J; Henstridge, R.; Fitzgeorge, R.; Conlan, J W

    1983-01-01

    Aqueous suspensions of virulent Legionella pneumophila grown on solid medium retained virulence and aerosol survival characteristics for several months. Significant numbers of viable organisms were recovered from aerosols held at various relative humidities (r.h.) for up to 2 h. The organisms survived best at 65% r.h. and were least stable at 55% r.h. Exponential phase broth-grown organisms survived poorly in aerosols in comparison with stationary phase broth cultures or organisms grown on so...

  8. Atmospheric Aerosols at the MAGIC Site

    CERN Document Server

    Garrido, Daniel; Doro, Michele; Font, Lluís; López-Oramas, Alicia; Moralejo, Abelardo

    2013-01-01

    We investigate the performance of the MAGIC telescopes under three simulated atmospheric conditions: an increased aerosol content in the lower part of the troposphere, the presence of thin aerosol over-densities at different heights, and an extremely clean atmosphere. Weshow how the effective area of the telescope system is gradually reduced in the presence of varying concentrations of aerosols whereas the energy threshold rises. Clouds at different heights produce energy and altitude-dependent effects on the performance of the system.

  9. Inverse Modeling of Cloud – Aerosol Interactions

    OpenAIRE

    Partridge, Daniel

    2011-01-01

    The role of aerosols and clouds is one of the largest sources of uncertainty in understanding climate change. The primary scientific goal of this thesis is to improve the understanding of cloud-aerosol interactions by applying inverse modeling using Markov Chain Monte Carlo (MCMC) simulation. Through a set of synthetic tests using a pseudo-adiabatic cloud parcel model, it is shown that a self adaptive MCMC algorithm can efficiently find the correct optimal values of meteorological and aerosol...

  10. Microphysical Characterization of Aerosol Signatures over Greece

    OpenAIRE

    Akshath Sharma; Sampann Arora; Pranav Chandramouli; Costas Varotsos; Sat Ghosh; Archit Verma; Ishan Saini

    2016-01-01

    A detailed microphysical characterization is presented for aerosol spectra over three major areas over Greece, namely- the Area West of Crete (AWC), the Greater Thessaloniki area (GTA) and the Greater Athens Area (GAA) based on measurements made by Varotsos (2005). Aerosol size distributions along with cloud droplet concentrations were gathered from data collected from the Forward Scattering Spectrometer Probe (FSSP)-300 and Passive Cavity Aerosol Spectrometer Probe (PCASP)-100X flown on a Fa...

  11. Monodisperse Aerosol Particles in an Apartment

    Czech Academy of Sciences Publication Activity Database

    Ondráček, Jakub; Ondráčková, Lucie; Stavová, P.; Ždímal, Vladimír; Barták, M.; Smolík, Jiří

    Thessaloniki : Hellenic Association for Aerosol Research, 2008, T10A012P. [European Aerosol Conference 2008. Thessaloniki (GR), 24.08.2008-29.08.2008] R&D Projects: GA ČR GA101/07/1361 Institutional research plan: CEZ:AV0Z40720504 Keywords : indoor aerosols * dynamic characteristics * number size distribution Subject RIV: CF - Physical ; Theoretical Chemistry www.eac2008.org

  12. Pulmonary deposition and clearance of aerosolized interferon.

    OpenAIRE

    Wyde, P.R.; Wilson, S Z; M.J. Kramer; Sun, C S; Knight, V

    1984-01-01

    Small particle aerosols of a hybrid DNA recombinant human alpha interferon, A/D bgl, and a related DNA recombinant leukocyte interferon, A, were generated and delivered to mice for 23.5 h a day for 4 consecutive days. The antiviral activity of these interferons in delivery reservoirs, in the aerosols generated, and in the lungs of test mice was monitored during and after aerosol administration in cytopathic effect inhibition assays, using vesicular stomatitis virus as the indicator virus. In ...

  13. Nanoscale Polymeric Particles via Aerosol-Photopolymerization

    OpenAIRE

    Akgün, Ertan

    2015-01-01

    This PhD thesis focuses on the process of aerosol-photopolymerization for the generation of various polymeric particles. Such structures are most often prepared by liquid-based methods via the well-established thermal initiation step, and aerosol-photopolymerization is presented as an alternative, aerosol-based technique which employs photoinitiated polymerization. Discussed within this thesis are the advantages and broad aspects of the process.

  14. Waste Disposal

    International Nuclear Information System (INIS)

    This contribution describes the main activities of the Waste and Disposal Department of the Belgian Nuclear Research Center SCK-CEN. Achievements in 1997 in three topical areas are reported on: performance assessments, waste forms/packages and near-and far field studies

  15. Aerosol from Organic Nitrogen in the Southeast United States

    Science.gov (United States)

    Biogenic volatile organic compounds (BVOCs) contribute significantly to organic aerosol in the southeastern United States. During the Southern Oxidant and Aerosol Study (SOAS), a portion of ambient organic aerosol was attributed to isoprene oxidation and organic nitrogen from BVO...

  16. Nuclear waste

    International Nuclear Information System (INIS)

    This chapter present a brief overview of the current situation of siting radioactive wastes. This is followed by an overview of various psychological approaches attempting to analyse public reactions to nuclear facilities. It will be argued that public reactions to nuclear waste factilities must be seen in the context of more general attitudes toward nuclear energy. The latter are not only based upon perceptions of the health and environmental risks but are built on values, and sets of attributes which need not be similar to the representations o the experts and policy-makers. The issue of siting nuclear waste facilities is also embedded in a wider moral and political domain. This is illustrated by the importance of equity issues in siting radioactive wastes. In the last section, the implications of the present line of argument for risk communication and public participation in decisions about siting radioactive wastes will be briefly discussed. (author). 49 refs

  17. Aerosol observation in Fengtai area, Beijing

    Institute of Scientific and Technical Information of China (English)

    Zengdong Liu; Jianguo Liu; Bei Wang; Fan Lu; Shuhua Huang; Dexia Wu; Daowen Han

    2008-01-01

    Measurements of aerosol number concentration and particulate matter with diameter less than 10μm (PM10) mass concentrations of urban background aerosols were performed in Fengtai area, Beijing in 2006. Black carbon (BC) was collected simultaneously from the ground and analyzed to determine the particulate matter components. To satisfy the interest in continuous monitoring of temporal and spatial distribution of aerosols, the relationship between extinction coefficient (visibility) measured by lidar remote sensing and the aerosol number concentration measured from the ground was derived by using statistical method. Vertical particle number concentration profile within the planetary boundary layer could be inversed through the lidar data as well as the statistical relation.

  18. The fifth Finnish national aerosol symposium

    International Nuclear Information System (INIS)

    The Fifth Finnish Aerosol Symposium was held June 1-3, 1993. Symposium is jointly organized by FAAR, Aerosol Technology Group of Technical Research Centre of Finland and Helsinki University, Department of Physics. Aerosols, the suspensions of solid and liquid particles and gases, are receiving increasing importance in many areas of science and technology. These include industrial hygiene, ambient and indoor air pollution, pollution control technologies, cloud physics, nuclear safety engineering, combustion science and engineering, clean manufacturing technologies and material processing. The importance of aerosol issues during the development of advanced fuel conversion and material processing technologies can be realized when looking at the numerous papers presented on these topics at the Symposium

  19. The boiling point of stratospheric aerosols.

    Science.gov (United States)

    Rosen, J. M.

    1971-01-01

    A photoelectric particle counter was used for the measurement of aerosol boiling points. The operational principle involves raising the temperature of the aerosol by vigorously heating a portion of the intake tube. At or above the boiling point, the particles disintegrate rather quickly, and a noticeable effect on the size distribution and concentration is observed. Stratospheric aerosols appear to have the same volatility as a solution of 75% sulfuric acid. Chemical analysis of the aerosols indicates that there are other substances present, but that the sulfate radical is apparently the major constituent.

  20. SPM analysis of single aerosol particles

    International Nuclear Information System (INIS)

    Aerosol samples were collected using Anderson cascade impact samplers and the dispersed single aerosol particles were embedded in thin PVDF films. A group of single aerosol particles distributed in an area of 180 μm x 150 μm was analyzed by the scanning proton microprobe (SPM). The distributions of 12 elements in the group were mapped with the three dimensional contour technique. Air pollution sources were then analyzed in some details. It is shown that analysis of the group of single aerosol particles by SPM may become a new approach to the study of air pollution

  1. A mathematical model of aerosol holding chambers

    DEFF Research Database (Denmark)

    Zak, M; Madsen, J; Berg, E;

    1999-01-01

    A mathematical model of aerosol delivery from holding chambers (spacers) was developed incorporating tidal volume (VT), chamber volume (Vch), apparatus dead space (VD), effect of valve insufficiency and other leaks, loss of aerosol by immediate impact on the chamber wall, and fallout of aerosol......-mentioned factors, initial loss of aerosol by impact on the chamber wall is most important for the efficiency of a spacer. With a VT of 195 mL, the AeroChamber and Babyhaler were emptied in two breaths, the NebuChamber in four breaths, and the Nebuhaler in six breaths. Insufficiencies of the expiratory valves were...

  2. The Aerosol/Cloud/Ecosystems Mission (ACE)

    Science.gov (United States)

    Schoeberl, Mark

    2008-01-01

    The goals and measurement strategy of the Aerosol/Cloud/Ecosystems Mission (ACE) are described. ACE will help to answer fundamental science questions associated with aerosols, clouds, air quality and global ocean ecosystems. Specifically, the goals of ACE are: 1) to quantify aerosol-cloud interactions and to assess the impact of aerosols on the hydrological cycle and 2) determine Ocean Carbon Cycling and other ocean biological processes. It is expected that ACE will: narrow the uncertainty in aerosol-cloud-precipitation interaction and quantify the role of aerosols in climate change; measure the ocean ecosystem changes and precisely quantify ocean carbon uptake; and, improve air quality forecasting by determining the height and type of aerosols being transported long distances. Overviews are provided of the aerosol-cloud community measurement strategy, aerosol and cloud observations over South Asia, and ocean biology research goals. Instruments used in the measurement strategy of the ACE mission are also highlighted, including: multi-beam lidar, multiwavelength high spectra resolution lidar, the ocean color instrument (ORCA)--a spectroradiometer for ocean remote sensing, dual frequency cloud radar and high- and low-frequency micron-wave radiometer. Future steps for the ACE mission include refining measurement requirements and carrying out additional instrument and payload studies.

  3. Limitation on electrical measures of aerosols

    International Nuclear Information System (INIS)

    Based upon the assumption that there is a constant, natural, background ion source, atmospheric conductivity has been used as a measure of the presence of aerosol particles because such particles remove the effective charge carriers from the atmosphere. Another variety of electrical measure is the total charge acquired by the aerosol under either natural or artificial charging conditions. Currently, the most widely cited electrical method for aerosol size distribution analysis is the diffusion charging mobility analysis method in which the electrical current due to the controlled unipolar charging of the aerosol is measured while increasing mobility fractions of that aerosol are removed. The hypothesis is that by monitoring the diminution of aerosol current as a function of the known particle electrical mobilities removed, a measure of the aerosol size distribution is derived. Fundamental to all such measures of aerosol size is the assumption that any aerosol can be put in a well-defined charge state. This note presents an examination of that assumption

  4. Topics in current aerosol research (part2)

    CERN Document Server

    Hidy, G M

    1972-01-01

    Topics in Current Aerosol Research, Part 2 contains some selected articles in the field of aerosol study. The chosen topics deal extensively with the theory of diffusiophoresis and thermophoresis. Also covered in the book is the mathematical treatment of integrodifferential equations originating from the theory of aerosol coagulation. The book is the third volume of the series entitled International Reviews in Aerosol Physics and Chemistry. The text offers significant understanding of the methods employed to develop a theory for thermophoretic and diffusiophoretic forces acting on spheres in t

  5. Is aerosol formation in cirrus clouds possible?

    Directory of Open Access Journals (Sweden)

    J. Kazil

    2007-01-01

    Full Text Available The recent observation of ultrafine aerosol particles in cirrus clouds has raised the question whether aerosol formation within cirrus clouds is possible, and if so, what mechanisms are involved. We have developed an aerosol parcel model of neutral and charged H2SO4/H2O aerosol processes, including nucleation from the gas phase and loss onto cirrus ice particles. Laboratory thermodynamic data for sulfuric acid uptake and loss by small neutral and charged clusters are used, allowing for a reliable description of both neutral and charged nucleation down to the very low temperatures occurring in the upper troposphere and lower stratosphere. The model implements a first order scheme for resolving the aerosol size distribution within its geometric size sections, which efficiently suppresses numerical diffusion. We operate the model offline on trajectories generated with a detailed 1D cirrus model which describes ice crystal nucleation, deposition growth, vertical advection of ice crystals and water vapor, and ice crystal sedimentation. In this paper we explore the possibility of aerosol formation within non-convective cirrus clouds and draw conclusions for aerosol formation in anvil cirrus. We find that sulfate aerosol formation within cirrus clouds can proceed even at high ice surface area concentrations, and depends strongly on the size of the cirrus ice crystals and on the surface area concentration of preexisting aerosol particles.

  6. SMEX02 Atmospheric Aerosol Optical Properties Data

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of observations of atmospheric parameters including spectral aerosol optical depths, precipitable water, sky radiance distributions and...

  7. Detailed Aerosol Characterization using Polarimetric Measurements

    Science.gov (United States)

    Hasekamp, Otto; di Noia, Antonio; Stap, Arjen; Rietjens, Jeroen; Smit, Martijn; van Harten, Gerard; Snik, Frans

    2016-04-01

    Anthropogenic aerosols are believed to cause the second most important anthropogenic forcing of climate change after greenhouse gases. In contrast to the climate effect of greenhouse gases, which is understood relatively well, the negative forcing (cooling effect) caused by aerosols represents the largest reported uncertainty in the most recent assessment of the International Panel on Climate Change (IPCC). To reduce the large uncertainty on the aerosol effects on cloud formation and climate, accurate satellite measurements of aerosol optical properties (optical thickness, single scattering albedo, phase function) and microphysical properties (size distribution, refractive index, shape) are essential. There is growing consensus in the aerosol remote sensing community that multi-angle measurements of intensity and polarization are essential to unambiguously determine all relevant aerosol properties. This presentations adresses the different aspects of polarimetric remote sensing of atmospheric aerosols, including retrieval algorithm development, validation, and data needs for climate and air quality applications. During past years, at SRON-Netherlands Instite for Space Research retrieval algorithms have been developed that make full use of the capabilities of polarimetric measurements. We will show results of detailed aerosol properties from ground-based- (groundSPEX), airborne- (NASA Research Scanning Polarimeter), and satellite (POLDER) measurements. Also we will discuss observational needs for future instrumentation in order to improve our understanding of the role of aerosols in climate change and air quality.

  8. Multi-Sensor Aerosol Products Sampling System

    Science.gov (United States)

    Petrenko, M.; Ichoku, C.; Leptoukh, G.

    2011-01-01

    Global and local properties of atmospheric aerosols have been extensively observed and measured using both spaceborne and ground-based instruments, especially during the last decade. Unique properties retrieved by the different instruments contribute to an unprecedented availability of the most complete set of complimentary aerosol measurements ever acquired. However, some of these measurements remain underutilized, largely due to the complexities involved in analyzing them synergistically. To characterize the inconsistencies and bridge the gap that exists between the sensors, we have established a Multi-sensor Aerosol Products Sampling System (MAPSS), which consistently samples and generates the spatial statistics (mean, standard deviation, direction and rate of spatial variation, and spatial correlation coefficient) of aerosol products from multiple spacebome sensors, including MODIS (on Terra and Aqua), MISR, OMI, POLDER, CALIOP, and SeaWiFS. Samples of satellite aerosol products are extracted over Aerosol Robotic Network (AERONET) locations as well as over other locations of interest such as those with available ground-based aerosol observations. In this way, MAPSS enables a direct cross-characterization and data integration between Level-2 aerosol observations from multiple sensors. In addition, the available well-characterized co-located ground-based data provides the basis for the integrated validation of these products. This paper explains the sampling methodology and concepts used in MAPSS, and demonstrates specific examples of using MAPSS for an integrated analysis of multiple aerosol products.

  9. Simplified aerosol modeling for variational data assimilation

    Directory of Open Access Journals (Sweden)

    F. Chevallier

    2009-06-01

    Full Text Available We have developed a simplified aerosol model together with its tangent linear and adjoint versions for variational assimilation of aerosol optical depth with the aim to optimize aerosol emissions over the globe. The model was derived from the general circulation model LMDz; it groups together the 24 aerosol species simulated in LMDz into 4 species, namely gaseous precursors, fine mode aerosols, coarse mode desert dust and coarse mode sea salt. The emissions have been kept as in the original model. Modifications, however, were introduced in the computation of aerosol optical depth and in the processes of sedimentation, dry and wet deposition and sulfur chemistry to ensure consistency with the new set of species and their composition.

    The simplified model successfully manages to reproduce the main features of the aerosol distribution in LMDz. Differences between the original and simplified models are mainly associated to the new deposition and sedimentation velocities consistent with the definition of species in the simplified model and the simplification of the sulfur chemistry. Furthermore, simulated aerosol optical depth remains within the variability of AERONET observations for all aerosol types and all sites throughout most of the year.

    Sensitivity analyses with the tangent linear version show that the simplified sulfur chemistry is the dominant process responsible for the strong non-linearity of the model.

  10. Impact of Biomass Burning Aerosols on the Biosphere over Amazonia

    Science.gov (United States)

    Malavelle, F.; Haywood, J.; Mercado, L.; Folberth, G.; Bellouin, N.

    2014-12-01

    Biomass burning (BB) smoke from deforestation and the burning of agricultural waste emit a complex cocktail of aerosol particles and gases. BB emissions show a regional hotspot over South America on the edges of Amazonia. These major perturbations and impacts on surface temperature, surface fluxes, chemistry, radiation, rainfall, may have significant consequent impacts on the Amazon rainforest, the largest and most productive carbon store on the planet. There is therefore potential for very significant interaction and interplay between aerosols, clouds, radiation and the biosphere in the region. Terrestrial carbon production (i.e. photosynthesis) is intimately tied to the supply of photosynthetically active radiation (PAR - i.e. wavelengths between 300-690 nm). PAR in sufficient intensity and duration is critical for plant growth. However, if a decrease in total radiation is accompanied by an increase in the component of diffuse radiation, plant productivity may increase due to higher light use efficiency per unit of PAR and less photosynthetic saturation. This effect, sometimes referred as diffuse light fertilization effect, could have increased the global land carbon sink by approximately one quarter during the global dimming period and is expected to be a least as important locally. By directly interacting with radiation, BB aerosols significantly reduce the total amount of PAR available to plant canopies. In addition, BB aerosols also play a centre role in cloud formation because they provide the necessary cloud condensation nuclei, hence indirectly altering the water cycle and the components and quantity of PAR. In this presentation, we use the recent observations from the South American Biomass Burning Analysis (SAMBBA) to explore the impact of radiation changes on the carbon cycle in the Amazon region caused by BB emissions. A parameterisation of the impact of diffuse and direct radiation upon photosynthesis rates and net primary productivity in the

  11. Large-Scale Spray Releases: Additional Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, Richard C.; Gauglitz, Phillip A.; Burns, Carolyn A.; Fountain, Matthew S.; Shimskey, Rick W.; Billing, Justin M.; Bontha, Jagannadha R.; Kurath, Dean E.; Jenks, Jeromy WJ; MacFarlan, Paul J.; Mahoney, Lenna A.

    2013-08-01

    One of the events postulated in the hazard analysis for the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak event involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids that behave as a Newtonian fluid. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and in processing facilities across the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are mostly absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale testing. The small-scale testing and resultant data are described in Mahoney et al. (2012b), and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used

  12. Small-Scale Spray Releases: Additional Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Schonewill, Philip P.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, G. N.; Mahoney, Lenna A.; Tran, Diana N.; Burns, Carolyn A.; Kurath, Dean E.

    2013-08-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are largely absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale. The small-scale testing and resultant data are described in Mahoney et al. (2012b) and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used to mimic the

  13. A global aerosol classification algorithm incorporating multiple satellite data sets of aerosol and trace gas abundances

    Science.gov (United States)

    Penning de Vries, M. J. M.; Beirle, S.; Hörmann, C.; Kaiser, J. W.; Stammes, P.; Tilstra, L. G.; Tuinder, O. N. E.; Wagner, T.

    2015-09-01

    Detecting the optical properties of aerosols using passive satellite-borne measurements alone is a difficult task due to the broadband effect of aerosols on the measured spectra and the influences of surface and cloud reflection. We present another approach to determine aerosol type, namely by studying the relationship of aerosol optical depth (AOD) with trace gas abundance, aerosol absorption, and mean aerosol size. Our new Global Aerosol Classification Algorithm, GACA, examines relationships between aerosol properties (AOD and extinction Ångström exponent from the Moderate Resolution Imaging Spectroradiometer (MODIS), UV Aerosol Index from the second Global Ozone Monitoring Experiment, GOME-2) and trace gas column densities (NO2, HCHO, SO2 from GOME-2, and CO from MOPITT, the Measurements of Pollution in the Troposphere instrument) on a monthly mean basis. First, aerosol types are separated based on size (Ångström exponent) and absorption (UV Aerosol Index), then the dominating sources are identified based on mean trace gas columns and their correlation with AOD. In this way, global maps of dominant aerosol type and main source type are constructed for each season and compared with maps of aerosol composition from the global MACC (Monitoring Atmospheric Composition and Climate) model. Although GACA cannot correctly characterize transported or mixed aerosols, GACA and MACC show good agreement regarding the global seasonal cycle, particularly for urban/industrial aerosols. The seasonal cycles of both aerosol type and source are also studied in more detail for selected 5° × 5° regions. Again, good agreement between GACA and MACC is found for all regions, but some systematic differences become apparent: the variability of aerosol composition (yearly and/or seasonal) is often not well captured by MACC, the amount of mineral dust outside of the dust belt appears to be overestimated, and the abundance of secondary organic aerosols is underestimated in comparison

  14. Management of nuclear airborne wastes and tritium retention

    International Nuclear Information System (INIS)

    An overall review is presented of the outcome of the research activities that have been supported by the Community programme (shared cost action) for the last years in the field of management of nuclear airborne wastes. The kinds of waste dealt with originate essentially from the reprocessing of spent nuclear fuel and from certain treatment and conditioning processes of radioactive waste. Consideration is therefore given to the management of the volatile radionuclides Krypton-85, Iodine-129, Carbon-14 and tritium followed by that of nitric oxides and radioactive aerosols. (author)

  15. The relationship between aerosol and cloud drop number concentrations in a global aerosol microphysics model

    Directory of Open Access Journals (Sweden)

    K. J. Pringle

    2009-06-01

    Full Text Available Empirical relationships that link cloud droplet number (CDN to aerosol number or mass are commonly used to calculate global fields of CDN for climate forcing assessments. In this work we use a sectional global model of sulfate and sea-salt aerosol coupled to a mechanistic aerosol activation scheme to explore the limitations of this approach. We find that a given aerosol number concentration produces a wide range of CDN concentrations due to variations in the shape of the aerosol size distribution. On a global scale, the dependence of CDN on the size distribution results in regional biases in predicted CDN (for a given aerosol number. Empirical relationships between aerosol number and CDN are often derived from regional data but applied to the entire globe. In an analogous process, we derive regional "correlation-relations" between aerosol number and CDN and apply these regional relations to calculations of CDN on the global scale. The global mean percentage error in CDN caused by using regionally derived CDN-aerosol relations is 20 to 26%, which is about half the global mean percentage change in CDN caused by doubling the updraft velocity. However, the error is as much as 25–75% in the Southern Ocean, the Arctic and regions of persistent stratocumulus when an aerosol-CDN correlation relation from the North Atlantic is used. These regions produce much higher CDN concentrations (for a given aerosol number than predicted by the globally uniform empirical relations. CDN-aerosol number relations from different regions also show very different sensitivity to changing aerosol. The magnitude of the rate of change of CDN with particle number, a measure of the aerosol efficacy, varies by a factor 4. CDN in cloud processed regions of persistent stratocumulus is particularly sensitive to changing aerosol number. It is therefore likely that the indirect effect will be underestimated in these important regions.

  16. The relationship between aerosol and cloud drop number concentrations in a global aerosol microphysics model

    Directory of Open Access Journals (Sweden)

    K. J. Pringle

    2009-01-01

    Full Text Available Empirical relationships that link cloud droplet number (CDN to aerosol number or mass are commonly used to calculate global fields of CDN for climate forcing assessments. In this work we use a sectional global model of sulfate and sea-salt aerosol coupled to a mechanistic aerosol activation scheme to explore the limitations of this approach. We find that a given aerosol number concentration produces a wide range of CDN concentrations due to variations in the shape of the aerosol size distribution. On a global scale, the dependence of CDN on the size distribution results in regional biases in predicted CDN (for a given aerosol number. Empirical relationships between aerosol number and CDN are often derived from regional data but applied to the entire globe. In an analogous process, we derive regional "correlation-relations" between aerosol number and CDN and apply these regional relations to calculations of CDN on the global scale. The global mean percentage error in CDN caused by using regionally derived CDN-aerosol relations is 20 to 26%, which is about half the global mean percentage change in CDN caused by doubling the updraft velocity. However, the error is as much as 25–75% in the Southern Ocean, the Arctic and regions of persistent stratocumulus when an aerosol-CDN correlation relation from the North Atlantic is used. These regions produce much higher CDN concentrations (for a given aerosol number than predicted by the globally uniform empirical relations. CDN-aerosol number relations from different regions also show very different sensitivity to changing aerosol. The magnitude of the rate of change of CDN with particle number, a measure of the aerosol efficacy, varies by a factor 4. CDN in cloud processed regions of persistent stratocumulus is particularly sensitive to changing aerosol number. It is therefore likely that the indirect effect will be underestimated in these important regions.

  17. The correlative method of industrial aerosol express-diagnostic

    International Nuclear Information System (INIS)

    The main difficulty of industrial aerosol control is absence of real-time data analysis methods for measurement quantities of a specific aerosol (for example, radioactive particles, beryllium aerosols, etc. This report is an attempt to establish a new experimental method for control of industrial aerosol pollution. The main idea of the method is to determine correlation dependences among the aerosol particle size distributions and quantities of specific aerosol particles in industrial pollutions, for which real-time control is very difficult. The possibility of specific aerosol control is suggested by means of aerosol size control. (author)

  18. Observation of attachment ratio of fission products on solution aerosol

    International Nuclear Information System (INIS)

    Attachment behavior of fission products to solution aerosols has been observed to elucidate the role of chemical effects in the generation mechanism of fissionproduct aerosols. Primary aerosols generated from aqueous solution of sodium chloride or ammonium sulfate were passed through a fission-product chamber, and radioactive aerosols were generated by attaching fission products to the primary aerosol particles. Attachment ratios of the fission products on aerosols were estimated from activity measurements. It was found that the attachment ratio of the sodium chloride solution aerosol is larger than that of the ammonium sulfate solution aerosol. (author)

  19. Improved global aerosol datasets for 2008 from Aerosol_cci

    Science.gov (United States)

    Holzer-Popp, Thomas; de Leeuw, Gerrit

    2013-04-01

    Within the ESA Climate Change Initiative (CCI) the Aerosol_cci project has meanwhile produced and validated global datasets from AATSR, PARASOL, MERIS, OMI and GOMOS for the complete year 2008. Whereas OMI and GOMOS were used to derive absorbing aerosol index and stratospheric extinction profiles, respectively, Aerosol Optical Depth (AOD) and Angstrom coefficient were retrieved from the three nadir sensors. For AATSR three algorithms were applied. AOD validation was conducted against AERONET sun photometer observations also in comparison to MODIS and MISR datasets. Validation included level2 (pixel level) and level3 (gridded daily) datasets. Several validation metrices were used and in some cases developed further in order to comprehensively evaluate the capabilities and limitations of the datasets. The metrices include standard statistical quantities (bias, rmse, Pearson correlation, linear regression) as well as scoring approaches to quantitatively assess the spatial and temporal correlations against AERONET. Over open ocean also MAN data were used to better constrain the aerosol background, but in 2008 had limited coverage. The validation showed that the PARASOL (ocean only) and AATSR (land and ocean) datasets have improved significantly and now reach the quality level and sometimes even go beyond the level of MODIS and MISR. However, the coverage of these European datasets is weaker than the one of the NASA datasets due to smaller instrument swath width. The MERIS dataset provides better coverage but has lower quality then the other datasets. A detailed regional and seasonal analysis revealed the strengths and weaknesses of each algorithm. Also, Angstrom coefficient was validated and showed encouraging results (more detailed aerosol type information provided in particular from PARASOL was not yet evaluated further). Additionally, pixel uncertainties contained in each dataset were statistically assessed which showed some remaining issues but also the added value

  20. Disposal Of Waste Matter

    International Nuclear Information System (INIS)

    This book deals with disposal of waste matter management of soiled waste matter in city with introduction, definition of waste matter, meaning of management of waste matter, management system of waste matter, current condition in the country, collect and transportation of waste matter disposal liquid waste matter, industrial waste matter like plastic, waste gas sludge, pulp and sulfuric acid, recycling technology of waste matter such as recycling system of Black clawson, Monroe and Rome.

  1. Waste segregation

    International Nuclear Information System (INIS)

    A scoping study has been undertaken to determine the state-of-the-art of waste segregation technology as applied to the management of low-level waste (LLW). Present-day waste segregation practices were surveyed through a review of the recent literature and by means of personal interviews with personnel at selected facilities. Among the nuclear establishments surveyed were Department of Energy (DOE) laboratories and plants, nuclear fuel cycle plants, public and private laboratories, institutions, industrial plants, and DOE and commercially operated shallow land burial sites. These survey data were used to analyze the relationship between waste segregation practices and waste treatment/disposal processes, to assess the developmental needs for improved segregation technology, and to evaluate the costs and benefits associated with the implementation of waste segregation controls. This task was planned for completion in FY 1981. It should be noted that LLW management practices are now undergoing rapid change such that the technology and requirements for waste segregation in the near future may differ significantly from those of the present day. 8 figures

  2. Nuclear waste

    International Nuclear Information System (INIS)

    Radioactive waste is mounting at U.S. nuclear power plants at a rate of more than 2,000 metric tons a year. Pursuant to statute and anticipating that a geologic repository would be available in 1998, the Department of Energy (DOE) entered into disposal contracts with nuclear utilities. Now, however, DOE does not expect the repository to be ready before 2010. For this reason, DOE does not want to develop a facility for monitored retrievable storage (MRS) by 1998. This book is concerned about how best to store the waste until a repository is available, congressional requesters asked GAO to review the alternatives of continued storage at utilities' reactor sites or transferring waste to an MRS facility, GAO assessed the likelihood of an MRSA facility operating by 1998, legal implications if DOE is not able to take delivery of wastes in 1998, propriety of using the Nuclear Waste Fund-from which DOE's waste program costs are paid-to pay utilities for on-site storage capacity added after 1998, ability of utilities to store their waste on-site until a repository is operating, and relative costs and safety of the two storage alternatives

  3. Retrieval of Aerosol Height with TROPOMI

    Science.gov (United States)

    Sanders, A. F. J.; de Haan, J. F.; Veefkind, J. P.

    2012-04-01

    The Tropospheric Monitoring Instrument (TROPOMI), to be launched in 2015, will feature a new aerosol product providing the height of aerosol layers. Aerosol Layer Height will be one of two aerosol products, the other one being the Absorbing Aerosol Index. TROPOMI is a UV-VIS-NIR imaging spectrometer with daily global coverage. It will be part of ESA's Sentinel-5 Precursor mission. Algorithm development for the aerosol height product is currently underway at KNMI. In this presentation we will introduce the algorithm, highlight some of the development issues and discuss possible applications and example aerosol cases. Aerosol height observations from the near-infrared wavelength range will improve retrieval of other aerosol properties, particularly retrieval of absorption optical thickness. An increase in absorption in the ultraviolet wavelength range can be due to a higher imaginary part of the refractive index or to the aerosol layer being at a higher altitude. Independent height observations will therefore further constrain retrieval of the single scattering albedo. Furthermore, aerosol profile information is an important parameter when estimating radiative forcings and climate impacts of aerosol, it is a significant source of uncertainty in trace gas retrieval and it helps in understanding atmospheric transport mechanisms. Finally, timely available, global observations of aerosol height will be of interest to aviation safety agencies. The retrieval algorithm for aerosol height will be based on absorption by oxygen in the A-band (759-770 nm). Aerosols are assumed to be contained in a single layer. A spectral fit of reflectance (resolution 0.5 nm) across the absorption band provides layer height. The retrieval method will be optimal estimation to ensure a proper error analysis. Sensitivity studies have indicated that accuracy and precision of retrieved height for cloud-free scenes will be well below the TROPOMI science requirements (1 km). They have also shown that

  4. Characterization of aerosols produced by surgical procedures

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, H.C.; Muggenburg, B.A.; Lundgren, D.L.; Guilmette, R.A.; Snipes, M.B.; Jones, R.K. [Inhalation Toxicology Research Institute, Albuquerque, NM (United States); Turner, R.S. [Lovelace Health Systems, Albuquerque, NM (United States)

    1994-07-01

    In many surgeries, especially orthopedic procedures, power tools such as saws and drills are used. These tools may produce aerosolized blood and other biological material from bone and soft tissues. Surgical lasers and electrocautery tools can also produce aerosols when tissues are vaporized and condensed. Studies have been reported in the literature concerning production of aerosols during surgery, and some of these aerosols may contain infectious material. Garden et al. (1988) reported the presence of papilloma virus DNA in the fumes produced from laser surgery, but the infectivity of the aerosol was not assessed. Moon and Nininger (1989) measured the size distribution and production rate of emissions from laser surgery and found that particles were generally less than 0.5 {mu}m diameter. More recently there has been concern expressed over the production of aerosolized blood during surgical procedures that require power tools. In an in vitro study, the production of an aerosol containing the human immunodeficiency virus (HIV) was reported when power tools were used to cut tissues with blood infected with HIV. Another study measured the size distribution of blood aerosols produced by surgical power tools and found blood-containing particles in a number of size ranges. Health care workers are anxious and concerned about whether surgically produced aerosols are inspirable and can contain viable pathogens such as HIV. Other pathogens such as hepatitis B virus (HBV) are also of concern. The Occupational Safety and Health funded a project at the National Institute for Inhalation Toxicology Research Institute to assess the extent of aerosolization of blood and other tissues during surgical procedures. This document reports details of the experimental and sampling approach, methods, analyses, and results on potential production of blood-associated aerosols from surgical procedures in the laboratory and in the hospital surgical suite.

  5. Potential climatic effects of anthropogenic aerosols

    International Nuclear Information System (INIS)

    Aerosols act as part of the climate system through their influence on solar and terrestrial radiation. The effect of anthropogenic aerosols on the reduction of visibility is explored in this chapter. Elemental carbon has been identified as the most effective visibility-reducing species. Most of the visibility reduction is due to particles with diameter smaller than 2.5 μm. Studies indicate that sulfate is also a very important aerosol species that results in low visibility and high turbidity. Radiative properties such as aerosol single-scattering albedo values and absorption-to-backscatter ratios purported to produce warming or cooling effects of aerosols are discussed. It is concluded that aerosol clouds have a tendency to cool when they are over a low-albedo surface and have a tendency to warm when they are over high-albedo surfaces such as snow. Anthropogenic aerosols have a tendency to warm the earth's atmospheric system, based on calculations and assumed aerosol optical properties. However, this effect is somewhat offset by the absorption and re-emission into space of infrared terrestrial radiation. The net effect depends on the ratio of the absorption coefficients in the visible and infrared and also on the surface albedo. The effects on infrared radiation are documented for two anthropogenic aerosol sources in the United States, the Denver metropolitan area and power plant plumes in New Mexico, through calculations and measurements. Measured cooling rates within an aerosol plume are not sufficient to offset the warming rate due to absorption of short-wave radiation. Research indicates that anthropogenic aerosols can possibly cause local-scale warming of the atmosphere, but global-scale climatic effects remain an open question

  6. Nuclear waste

    International Nuclear Information System (INIS)

    This extract from the House of Commons Hansard publication for Wednesday 12th July 1995 considers the current debate on the desirability or otherwise of disposing of low level radioactive waste in landfill sites. It covers wastes generated both by the nuclear industry and by medical processes in local hospitals, and the transport of such waste from source to disposal site. The questions raised lead to a debate about plans to sell off commercially desirable aspects of the nuclear electric generation industry while leaving the costs associated with decommissioning of Magnox reactors as a liability on the public purse. (UK)

  7. Radioactive wastes

    International Nuclear Information System (INIS)

    The execution of the Brazilian nuclear power program involves the generation of radwastes, some of which must be isolated, for several centuries, from human activities and environment. The Materials Directory from National Nuclear Energy Commission (CNEN) organized a project in order to collect information concerning the waste disposal practices that may fulfill national technical-social-economic conditions and to recommend them, if requested, to the competent authorities. The paper provides general information concerning the waste producers, the project organization, the regions in Brazil that should be investigated in more detail during the site selection studies, as well as the preliminary conclusion in waste management area

  8. Remote sensing of aerosol in the terrestrial atmosphere from space: "AEROSOL-UA" mission

    Science.gov (United States)

    Yatskiv, Yaroslav; Milinevsky, Gennadi; Degtyarev, Alexander

    2016-07-01

    The distribution and properties of atmospheric aerosols on a global scale are not well known in terms of determination of their effects on climate. This mostly is due to extreme variability of aerosol concentrations, properties, sources, and types. Aerosol climate impact is comparable to the effect of greenhouse gases, but its influence is more difficult to measure, especially with respect to aerosol microphysical properties and the evaluation of anthropogenic aerosol effect. There are many satellite missions studying aerosol distribution in the terrestrial atmosphere, such as MISR/Terra, OMI/Aura, AVHHR, MODIS/Terra and Aqua, CALIOP/CALIPSO. To improve the quality of data and climate models, and to reduce aerosol climate forcing uncertainties, several new missions are planned. The gap in orbital instruments for studying aerosol microphysics has arisen after the Glory mission failed during launch in 2011. In this review paper, we describe several planned aerosol space missions, including the Ukrainian project AEROSOL-UA that will obtain the data using a multi-channel scanning polarimeter and wide-angle polarimetric camera. The mission is designed for remote sensing of the aerosol microphysics and cloud properties on a global scale.

  9. Aerosol retrieval algorithm for the characterization of local aerosol using MODIS L1B data

    International Nuclear Information System (INIS)

    Atmospheric aerosol plays an important role in radiation budget, climate change, hydrology and visibility. However, it has immense effect on the air quality, especially in densely populated areas where high concentration of aerosol is associated with premature death and the decrease of life expectancy. Therefore, an accurate estimation of aerosol with spatial distribution is essential, and satellite data has increasingly been used to estimate aerosol optical depth (AOD). Aerosol product (AOD) from Moderate Resolution Imaging Spectroradiometer (MODIS) data is available at global scale but problems arise due to low spatial resolution, time-lag availability of AOD product as well as the use of generalized aerosol models in retrieval algorithm instead of local aerosol models. This study focuses on the aerosol retrieval algorithm for the characterization of local aerosol in Hong Kong for a long period of time (2006-2011) using high spatial resolution MODIS level 1B data (500 m resolution) and taking into account the local aerosol models. Two methods (dark dense vegetation and MODIS land surface reflectance product) were used for the estimation of the surface reflectance over land and Santa Barbara DISORT Radiative Transfer (SBDART) code was used to construct LUTs for calculating the aerosol reflectance as a function of AOD. Results indicate that AOD can be estimated at the local scale from high resolution MODIS data, and the obtained accuracy (ca. 87%) is very much comparable with the accuracy obtained from other studies (80%-95%) for AOD estimation

  10. Atmospheric Aerosols in the Suburb of Prague

    Czech Academy of Sciences Publication Activity Database

    Matějková, Daniela; Ždímal, Vladimír; Schwarz, Jaroslav; Smolík, Jiří

    -: -, 2009, T051A30. [European Aerosol Conference 2009. Karlsruhe (DE), 06.09.2009-11.09.2009] Grant ostatní: MF CZ:(FI) 0049 Institutional research plan: CEZ:AV0Z40720504 Keywords : atmospheric aerosols * particle formation * particle size distribution Subject RIV: CF - Physical ; Theoretical Chemistry

  11. Automated mobility-classified-aerosol detector

    OpenAIRE

    Russell, Lynn M.; Flagan, Richard C.; Zhang, Shou-Hua

    2001-01-01

    An aerosol detection system for measuring particle number distribution with respect to particle dimension in an aerosol sample. The system includes an alternating dual-bag sampler, a radially classified differential mobility analyzer, and a condensation nucleus counter. Pressure variations in sampling are compensated by feedback control of volumetric flow rates using a plurality of flow control elements.

  12. Aerosols Processes in the CMAQ Adjoint

    Czech Academy of Sciences Publication Activity Database

    Turner, M.; Henze, D.; Hakami, A.; Zhao, S.; Resler, Jaroslav; Carmichael, G.; Stanier, C.; Baek, J.; Saide, P.; Sandu, A.; Russel, A.; Jeong, G.; Nenes, A.; Capps, S.; Percell, P.; Pinder, R.; Napelenok, S.; Pye, H.; Bash, J.; Chai, T.; Byun, D

    Davis: Air Quality Research Center, 2011. [IAMA 2011. International Aerosol Modeling Algorithms Conference /3./. Davis, 30.11.2011-02.12.2011] Institutional research plan: CEZ:AV0Z10300504 Keywords : air pollution * adjoint * aerosols Subject RIV: DG - Athmosphere Sciences, Meteorology http://dl.dropbox.com/u/41967626/IAMApresent/TURNER.pdf

  13. Aerosols in science, medicine and technology

    International Nuclear Information System (INIS)

    In the conference opening address the applications of aerosol science to everyday life are listed, e.g. air pollution, airborn infections, climatic and weather effects, industrial processes and toxicology. The need for more investment in research, education and teaching in aerosol science is stressed. (UK)

  14. Atmospheric aerosol light scattering and polarization peculiarities

    CERN Document Server

    Patlashenko, Zh I

    2015-01-01

    This paper considers environmental problems of natural and anthropogenic atmospheric aerosol pollution and its global and regional monitoring. Efficient aerosol investigations may be achieved by spectropolarimetric measurements. Specifically second and fourth Stokes parameters spectral dependencies carry information on averaged refraction and absorption indexes and on particles size distribution functions characteristics.

  15. Evaluation of MERRAero (MERRA Aerosol Reanalysis)

    Science.gov (United States)

    Buchard, Virginie; da Silva, Arlindo; Randles, Cynthia; Colarco, Peter; Darmenov, Anton; Govindaraju, Ravi

    2016-01-01

    This presentation focuses on MERRA Aerosol Reanalysis (MERRAero) which is the first aerosol reanalysis produced at GMAO. This presentation involve an overview of MERRAero. The evaluation of MERRAero absorption and the evaluation of MERRAero Surface PM 2.5 will also be discussed.

  16. Characterization of urban aerosol in Cork city (Ireland using aerosol mass spectrometry

    Directory of Open Access Journals (Sweden)

    M. Dall'Osto

    2013-05-01

    Full Text Available Ambient wintertime background urban aerosol in Cork city, Ireland, was characterized using aerosol mass spectrometry. During the three-week measurement study in 2009, 93% of the ca. 1 350 000 single particles characterized by an Aerosol Time-of-Flight Mass Spectrometer (TSI ATOFMS were classified into five organic-rich particle types, internally mixed to different proportions with elemental carbon (EC, sulphate and nitrate, while the remaining 7% was predominantly inorganic in nature. Non-refractory PM1 aerosol was characterized using a High Resolution Time-of-Flight Aerosol Mass Spectrometer (Aerodyne HR-ToF-AMS and was also found to comprise organic aerosol as the most abundant species (62%, followed by nitrate (15%, sulphate (9% and ammonium (9%, and chloride (5%. Positive matrix factorization (PMF was applied to the HR-ToF-AMS organic matrix, and a five-factor solution was found to describe the variance in the data well. Specifically, "hydrocarbon-like" organic aerosol (HOA comprised 20% of the mass, "low-volatility" oxygenated organic aerosol (LV-OOA comprised 18%, "biomass burning" organic aerosol (BBOA comprised 23%, non-wood solid-fuel combustion "peat and coal" organic aerosol (PCOA comprised 21%, and finally a species type characterized by primary extit{m/z}~peaks at 41 and 55, similar to previously reported "cooking" organic aerosol (COA, but possessing different diurnal variations to what would be expected for cooking activities, contributed 18%. Correlations between the different particle types obtained by the two aerosol mass spectrometers are also discussed. Despite wood, coal and peat being minor fuel types used for domestic space heating in urban areas, their relatively low combustion efficiencies result in a significant contribution to PM1 aerosol mass (44% and 28% of the total organic aerosol mass and non-refractory total PM1, respectively.

  17. Estimating marine aerosol particle volume and number from Maritime Aerosol Network data

    Directory of Open Access Journals (Sweden)

    A. M. Sayer

    2012-09-01

    Full Text Available As well as spectral aerosol optical depth (AOD, aerosol composition and concentration (number, volume, or mass are of interest for a variety of applications. However, remote sensing of these quantities is more difficult than for AOD, as it is more sensitive to assumptions relating to aerosol composition. This study uses spectral AOD measured on Maritime Aerosol Network (MAN cruises, with the additional constraint of a microphysical model for unpolluted maritime aerosol based on analysis of Aerosol Robotic Network (AERONET inversions, to estimate these quantities over open ocean. When the MAN data are subset to those likely to be comprised of maritime aerosol, number and volume concentrations obtained are physically reasonable. Attempts to estimate surface concentration from columnar abundance, however, are shown to be limited by uncertainties in vertical distribution. Columnar AOD at 550 nm and aerosol number for unpolluted maritime cases are also compared with Moderate Resolution Imaging Spectroradiometer (MODIS data, for both the present Collection 5.1 and forthcoming Collection 6. MODIS provides a best-fitting retrieval solution, as well as the average for several different solutions, with different aerosol microphysical models. The "average solution" MODIS dataset agrees more closely with MAN than the "best solution" dataset. Terra tends to retrieve lower aerosol number than MAN, and Aqua higher, linked with differences in the aerosol models commonly chosen. Collection 6 AOD is likely to agree more closely with MAN over open ocean than Collection 5.1. In situations where spectral AOD is measured accurately, and aerosol microphysical properties are reasonably well-constrained, estimates of aerosol number and volume using MAN or similar data would provide for a greater variety of potential comparisons with aerosol properties derived from satellite or chemistry transport model data. However, without accurate AOD data and prior knowledge of

  18. Global Aerosol Optical Models and Lookup Tables for the New MODIS Aerosol Retrieval over Land

    Science.gov (United States)

    Levy, Robert C.; Remer, Loraine A.; Dubovik, Oleg

    2007-01-01

    Since 2000, MODIS has been deriving aerosol properties over land from MODIS observed spectral reflectance, by matching the observed reflectance with that simulated for selected aerosol optical models, aerosol loadings, wavelengths and geometrical conditions (that are contained in a lookup table or 'LUT'). Validation exercises have showed that MODIS tends to under-predict aerosol optical depth (tau) in cases of large tau (tau greater than 1.0), signaling errors in the assumed aerosol optical properties. Using the climatology of almucantur retrievals from the hundreds of global AERONET sunphotometer sites, we found that three spherical-derived models (describing fine-sized dominated aerosol), and one spheroid-derived model (describing coarse-sized dominated aerosol, presumably dust) generally described the range of observed global aerosol properties. The fine dominated models were separated mainly by their single scattering albedo (omega(sub 0)), ranging from non-absorbing aerosol (omega(sub 0) approx. 0.95) in developed urban/industrial regions, to neutrally absorbing aerosol (omega(sub 0) approx.90) in forest fire burning and developing industrial regions, to absorbing aerosol (omega(sub 0) approx. 0.85) in regions of savanna/grassland burning. We determined the dominant model type in each region and season, to create a 1 deg. x 1 deg. grid of assumed aerosol type. We used vector radiative transfer code to create a new LUT, simulating the four aerosol models, in four MODIS channels. Independent AERONET observations of spectral tau agree with the new models, indicating that the new models are suitable for use by the MODIS aerosol retrieval.

  19. AEROSOL PARTICLE COLLECTOR DESIGN STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S; Richard Dimenna, R

    2007-09-27

    A computational evaluation of a particle collector design was performed to evaluate the behavior of aerosol particles in a fast flowing gas stream. The objective of the work was to improve the collection efficiency of the device while maintaining a minimum specified air throughput, nominal collector size, and minimal power requirements. The impact of a range of parameters was considered subject to constraints on gas flow rate, overall collector dimensions, and power limitations. Potential improvements were identified, some of which have already been implemented. Other more complex changes were identified and are described here for further consideration. In addition, fruitful areas for further study are proposed.

  20. AN OVERVIEW ON: PHARMACEUTICAL AEROSOLS

    Directory of Open Access Journals (Sweden)

    Lahkar Sunita

    2012-09-01

    Full Text Available Pulmonary drug delivery system is found to have a wide range of application in the treatment of illness as well as in the research field due to its beneficial effect over the other dosage form. It is used not only in treatment of illness of asthma and chronic obstructive pulmonary disease (COPD but also finds its application in the treatment of diseases like diabetes, angina pectoris. This review article deals with an overview of one of the pulmonary drug delivery system called pharmaceutical aerosols.

  1. Nuclear waste

    International Nuclear Information System (INIS)

    This book discusses the GAO's work on the Department of Energy's (DOE) Waste Isolation Pilot Plant (WIPP). As is known, DOE is seeking legislation permanently withdrawing the WIPP site, located on federal land near Carlsbad, New Mexico, from public use. Because DOE wants to begin storing a limited amount of nuclear waste in WIPP for tests, action on land withdrawal, either through legislation or administrative action by the Secretary of the Interior, is necessary to authorize such storage

  2. Influence of aerosol vertical distribution on radiative budget and climate

    Science.gov (United States)

    Nabat, Pierre; Michou, Martine; Saint-Martin, David; Watson, Laura

    2016-04-01

    Aerosols interact with shortwave and longwave radiation with ensuing consequences on radiative budget and climate. Aerosols are represented in climate models either using an interactive aerosol scheme including prognostic aerosol variables, or using climatologies, such as monthly aerosol optical depth (AOD) fields. In the first case, aerosol vertical distribution can vary rapidly, at a daily or even hourly scale, following the aerosol evolution calculated by the interactive scheme. On the contrary, in the second case, a fixed aerosol vertical distribution is generally imposed by climatological profiles. The objective of this work is to study the impact of aerosol vertical distribution on aerosol radiative forcing, with ensuing effects on climate. Simulations have thus been carried out using CNRM-CM, which is a global climate model including an interactive aerosol scheme representing the five main aerosol species (desert dust, sea-salt, sulfate, black carbon and organic matter). Several multi-annual simulations covering the past recent years are compared, including either the prognostic aerosol variables, or monthly AOD fields with different aerosol vertical distributions. In the second case, AOD fields directly come from the first simulation, so that all simulations have the same integrated aerosol loads. The results show that modifying the aerosol vertical distribution has a significant impact on radiative budget, with consequences on global climate. These differences, highlighting the importance of aerosol vertical distribution in climate models, probably come from the modification of atmospheric circulation induced by changes in the heights of the different aerosols. Besides, nonlinear effects in the superposition of aerosol and clouds reinforce the impact of aerosol vertical distribution, since aerosol radiative forcing depends highly upon the presence of clouds, and upon the relative vertical position of aerosols and clouds.

  3. Aerosol growth in the cover gas space

    International Nuclear Information System (INIS)

    An aerosol equation appropriate to the cover gas space is derived with a growth term specified by the total mass fluxes across the cavity. A relation between the maximum supersaturation reached in boundary layers and the aerosol number density and mean droplet size enables calculations to be made of the aerosol size distribution, the settling flux and mean aerosol density. Possible saturations are related to temperatures and sizes of nuclei which could induce heterogeneous nucleation, and it is concluded that nucleation is more likely to occur in the colder upper boundary layer. For a fixed saturation in this layer, the settling rate increases faster than the aerosol density with increase in pool temperature. (author)

  4. A statistical–numerical aerosol parameterization scheme

    Directory of Open Access Journals (Sweden)

    J.-P. Chen

    2013-10-01

    Full Text Available A new modal aerosol parameterization scheme, the statistical–numerical aerosol parameterization (SNAP, was developed for studying aerosol processes and aerosol–cloud interactions in regional or global models. SNAP applies statistical fitting on numerical results to generate accurate parameterization formulas without sacrificing details of the growth kernel. Processes considered in SNAP include fundamental aerosol processes as well as processes related to aerosol–cloud interactions. Comparison of SNAP with numerical solutions, analytical solutions, and binned aerosol model simulations showed that the new method performs well, with accuracy higher than that of the high-order numerical quadrature technique, and with much less computation time. The SNAP scheme has been implemented in regional air quality models, producing results very close to those using binned-size schemes or numerical quadrature schemes.

  5. Future options for aerosol delivery to children

    DEFF Research Database (Denmark)

    Bisgaard, H

    1999-01-01

    There is an increasing awareness of the importance of reliable aerosol delivery, with emphasis on the dose delivered to the lungs, optimal clinical control, cost-effectiveness, and safety in children. Dose prescription should relate to the expected lung dose rather than the factory-dispensed dose...... a proportional reduction in lung dose; hence, attention should be paid to reducing such dead space. Plastics in spacers cause a rapid loss of drug due to electrostatic attraction of the aerosol. The residence time of the aerosol, i.e., the time available for inhalation, is increased in nonelectrostatic spacers...... during inhalation and avoiding loss of aerosol during exhalation. An automatic device (AirPac) has been developed that transforms a dry-powder inhaler, Turbuhaler, into a spacer. In addition to the general advantages of spacer treatment, this device offers the advantage of a drug aerosol delivered...

  6. Beijing Olympics as an aerosol field experiment

    Science.gov (United States)

    Cermak, J.; Knutti, R.

    2009-05-01

    During the 2008 Olympic Summer Games, emission reductions were enforced in Beijing to improve air quality. Here we explore their effect on the regional aerosol load. We compare satellite-retrieved aerosol optical thickness (AOT) of that period with previous years, both in absolute terms and in a neural network approach taking into account the meteorological conditions. A statistically significant reduction of aerosol load is found in Beijing that decreases in magnitude and significance with increasing region size. Locally, the aerosol load (log(AOT)) was about 0.4 to 0.75 standard deviations below the levels expected for the prevailing meteorological situation. The small size of this effect relative to meteorological variability highlights the importance of regional aerosol transport.

  7. Multiple scattering in a dense aerosol atmosphere

    Directory of Open Access Journals (Sweden)

    S. Mukai

    2012-01-01

    Full Text Available This study was designed to develop an efficient algorithm to retrieve aerosol characteristics in aerosol events, which are associated with dense concentrations of aerosols in the atmosphere, such as a dust storm or a biomass burning plume. The idea of successive scattering of light is reviewed based on the theory of radiative transfer. Then derivation of the method of successive order of scattering (MSOS is interpreted in detail, and it is shown that MSOS is available for a simulation scheme in the dense radiation field being used to retrieve aerosol properties in the event with the high optical thickness. Finally our algorithms are practically applied for the biomass burning aerosol event over the Amazon using Aqua/MODIS data.

  8. Waste economy (waste utilization) in the CR

    OpenAIRE

    Urbanová, Ivana

    2011-01-01

    This Bachelor thesis is prepared as general overview of the Czech Republic waste economy. Waste economy is used as individual industrial segment. Bachelor thesis is focused especially on a total production of waste and communal waste, legislative restrictions connected with waste economy in Czech republic and comparison of Czech waste economy with other European Union countries and with Switzerland as well. The issue of decreasing of waste production and its safe and environmentally acceptabl...

  9. Parameters influencing the aerosol capture performance of the Submerged-Bed Scrubber

    Energy Technology Data Exchange (ETDEWEB)

    Ruecker, C.M.; Scott, P.A.

    1987-04-01

    The Submerged-Bed Scrubber (SBS) is a novel air cleaning device that has been investigated by Pacific Northwest Laboratory (PNL) for scrubbing off gases from liquid-fed ceramic melters used to vitrify high-level waste (HLW). The concept for the SBS was originally conceived at Hanford for emergency venting of a reactor containment building. The SBS was adapted for use as a quenching scrubber at PNL because it can cool the hot melter off gas as well as remove over 90% of the airborne particles, thus meeting the minimum particulate decontamination factor (DF) of 10 required of a primary scrubber. The experiments in this study showed that the submicron aerosol DF for the SBS can exceed 100 under certain conditions. A conventional device, the ejector-venturi scrubber (EVS), has been previously used in this application. The EVS also adequately cools the hot gases from the melter while exhibiting aerosol removal DFs in the range of 5 to 30. In addition to achieving higher DFs than the EVS, however, the SBS has the advantage of being a passive system, better suited to the remote environment of an HLW processing system. The objective of this study was to characterize the performance of the SBS and to improve the aerosol capture efficiency by modifying the operating procedure or the design. A partial factorial experimental matrix was completed to determine the main effects of aerosol solubility, inlet off-gas temperature, inlet off-gas flow rate, steam-to-air ratio, bed diameter and packing diameter on the particulate removal efficiency of the SBS. Several additional experiments were conducted to measure the influence of the inlet aerosol concentration and scrubbing-water concentration on aerosol-removal performance. 33 refs., 17 figs., 14 tabs.

  10. Parameters influencing the aerosol capture performance of the Submerged-Bed Scrubber

    International Nuclear Information System (INIS)

    The Submerged-Bed Scrubber (SBS) is a novel air cleaning device that has been investigated by Pacific Northwest Laboratory (PNL) for scrubbing off gases from liquid-fed ceramic melters used to vitrify high-level waste (HLW). The concept for the SBS was originally conceived at Hanford for emergency venting of a reactor containment building. The SBS was adapted for use as a quenching scrubber at PNL because it can cool the hot melter off gas as well as remove over 90% of the airborne particles, thus meeting the minimum particulate decontamination factor (DF) of 10 required of a primary scrubber. The experiments in this study showed that the submicron aerosol DF for the SBS can exceed 100 under certain conditions. A conventional device, the ejector-venturi scrubber (EVS), has been previously used in this application. The EVS also adequately cools the hot gases from the melter while exhibiting aerosol removal DFs in the range of 5 to 30. In addition to achieving higher DFs than the EVS, however, the SBS has the advantage of being a passive system, better suited to the remote environment of an HLW processing system. The objective of this study was to characterize the performance of the SBS and to improve the aerosol capture efficiency by modifying the operating procedure or the design. A partial factorial experimental matrix was completed to determine the main effects of aerosol solubility, inlet off-gas temperature, inlet off-gas flow rate, steam-to-air ratio, bed diameter and packing diameter on the particulate removal efficiency of the SBS. Several additional experiments were conducted to measure the influence of the inlet aerosol concentration and scrubbing-water concentration on aerosol-removal performance. 33 refs., 17 figs., 14 tabs

  11. Intercomparison test of various aerosol measurement techniques

    International Nuclear Information System (INIS)

    At the suggestion of the CONT group (Containment Loading and Response), which is a subgroup of the Safety Working Group of the Fast Reactor Coordinating Committee, a group of experts undertook a comparison of the techniques of sodium aerosol measurement used in various laboratories in the EC. The following laboratories took part in the exercise: CEN-Mol (Belgium), CEA-Cadarache (France), CEA-Fontenay-aux-Roses (France), KfK-Karlsruhe (Federal Republic of Germany), ENEA-Bologna (Italy), and UKAEA-Winfrith (United Kingdom). The objective of the aerosol measurement workshop was to assess the applicability and reliability of specific aerosol measuring instruments. Measurements performed with equipment from the participating laboratories were evaluated using a standard procedure. This enabled an estimate of the accuracy of the experimental data to be provided for the verification of aerosol codes. Thus these results can be used as input for the physical modelling of aerosol behaviour, and the work reported here is a contribution to the definition of the radioactive source term for severe accidents in LMFBRs. The aerosol experts participating in the exercise agreed to concentrate on the techniques of measuring aerosol particle size distributions. The tests were performed at the FAUNA test facility using the aerosol loop. A sodium spray fire, which provides a continuous aerosol source of variable concentration, was produced under open-loop conditions in this facility. Although the primary objective of the workshop was to determine the particle size distributions of the aerosols, measurements of the sodium mass concentration were also made

  12. Radioactive waste management

    International Nuclear Information System (INIS)

    This eighth chapter presents the radioactive wastes and waste disposal; classification of radioactive wastes; basis requests of the radioactive waste management; conditions for a radioactive waste disposal; registers and inventories; transport of radioactive wastes from a facility to another and the radioactive waste management plan

  13. Biological aerosol warner and analyser

    Science.gov (United States)

    Schlemmer, Harry; Kürbitz, Gunther; Miethe, Peter; Spieweck, Michael

    2006-05-01

    The development of an integrated sensor device BiSAM (Biological Sampling and Analysing Module) is presented which is designed for rapid detection of aerosol or dust particles potentially loaded with biological warfare agents. All functional steps from aerosol collection via immuno analysis to display of results are fully automated. The core component of the sensor device is an ultra sensitive rapid analyser PBA (Portable Benchtop Analyser) based on a 3 dimensional immuno filtration column of large internal area, Poly HRP marker technology and kinetic optical detection. High sensitivity despite of the short measuring time, high chemical stability of the micro column and robustness against interferents make the PBA an ideal tool for fielded sensor devices. It is especially favourable to combine the PBA with a bio collector because virtually no sample preparation is necessary. Overall, the BiSAM device is capable to detect and identify living micro organisms (bacteria, spores, viruses) as well as toxins in a measuring cycle of typically half an hour duration. In each batch up to 12 different tests can be run in parallel together with positive and negative controls to keep the false alarm rate low.

  14. Effect of an aerosol- reduction device on spreading infected aerosols during ultrasonic scaling

    Directory of Open Access Journals (Sweden)

    Ghalyani Isfahani P. Assistant Professor"

    2003-07-01

    Full Text Available Statement of Problem: Ultrasonic Scaling is one of the main sources of producing infected aerosols in dentistry. These aerosols are able to spread pathogens such as microorganisms associated with tuberculosis, conjunctivitis, influenza and other respiratory diseases, herpetic and other skin diseases, ADIS and hepatitis B."nPurpose: The aim of this study was to investigate the clinical effectiveness of an aerosol- reduction device attaching to ultrasonic scaler handpiece."nMaterials and Methods: In this experimental study 18 patients participated. Randomly, mandibular and maxillary quadrants of one side, in each subject, were scaled using an ultrasonic scaler with aerosol-reduction device for 5 minutes. After 30 minutes, another quadrant was scaled by ultrasonic scaler without aerosol- reduction device. In order to determine the effectiveness of aerosol- reduction device, blood agar plates attached to the surgical mask of the operator, 30 cm far from the patient's mouth, were incubated in 37°c for three days and the colonies were counted. Median, Interquartile eange and Wilcoxon test, at the 0.05 level of significance, were used to analyze the data."nResults: The median and interquartile range for the number of colony forming units (CFUS without aerosol- reduction device was 17.5 (8, 24, while the median for the number of CFUS when using aerosol-reduction device was 0 (0, 1, indicating significant statistical difference (PO.001 Conclusion: The aerosol- reduction device significantly reduces the amount of aerosols produced during ultrasonic scaling.

  15. Quantitative assessment of surf-produced sea spray aerosol

    NARCIS (Netherlands)

    Neele, F.P.; De Leeuw, G.; Jansen, M.; Stive, M.J.F.

    1998-01-01

    The first results are presented from a quantitative model describing the aerosol production in the surf zone. A comparison is made with aerosol produced in the surf zone as measured during EOPACE experiments in La Jolla and Monterey. The surf aerosol production was derived from aerosol concentration

  16. Applications of aerosol model in the reactor containment

    Directory of Open Access Journals (Sweden)

    Mossad Slama

    2014-10-01

    For spatially homogeneous aerosol of uniform chemical composition, the aerosol dynamic equation is solved in closed volume to simulate the radionuclide particle transport in the containment. The effects of initial conditions on the aerosol distribution, boundary layer thickness and the aerosol behaviour under source reinforcement (external source are considered.

  17. Gas/Aerosol partitioning: a simplified method for global modeling

    NARCIS (Netherlands)

    Metzger, S.M.

    2001-01-01

    The main focus of this thesis is the development of a simplified method to routinely calculate gas/aerosol partitioning of multicomponent aerosols and aerosol associated water within global atmospheric chemistry and climate models. Atmospheric aerosols are usually multicomponent mixtures, partl

  18. Secondary organic aerosol formation from primary aliphatic amines with NO3 radical

    Directory of Open Access Journals (Sweden)

    M. E. Erupe

    2008-07-01

    Full Text Available Primary aliphatic amines are an important class of nitrogen containing compounds found to be emitted from automobiles, waste treatment facilities and agricultural animal operations. A series of experiments conducted at the UC-Riverside/CE-CERT Environmental Chamber is presented in which oxidation of methylamine, ethylamine, propylamine, and butylamine with NO3 has been investigated. Very little aerosol formation is observed in the presence of O3 only. However, after addition of NO, and by extension NO3, large yields of aerosol mass loadings (~44% for butylamine are seen. Aerosol generated was determined to be organic in nature due to the small fraction of NO and NO2 in the total signal (<17% for all amines tested as detected by an aerosol mass spectrometer (AMS. We propose a reaction mechanism between carbonyl containing species and the parent amine leading to formation of particulate imine products. These findings can have significant impacts on rural communities and lead to elevated nighttime PM loadings, when significant levels on NO3 exist.

  19. Spent fuel sabotage test program, characterization of aerosol dispersal : technical review and analysis supplement.

    Energy Technology Data Exchange (ETDEWEB)

    Durbin, Samuel G.; Lindgren, Eric Richard

    2009-07-01

    This project seeks to provide vital data required to assess the consequences of a terrorist attack on a spent fuel transportation cask. One such attack scenario involves the use of conical shaped charges (CSC), which are capable of damaging a spent fuel transportation cask. In the event of such an attack, the amount of radioactivity that may be released as respirable aerosols is not known with great certainty. Research to date has focused on measuring the aerosol release from single short surrogate fuel rodlets subjected to attack by a small CSC device in various aerosol chamber designs. The last series of three experiments tested surrogate fuel rodlets made with depleted uranium oxide ceramic pellets in a specially designed double chamber aerosol containment apparatus. This robust testing apparatus was designed to prevent any radioactive release and allow high level radioactive waste disposal of the entire apparatus following testing of actual spent fuel rodlets as proposed. DOE and Sandia reviews of the project to date identified a number of issues. The purpose of this supplemental report is to address and document the DOE review comments and to resolve the issues identified in the Sandia technical review.

  20. Secondary organic aerosol formation from primary aliphatic amines with NO3 radical

    Directory of Open Access Journals (Sweden)

    P. J. Silva

    2009-03-01

    Full Text Available Primary aliphatic amines are an important class of nitrogen containing compounds emitted from automobiles, waste treatment facilities and agricultural animal operations. A series of experiments conducted at the UC-Riverside/CE-CERT Environmental Chamber is presented in which oxidation of methylamine, ethylamine, propylamine, and butylamine with O3 and NO3 have been investigated. Very little aerosol formation is observed in the presence of O3 only. However, after addition of NO, and by extension NO3, large aerosol mass yields (~44% for butylamine are seen. Aerosol generated was determined to be organic in nature due to the small fraction of NO and NO2 in the total signal (<1% for all amines tested as detected by an aerosol mass spectrometer (AMS. We propose a reaction mechanism between carbonyl containing species and the parent amine leading to formation of particulate imine products. These findings can have significant impacts on rural communities with elevated nighttime PM loadings, when significant levels of NO3 exist.

  1. How thermodynamic environments control stratocumulus microphysics and interactions with aerosols

    International Nuclear Information System (INIS)

    Aerosol–cloud interactions are central to climate system changes and depend on meteorological conditions. This study identifies distinct thermodynamic regimes and proposes a conceptual framework for interpreting aerosol effects. In the analysis, ten years (2003–2012) of daily satellite-derived aerosol and cloud products are combined with reanalysis data to identify factors controlling Southeast Atlantic stratocumulus microphysics. Considering the seasonal influence of aerosol input from biomass burning, thermodynamic environments that feature contrasting microphysical cloud properties and aerosol–cloud relations are classified. While aerosol impact is stronger in unstable environments, it is mostly confined to situations with low aerosol loading (aerosol index AI ≲ 0.15), implying a saturation of aerosol effects. Situations with high aerosol loading are associated with weaker, seasonally contrasting aerosol-droplet size relationships, likely caused by thermodynamically induced processes and aerosol swelling. (letter)

  2. Aerosol Chemistry of Furfural and Sugars

    Science.gov (United States)

    Srithawirat, T.; Brimblecombe, P.

    2008-12-01

    Furfural and sugars (as levoglucosan equivalent) are derived from biomass burning and contribute to aerosol composition. This study examined the potential of furfural and levoglucosan to be tracers of biomass burning. Furfural is likely to be oxidized quickly so comparison with levoglucosan may give a sense of the age of the aerosols in forest fire smoke. However, few furfural emissions are available for biomass combustion. Furfural and sugars were determined in coarse aerosols (>2.4μm aerodynamic diameter) and fine aerosols (Furfural and sugars dominated in fine fractions, especially in the UK autumn. Sugars were found at 5.96-18.37 nmol m-3 in fine mode and 1.36-5.75 nmol m-3 in coarse mode aerosols in the UK. Furfural was found at 0.18-0.91 nmol m-3 and 0.05-0.51 nmol m-3 respectively in the same aerosols. Sugars were a dominant contributor to aerosol derived from biomass burning. Sugars and furfural were about 10 and 20 times higher during haze episodes in Malaysia. Laboratory experimental simulation suggested furfural is more rapid destroyed by UV and sunlight than levoglucosan.

  3. Aerosol Angstrom Absorption Coefficient Comparisons during MILAGRO.

    Science.gov (United States)

    Marley, N. A.; Marchany-Rivera, A.; Kelley, K. L.; Mangu, A.; Gaffney, J. S.

    2007-12-01

    Measurements of aerosol absorption were obtained as part of the MAX-Mex component of the MILAGRO field campaign at site T0 (Instituto Mexicano de Petroleo in Mexico City) by using a 7-channel aethalometer (Thermo- Anderson) during the month of March, 2006. The absorption measurements obtained in the field at 370, 470, 520, 590, 660, 880, and 950 nm were used to determine the aerosol Angstrom absorption exponents by linear regression. Since, unlike other absorbing aerosol species (e.g. humic like substances, nitrated PAHs), black carbon absorption is relatively constant from the ultraviolet to the infrared with an Angstrom absorption exponent of -1 (1), a comparison of the Angstrom exponents can indicate the presence of aerosol components with an enhanced UV absorption over that expected from BC content alone. The Angstrom exponents determined from the aerosol absorption measurements obtained in the field varied from - 0.7 to - 1.3 during the study and was generally lower in the afternoon than the morning hours, indicating an increase in secondary aerosol formation and photochemically generated UV absorbing species in the afternoon. Twelve-hour integrated samples of fine atmospheric aerosols (Petroleo (IMP) and CENICA.

  4. Aerosol Angstrom Absorption Coefficient Comparisons during MILAGRO.

    Science.gov (United States)

    Marley, N. A.; Marchany-Rivera, A.; Kelley, K. L.; Mangu, A.; Gaffney, J. S.

    2007-12-01

    Measurements of aerosol absorption were obtained as part of the MAX-Mex component of the MILAGRO field campaign at site T0 (Instituto Mexicano de Petroleo in Mexico City) by using a 7-channel aethalometer (Thermo- Anderson) during the month of March, 2006. The absorption measurements obtained in the field at 370, 470, 520, 590, 660, 880, and 950 nm were used to determine the aerosol Angstrom absorption exponents by linear regression. Since, unlike other absorbing aerosol species (e.g. humic like substances, nitrated PAHs), black carbon absorption is relatively constant from the ultraviolet to the infrared with an Angstrom absorption exponent of -1 (1), a comparison of the Angstrom exponents can indicate the presence of aerosol components with an enhanced UV absorption over that expected from BC content alone. The Angstrom exponents determined from the aerosol absorption measurements obtained in the field varied from - 0.7 to - 1.3 during the study and was generally lower in the afternoon than the morning hours, indicating an increase in secondary aerosol formation and photochemically generated UV absorbing species in the afternoon. Twelve-hour integrated samples of fine atmospheric aerosols (MILAGRO. This research was supported by the Office of Science (BER), U.S. Department of Energy Grant No. DE-FG02-07ER64329. We also wish to thank Mexican Scientists and students for their assistance from the Instituto Mexicano de Petroleo (IMP) and CENICA.

  5. Phase transformation and growth of hygroscopic aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Tang, I.N.

    1995-09-01

    Ambient aerosols frequently contain large portions of hygroscopic inorganic salts such as chlorides, nitrates, and sulfates in either pure or mixed forms. Such inorganic salt aerosols exhibit the properties of deliquescence and efflorescence in air. The phase transformation from a solid particle to a saline droplet usually occurs spontaneously when the relative humidity of the atmosphere reaches a level specific to the chemical composition of the aerosol particle. Conversely, when the relative humidity decreases and becomes low enough, the saline droplet will evaporate and suddenly crystallize, expelling all its water content. The phase transformation and growth of aerosols play an important role in many atmospheric processes affecting air quality, visibility degradation, and climate changes. In this chapter, an exposition of the underlying thermodynamic principles is given, and recent advances in experimental methods utilizing single-particle levitation are discussed. In addition, pertinent and available thermodynamic data, which are needed for predicting the deliquescence properties of single and multi-component aerosols, are compiled. This chapter is useful to research scientists who are either interested in pursuing further studies of aerosol thermodynamics, or required to model the dynamic behavior of hygroscopic aerosols in a humid environment.

  6. Geochemical and Isotopic Composition of Aerosols in Tucson

    Science.gov (United States)

    Riha, K. M.; Michalski, G. M.; Lohse, K. A.; Gallo, E. L.; Brooks, P. D.; Meixner, T.

    2010-12-01

    Atmospheric nitrogen input to soils and surfaces in arid environments is of growing concern due to increased urbanization. Atmospheric nitrogen can be deposited as wet (rain or snow) or dry (dust or aerosols) deposition, and can lead to water eutrophication, soil acidification, and groundwater contamination through leaching of excess nitrate. Urbanization increases imperviousness which increases the magnitude of runoff and subsequently enhances groundwater recharge in arid and semi-arid regions. Following a rain pulse, nitrate deposited on impervious surfaces during dry periods is mobilized into ephemeral channels, where it can potentially infiltrate and reach groundwater. Anthropogenic nitrate sources include fertilizer from agriculture practices or lawn application, septic systems, and animal waste disposal. One way to determine the sources of nitrogen input to these environments is through the use of multiple isotope analysis (δ15N, δ18O and Δ17O ). The δ15N of nitrate can be used to distinguish between sources and when used in conjunction with δ18O better separation can be obtained due to distinct signatures (i.e. fertilizer is unique from septic). It has been shown that atmospheric nitrate is anomalously enriched in 17O (denoted Δ17O) (Michalski et al., 2003), while nitrate produced from nitrification, denitrification and assimilation have a Δ17O = 0. Using the Δ17O measurement can therefore allow us to determine the proportion of atmospheric nitrate in a sample. The objective of this research is to characterize the δ15N and δ18O values of atmospheric nitrate in Tucson. During 2006, daily PM10 and PM2.5 aerosol filters were collected from The Pima County Department of Environmental Quality. Aerosols show a seasonal mass trend with increased mass in the winter relative to spring, summer and fall. Anion concentrations (Cl-, NO3-, and SO42-) analyzed by ion chromatography, show similar seasonal variation that was present in the aerosol mass. Multiple

  7. Improvement of aerosol counterflow two-jets unit for continuous measurement of water soluble components of atmospheric aerosols

    Czech Academy of Sciences Publication Activity Database

    Mikuška, Pavel; Kořínková, Alena; Večeřa, Zbyněk

    Italian Aerosol Society, 2015. 2ACH_P033. [European Aerosol Conference EAC 2015. 06.09.2015-11.09.2015, Milano] R&D Projects: GA ČR(CZ) GA14-25558S Institutional support: RVO:68081715 Keywords : aerosol instrumentation * aerosol particles * chemical composition Subject RIV: CB - Analytical Chemistry, Separation

  8. Light Absorbing Aerosols in Mexico City

    Science.gov (United States)

    Marley, N. A.; Kelley, K. L.; Kilaparty, P. S.; Gaffney, J. S.

    2008-12-01

    The direct effects of aerosol radiative forcing has been identified by the IPCC as a major uncertainty in climate modeling. The DOE Megacity Aerosol Experiment-Mexico City (MAX-Mex), as part of the MILAGRO study in March of 2006, was undertaken to reduce these uncertainties by characterization of the optical, chemical, and physical properties of atmospheric aerosols emitted from this megacity environment. Aerosol samples collected during this study using quartz filters were characterized in the uv-visible-infrared by using surface spectroscopic techniques. These included the use of an integrating sphere approach combined with the use of Kubelka-Munk theory to obtain aerosol absorption spectra. In past work black carbon has been assumed to be the only major absorbing species in atmospheric aerosols with an broad band spectral profile that follows a simple inverse wavelength dependence. Recent work has also identified a number of other absorbing species that can also add to the overall aerosol absorption. These include primary organics from biomass and trash burning and secondary organic aerosols including nitrated PAHs and humic-like substances, or HULIS. By using surface diffuse reflection spectroscopy we have also obtained spectra in the infrared that indicate significant IR absorption in the atmospheric window-region. These data will be presented and compared to spectra of model compounds that allow for evaluation of the potential importance of these species in adding strength to the direct radiative forcing of atmospheric aerosols. This work was supported by the Office of Science (BER), U.S. Department of Energy, Grant No. DE-FG02-07ER64327 as part of the Atmospheric Science Program.

  9. Effects of seed aerosols on the growth of secondary organic aerosols from the photooxidation of toluene

    Institute of Scientific and Technical Information of China (English)

    HAO Li-qing; WANG Zhen-ya; HUANG Ming-qiang; FANG Li; ZHANG Wei-jun

    2007-01-01

    Hydroxyl radical (·OH)-initiated photooxidation reaction of toluene was carried out in a self-made smog chamber. Four individual seed aerosols such as ammonium sulfate, ammonium nitrate, sodium silicate and calcium chloride, were introduced into the chamber to assess their influence on the growth of secondary organic aerosols (SOA). It was found that the low concentration of seed aerosols might lead to high concentration of SOA particles. Seed aerosols would promote rates of SOA formation at the start of the reaction and inhibit its formation rate with prolonging the reaction time. In the case of cv. 9000 pt/cm3 seed aerosol load, the addition of sodium silicate induced a same effect on the SOA formation as ammonium nitrate. The influence of the four individual seed aerosols on the generation of SOA increased in the order of calcium chloride>sodium silicate and ammonium nitrate> ammonium sulfate.

  10. Papers of the 14. french congress on aerosols CFA 98

    International Nuclear Information System (INIS)

    This french congress on the aerosols took place in Paris the 8 and 9 december 1998. It was presented in four main themes: the aerosols in the environment; the bio-aerosols, filtering and purifying; the aerosols metrology; the aerosols physic and application. Seven papers have been analyzed in INIS data base for their specific interest in nuclear industry. Eight other ones are analyzed in ETDE data base. (A.L.B.)

  11. Applications of aerosol model in the reactor containment

    OpenAIRE

    Mossad Slama; Mohammad Omar Shaker; Ragaa Aly; Magdy Sirwah

    2014-01-01

    The study simulates of aerosol dynamics including coagulation, deposition and source reinforcement. Typical applications are for nuclear reactor aerosols, aerosol reaction chambers and the production of purified materials. The model determines the aerosol number and volume distributions for an arbitrary number of particle-size classes, called sections. The user specifies the initial aerosol size distribution and the source generation rate of each component in each section. For spatially ho...

  12. Secondary organic aerosols: Formation potential and ambient data

    DEFF Research Database (Denmark)

    Barthelmie, R.J.; Pryor, S.C.

    1997-01-01

    Organic aerosols comprise a significant fraction of the total atmospheric particle loading and are associated with radiative forcing and health impacts. Ambient organic aerosol concentrations contain both a primary and secondary component. Herein, fractional aerosol coefficients (FAC) are used in...... conjunction with measurements of volatile organic compounds (VOC) to predict the formation potential of secondary organic aerosols (SOA) in the Lower Fraser Valley (LEV) of British Columbia. The predicted concentrations of SOA show reasonable accord with ambient aerosol measurements and indicate considerable...

  13. Aerosol classification by airborne high spectral resolution lidar observations

    OpenAIRE

    S. Groß; Esselborn, M.; Weinzierl, B.; M. Wirth; Fix, A.; Petzold, A

    2012-01-01

    During four aircraft field experiments with the DLR research aircraft Falcon in 1998 (LACE), 2006 (SAMUM-1) and 2008 (SAMUM-2 and EUCAARI), airborne High Spectral Resolution Lidar (HSRL) and in situ measurements of aerosol microphysical and optical properties were performed. Altogether, the properties of six different aerosol types and aerosol mixtures – Saharan mineral dust, Saharan dust mixtures, Canadian biomass burning aerosol, African biomass burning aerosol, anthropogenic polluti...

  14. Whole-body nanoparticle aerosol inhalation exposures.

    Science.gov (United States)

    Yi, Jinghai; Chen, Bean T; Schwegler-Berry, Diane; Frazer, Dave; Castranova, Vince; McBride, Carroll; Knuckles, Travis L; Stapleton, Phoebe A; Minarchick, Valerie C; Nurkiewicz, Timothy R

    2013-01-01

    Inhalation is the most likely exposure route for individuals working with aerosolizable engineered nano-materials (ENM). To properly perform nanoparticle inhalation toxicology studies, the aerosols in a chamber housing the experimental animals must have: 1) a steady concentration maintained at a desired level for the entire exposure period; 2) a homogenous composition free of contaminants; and 3) a stable size distribution with a geometric mean diameter generation of aerosols containing nanoparticles is quite challenging because nanoparticles easily agglomerate. This is largely due to very strong inter-particle forces and the formation of large fractal structures in tens or hundreds of microns in size (6), which are difficult to be broken up. Several common aerosol generators, including nebulizers, fluidized beds, Venturi aspirators and the Wright dust feed, were tested; however, none were able to produce nanoparticle aerosols which satisfy all criteria (5). A whole-body nanoparticle aerosol inhalation exposure system was fabricated, validated and utilized for nano-TiO2 inhalation toxicology studies. Critical components: 1) novel nano-TiO2 aerosol generator; 2) 0.5 m(3) whole-body inhalation exposure chamber; and 3) monitor and control system. Nano-TiO2 aerosols generated from bulk dry nano-TiO2 powders (primary diameter of 21 nm, bulk density of 3.8 g/cm(3)) were delivered into the exposure chamber at a flow rate of 90 LPM (10.8 air changes/hr). Particle size distribution and mass concentration profiles were measured continuously with a scanning mobility particle sizer (SMPS), and an electric low pressure impactor (ELPI). The aerosol mass concentration (C) was verified gravimetrically (mg/m(3)). The mass (M) of the collected particles was determined as M = (Mpost-Mpre), where Mpre and Mpost are masses of the filter before and after sampling (mg). The mass concentration was calculated as C = M/(Q*t), where Q is sampling flowrate (m(3)/min), and t is the sampling

  15. Capstone Depleted Uranium Aerosols: Generation and Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Parkhurst, MaryAnn; Szrom, Fran; Guilmette, Ray; Holmes, Tom; Cheng, Yung-Sung; Kenoyer, Judson L.; Collins, John W.; Sanderson, T. Ellory; Fliszar, Richard W.; Gold, Kenneth; Beckman, John C.; Long, Julie

    2004-10-19

    In a study designed to provide an improved scientific basis for assessing possible health effects from inhaling depleted uranium (DU) aerosols, a series of DU penetrators was fired at an Abrams tank and a Bradley fighting vehicle. A robust sampling system was designed to collect aerosols in this difficult environment and continuously monitor the sampler flow rates. Aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. They were also analyzed for uranium oxide phases, particle morphology, and dissolution in vitro. The resulting data provide input useful in human health risk assessments.

  16. Aerosol transport in severe reactor accidents

    International Nuclear Information System (INIS)

    Computer codes with different aerosol models were used for calculation of fission product transport and the results are compared. Experimental results from LACE, DEMONA and Marviken-V are compared with the calculations. The theory of aerosol nucleation and its influence on the fission product transport is discussed. The behaviour of hygroscopic aerosols is studied. The pool scrubbing models in the codes SPARC and SUPRA are reviewed and some calculational results are reported. The present status of knowledge in this field is assessed on the background of an international review. (orig./HP)

  17. The behaviour of sodium fire aerosols

    International Nuclear Information System (INIS)

    The knowledge of the behaviour of aerosols released in nuclear accidents is of great importance for nuclear reactor safety and environmental protection. In sodium cooled fast breeder reactor accidents may occur by leaking pipes resulting in considerable spill of sodium. Major amounts of airborne sodium fire aerosols will be formed due to the evaporation and reaction of hot sodium with oxygen. For estimating the environmental impact of these aerosols it is necessary to know their chemical and physical behaviour in containments and in the free atmosphere

  18. Electrical aerosol spectrometer of Tartu University

    Science.gov (United States)

    Tammet, H.; Mirme, A.; Tamm, E.

    The electrical aerosol spectrometer (EAS) of the parallel measuring principle at Tartu University is an efficient instrument for rapid measurement of the unstable size spectrum of aerosol particles. The measuring range from 10 nm to 10 μm is achieved by simultaneously using a pair of differential mobility analyzers with two different particle chargers. The particle spectrum is calculated and measurement errors are estimated in real time by using a least-squares method. Experimental calibration ensures reliability of measurement. The instrument is well suited for continuous monitoring of atmospheric aerosol.

  19. Aerosol versus solution composition in occupational exposures.

    Science.gov (United States)

    Rondia, D; Closset, J

    1985-11-01

    Some industrial processes, such as the electrolysis of zinc solutions, anodic oxidation of aluminum, ore flotation, etc., result in the generation of gas microbubbles; the composition of their liquid envelope depends on, but is not identical to, the composition of the bulk of the liquid phase. An aerosol of respirable size, often toxic or irritant, results from the bursting of the bubbles at a certain height above the liquid. Some factors governing the discrepancy between the composition of the aerosol and that of the liquid have been studied for metal ions in oceanic aerosols. It is not known if these factors also apply to concentrated solutions and to anions. PMID:4081778

  20. Direct SW aerosol radiative forcing over Portugal

    Directory of Open Access Journals (Sweden)

    D. Santos

    2008-10-01

    Full Text Available In this work, the evaluation of the aerosol radiative forcing at the top of the atmosphere as well as at the surface over the south of Portugal is made, particularly in the regions of Évora (38°34' N, 7°54' W and of Cabo da Roca (38°46' N, 9°38' W, during years 2004 and 2005.

    The radiative transfer calculations, using the radiative transfer code Second Simulation of the Satellite Signal in the Solar Spectrum (6S, combine ground-based measurements, from Aerosol Robotic NETwork (AERONET, and satellite measurements, from MODerate Imaging Spectroradiometer (MODIS, to estimate the direct SW aerosol radiative forcing. The method developed to retrieve the surface spectral reflectance is also presented, based on ground-based measurements (AERONET of the aerosol optical properties combined with the satellite-measured radiances (MODIS.

    The instantaneous direct SW aerosol radiative forcing values obtained at the top of the atmosphere are, in the majority of the cases, negative, indicating a tendency for cooling the Earth at the top of the atmosphere. For Desert Dust aerosols, over the Évora land region, the average forcing efficiency is estimated to be −25 Wm−2/AOT0.55 whereas for the Cabo da Roca area, the average forcing efficiency is −46 Wm−2/AOT0.55. In the presence of Forest Fire aerosols, both from short and long distances, the average value of forcing efficiency at the top of the atmosphere over Cabo da Roca is found to be −28 Wm−2/AOT0.55 and, over Évora, −27 Wm−2/AOT0.55. For specific situations, discussed in this work, the average surface direct SW aerosol radiative forcing efficiency due to the Desert Dust aerosols, in Évora region, is −66 Wm−2/AOT0.55, whereas in Cabo da Roca region, the corresponding average value is −38 Wm−2/AOT0.55

  1. Direct SW aerosol radiative forcing over Portugal

    Directory of Open Access Journals (Sweden)

    D. Santos

    2008-05-01

    Full Text Available The estimation of radiative forcing due to desert dust and forest fires aerosols is a very important issue since these particles are very efficient at scattering and absorbing both short and longwave radiation. In this work, the evaluation of the aerosol radiative forcing at the top of the atmosphere over the south of Portugal is made, particularly in the regions of Évora and of Cabo da Roca.

    The radiative transfer calculations combine ground-based and satellite measurements, to estimate the top of the atmosphere direct SW aerosol radiative forcing. The method developed to retrieve the surface spectral reflectance is also presented, based on ground-based measurements of the aerosol optical properties combined with the satellite-measured radiances.

    The aerosol direct radiative effect is shown to be very sensitive to the underlying surface, since different surface spectral reflectance values may originate different forcing values. The results obtained also illustrate the importance of considering the actual aerosol properties, in this case measured by ground-based instrumentation, particularly the aerosol single scattering albedo, because different aerosol single scattering albedo values can flip the sign of the direct SW aerosol radiative forcing.

    The instantaneous direct SW aerosol radiative forcing values obtained at the top of the atmosphere are, in the majority of the cases, negative, indicating a tendency for cooling the Earth. For Desert Dust aerosols, over Évora land region, the average forcing efficiency is estimated to be −25 W/m2/AOT0.55 whereas for Cabo da Roca area, the average forcing efficiency is −46 W/m2/AOT0.55. In the presence of Forest Fire aerosols, over Cabo da Roca region, the average value of forcing efficiency is −28 W/m2/AOT0.55 and over Évora region an average value of −33 W/m2/AOT0.55 is found.

  2. Nitrate aerosols today and in 2030: a global simulation including aerosols and tropospheric ozone

    OpenAIRE

    S. E. Bauer; Koch, D.; Unger, N.; Metzger, S. M.; Shindell, D. T.; Streets, D.G.

    2007-01-01

    Nitrate aerosols are expected to become more important in the future atmosphere due to the expected increase in nitrate precursor emissions and the decline of ammonium-sulphate aerosols in wide regions of this planet. The GISS climate model is used in this study, including atmospheric gas- and aerosol phase chemistry to investigate current and future (2030, following the SRES A1B emission scenario) atmospheric compositions. A set of sensitivity experiments was carried out to...

  3. Nitrate aerosols today and in 2030: a global simulation including aerosols and tropospheric ozone

    OpenAIRE

    S. E. Bauer; Koch, D.; Unger, N.; Metzger, S. M.; Shindell, D. T.; Streets, D.G.

    2007-01-01

    Nitrate aerosols are expected to become more important in the future atmosphere due to the expected increase in nitrate precursor emissions and the decline of ammonium-sulphate aerosols in wide regions of this planet. The GISS climate model is used in this study, including atmospheric gas- and aerosol phase chemistry to investigate current and future (2030, following the SRES A1B emission scenario) atmospheric compositions. A set of sensitivity experiments was carried out to quantify the indi...

  4. Importance of global aerosol modeling including secondary organic aerosol formed from monoterpene

    OpenAIRE

    Goto, Daisuke; Takemura, Toshihiko; Nakajima, Teruyuki

    2008-01-01

    A global three-dimensional aerosol transport-radiation model, coupled to an atmospheric general circulation model (AGCM), has been extended to improve the model process for organic aerosols, particularly secondary organic aerosols (SOA), and to estimate SOA contributions to direct and indirect radiative effects. Because the SOA formation process is complicated and unknown, the results in different model simulations include large differences. In this work, we simulate SOA production assuming v...

  5. Do anthropogenic, continental or coastal aerosol sources impact on a marine aerosol signature at Mace Head?

    OpenAIRE

    C. O'Dowd; Ceburnis, D.; J. Ovadnevaite; A Vaishya; Rinaldi, M.; Facchini, M. C.

    2014-01-01

    Atmospheric aerosols have been sampled and characterised at the Mace Head north-east (NE) Atlantic atmospheric research station since 1958, with many interesting phenomena being discovered. However, with the range of new discoveries and scientific advances, there has been a range of concomitant criticisms challenging the representativeness of aerosol sampled at the station compared to that of aerosol over the pristine open-ocean. Two recurring criticisms relate to the lack o...

  6. Nitrate aerosols today and in 2030: importance relative to other aerosol species and tropospheric ozone

    Directory of Open Access Journals (Sweden)

    S. E. Bauer

    2007-04-01

    Full Text Available Ammonium-nitrate aerosols are expected to become more important in the future atmosphere due to the expected increase in nitrate precursor emissions and the decline of ammonium-sulphate aerosols in wide regions of this planet. The GISS climate model is used in this study, including atmospheric gas- and aerosol phase chemistry to investigate current and future (2030, following the SRES A1B emission scenario atmospheric compositions. A set of sensitivity experiments was carried out to quantify the individual impact of emission- and physical climate change on nitrate aerosol formation. We found that future nitrate aerosol loads depend most strongly on changes that may occur in the ammonia sources. Furthermore, microphysical processes that lead to aerosol mixing play a very important role in sulphate and nitrate aerosol formation. The role of nitrate aerosols as climate change driver is analyzed and set in perspective to other aerosol and ozone forcings under pre-industrial, present day and future conditions. In the near future, year 2030, ammonium nitrate radiative forcing is about –0.14 W/m2 and contributes roughly 10% of the net aerosol and ozone forcing. The present day nitrate and pre-industrial nitrate forcings are –0.11 and –0.05 W/m2, respectively. The steady increase of nitrate aerosols since industrialization increases its role as a non greenhouse gas forcing agent. However, this impact is still small compared to greenhouse gas forcings, therefore the main role nitrate will play in the future atmosphere is as an air pollutant, with annual mean near surface air concentrations rising above 3 μg/m3 in China and therefore reaching pollution levels, like sulphate aerosols, in the fine particle mode.

  7. Nitrate aerosols today and in 2030: a global simulation including aerosols and tropospheric ozone

    Directory of Open Access Journals (Sweden)

    S. E. Bauer

    2007-10-01

    Full Text Available Nitrate aerosols are expected to become more important in the future atmosphere due to the expected increase in nitrate precursor emissions and the decline of ammonium-sulphate aerosols in wide regions of this planet. The GISS climate model is used in this study, including atmospheric gas- and aerosol phase chemistry to investigate current and future (2030, following the SRES A1B emission scenario atmospheric compositions. A set of sensitivity experiments was carried out to quantify the individual impact of emission- and physical climate change on nitrate aerosol formation. We found that future nitrate aerosol loads depend most strongly on changes that may occur in the ammonia sources. Furthermore, microphysical processes that lead to aerosol mixing play a very important role in sulphate and nitrate aerosol formation. The role of nitrate aerosols as climate change driver is analyzed and set in perspective to other aerosol and ozone forcings under pre-industrial, present day and future conditions. In the near future, year 2030, ammonium nitrate radiative forcing is about −0.14 W/m² and contributes roughly 10% of the net aerosol and ozone forcing. The present day nitrate and pre-industrial nitrate forcings are −0.11 and −0.05 W/m², respectively. The steady increase of nitrate aerosols since industrialization increases its role as a non greenhouse gas forcing agent. However, this impact is still small compared to greenhouse gas forcings, therefore the main role nitrate will play in the future atmosphere is as an air pollutant, with annual mean near surface air concentrations, in the fine particle mode, rising above 3 μg/m³ in China and therefore reaching pollution levels, like sulphate aerosols.

  8. Natural Radionuclides and Isotopic Signatures for Determining Carbonaceous Aerosol Sources, Aerosol Lifetimes, and Washout Processes

    Energy Technology Data Exchange (ETDEWEB)

    Gaffney, Jeffrey [Univ. of Arkansas, Little Rock, AR (United States)

    2012-12-12

    This is the final technical report. The project description is as follows: to determine the role of aerosol radiative forcing on climate, the processes that control their atmospheric concentrations must be understood, and aerosol sources need to be determined for mitigation. Measurements of naturally occurring radionuclides and stable isotopic signatures allow the sources, removal and transport processes, as well as atmospheric lifetimes of fine carbonaceous aerosols, to be evaluated.

  9. Simultaneous aerosol measurements of unusual aerosol enhancement in troposphere over Syowa Station, Antarctica

    Directory of Open Access Journals (Sweden)

    K. Hara

    2013-10-01

    Full Text Available Unusual aerosol enhancement is often observed at Syowa Station, Antarctica during winter through spring. Simultaneous aerosol measurements near the surface and in the upper atmosphere were conducted twice using a ground-based optical particle counter, a balloon-borne optical particle counter, and micro-pulse LIDAR (MPL in August and September 2012. During 13–15 August, aerosol enhancement occurred immediately after a storm condition. A high backscatter ratio and aerosol concentrations were observed from the surface to ca. 2.5 km over Syowa Station. Clouds appeared occasionally at the top of aerosol-enhanced layer during the episode. Aerosol enhancement was terminated on 15 August by strong winds caused by a cyclone's approach. In the second case on 5–7 September, aerosol number concentrations in Dp > 0.3 μm near the surface reached > 104 L−1 at about 15:00 UT on 5 September in spite of calm wind conditions, whereas MPL measurement exhibited aerosols were enhanced at about 04:00 UT at 1000–1500 m above Syowa Station. The aerosol enhancement occurred near the surface–ca. 4 km. In both cases, air masses with high aerosol enhancement below 2.5–3 km were transported mostly from the boundary layer over the sea-ice area. In addition, air masses at 3–4 km in the second case came from the boundary layer over the open-sea area. This air mass history strongly suggests that dispersion of sea-salt particles from the sea-ice surface contributes considerably to the aerosol enhancement in the lower free troposphere (about 3 km and that the release of sea-salt particles from the ocean surface engenders high aerosol concentrations in the free troposphere (3–4 km.

  10. Do anthropogenic or coastal aerosol sources impact on a clean marine aerosol signature at Mace Head?

    OpenAIRE

    C. O'Dowd; D. Ceburnis; J. Ovadnevaite; Rinaldi, M.; Facchini, M. C.

    2013-01-01

    Atmospheric aerosols have been sampled and characterised at the Mace Head North East (N.E.) Atlantic atmospheric research station since 1958, with many interesting phenomena being discovered. However, with the range of new discoveries and scientific advances, there has been a range of concomitant criticisms challenging the representativeness of aerosol sampled at the station to that of aerosol over the open ocean. Two recurring criticisms relate to the lack of representativeness due to enhanc...

  11. Search for Links between Organic Aerosols Measured by Aerosol Mass Spectrometer and EC/OC Analyzer

    Czech Academy of Sciences Publication Activity Database

    Vodička, Petr; Kubelová, Lucie; Makeš, Otakar; Schwarz, Jaroslav

    Prague : Czech Aerosol Society, 2014 - (Kubelová, L.), s. 47-48 ISBN 978-80-86186-64-1. [Annual Conference of the Czech Aerosol Society /15./. Valtice (CZ), 30.10.2014-31.10.2014] R&D Projects: GA ČR GAP209/11/1342 Institutional support: RVO:67985858 Keywords : atmospheric aerosols * AMS * ECOC Subject RIV: CF - Physical ; Theoretical Chemistry http://cas.icpf.cas.cz/download/Sbornik_VKCAS_2014.pdf

  12. Characterization of urban aerosol in Cork City (Ireland using aerosol mass spectrometry

    Directory of Open Access Journals (Sweden)

    M. Dall'Osto

    2012-11-01

    Full Text Available Ambient wintertime background urban aerosol in Cork City, Ireland, was characterized using aerosol mass spectrometry. During the three-week measurement study in 2009, 93% of the 1 200 000 single particles characterized by an Aerosol Time-Of-Flight Mass Spectrometer (TSI ATOFMS were classified into five organic-rich particle types, internally-mixed to different proportions with Elemental Carbon (EC, sulphate and nitrate while the remaining 7% was predominantly inorganic in nature. Non-refractory PM1 aerosol was also characterized using a High Resolution Time-Of-Flight Aerodyne Aerosol Mass Spectrometer (HR-ToF-AMS and was also found to comprise organic matter as the most abundant species (62%, followed by nitrate (15%, sulphate (9% and ammonium (9%, and then chloride (5%.

    Positive matrix factorization (PMF was applied to the HR-ToF-AMS organic matrix and a five-factor solution was found to describe the variance in the data well. Specifically, "Hydrocarbon-like" Organic Aerosol (HOA comprised 19% of the mass, "Oxygenated low volatility" Organic Aerosols (LV-OOA comprised 19%, "Biomass wood Burning" Organic Aerosol (BBOA comprised 23%, non-wood solid-fuel combustion "Peat and Coal" Organic Aerosol (PCOA comprised 21%, and finally, a species type characterized by primary m/z peaks at 41 and 55, similar to previously-reported "Cooking" Organic Aerosol (COA but possessing different diurnal variations to what would be expected for cooking activities, contributed 18%. Despite wood, cool and peat being minor fuel types used for domestic space heating in urban areas, their relatively low combustion efficiencies result in a significant contribution to PM1 aerosol mass (44% and 28% of the total organic aerosols mass and non refractory PM1, respectively.

  13. Simulation of climate response to aerosol direct and indirect effects with aerosol transport‐radiation model

    OpenAIRE

    Takemura, Toshihiko; Nozawa, Toru; Emori, Seita; Nakajima, Takashi-Y.; Nakajima, Teruyuki

    2005-01-01

    With a global aerosol transport‐radiation model coupled to a general circulation model, changes in the meteorological parameters of clouds, precipitation, and temperature caused by the direct and indirect effects of aerosols are simulated, and its radiative forcing are calculated. A microphysical parameterization diagnosing the cloud droplet number concentration based on the Köhler theory is introduced into the model, which depends not only on the aerosol particle number concentration but als...

  14. Natural Radionuclides and Isotopic Signatures for Determining Carbonaceous Aerosol Sources, Aerosol Lifetimes, and Washout Processes

    International Nuclear Information System (INIS)

    This is the final technical report. The project description is as follows: to determine the role of aerosol radiative forcing on climate, the processes that control their atmospheric concentrations must be understood, and aerosol sources need to be determined for mitigation. Measurements of naturally occurring radionuclides and stable isotopic signatures allow the sources, removal and transport processes, as well as atmospheric lifetimes of fine carbonaceous aerosols, to be evaluated.

  15. Wintertime measurements of aerosol acidity and trace elements in Wuhan, a city in central China

    Science.gov (United States)

    Waldman, J. M.; Lioy, P. J.; Zelenka, M.; Jing, L.; Lin, Y. N.; He, Q. C.; Qian, Z. M.; Chapman, R.; Wilson, W. E.

    abundance of carbonaceous aerosol, as high as 100 μ m -3 Aerosol acidity was negligible during most monitoring periods, H +: 14 (range 0-50 neq m -3, equivalent to 0-2.5 μm m -3 as H 2SO 4). Sulfur dioxide, measured by the West-Gaeke method for part of the study, concentrations were low. Although not directly measured, the aerosol measurments suggested that gaseous HCl (from refuse incineration) and NH 3 (animal wastes) concentrations might have been high. Higher aerosol acidity might be expected if HCl sources were more prominent and not neutralized by local ammonia or other base components.

  16. The Two-Column Aerosol Project: Phase I - Overview and Impact of Elevated Aerosol Layers on Aerosol Optical Depth

    Energy Technology Data Exchange (ETDEWEB)

    Berg, Larry K.; Fast, Jerome D.; Barnard, James C.; Burton, Sharon; Cairns, Brian; Chand, Duli; Comstock, Jennifer M.; Dunagan, Stephen; Ferrare, Richard A.; Flynn, Connor J.; Hair, John; Hostetler, Chris A.; Hubbe, John M.; Jefferson, Anne; Johnson, Roy; Kassianov, Evgueni I.; Kluzek, Celine D.; Kollias, Pavlos; Lamer, Katia; Lantz, K.; Mei, Fan; Miller, Mark A.; Michalsky, Joseph; Ortega, Ivan; Pekour, Mikhail S.; Rogers, Ray; Russell, P.; Redemann, Jens; Sedlacek, Art; Segal Rozenhaimer, Michal; Schmid, Beat; Shilling, John E.; Shinozuka, Yohei; Springston, Stephen R.; Tomlinson, Jason M.; Tyrrell, Megan; Wilson, Jacqueline; Volkamer, Rainer M.; Zelenyuk, Alla; Berkowitz, Carl M.

    2016-01-08

    The Two-Column Aerosol Project (TCAP), which was conducted from June 2012 through June 2013, was a unique field study that was designed to provide a comprehensive data set that can be used to investigate a number of important climate science questions, including those related to aerosol mixing state and aerosol radiative forcing. The study was designed to sample the atmosphere at a number of altitudes, from near the surface to as high as 8 km, within two atmospheric columns; one located near the coast of North America (over Cape Cod, MA) and a second over the Atlantic Ocean several hundred kilometers from the coast. TCAP included the yearlong deployment of the U.S. Department of Energy’s (DOE) Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) that was located at the base of the Cape Cod column, as well as summer and winter aircraft intensive observation periods of the ARM Aerial Facility. One important finding from TCAP is the relatively common occurrence (on four of six nearly cloud-free flights) of elevated aerosol layers in both the Cape Cod and maritime columns that were detected using the nadir pointing second-generation NASA high-spectral resolution lidar (HSRL-2). These layers contributed up to 60% of the total aerosol optical depth (AOD) observed in the column. Many of these layers were also intercepted by the aircraft configured for in situ sampling, and the aerosol in the layers was found to have increased amounts of biomass burning aerosol and nitrate compared to the aerosol found near the surface.

  17. The Truth about Stratospheric Aerosols: Key Results from SPARC`s Assessment of Stratospheric Aerosol Properties

    Science.gov (United States)

    Thomason, L. W.; Peter, T.

    2005-12-01

    Given the critical role it plays in ozone chemistry, the Assessment of Stratospheric Aerosol Properties (ASAP) has been carried out by the WCRP project on Stratospheric Process and their Role in Climate (SPARC). The objective of this report was to present a systematic analysis of the state of knowledge of stratospheric aerosols including their precursors. It includes an examination of precursor concentrations and trends, measurements of stratospheric aerosol properties, trends in those properties, and modeling their formation, transport, and distribution in both background and volcanic conditions. The assessment found that the dominant nonvolcanic stratospheric aerosol precursor gases are OCS, SO2, and tropospheric aerosol. Therefore, though SO2, human-related activities play a significant role in the observed background stratospheric aerosol. There is general agreement between measured OCS and modeling of its transformation to sulfate aerosol, and observed aerosols. However, there is a significant dearth of SO2 measurements, and the role of tropospheric SO2 in the stratospheric aerosol budget - while significant - remains a matter of some guesswork. The assessment also found that there is basic agreement between the various data sets and models particularly during periods of elevated loading. However, at background levels significant differences were found that indicate that substantial questions remain regarding the nature of stratospheric aerosol during these periods particularly in the lower stratosphere. For instance, during periods of very low aerosol loading significant differences exist between systems for key parameters including aerosol surface area density and extinction. At the same time, comparisons of models and satellite observations of aerosol extinction found good agreement at visible wavelengths above 20-25 km altitude region but are less satisfactory for infrared wavelengths. While there are some model short-comings relative to observations in

  18. Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

    Energy Technology Data Exchange (ETDEWEB)

    Richard A. Ferrare; David D. Turner

    2011-09-01

    Project goals: (1) Use the routine surface and airborne measurements at the ARM SGP site, and the routine surface measurements at the NSA site, to continue our evaluations of model aerosol simulations; (2) Determine the degree to which the Raman lidar measurements of water vapor and aerosol scattering and extinction can be used to remotely characterize the aerosol humidification factor; (3) Use the high temporal resolution CARL data to examine how aerosol properties vary near clouds; and (4) Use the high temporal resolution CARL and Atmospheric Emitted Radiance Interferometer (AERI) data to quantify entrainment in optically thin continental cumulus clouds.

  19. Ensembles of satellite aerosol retrievals based on three AATSR algorithms within aerosol_cci

    Science.gov (United States)

    Kosmale, Miriam; Popp, Thomas

    2016-04-01

    Ensemble techniques are widely used in the modelling community, combining different modelling results in order to reduce uncertainties. This approach could be also adapted to satellite measurements. Aerosol_cci is an ESA funded project, where most of the European aerosol retrieval groups work together. The different algorithms are homogenized as far as it makes sense, but remain essentially different. Datasets are compared with ground based measurements and between each other. Three AATSR algorithms (Swansea university aerosol retrieval, ADV aerosol retrieval by FMI and Oxford aerosol retrieval ORAC) provide within this project 17 year global aerosol records. Each of these algorithms provides also uncertainty information on pixel level. Within the presented work, an ensembles of the three AATSR algorithms is performed. The advantage over each single algorithm is the higher spatial coverage due to more measurement pixels per gridbox. A validation to ground based AERONET measurements shows still a good correlation of the ensemble, compared to the single algorithms. Annual mean maps show the global aerosol distribution, based on a combination of the three aerosol algorithms. In addition, pixel level uncertainties of each algorithm are used for weighting the contributions, in order to reduce the uncertainty of the ensemble. Results of different versions of the ensembles for aerosol optical depth will be presented and discussed. The results are validated against ground based AERONET measurements. A higher spatial coverage on daily basis allows better results in annual mean maps. The benefit of using pixel level uncertainties is analysed.

  20. Overview of ACE-Asia Spring 2001 Investigations on Aerosol Radiative Effects and Related Aerosol Properties

    Science.gov (United States)

    Russell, Philip B.; Valero, F. P. J.; Flatau, P. J.; Bergin, M.; Holben, B.; Nakajima, T.; Pilewskie, P.; Bergstrom, R.; Hipskind, R. Stephen (Technical Monitor)

    2001-01-01

    A primary, ACE-Asia objective was to quantify the interactions between aerosols and radiation in the Asia-Pacific region. Toward this end, radiometric and related aerosol measurements were made from ocean, land, air and space platforms. Models that predict aerosol fields guided the measurements and are helping integrate and interpret results. Companion overview's survey these measurement and modeling components. Here we illustrate how these components were combined to determine aerosol radiative. impacts and their relation to aerosol properties. Because clouds can obscure or change aerosol direct radiative effects, aircraft and ship sorties to measure these effects depended on predicting and finding cloud-free areas and times with interesting aerosols present. Pre-experiment satellite cloud climatologies, pre-flight aerosol and cloud forecasts, and in-flight guidance from satellite imagery all helped achieve this. Assessments of aerosol regional radiative impacts benefit from the spatiotemporal coverage of satellites, provided satellite-retrieved aerosol properties are accurate. Therefore, ACE-Asia included satellite retrieval tests, as part of many comparisons to judge the consistency (closure) among, diverse measurements. Early results include: (1) Solar spectrally resolved and broadband irradiances and optical depth measurements from the C-130 aircraft and at Kosan, Korea yielded aerosol radiative forcing efficiencies, permitting comparisons between efficiencies of ACE-Asia and INDOEX aerosols, and between dust and "pollution" aerosols. Detailed results will be presented in separate papers. (2) Based on measurements of wavelength dependent aerosol optical depth (AOD) and single scattering albedo the estimated 24-h a average aerosol radiative forcing efficiency at the surface for photosynthetically active radiation (400 - 700 nm) in Yulin, China is approx. 30 W sq m per AOD(500 nm). (3) The R/V Brown cruise from Honolulu to Sea of Japan sampled an aerosol optical

  1. Small-Scale Spray Releases: Initial Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

    2013-05-29

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and net generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of antifoam agents was assessed with most of the simulants. Orifices included round holes and

  2. Small-Scale Spray Releases: Initial Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

    2012-11-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and

  3. Large-Scale Spray Releases: Initial Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Schonewill, Philip P.; Gauglitz, Phillip A.; Bontha, Jagannadha R.; Daniel, Richard C.; Kurath, Dean E.; Adkins, Harold E.; Billing, Justin M.; Burns, Carolyn A.; Davis, James M.; Enderlin, Carl W.; Fischer, Christopher M.; Jenks, Jeromy WJ; Lukins, Craig D.; MacFarlan, Paul J.; Shutthanandan, Janani I.; Smith, Dennese M.

    2012-12-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and

  4. Papers of the 14. french congress on aerosols CFA 98; Actes du 14. congres francais sur les aerosols CFA 98

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This french congress on the aerosols took place in Paris the 8 and 9 december 1998. It was presented in four main themes: the aerosols in the environment; the bio-aerosols, filtering and purifying; the aerosols metrology; the aerosols physic and application. Seven papers have been analyzed in INIS data base for their specific interest in nuclear industry. Eight other ones are analyzed in ETDE data base. (A.L.B.)

  5. Evaluation of spatio-temporal variability of Hamburg Aerosol Climatology against aerosol datasets from MODIS and CALIOP

    OpenAIRE

    V. Pappas; N. Hatzianastassiou; C. Papadimas; Matsoukas, C.; Kinne, S.; Vardavas, I.

    2013-01-01

    The new global aerosol climatology named HAC (Hamburg Aerosol Climatology) is compared against MODIS (MODerate resolution Imaging Spectroradiometer, Collection 5, 2000–2007) and CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization, Level 2-Version 3, 2006–2011) retrievals. The HAC aerosol optical depth (AOD) values are larger than MODIS in heavy aerosol load conditions (over land) and lower over oceans. Agreement between HAC and MODIS is better over land and for low AOD. Hemispherica...

  6. Retrieving global aerosol sources from satellites using inverse modeling

    Directory of Open Access Journals (Sweden)

    O. Dubovik

    2008-01-01

    Full Text Available Understanding aerosol effects on global climate requires knowing the global distribution of tropospheric aerosols. By accounting for aerosol sources, transports, and removal processes, chemical transport models simulate the global aerosol distribution using archived meteorological fields. We develop an algorithm for retrieving global aerosol sources from satellite observations of aerosol distribution by inverting the GOCART aerosol transport model.

    The inversion is based on a generalized, multi-term least-squares-type fitting, allowing flexible selection and refinement of a priori algorithm constraints. For example, limitations can be placed on retrieved quantity partial derivatives, to constrain global aerosol emission space and time variability in the results. Similarities and differences between commonly used inverse modeling and remote sensing techniques are analyzed. To retain the high space and time resolution of long-period, global observational records, the algorithm is expressed using adjoint operators.

    Successful global aerosol emission retrievals at 2°×2.5 resolution were obtained by inverting GOCART aerosol transport model output, assuming constant emissions over the diurnal cycle, and neglecting aerosol compositional differences. In addition, fine and coarse mode aerosol emission sources were inverted separately from MODIS fine and coarse mode aerosol optical thickness data, respectively. These assumptions are justified, based on observational coverage and accuracy limitations, producing valuable aerosol source locations and emission strengths. From two weeks of daily MODIS observations during August 2000, the global placement of fine mode aerosol sources agreed with available independent knowledge, even though the inverse method did not use any a priori information about aerosol sources, and was initialized with a "zero aerosol emission" assumption. Retrieving coarse mode aerosol emissions was less successful

  7. Waste disposal

    CERN Multimedia

    2006-01-01

    We should like to remind you that you can have all commonplace, conventional waste (combustible, inert, wood, etc.) disposed of by the TS-FM Group. Requests for the removal of such waste should be made by contacting FM Support on tel. 77777 or by e-mail (Fm.Support@cern.ch). For requests to be acted upon, the following information must be communicated to FM Support: budget code to be debited for the provision and removal of the skip / container; type of skip required (1m3, 4 m3, 7 m3, 15 m3, 20 m3, 30 m3); nature of the waste to be disposed of (bulky objects, cardboard boxes, etc.); building concerned; details of requestor (name, phone number, department, group, etc.). We should also like to inform you that the TS-FM Group can arrange for waste to be removed from work-sites for firms under contract to CERN, provided that the prior authorisation of the CERN Staff Member in charge of the contract is obtained and the relevant disposal/handling charges are paid. You are reminded that the selective sorting...

  8. Waste disposal

    CERN Multimedia

    2006-01-01

    We should like to remind you that you can have all commonplace, conventional waste (combustible, inert, wood, etc.) disposed of by the TS-FM Group. Requests for the removal of such waste should be made by contacting FM Support on tel. 77777 or by e-mail (Fm.Support@cern.ch). For requests to be acted upon, the following information must be communicated to FM Support: budget code to be debited for the provision and removal of the skip / container. type of skip required (1m3, 4 m3, 7 m3, 15 m3, 20 m3, 30 m3). nature of the waste to be disposed of (bulky objects, cardboard boxes, etc.). building concerned. details of requestor (name, phone number, department, group, etc.). We should also like to inform you that the TS-FM Group can arrange for waste to be removed from work-sites for firms under contract to CERN, provided that the prior authorisation of the CERN Staff Member in charge of the contract is obtained and the relevant disposal/handling charges are paid. You are reminded that the selective sorting o...

  9. Urban increments of gaseous and aerosol pollutants and their sources using mobile aerosol mass spectrometry measurements

    Science.gov (United States)

    Elser, Miriam; Bozzetti, Carlo; El-Haddad, Imad; Maasikmets, Marek; Teinemaa, Erik; Richter, Rene; Wolf, Robert; Slowik, Jay G.; Baltensperger, Urs; Prévôt, André S. H.

    2016-06-01

    Air pollution is one of the main environmental concerns in urban areas, where anthropogenic emissions strongly affect air quality. This work presents the first spatially resolved detailed characterization of PM2.5 (particulate matter with aerodynamic equivalent diameter daero ≤ 2.5 µm) in two major Estonian cities, Tallinn and Tartu. The measurements were performed in March 2014 using a mobile platform. In both cities, the non-refractory (NR)-PM2.5 was characterized by a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) using a recently developed lens which increases the transmission of super-micron particles. Equivalent black carbon (eBC) and several trace gases including carbon monoxide (CO), carbon dioxide (CO2), and methane (CH4) were also measured. The chemical composition of PM2.5 was found to be very similar in the two cities. Organic aerosol (OA) constituted the largest fraction, explaining on average about 52 to 60 % of the PM2.5 mass. Four sources of OA were identified using positive matrix factorization (PMF): hydrocarbon-like OA (HOA, from traffic emissions), biomass burning OA (BBOA, from biomass combustion), residential influenced OA (RIOA, probably mostly from cooking processes with possible contributions from waste and coal burning), and oxygenated OA (OOA, related to secondary aerosol formation). OOA was the major OA source during nighttime, explaining on average half of the OA mass, while during daytime mobile measurements the OA was affected by point sources and dominated by the primary fraction. A strong increase in the secondary organic and inorganic components was observed during periods with transport of air masses from northern Germany, while the primary local emissions accumulated during periods with temperature inversions. Mobile measurements offered the identification of different source regions within the urban areas and the assessment of the extent to which pollutants concentrations exceeded regional background

  10. Inertial classification of aerosols for size measurement

    International Nuclear Information System (INIS)

    Major inertial size classification techniques and devices have been reviewed. Principles of operation, advantages and limitations of each technique, precautions to be taken in design and operation of the devices are discussed with respect to their applications to nuclear aerosol analyses. Included in the review are sedimentation chambers, elutriators, cascade impactors, centrifuges and cyclones. Based on the comparison of various techniques, it has been concluded that spiral duct centrifuges and cascade impactors are suitable for measuring the aerosol size distribution for nuclear aerosol applications. It is also emphasized that because of the possible operational problems and the variations in performance resulting from sampling conditions, any inertial aerosol measurement device should be calibrated and evaluated under conditions as close as possible to the experimental conditions expected during their use

  11. Aerosol transport in severe reactor accidents

    International Nuclear Information System (INIS)

    Aerosol behaviour in the reactor containment was studied in the case of severe reactor accidents. The study was performed in a Nordic group during the years 1985 to 1988. Computer codes with different aerosol models were used for calculation of fission product transport and the results are compared. Experimental results from LACE, DEMONA and Marviken-V are compared with the calculations. The theory of aerosol nucleation and its influence on the fission product transport is discussed. The behaviour of hygroscopic aerosols is studied. The pool scrubbing models in the codes SPARC and SUPRA are reviewed and some knowledge in this field is assessed on the background of an international rewiew. (author) 60 refs

  12. Humidity Dependent Extinction of Clay Aerosols

    Science.gov (United States)

    Greenslade, M. E.; Attwood, A. R.

    2010-12-01

    Aerosols play an important role in the Earth’s radiative balance by directly scattering and absorbing radiation. The magnitude of aerosol forcing can be altered by changes in relative humidity which cause aerosol size, shape and refractive index to vary. To quantify these effects, a custom cavity ring down instrument operated at 532 nm with two sample channels measures aerosols extinction under dry conditions and at elevated humidity. The optical growth, fRH(ext), is determined as a ratio of the extinction cross section at high relative humidity to that under dry conditions. Three key clay components of mineral dust and mixtures of clay components with ammonium sulfate are investigated using this method. Experimentally obtained optical growth is compared with physical growth factors from the literature and our work determined using several different techniques. Further, Mie theory calculations based on published optical constants are compared with experimental results. Differences between theory and experiment will be discussed.

  13. Direct impact aerosol sampling by electrostatic precipitation

    Science.gov (United States)

    Braden, Jason D.; Harter, Andrew G.; Stinson, Brad J.; Sullivan, Nicholas M.

    2016-02-02

    The present disclosure provides apparatuses for collecting aerosol samples by ionizing an air sample at different degrees. An air flow is generated through a cavity in which at least one corona wire is disposed and electrically charged to form a corona therearound. At least one grounded sample collection plate is provided downstream of the at least one corona wire so that aerosol ions generated within the corona are deposited on the at least one grounded sample collection plate. A plurality of aerosol samples ionized to different degrees can be generated. The at least one corona wire may be perpendicular to the direction of the flow, or may be parallel to the direction of the flow. The apparatus can include a serial connection of a plurality of stages such that each stage is capable of generating at least one aerosol sample, and the air flow passes through the plurality of stages serially.

  14. Remote Sensing of Aerosol Properties during CARES

    Energy Technology Data Exchange (ETDEWEB)

    Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Flynn, Connor J.; Ferrare, R.; Hostetler, Chris A.; Hair, John; Jobson, Bertram Thomas

    2011-10-01

    One month of MFRSR data collected at two sites in the central California (USA) region during the CARES campaign are processed and the MFRSR-derived AODs at 500 nm wavelength are compared with available AODs provided by AERONET measurements. We find that the MFRSR and AERONET AODs are small ({approx}0.05) and comparable. A reasonable quantitative agreement between column aerosol size distributions (up to 2 um) from the MFRSR and AERONET retrievals is illustrated as well. Analysis of the retrieved (MFRSR and AERONET) and in situ measured aerosol size distributions suggests that the contribution of the coarse mode to aerosol optical properties is substantial for several days. The results of a radiative closure experiment performed for the two sites and one-month period show a favorable agreement between the calculated and measured broadband downwelling irradiances (bias does not exceed about 3 Wm-2), and thus imply that the MFRSR-derived aerosol optical properties are reasonable.

  15. Nanometer and ultrafine aerosols from radon radiolysis

    International Nuclear Information System (INIS)

    The ability of ionizing radiation to produce condensation nuclei aerosols in filtered air is well known. Recent studies have indicated that radiolysis results initially in the production of highly diffusive, nanometer-sized (5 nm) can then evolve by coagulation and growth processes. The nanometer nuclei are, however, poorly detected by condensation nuclei counters (CNCs) since CNC efficiencies drop sharply for particle sizesx molecular cluster aerosols from the decay of radon, and sulfuric acid nanometer nuclei and ultrafine aerosols from the radiolytic oxidation of SO2 in radon-air mixtures, were studied through wire screen-based size distribution measurements of the 218Po radioactivity associated with the aerosols. Comparisons with conventional diffusion battery-CNC derived number size distributions are also presented. (author)

  16. Aerosol Best Estimate Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, C; Turner, D; Koontz, A; Chand, D; Sivaraman, C

    2012-07-19

    The objective of the Aerosol Best Estimate (AEROSOLBE) value-added product (VAP) is to provide vertical profiles of aerosol extinction, single scatter albedo, asymmetry parameter, and Angstroem exponents for the atmospheric column above the Central Facility at the ARM Southern Great Plains (SGP) site. We expect that AEROSOLBE will provide nearly continuous estimates of aerosol optical properties under a range of conditions (clear, broken clouds, overcast clouds, etc.). The primary requirement of this VAP was to provide an aerosol data set as continuous as possible in both time and height for the Broadband Heating Rate Profile (BBHRP) VAP in order to provide a structure for the comprehensive assessment of our ability to model atmospheric radiative transfer for all conditions. Even though BBHRP has been completed, AEROSOLBE results are very valuable for environmental, atmospheric, and climate research.

  17. Aerosol emissions near a coal gasification plant in the Kosovo region, Yugoslavia

    Science.gov (United States)

    Boueres, Luis Carlos S.; Patterson, Ronald K.

    1981-03-01

    Ambient aerosol samples from the region of Kosovo, Yugoslavia, were collected and analyzed for their elemental composition in order to determine the effect on ambient air quality of Lurgi coal gasification carried out there using low BTU lignite. Low-volume aerosol samples were used to collect air particulate matter during May of 1979. These samplers were deployed at five sites near the Kosovo industrial complex which is comprised of coal gasifier, a coal-fired power plant and a fertilizer plant which uses the waste products from the gasifier and power plant. A total of 126 impactor sets and 10 week-long "streaker" filters were analyzed by PIXE at FSU for 16-18 elements providing a data base of approximately 16 000 elemental concentrations. Preliminary results are reported here with emphasis on the following elements: Si, S, Ca, Fe, Zn and Pb.

  18. Aerosol emissions near a coal gasification plant in the Kosovo region, Yugoslavia

    International Nuclear Information System (INIS)

    Ambient aerosol samples from the region of Kosovo, Yugoslavia, were collected and analyzed for their elemental composition in order to determine the effect on ambient air quality of Lurgi coal gasification carried out there using low BTU lignite. Low-volume aerosol samples were used to collect air particulate matter during May of 1979. These samplers were deployed at five sites near the Kosovo industrial complex which is comprised of coal gasifier, a coal-fired power plant and a fertilizer plant which uses the waste products from the gasifier and power plant. A total of 126 impactor sets and 10 week-long streaker filters were analyzed by PIXE at FSU for 16-18 elements providing a data base of approximately 16000 elemental concentrations. Preliminary resuls are reported here with emphasis on the following elements: Si, S, Ca, Fe, Zn and Pb. (orig.)

  19. Soluble Nutrient and Trace Metal Fluxes from Aerosol Dry Deposition to Elkhorn Slough, CA

    Science.gov (United States)

    Gray, E. T.; Paytan, A.; Haskins, J.

    2009-12-01

    Atmospheric deposition has been widely recognized as a source of pollutants and nutrients to coastal ecosystems. Specifically, deposition includes nitrogen compounds, sulfur compounds, mercury, pesticides, phosphate, trace metals and other toxic compounds that can travel great distances in aerosols. These components can come from both natural (volcanoes, mineral dust, forest fires) and anthropogenic (fossil fuels, chemical byproducts, incineration of waste) sources. These pollutants may affect ecosystem health and water quality with environmental impacts such as eutrophication, contaminated fish and harmful algal blooms. In this study we focus on dry deposition to Elkhorn Slough, California. Size fractionated aerosol samples (PM 2.5 and PM 10) collected continuously over a seven day period using a cascade impactor are used along with a deposition model to determine the soluble nutrient and trace metal fluxes on the Elkhorn Slough ecosystem. Atmospheric deposition inputs will be compared to other sources and their potential impact evaluated.

  20. The influence of salt aerosol on alpha radiation detection by WIPP continuous air monitors

    Energy Technology Data Exchange (ETDEWEB)

    Bartlett, W.T.; Walker, B.A. [Environmental Evaluation Group, Albuquerque, NM (United States)

    1997-08-01

    Waste Isolation Pilot Plant (WIPP) alpha continuous air monitor (CAM) performance was evaluated to determine if CAMs could detect accidental releases of transuranic radioactivity from the underground repository. Anomalous alpha spectra and poor background subtraction were observed and attributed to salt deposits on the CAM sampling filters. Microscopic examination of salt laden sampling filters revealed that aerosol particles were forming dendritic structures on the surface of the sampling filters. Alpha CAM detection efficiency decreased exponentially as salt deposits increased on the sampling filters, suggesting that sampling-filter salt was performing like a fibrous filter rather than a membrane filter. Aerosol particles appeared to penetrate the sampling-filter salt deposits and alpha particle energy was reduced. These findings indicate that alpha CAMs may not be able to detect acute releases of radioactivity, and consequently CAMs are not used as part of the WIPP dynamic confinement system. 12 refs., 12 figs., 1 tab.

  1. La-oxides as tracers for PuO2 to simulate contaminated aerosol behavior

    International Nuclear Information System (INIS)

    An analytical and experimental study was performed on the use of lanthanide oxides (La-oxides) as surrogates for plutonium oxides (PuO2) during simulated buried waste retrieval. This study determined how well the La-oxides move compared to PuO2 in aerosolized soils during retrieval scenarios. As part of the analytical study, physical properties of La-oxides and PuO2, such as molecular diameter, diffusivity, density, and molecular weight are compared. In addition, an experimental study was performed in which Idaho National Engineering Laboratory (INEL) soil, INEL soil with lanthanides, and INEL soil with plutonium were aerosolized and collected in filters. Comparison of particle size distribution parameters from this experimental study show similarity between INEL soil, INEL soil with lanthanides, and INEL soil with plutonium

  2. Composition and sources of organic tracers in aerosol particles of industrial central India

    Science.gov (United States)

    Giri, Basant; Patel, Khageshwar S.; Jaiswal, Nitin K.; Sharma, Saroj; Ambade, Balram; Wang, Wentao; Simonich, Staci L. Massey; Simoneit, Bernd R. T.

    2013-02-01

    Organic aerosols are important atmospheric components, and their formation and sources represent important aspects of urban air quality and health effects. Asia, including India, is the largest global source of aerosol particles due to regional natural advection (e.g. desert and soil dust) and anthropogenic activities (e.g. emissions from traffic, industry and burning of coal, biomass and agricultural waste) that generate vast amounts of particulate matter (PM) significantly contributing to climate change. This article reports on the distributions, concentrations, and sources of organic compounds (i.e., alkanes, carboxylic acids, carbonyl compounds, alcohols, plasticizers, PAHs, biomarkers) of PM in the ambient atmosphere of an extensively industrialized area of central India (Raipur, Chhattisgarh, a coal mega-burning region). The dominant components are emissions from fossil fuel utilization, burning of biomass and plastics, and fugitive sources. Speciation and variations of potential new tracer compounds identified are also described.

  3. Prague Aerosol Supersite, Suchdol (PASS, urban background)

    Czech Academy of Sciences Publication Activity Database

    Ždímal, Vladimír; Ondráček, Jakub; Zíková, Naděžda; Vodička, Petr; Makeš, Otakar; Řimnáčová, Daniela; Štefancová, Lucia; Šilhavý, J.; Smolík, Jiří; Schwarz, Jaroslav

    - : -, 2012, P286. [European Aerosol Confrernce EAC 2012. Granada (ES), 02.09.2012-07.09.2012] R&D Projects: GA ČR GAP209/11/1342 Grant ostatní: MF NF(CZ) A/CZ0046/2/2001; UFIREG(XE) 3CE288P3 Institutional support: RVO:67985858 Keywords : atmospheric aerosol * urban background Subject RIV: CF - Physical ; Theoretical Chemistry http://www.eac2012.com/EAC2012Book/3.html

  4. Photophoretic levitation of engineered aerosols for geoengineering

    OpenAIRE

    Keith, David W.

    2010-01-01

    Aerosols could be injected into the upper atmosphere to engineer the climate by scattering incident sunlight so as to produce a cooling tendency that may mitigate the risks posed by the accumulation of greenhouse gases. Analysis of climate engineering has focused on sulfate aerosols. Here I examine the possibility that engineered nanoparticles could exploit photophoretic forces, enabling more control over particle distribution and lifetime than is possible with sulfates, perhaps allowing clim...

  5. Aerosol fabrication methods for monodisperse nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xingmao; Brinker, C Jeffrey

    2014-10-21

    Exemplary embodiments provide materials and methods for forming monodisperse particles. In one embodiment, the monodisperse particles can be formed by first spraying a nanoparticle-containing dispersion into aerosol droplets and then heating the aerosol droplets in the presence of a shell precursor to form core-shell particles. By removing either the shell layer or the nanoparticle core of the core-shell particles, monodisperse nanoparticles can be formed.

  6. Improved Gridded Aerosol Data for India

    Energy Technology Data Exchange (ETDEWEB)

    Gueymard, C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sengupta, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-11-01

    Using point data from ground sites in and around India equipped with multiwavelength sunphotometers, as well as gridded data from space measurements or from existing aerosol climatologies, an improved gridded database providing the monthly aerosol optical depth at 550 nm (AOD550) and Angstrom exponent (AE) over India is produced. Data from 83 sunphotometer sites are used here as ground truth tocalibrate, optimally combine, and validate monthly gridded data during the period from 2000 to 2012.

  7. Application of aerosol technology in LMFBR design

    International Nuclear Information System (INIS)

    Aerosol technology is applied in several areas in the safety assessment of liquid metal fast breeder reactors. This paper discusses the application of this technology in the assessment of the Clinch River Breeder Reactor Plant. The importance of considering aerosol effects is discussed for sodium fires, the assessment of site suitability and the assessment of the consequences of accidents beyond the design base such as hypothetical core disruptive accidents. Areas in which further development work could have the most impact are indicated

  8. Development of a cavity enhanced aerosol albedometer

    OpenAIRE

    Zhao, W.; Xu, X.; Dong, M.; Chen, W.; X. Gu; Hu, C; Huang, Y.; Gao, X; Huang, W.; Zhang, W

    2014-01-01

    We report on the development of a cavity enhanced aerosol single scattering albedometer incorporating incoherent broad-band cavity-enhanced spectroscopy (IBBCEAS) approach and an integrating sphere (IS) for simultaneous in situ measurements of aerosol scattering and extinction coefficients in the exact same sample volume. The cavity enhanced albedometer employed a blue light-emitting diode (LED) based IBBCEAS approach for the measurement of wavelength-resolv...

  9. Evaluation of Aerosol Optical Depth by AERONET, MODIS and MISR over the Mediterranean and Middle East in 2006.

    Science.gov (United States)

    de Meij, Alexander; Lelieveld, Jos

    2010-05-01

    The objective of this study is to evaluate the spatial and temporal variation of the aerosol optical depth (AOD) and to identify the main characteristics of the aerosol episodes for the Mediterranean area, with the focus on the year 2006. We evaluate aerosol optical properties of MODIS and MISR instruments with AERONET. In general the yearly mean MODIS and MISR AOD is in good agreement with AERONET and the temporal AOD variation is also in good agreement. High AODs observed by AERONET, MODIS and MISR are caused by natural dust events or high anthropogenic aerosol concentrations in the combination with stagnant meteorological conditions. The comparison of MODIS and MISR aerosol optical properties with AERONET for June reveals that the AODs, Angstrom coefficients and single scattering albedos agree well with AERONET and indicate the presence of natural dust in the Mediterranean. In general MISR AOD is lower than MODIS AOD during summer. Comparing MODIS Aqua Deep Blue with MISR for June over the Saharan desert reveals some differences in the location and the maxima of the AOD values. The seasonal AOD variation by MISR over the Mediterranean and Middle East shows substantial differences in the AODs for each season. Higher dust loads during spring and autumn time in the eastern part of the Mediterranean. Biomass burning activities around the Black Sea during July and August (e.g. agricultural waste burning) cause high AODs and the particles are transported to the eastern part of the Mediterranean, because of the dominant northerly wind direction during summer.

  10. Environmental health hazards of e-cigarettes and their components: Oxidants and copper in e-cigarette aerosols

    International Nuclear Information System (INIS)

    To narrow the gap in our understanding of potential oxidative properties associated with Electronic Nicotine Delivery Systems (ENDS) i.e. e-cigarettes, we employed semi-quantitative methods to detect oxidant reactivity in disposable components of ENDS/e-cigarettes (batteries and cartomizers) using a fluorescein indicator. These components exhibit oxidants/reactive oxygen species reactivity similar to used conventional cigarette filters. Oxidants/reactive oxygen species reactivity in e-cigarette aerosols was also similar to oxidant reactivity in cigarette smoke. A cascade particle impactor allowed sieving of a range of particle size distributions between 0.450 and 2.02 μm in aerosols from an e-cigarette. Copper, being among these particles, is 6.1 times higher per puff than reported previously for conventional cigarette smoke. The detection of a potentially cytotoxic metal as well as oxidants from e-cigarette and its components raises concern regarding the safety of e-cigarettes use and the disposal of e-cigarette waste products into the environment. - Highlights: • E-cigarettes disposal is associated with environmental health hazard/pollution. • Oxidants associated with electronic cigarette components and aerosols. • Metal copper and nanoparticles detected in electronic cigarette aerosols. • Environmental disposal of e-cigarettes components must be regulated with guidelines. - An electronic cigarette with disposable cartomizer exhibits oxidant reactivity similar to conventional cigarettes and releases copper and other particles associated with its aerosols

  11. Aged organic aerosol in the Eastern Mediterranean: the Finokalia Aerosol Measurement Experiment – 2008

    Directory of Open Access Journals (Sweden)

    L. Hildebrandt

    2010-05-01

    Full Text Available Aged organic aerosol (OA was measured at a remote coastal site on the island of Crete, Greece during the Finokalia Aerosol Measurement Experiment-2008 (FAME-2008, which was part of the EUCAARI intensive campaign of May 2008. The site at Finokalia is influenced by air masses from different source regions, including long-range transport of pollution from continental Europe. A quadrupole aerosol mass spectrometer (Q-AMS was employed to measure the size-resolved chemical composition of non-refractory submicron aerosol (NR-PM1, and to estimate the extent of oxidation of the organic aerosol. Factor analysis was used to gain insights into the processes and sources affecting the OA composition. The particles were internally mixed and liquid. The largest fraction of the dry NR-PM1 sampled was ammonium sulfate and ammonium bisulfate, followed by organics and a small amount of nitrate. The variability in OA composition could be explained with two factors of oxygenated organic aerosol (OOA with differing extents of oxidation but similar volatility. Hydrocarbon-like organic aerosol (HOA was not detected. There was no statistically significant diurnal variation in the bulk composition of NR-PM1 such as total sulfate or total organic aerosol concentrations. However, the OA composition exhibited statistically significant diurnal variation with more oxidized OA in the afternoon. The organic aerosol was highly oxidized, regardless of the source region. Total OA concentrations also varied little with source region, suggesting that local sources had only a small effect on OA concentrations measured at Finokalia. The aerosol was transported for about one day before arriving at the site, corresponding to an OH exposure of approximately 4×1011 molecules cm−3 s. The constant extent of oxidation suggests that atmospheric aging results in a highly oxidized OA at these OH exposures, regardless of the aerosol source.

  12. Aged organic aerosol in the Eastern Mediterranean: the Finokalia Aerosol Measurement Experiment - 2008

    Science.gov (United States)

    Hildebrandt, L.; Engelhart, G. J.; Mohr, C.; Kostenidou, E.; Lanz, V. A.; Bougiatioti, A.; Decarlo, P. F.; Prevot, A. S. H.; Baltensperger, U.; Mihalopoulos, N.; Donahue, N. M.; Pandis, S. N.

    2010-05-01

    Aged organic aerosol (OA) was measured at a remote coastal site on the island of Crete, Greece during the Finokalia Aerosol Measurement Experiment-2008 (FAME-2008), which was part of the EUCAARI intensive campaign of May 2008. The site at Finokalia is influenced by air masses from different source regions, including long-range transport of pollution from continental Europe. A quadrupole aerosol mass spectrometer (Q-AMS) was employed to measure the size-resolved chemical composition of non-refractory submicron aerosol (NR-PM1), and to estimate the extent of oxidation of the organic aerosol. Factor analysis was used to gain insights into the processes and sources affecting the OA composition. The particles were internally mixed and liquid. The largest fraction of the dry NR-PM1 sampled was ammonium sulfate and ammonium bisulfate, followed by organics and a small amount of nitrate. The variability in OA composition could be explained with two factors of oxygenated organic aerosol (OOA) with differing extents of oxidation but similar volatility. Hydrocarbon-like organic aerosol (HOA) was not detected. There was no statistically significant diurnal variation in the bulk composition of NR-PM1 such as total sulfate or total organic aerosol concentrations. However, the OA composition exhibited statistically significant diurnal variation with more oxidized OA in the afternoon. The organic aerosol was highly oxidized, regardless of the source region. Total OA concentrations also varied little with source region, suggesting that local sources had only a small effect on OA concentrations measured at Finokalia. The aerosol was transported for about one day before arriving at the site, corresponding to an OH exposure of approximately 4×1011 molecules cm-3 s. The constant extent of oxidation suggests that atmospheric aging results in a highly oxidized OA at these OH exposures, regardless of the aerosol source.

  13. Operational aerosol and dust storm forecasting

    International Nuclear Information System (INIS)

    The U. S. Navy now conducts operational forecasting of aerosols and dust storms on global and regional scales. The Navy Aerosol Analysis and Prediction System (NAAPS) is run four times per day and produces 6-day forecasts of sulfate, smoke, dust and sea salt aerosol concentrations and visibility for the entire globe. The Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS (registered) ) is run twice daily for Southwest Asia and produces 3-day forecasts of dust, smoke, and visibility. The graphical output from these models is available on the Internet (www.nrlmry.navy.mil/aerosol/). The aerosol optical properties are calculated for each specie for each forecast output time and used for sea surface temperature (SST) retrieval corrections, regional electro-optical (EO) propagation assessments, and the development of satellite algorithms. NAAPS daily aerosol optical depth (AOD) values are compared with the Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS) AOD values. Visibility forecasts are compared quantitatively with surface synoptic reports.

  14. Aerosol penetration inside HEPA filtration media

    International Nuclear Information System (INIS)

    Attempts made to modelize changes in high-efficiency particulate air (HEPA) filter pressure drop as a function of such parameters as the amount of aerosol collected, which also take account of filtering medium characteristics, those of the filtered aerosol and the filtration velocity, have always been limited by a lack of knowledge of the distribution of particles within the medium. For the last few years, a method, developed over 25 years ago to study the distribution of Radon daughters within filter media made of cellulose fibers, has been reused and applied to radioactive and fluorescent aerosols penetration studies. This method enables determination of aerosol distribution on the surface and inside the filter medium by peeling away successive layers using an adhesive tape and measuring the specific amounts removed each time. Knowledge of aerosol penetration within the filter has revealed that, for a give aerosol, particle distribution inside the filter rapidly decreased exponentially and that fixation on the filter's front surface rapidly superseded penetration inside the medium. The deposit profiles thus measured have made it possible to propose a model for determining the rate of filter pressure drop increase that closely agrees with experimental results

  15. SCIAMACHY stratospheric aerosol extinction profile retrieval

    Directory of Open Access Journals (Sweden)

    G. Taha

    2010-11-01

    Full Text Available The Ozone Mapper and Profiler Suite Limp Profiler (OMPS/LP algorithm is used to retrieve ozone and aerosol profiles using a series of 120 SCIAMACHY limb measurements collocated with SAGE II solar occultation events. The primary goal of the study is to ascertain the capability of the OMPS/LP retrieval algorithm to accurately retrieve the vertical distribution of stratospheric aerosol extinction coefficient so as to better account for aerosol effects in the ozone profiling retrieval process. Using simulated radiances, we show that the aerosol extinction coefficient can be retrieved from limb scatter measurements within 5% and a standard deviation better than 15%, which is more than sufficient to improve the OMPS/LP ozone products to be used as Environmental Data Records. We also illustrate the ability of SCIAMACHY limb measurements to retrieve stratospheric aerosol profiles with accuracy comparable to other instruments. The retrieved aerosol profiles agree with collocated SAGE II measurements on average to within 25%, with a standard deviation of 35%.

  16. Radiation monitoring by radiation effect of aerosol

    International Nuclear Information System (INIS)

    The high energy and high intensity accelerator facilities need the radiation monitoring with temporal and spatial resolutions. Numerical estimations are made for the radiation monitoring using the sampling method of aerosol Alanine. The aerosol Alanine put into the monitoring area through the duct. The intensity of radicals in the collected throughput Alanine of about 50 mg after passing through the monitoring area is measured by the ESR (Electron Spin Resonance) method. Key parameters in the system are the aerosol particle diameter and its intensity, the duct diameter and length, and the aerosol flow rate inside the duct. The maximum dose rate more than 108 Gy/h is possible to measure assuming the duct of 100 cm2 in area and 10 m in length, and the aerosol flow rate of 1000 L/min. The temporal resolution of the order of minutes is obtainable when the aerosol particle size is 0.1 μm. As a result of numerical estimation based on empirical simulations, it is to be promising to apply a proposed scheme to the radiation monitoring for accelerator fields. (Y. Tanaka)

  17. Investigation on aerosol transport in containment cracks

    International Nuclear Information System (INIS)

    Under severe accident conditions, the containment leak-tightness could be threatened by energetic phenomena that could yield a release to the environment of nuclear aerosols through penetrating concrete cracks. As few data are presently available to quantify this aerosol leakage, a specific action was launched in the framework of the Santar Project of the European 6th Framework Programme. In this context, both theoretical and experimental investigations have been managed to develop a model that can readily be applied within a code like Aster (Accident Source Term Evaluation Code). Particle diffusion, settling, turbulent deposition, diffusiophoresis and thermophoresis have been considered as deposition mechanisms inside the crack path. They have been encapsulated in numerical models set up to reproduce experiments with small tubes and capillaries and simulate the plug formation. Then, an original lagrangian approach has been used to evaluate the crack retention under typical PWR accident conditions, comparing its predictions with those given by the eulerian approach implemented in the ECART code. On the experimental side, the paper illustrates an aerosol production and measurement system developed to validate aerosol deposition models into cracks and the results that can be obtained: a series of tests were performed with monodispersed fluorescein aerosols injected into a cracked concrete sample. A key result that should be further explored refers to the high enhancement of aerosol retention that could be due to steam condensation. Recommendations concerning future experimentation are also given in the paper. (author)

  18. Aerosols, clouds and their climatic impacts

    Energy Technology Data Exchange (ETDEWEB)

    Kulmala, M.; Laaksonen, A.; Korhonen, P. [Helsinki Univ. (Finland). Dept. of Physics

    1995-12-31

    The increasing atmospheric concentrations of greenhouse gases such as carbon dioxide and methane may drive a significant warming of the earth`s climate. However, a topic of more recent attention is the possibility that increased atmospheric concentrations of aerosol particles might drive a cooling of the planet. There are two distinct cooling mechanisms related to the enhanced concentrations of aerosol particles: the increase in the direct reflection of solar radiation (the direct effect), and the increase in cloud reflectivity caused by greater numbers of cloud condensation nuclei available (the indirect effect). Aerosols and clouds play a major role in the scattering and absorption of radiation in the Earth`s atmosphere. Locally the net effect can vary because of different kinds of surfaces. But according to measurements, the global net effect of clouds (and aerosols) on the atmosphere is net cooling and thus in opposition to the effect of greenhouse gases. The prediction of the future evolution of the climate involves substantial uncertainties. Clouds have a major effect on the radiation balance of the Earth and the prediction of amount and radiative properties of clouds is very difficult. Also the formation mechanisms and residence times of aerosol particles in the atmosphere involve large uncertainties. Thus the most serious difficulties arise in the area of the physics of clouds and aerosols

  19. Physical properties of aerosols at Maitri, Antarctica

    Indian Academy of Sciences (India)

    C G Deshpande; A K Kamra

    2004-03-01

    Measurements of the submicron aerosol size distribution made at the Indian Antarctic station, Maitri (70° 45′S, 11° 44′E) from January 10th to February 24th, 1997, are reported. Total aerosol concentrations normally range from 800 to 1200 particles cm-3 which are typical values for the coastal stations at Antarctica in summer. Aerosol size distributions are generally trimodal and open- ended with a peak between 75 and 133nm and two minima at 42 and 420 nm. Size distributions remain almost similar for several hours or even days in absence of any meteorological disturbance. Total aerosol concentration increases by approximately an order of magnitude whenever a low pressure system passes over the station. Based on the evolution of aerosol size-distributions during such aerosol enhancement periods, three types of cases have been identified. The nucleation mode in all three cases has been suggested to result from the photochemical conversion of the DMS emissions transported either by the marine air or by the air from the ice-melt regions around Maitri. Subsidence of midtropospheric air during the weakening of radiative inversion is suggested as a possible source of the nucleation mode particles in the third case. Growth of the nucleation mode particles by condensation, coagulation and/or by cloud processes has been suggested to be responsible for other modes in size distributions.

  20. Aerosol and air pollution size distribution

    Science.gov (United States)

    Shani, Gad; Haccoun, A.; Kushelevsky, A.

    The size distribution of aerosols was measured in a moderately industrial city, in a semi-arid zone on the Negev desert border. The aerosols in the city of Beer Sheva are from two sources: the dust coming from the desert and urban pollution. The size measurements were done with a cascade impactor. The elemental content of the aerosols was investigated by neutron activation analysis and X-ray fluorescence. The main elements of the dust are: Ca, Si, Fe, Na and the trace elements are: Sc, Se, La, Sm, Hf and others. The main elements of the urban pollution are S, Br, Pb, Cl, Hg and others. It was found that the elements belonging to each group can easily be classified by the size distribution. The analytical consideration of the aerosol size distribution of each group are discussed and two corresponding analytical expressions are suggested. It is shown that aerosols originating in the dust have a hump shape distribution around ~ 4μm, and those originating in urban pollution have a distribution decreasing with increasing aerosol diameter. Many examples are given to prove the conclusions.

  1. Study of photolytic aerosols at stratospheric pressures

    International Nuclear Information System (INIS)

    An experimental study of photolytic aerosol formation at stratospheric pressure (60 Torr) and laboratory temperature, was carried out previous to the exact simulation of photolytic aerosol formation in real stratospheric conditions. An experimental simulation device, techniques of generation of known mixtures of inert gases with SO2 and NOsub(x) traces at low concentration (below 1 ppm volume) and H2O traces (a few ppm), and techniques for the determination and counting of aerosol particles at low pressures were perfected. The following results were achieved: the rate of vapor condensation on nuclei was reduced when total pressure decreased. At low pressure the working of condensation nuclei counters and the formation of photolytic aerosols is influenced by this phenomenon. An explanation is proposed, as well as means to avoid this unpleasant effect on the working of nuclei counters at low pressure. No photolytic aerosol production was ascertained at 60 Torr when water concentration was below 100 ppm whatever the concentration of SO2 or NOsub(x) traces. With water concentration below 1200ppm and SO2 trace concentration below 1ppm, the aerosol particles produced could not consist of sulfuric acid drops but probably of nitrosyl sulfate acide crystals

  2. The aerosol penetration through an electret fibrous filter

    Institute of Scientific and Technical Information of China (English)

    Jiang Wei; Cheung Chun-Shun; Chan Cheong-Ki; Zhu Chao

    2006-01-01

    The aim of this paper is to present a theoretical study of the aerosol penetration through an electret fibrous filter, using a numerical approach. The aerosol sizes considered in this study were in the submicron range, and in the numerical model, the conventional mechanical mechanisms (impaction, interception, diffusion and gravitationally settling) were taken into consideration along with the electrostatic mechanisms, including the Coulombic and dielectrophoretic effects. The aerosol penetration through an electret fibrous filter is heavily dependent on the aerosol penetration of a single fibre. The aerosol penetration through a single electret fibre under various filtration conditions was calculated. The effects of aerosol diameter, aerosol and fibre charge state, face velocity, packing density and aerosol dielectric constant on the aerosol penetration were investigated.

  3. Aerosol-Based Cell Therapy for Treatment of Lung Diseases.

    Science.gov (United States)

    Kardia, Egi; Halim, Nur Shuhaidatul Sarmiza Abdul; Yahaya, Badrul Hisham

    2016-01-01

    Aerosol-based cell delivery technique via intratracheal is an effective route for delivering transplant cells directly into the lungs. An aerosol device known as the MicroSprayer(®) Aerosolizer is invented to transform liquid into an aerosol form, which then can be applied via intratracheal administration for drug delivery. The device produces a uniform and concentrated distribution of aerosolized liquid. Using the capability of MicroSprayer(®) Aerosolizer to transform liquid into aerosol form, our group has designed a novel method of cell delivery using an aerosol-based technique. We have successfully delivered skin-derived fibroblast cells and airway epithelial cells into the airway of a rabbit with minimum risk of cell loss and have uniformly distributed the cells into the airway. This chapter illustrates the application of aerosol device to deliver any type of cells for future treatment of lung diseases. PMID:27062596

  4. A pre-processor of trace gases and aerosols emission fields for regional and global atmospheric chemistry models

    OpenAIRE

    Freitas, S. R.; Longo, K. M.; Alonso, M. F.; M. Pirre; Marecal, V.; Grell, G; R. Stockler; R. F. Mello; Sánchez Gácita, M.

    2010-01-01

    The pre-processor PREP-CHEM-SRC presented in the paper is a comprehensive tool aiming at preparing emissions fields of trace gases and aerosols for use in regional or global transport models. The emissions considered are urban/industrial, biogenic, biomass burning, volcanic, biofuel use and burning from agricultural waste sources from most recent databases or from satellite fire detections for biomass burning. A plumerise model is used to derive the height of smoke emissions from satel...

  5. An AERONET-based aerosol classification using the Mahalanobis distance

    Science.gov (United States)

    Hamill, Patrick; Giordano, Marco; Ward, Carolyne; Giles, David; Holben, Brent

    2016-09-01

    We present an aerosol classification based on AERONET aerosol data from 1993 to 2012. We used the AERONET Level 2.0 almucantar aerosol retrieval products to define several reference aerosol clusters which are characteristic of the following general aerosol types: Urban-Industrial, Biomass Burning, Mixed Aerosol, Dust, and Maritime. The classification of a particular aerosol observation as one of these aerosol types is determined by its five-dimensional Mahalanobis distance to each reference cluster. We have calculated the fractional aerosol type distribution at 190 AERONET sites, as well as the monthly variation in aerosol type at those locations. The results are presented on a global map and individually in the supplementary material. Our aerosol typing is based on recognizing that different geographic regions exhibit characteristic aerosol types. To generate reference clusters we only keep data points that lie within a Mahalanobis distance of 2 from the centroid. Our aerosol characterization is based on the AERONET retrieved quantities, therefore it does not include low optical depth values. The analysis is based on "point sources" (the AERONET sites) rather than globally distributed values. The classifications obtained will be useful in interpreting aerosol retrievals from satellite borne instruments.

  6. Genesis of elevated aerosol loading over the Indian region

    Science.gov (United States)

    Prijith, S. S.; Rao, P. V. N.; Mohan, Mannil

    2016-05-01

    Elevated aerosols assume importance as the diabatic heating due to aerosol absorption is more intense at higher altitudes where the atmosphere becomes thinner. Indian region, especially its central and northern latitudes, experiences significant loading of elevated aerosols during pre-monsoon and summer months. Genesis of elevated aerosol loading over Indian region is investigated in the present study, using multi-year satellite observations from Cloud Aerosol Lidar with Orthogonal Polarization (CALIOP) and Moderate Resolution Imaging Spectroradiometer (MODIS) along with reanalysis winds from MERRA. Central India is observed to have prominent aerosols loading at higher altitudes during pre-monsoon season, whereas it is during summer months over north-west India. Further analysis reveals that the elevated aerosols over Indian region in pre-monsoon and summer months are significantly contributed by transported mineral dust from the arid continental regions at west. In addition to the mineral dust advection, aerosols at higher altitudes over Indian region are enriched by strong convection and associated vertical transport of surface level aerosols. Vertical transport of aerosols observed over Indian region during pre-monsoon and summer months is aided by intense convergence at the surface level and divergence at the upper level. Moreover, aerosol source/sink strength estimated using aerosol flux continuity equation show significant aerosol production over central India during pre-monsoon. Strong vertical transport prevails during pre-monsoon uplifts the locally produced aerosols, with considerable anthropogenic fraction, to higher altitudes where their impacts would be more intense.

  7. Transmission electron microscopy study of aerosol particles from the brown hazes in northern China

    Science.gov (United States)

    Li, Weijun; Shao, Longyi

    2009-05-01

    Airborne aerosol collections were performed in urban areas of Beijing that were affected by regional brown haze episodes over northern China from 31 May to 12 June 2007. Morphologies, elemental compositions, and mixing states of 810 individual aerosol particles of different sizes were obtained by transmission electron microscopy coupled with energy-dispersive X-ray spectrometry. The phases of some particles were verified using selected-area electron diffraction. Aerosol particle types less than 10 μm in diameter include mineral, complex secondary (Ca-S, K-, and S-rich), organic, soot, fly ash, and metal (Fe-rich and Zn-bearing). Most soot, fly ash, and organic particles are less than 2 μm in diameter. Approximately 84% of the analyzed mineral particles have diameters between 2 and 10 μm, while 81% of the analyzed complex secondary and metal particles are much smaller, from 0.1 to 2 μm. Trajectory analysis with fire maps show that southerly air masses arriving at Beijing have been transported through many agricultural biomass burning sites and heavy industrial areas. Spherical fly ash and Fe-rich particles were from industrial emissions, and abundant K-rich and organic particles likely originated from field burning of crop residues. Abundant Zn-bearing particles are associated with industrial activities and local waste incinerators. On the basis of the detailed analysis of 443 analyzed aerosol particles, about 70% of these particles are internally mixed with two or more aerosol components from different sources. Most mineral particles are covered with visible coatings that contain N, O, Ca (or Mg), minor S, and Cl. K- and S-rich particles tend to be coagulated with fly ash, soot, metal, and fine-grained mineral particles. Organic materials internally mixed with K- and S-rich particles can be their inclusions and coatings.

  8. Chemical characterization of secondary organic aerosol constituents from isoprene ozonolysis in the presence of acidic aerosol

    Science.gov (United States)

    Riva, Matthieu; Budisulistiorini, Sri Hapsari; Zhang, Zhenfa; Gold, Avram; Surratt, Jason D.

    2016-04-01

    Isoprene is the most abundant non-methane hydrocarbon emitted into Earth's atmosphere and is predominantly derived from terrestrial vegetation. Prior studies have focused largely on the hydroxyl (OH) radical-initiated oxidation of isoprene and have demonstrated that highly oxidized compounds, such as isoprene-derived epoxides, enhance the formation of secondary organic aerosol (SOA) through heterogeneous (multiphase) reactions on acidified sulfate aerosol. However, studies on the impact of acidified sulfate aerosol on SOA formation from isoprene ozonolysis are lacking and the current work systematically examines this reaction. SOA was generated in an indoor smog chamber from isoprene ozonolysis under dark conditions in the presence of non-acidified or acidified sulfate seed aerosol. The effect of OH radicals on SOA chemical composition was investigated using diethyl ether as an OH radical scavenger. Aerosols were collected and chemically characterized by ultra performance liquid chromatography/electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-QTOFMS) and gas chromatography/electron impact ionization-mass spectrometry (GC/EI-MS). Analysis revealed the formation of highly oxidized compounds, including organosulfates (OSs) and 2-methylterols, which were significantly enhanced in the presence of acidified sulfate seed aerosol. OSs identified in the chamber experiments were also observed and quantified in summertime fine aerosol collected from two rural locations in the southeastern United States during the 2013 Southern Oxidant and Aerosol Study (SOAS).

  9. Effect of Aerosol Size and Hygroscopicity on Aerosol Optical Depth in the Southeastern United States

    Science.gov (United States)

    Brock, Charles; Wagner, Nick; Gordon, Timothy

    2016-04-01

    Aerosol optical depth (AOD) is affected by the size, optical characteristics, and hygroscopicity of particles, confounding attempts to link remote sensing observations of AOD to measured or modeled aerosol mass concentrations. In situ airborne observations of aerosol optical, chemical, microphysical and hygroscopic properties were made in the southeastern United States in the daytime in summer 2013. We use these observations to constrain a simple model that is used to test the sensitivity of AOD to the various measured parameters. As expected, the AOD was found to be most sensitive to aerosol mass concentration and to aerosol water content, which is controlled by aerosol hygroscopicity and the ambient relative humidity. However, AOD was also fairly sensitive to the mean particle diameter and the width of the size distribution. These parameters are often prescribed in global models that use simplified modal parameterizations to describe the aerosol, suggesting that the values chosen could substantially bias the calculated relationship between aerosol mass and optical extinction, AOD, and radiative forcing.

  10. Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

    Energy Technology Data Exchange (ETDEWEB)

    Turner, David, D.; Ferrare, Richard, A.

    2011-07-06

    The 'Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds' project focused extensively on the analysis and utilization of water vapor and aerosol profiles derived from the ARM Raman lidar at the Southern Great Plains ARM site. A wide range of different tasks were performed during this project, all of which improved quality of the data products derived from the lidar or advanced the understanding of atmospheric processes over the site. These activities included: upgrading the Raman lidar to improve its sensitivity; participating in field experiments to validate the lidar aerosol and water vapor retrievals; using the lidar aerosol profiles to evaluate the accuracy of the vertical distribution of aerosols in global aerosol model simulations; examining the correlation between relative humidity and aerosol extinction, and how these change, due to horizontal distance away from cumulus clouds; inferring boundary layer turbulence structure in convective boundary layers from the high-time-resolution lidar water vapor measurements; retrieving cumulus entrainment rates in boundary layer cumulus clouds; and participating in a field experiment that provided data to help validate both the entrainment rate retrievals and the turbulent profiles derived from lidar observations.

  11. Method of measuring aerosol particles using automated mobility-classified aerosol detector

    OpenAIRE

    Russell, Lynn M.; Flagan, Richard C.; Zhang, Shou-Hua

    1999-01-01

    An aerosol detection system for measuring particle number distribution with respect to particle dimension in an aerosol sample. The system includes an alternating dual-bag sampler, a radially classified differential mobility analyzer, and a condensation nucleus counter. Pressure variations in sampling are compensated by feedback control of volumetric flow rates.

  12. Characterization of urban aerosol using aerosol mass spectrometry and proton nuclear magnetic resonance spectroscopy

    Science.gov (United States)

    Cleveland, M. J.; Ziemba, L. D.; Griffin, R. J.; Dibb, J. E.; Anderson, C. H.; Lefer, B.; Rappenglück, B.

    2012-07-01

    Particulate matter was measured during August and September of 2006 in Houston as part of the Texas Air Quality Study II Radical and Aerosol Measurement Project. Aerosol size and composition were determined using an Aerodyne quadrupole aerosol mass spectrometer. Aerosol was dominated by sulfate (4.1 ± 2.6 μg m-3) and organic material (5.5 ± 4.0 μg m-3), with contributions of organic material from both primary (˜32%) and secondary (˜68%) sources. Secondary organic aerosol appears to be formed locally. In addition, 29 aerosol filter samples were analyzed using proton nuclear magnetic resonance (1H NMR) spectroscopy to determine relative concentrations of organic functional groups. Houston aerosols are less oxidized than those observed elsewhere, with smaller relative contributions of carbon-oxygen double bonds. These particles do not fit 1H NMR source apportionment fingerprints for identification of secondary, marine, and biomass burning organic aerosol, suggesting that a new fingerprint for highly urbanized and industrially influenced locations be established.

  13. Possible Relations between Organic Aerosol Analysed by Aerosol Mass Spetrometer and EC/OC Analyzer

    Czech Academy of Sciences Publication Activity Database

    Vodička, Petr; Makeš, Otakar; Kubelová, Lucie; Schwarz, Jaroslav; Ždímal, Vladimír

    - : -, 2015, 234 /2053/. ISBN N. [Goldschmidt Conference /25./. Prague (CZ), 16.08.2015-21.08.2015] R&D Projects: GA ČR GAP209/11/1342 EU Projects: European Commission(XE) H2020:654109 Institutional support: RVO:67985858 Keywords : carbonaceous aerosols * aerosol data * analyzer Subject RIV: CF - Physical ; Theoretical Chemistry

  14. Evaluation of the discmini personal aerosol monitor for submicrometer sodium chloride and metal aerosols

    Science.gov (United States)

    Mills, Jessica Breyan

    This work evaluated the robust, lightweight DiSCmini (DM) aerosol monitor for its ability to measure the concentration and mean diameter of submicrometer aerosols. Tests were conducted with monodispersed and polydispersed aerosols composed of two particle types (sodium chloride, NaCl, and spark generated metal particles, which simulate particles found in welding fume) at three different steady-state concentration ranges (Low, 104 particles/cm3). Particle number concentration, lung deposited surface area (LDSA) concentration, and mean size measured with the DM were compared to those measured with reference instruments, a scanning mobility particle sizer (SMPS) and a handheld condensation particle counter (CPC). Particle number concentrations measured with the DM were within 16% of those measured by the CPC for polydispersed aerosols. Poorer agreement was observed for monodispersed aerosols (+/-35% for most tests and +101% for 300-nm NaCl). LDSA concentrations measured by the DM were 96% to 155% of those estimated with the SMPS. The geometric mean diameters measured with the DM were within 30% of those measured with the SMPS for monodispersed aerosols and within 25% for polydispersed aerosols (except for the case when the aerosol contained a substantial number of particles larger than 300 nm). The accuracy of the DM is reasonable for particles smaller than 300 nm but caution should be exercised when particles larger than 300 nm are present.

  15. The DRAGON aerosol research facility to study aerosol behaviour for reactor safety applications

    International Nuclear Information System (INIS)

    During a severe accident in a nuclear power plant fission products are expected to be released in form of aerosol particles and droplets. To study the behaviour of safety relevant reactor components under aerosol loads and prototypical severe accident conditions the multi-purpose aerosol generation facility DRAGON is used since 1994 for several projects. DRAGON can generate aerosol particles by the evaporation-condensation technique using a plasma torch system, fluidized bed and atomization of particles suspended in a liquid. Soluble, hygroscopic aerosol (i.e. CsOH) and insoluble aerosol particles (i.e. SnO2, TiO2) or mixtures of them can be used. DRAGON uses state-of-the-art thermal-hydraulic, data acquisition and aerosol measurement techniques and is mainly composed of a mixing chamber, the plasma torch system, a steam generator, nitrogen gas and compressed air delivery systems, several aerosol delivery piping, gas heaters and several auxiliary systems to provide vacuum, coolant and off-gas treatment. The facility can be operated at system pressure of 5 bars, temperatures of 300 deg. C, flow rates of non-condensable gas of 900 kg/h and steam of 270 kg/h, respectively. A test section under investigation is attached to DRAGON. The paper summarizes and demonstrates with the help of two project examples the capabilities of DRAGON for reactor safety studies. (authors)

  16. Use of multi-element tracers to source apportion mercury in south Florida aerosols

    Science.gov (United States)

    Graney, Joseph R.; Dvonch, J. Timothy; Keeler, Gerald J.

    The relative importance of local sources of mercury (Hg) in aerosols from urban areas in south Florida in relation to regional or global sources transported to the Everglades was investigated using a multi-element tracer approach. The sources of metals and Hg within aerosols were determined by integrating the collection of aerosols at seven locations with meteorology, source sampling, and statistical analysis. Sources include sea spray, soil dust from local carbonate bedrock and long range Saharan dust transport, regional scale transport of sulfate aerosols, and local point sources including oil-fired power plants, medical and waste incineration, and cement kilns. Using a principal components analysis-multiple linear regression (PCA-MLR) approach, 80% of the Hg in particulate form at the Thompson Park Everglades receptor site (THP) could be attributed to local sources. The key to the success of the source attribution at THP was collection of samples on a 12-h sampling basis in order to account for diurnal changes in meteorological conditions in south Florida associated with land-sea breeze development. Fifty-six±7% of the particulate Hg at THP was associated with elevated Zn concentrations which source sampling and surface meteorology indicate as emissions from municipal waste incineration located southeast of THP. Another 14±5% of the particulate Hg was associated with elevated Cu and Pb concentrations from sources SSE of THP. Eleven±1% of the particulate Hg originated from medical waste incineration sources and was associated with elevated levels of Cl and rapid SE to NW transport. Elevated concentrations of Si, Al, Fe, Mn, and K occurred on the same days at all sites, following passage of tropical storms over south Florida. PCA grouped these elements within a factor that is likely Saharan dust in origin, only 12±2% of the particulate Hg at THP could be attributed to this non-local source. Because the majority of the particulate Hg at THP can be attributed to

  17. Atmospheric aerosols: Their Optical Properties and Effects (supplement)

    Science.gov (United States)

    1976-01-01

    A digest of technical papers is presented. Topics include aerosol size distribution from spectral attenuation with scattering measurements; comparison of extinction and backscattering coefficients for measured and analytic stratospheric aerosol size distributions; using hybrid methods to solve problems in radiative transfer and in multiple scattering; blue moon phenomena; absorption refractive index of aerosols in the Denver pollution cloud; a two dimensional stratospheric model of the dispersion of aerosols from the Fuego volcanic eruption; the variation of the aerosol volume to light scattering coefficient; spectrophone in situ measurements of the absorption of visible light by aerosols; a reassessment of the Krakatoa volcanic turbidity, and multiple scattering in the sky radiance.

  18. Radioactive waste

    International Nuclear Information System (INIS)

    Focusing on radioactive waste management and disposal policies in the United Kingdom, Sweden and the Federal Republic of Germany, this book gives a detailed historical account of the policy process in these three countries, and draws out the implications for theory and public policy. This comparative approach underlines how profoundly different the policy process has been in different countries. By comparing the evolution of policy in three countries, fundamental questions about the formation and resolution of technical decisions under uncertainty are clarified. The analysis of nuclear strategy, the politics of nuclear power, and the shifting emphasis of government regulation redefines the issue of radwaste management and sets it at the heat of the current debate about power, the environment and society. The combination of up-to-date technological assessment with an account of the social and political implications of radwaste management makes'Radioactive Waste'particularly useful to students of environmental studies, geography and public administration. (author)

  19. Evaluation of AY/AZ tank farm ventilation system during aging waste retrieval operations

    International Nuclear Information System (INIS)

    Waste Management is currently planning to demonstrate mobilization of radioactive waste sludges in Tank 101-AZ beginning in October 1991. The retrieval system being designed will utilize mixer pumps that generate high-velocity, high-volume submerged liquid jets to mobilize settled solids. There is concern that these jets may also generate radioactive aerosols, some of which may be carried into the tank Ventilation system. The purpose of this study is to determine if the current AY/AZ ventilation system or the proposed ventilation system upgrade (Project W-030) will provide adequate deentrainment of liquid and solid aerosols during mixer pump operations, or if the radioactive aerosols will overload the HEPA filters

  20. Wasteful Labeling

    OpenAIRE

    Mahenc, Philippe

    2009-01-01

    The role of labeling is to solve the adverse selection problem caused by unsubstantiated claims from firms. The problem however is likely to remain unsolved if the labeling agency is not trustworthy.The agency can be suspected to divert the fees charged for labeling from their primary purpose of collecting information in order to raise excessive revenue. This paper addresses this issue and shows that labeling may be wasteful if the agency is likely to be untrustworthy. To award firms green la...

  1. Note: Design and development of wireless controlled aerosol sampling network for large scale aerosol dispersion experiments

    Science.gov (United States)

    Gopalakrishnan, V.; Subramanian, V.; Baskaran, R.; Venkatraman, B.

    2015-07-01

    Wireless based custom built aerosol sampling network is designed, developed, and implemented for environmental aerosol sampling. These aerosol sampling systems are used in field measurement campaign, in which sodium aerosol dispersion experiments have been conducted as a part of environmental impact studies related to sodium cooled fast reactor. The sampling network contains 40 aerosol sampling units and each contains custom built sampling head and the wireless control networking designed with Programmable System on Chip (PSoC™) and Xbee Pro RF modules. The base station control is designed using graphical programming language LabView. The sampling network is programmed to operate in a preset time and the running status of the samplers in the network is visualized from the base station. The system is developed in such a way that it can be used for any other environment sampling system deployed in wide area and uneven terrain where manual operation is difficult due to the requirement of simultaneous operation and status logging.

  2. Containment aerosol behaviour simulation studies in the BARC nuclear aerosol test facility

    International Nuclear Information System (INIS)

    A Nuclear Aerosol Test Facility (NATF) has been built and commissioned at Bhabha Atomic Research Centre to carry out simulation studies on the behaviour of aerosols released into the reactor containment under accident conditions. This report also discusses some new experimental techniques for estimation of density of metallic aggregates. The experimental studies have shown that the dynamic densities of aerosol aggregates are far lower than their material densities as expected by the well-known fractal theory of aggregates. In the context of codes, this has significant bearing in providing a mechanistic basis for the input density parameter used in estimating the aerosol evolution characteristics. The data generated under the quiescent and turbulent conditions and the information on aggregate densities are now being subjected to the validation of the aerosol behaviour codes. (author)

  3. MORPHOLOGY OF BLACK CARBON AEROSOLS AND UBIQUITY OF 50-NANOMETER BLACK CARBON AEROSOLS IN THE ATMOSPHERE

    Institute of Scientific and Technical Information of China (English)

    Fengfu Fu; Liangjun Xu; Wei Ye; Yiquan Chen; Mingyu Jiang; Xueqin Xu

    2006-01-01

    Different-sized aerosols were collected by an Andersen air sampler to observe the detailed morphology of the black carbon (BC) aerosols which were separated chemically from the other accompanying aerosols, using a Scanning Electron Microscope equipped with an Energy Dispersive X-ray Spectrometer (SEM-EDX). The results indicate that most BC aerosols are spherical particles of about 50 nm in diameter and with a homogeneous surface. Results also show that these particles aggregate with other aerosols or with themselves to form larger agglomerates in the micrometer range. The shape of these 50-nm BC spherical particles was found to be very similar to that of BC particles released from petroleum-powered vehicular internal combustion engines. These spherical BC particles were shown to be different from the previously reported fullerenes found using Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF-MS).

  4. Note: Design and development of wireless controlled aerosol sampling network for large scale aerosol dispersion experiments

    Energy Technology Data Exchange (ETDEWEB)

    Gopalakrishnan, V.; Subramanian, V.; Baskaran, R.; Venkatraman, B. [Radiation Impact Assessment Section, Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)

    2015-07-15

    Wireless based custom built aerosol sampling network is designed, developed, and implemented for environmental aerosol sampling. These aerosol sampling systems are used in field measurement campaign, in which sodium aerosol dispersion experiments have been conducted as a part of environmental impact studies related to sodium cooled fast reactor. The sampling network contains 40 aerosol sampling units and each contains custom built sampling head and the wireless control networking designed with Programmable System on Chip (PSoC™) and Xbee Pro RF modules. The base station control is designed using graphical programming language LabView. The sampling network is programmed to operate in a preset time and the running status of the samplers in the network is visualized from the base station. The system is developed in such a way that it can be used for any other environment sampling system deployed in wide area and uneven terrain where manual operation is difficult due to the requirement of simultaneous operation and status logging.

  5. Note: Design and development of wireless controlled aerosol sampling network for large scale aerosol dispersion experiments

    International Nuclear Information System (INIS)

    Wireless based custom built aerosol sampling network is designed, developed, and implemented for environmental aerosol sampling. These aerosol sampling systems are used in field measurement campaign, in which sodium aerosol dispersion experiments have been conducted as a part of environmental impact studies related to sodium cooled fast reactor. The sampling network contains 40 aerosol sampling units and each contains custom built sampling head and the wireless control networking designed with Programmable System on Chip (PSoC™) and Xbee Pro RF modules. The base station control is designed using graphical programming language LabView. The sampling network is programmed to operate in a preset time and the running status of the samplers in the network is visualized from the base station. The system is developed in such a way that it can be used for any other environment sampling system deployed in wide area and uneven terrain where manual operation is difficult due to the requirement of simultaneous operation and status logging

  6. Waste prevention action nets

    OpenAIRE

    Corvellec, Hervé; Czarniawska, Barbara

    2013-01-01

    Although waste prevention is considered the best possible waste management option in the European waste hierarchy model, it is unclear what constitutes waste prevention. To address this lack of clarity, this text presents an analysis of four Swedish case studies of waste prevention: a waste management company selling waste prevention services; the possibility offered to Swedish households to opt out of receiving unaddressed promotional material; a car-sharing program; and a re-...

  7. Solid waste management

    OpenAIRE

    Srebrenkoska, Vineta; Golomeova, Saska; Krsteva, Silvana

    2013-01-01

    Waste is unwanted or useless materials from households, industry, agriculture, hospitals. Waste materials in solid state are classified as solid waste. Increasing of the amount of solid waste and the pressure what it has on the environment, impose the need to introduce sustainable solid waste management. Advanced sustainable solid waste management involves several activities at a higher level of final disposal of the waste management hierarchy. Minimal use of material and energy resources ...

  8. Nuclear waste

    International Nuclear Information System (INIS)

    DOE estimates that disposing of radioactive waste from civilian nuclear power plants and its defense-related nuclear facilities could eventually end up costing $32 billion. To pay for this, DOE collects fees from utilities on electricity generated by nuclear power plants and makes payments from its defense appropriation. This report states that unless careful attention is given to its financial condition, the nuclear waste program is susceptible to future shortfalls. Without a fee increase, the civilian-waste part of the program may already be underfunded by at least $2.4 billion (in discounted 1988 dollars). Also, DOE has not paid its share of cost-about $480 million-nor has it disclosed this liability in its financial records. Indexing the civilian fee to the inflation rate would address one major cost uncertainty. However, while DOE intends to do this at an appropriate time, it does not use a realistic rate of inflation as its most probable scenario in assessing whether that time has arrived

  9. Nuclear waste

    International Nuclear Information System (INIS)

    The Department of Energy plans to award a contract to Bechtel Systems Management, Inc. to manage and operate the federal government's nuclear waste repository. The proposed management and operating contract is likely to substantially affect program operations and costs. This paper reports on a GAO report. A major concern is the degree to which the selected contractor might replace, or possibly duplicate, the efforts now being carried out by DOE's current contractors. It is questionable whether the contract will result in a more efficient and effective program. DOE officials have had to divert their attention from program operations to develop the contract proposal and participate in legal proceedings related to a bid protest. GAO and the DOE inspector general have reported on problems and issues involving DOE's administration of management and operating contracts, including some companies which participate in the nuclear waste program. Many of the resulting recommendations have yet to be implemented. Implementation of these recommendations could help ensure that the nuclear waste program is operated in a more cost-effective manner

  10. New satellite project Aerosol-UA: Remote sensing of aerosols in the terrestrial atmosphere

    Science.gov (United States)

    Milinevsky, G.; Yatskiv, Ya.; Degtyaryov, O.; Syniavskyi, I.; Mishchenko, M.; Rosenbush, V.; Ivanov, Yu.; Makarov, A.; Bovchaliuk, A.; Danylevsky, V.; Sosonkin, M.; Moskalov, S.; Bovchaliuk, V.; Lukenyuk, A.; Shymkiv, A.; Udodov, E.

    2016-06-01

    We discuss the development of the Ukrainian space project Aerosol-UA which has the following three main objectives: (1) to monitor the spatial distribution of key characteristics of terrestrial tropospheric and stratospheric aerosols; (2) to provide a comprehensive observational database enabling accurate quantitative estimates of the aerosol contribution to the energy budget of the climate system; and (3) quantify the contribution of anthropogenic aerosols to climate and ecological processes. The remote sensing concept of the project is based on precise orbital measurements of the intensity and polarization of sunlight scattered by the atmosphere and the surface with a scanning polarimeter accompanied by a wide-angle multispectral imager-polarimeter. Preparations have already been made for the development of the instrument suite for the Aerosol-UA project, in particular, of the multi-channel scanning polarimeter (ScanPol) designed for remote sensing studies of the global distribution of aerosol and cloud properties (such as particle size, morphology, and composition) in the terrestrial atmosphere by polarimetric and spectrophotometric measurements of the scattered sunlight in a wide range of wavelengths and viewing directions from which a scene location is observed. ScanPol is accompanied by multispectral wide-angle imager-polarimeter (MSIP) that serves to collect information on cloud conditions and Earth's surface image. Various components of the polarimeter ScanPol have been prototyped, including the opto-mechanical and electronic assemblies and the scanning mirror controller. Preliminary synthetic data simulations for the retrieval of aerosol parameters over land surfaces have been performed using the Generalized Retrieval of Aerosol and Surface Properties (GRASP) algorithm. Methods for the validation of satellite data using ground-based observations of aerosol properties are also discussed. We assume that designing, building, and launching into orbit a multi

  11. The contribution of aerosol hygroscopic growth to the modeled aerosol radiative effect

    Science.gov (United States)

    Kokkola, Harri; Kühn, Thomas; Kirkevåg, Alf; Romakkaniemi, Sami; Arola, Antti

    2016-04-01

    The hygroscopic growth of atmospheric aerosols can have a significant effect on the direct radiative effect of atmospheric aerosol. However, there are significant uncertainties concerning how much of the radiative forcing is due to different chemical compounds, especially water. For example, modeled optical depth of water in global aerosol-climate models varies by more than a factor of two. These differences can be attributed to differences in modeled 1) hygroscopicity, 2) ambient relative humidity, and/or 3) aerosol size distribution. In this study, we investigate which of these above-mentioned factors cause the largest variability in the modeled optical depth of water. In order to do this, we have developed a tool that calculates aerosol extinction using interchangeable global 3D data of aerosol composition, relative humidity, and aerosol size distribution fields. This data is obtained from models that have taken part in the open international initiative AeroCom (Aerosol Comparisons between Observations and Models). In addition, we use global 3D data for relative humidity from the Atmospheric Infrared Sounder (AIRS) flying on board NASA's Aqua satellite and the National Centers for Environmental Prediction (NCEP) reanalysis data. These observations are used to evaluate the modeled relative humidity fields. In the first stage of the study, we made a detailed investigation using the aerosol-chemistry-climate model ECHAM-HAMMOZ in which most of the aerosol optical depth is caused by water. Our results show that the model significantly overestimates the relative humidity over the oceans while over land, the overestimation is lower or it is underestimated. Since this overestimation occurs over the oceans, the water optical depth is amplified as the hygroscopic growth is very sensitive to changes in high relative humidities. Over land, error in modeled relative humidity is unlikely to cause significant errors in water optical depth as relative humidities are generally

  12. New Satellite Project Aerosol-UA: Remote Sensing of Aerosols in the Terrestrial Atmosphere

    Science.gov (United States)

    Milinevsky, G.; Yatskiv, Ya.; Degtyaryov, O.; Syniavskyi, I.; Mishchenko, Michael I.; Rosenbush, V.; Ivanov, Yu.; Makarov, A.; Bovchaliuk, A.; Danylevsky, V.; Sosonkin, M.; Moskalov, S.; Bovchaliuk, V; Lukenyuk, A.; Shymkiv, A.

    2016-01-01

    We discuss the development of the Ukrainian space project Aerosol-UA which has the following three main objectives: (1) to monitor the spatial distribution of key characteristics of terrestrial tropospheric and stratospheric aerosols; (2) to provide a comprehensive observational database enabling accurate quantitative estimates of the aerosol contribution to the energy budget of the climate system; and (3) quantify the contribution of anthropogenic aerosols to climate and ecological processes. The remote sensing concept of the project is based on precise orbital measurements of the intensity and polarization of sunlight scattered by the atmosphere and the surface with a scanning polarimeter accompanied by a wide-angle multispectral imager-polarimeter. Preparations have already been made for the development of the instrument suite for the Aerosol-UA project, in particular, of the multi-channel scanning polarimeter (ScanPol) designed for remote sensing studies of the global distribution of aerosol and cloud properties (such as particle size, morphology, and composition) in the terrestrial atmosphere by polarimetric and spectrophotometric measurements of the scattered sunlight in a wide range of wavelengths and viewing directions from which a scene location is observed. ScanPol is accompanied by multispectral wide-angle imager-polarimeter (MSIP) that serves to collect information on cloud conditions and Earths surface image. Various components of the polarimeter ScanPol have been prototyped, including the opto-mechanical and electronic assemblies and the scanning mirror controller. Preliminary synthetic data simulations for the retrieval of aerosol parameters over land surfaces have been performed using the Generalized Retrieval of Aerosol and Surface Properties (GRASP) algorithm. Methods for the validation of satellite data using ground-based observations of aerosol properties are also discussed. We assume that designing, building, and launching into orbit a multi

  13. Modeling the Relationships Between Aerosol Properties and the Direct and Indirect Effects of Aerosols on Climate

    Science.gov (United States)

    Toon, Owen B.

    1994-01-01

    Aerosols may affect climate directly by scattering and absorbing visible and infrared energy, They may also affect climate indirectly by modifying the properties of clouds through microphysical processes, and by altering abundances of radiatively important gases through heterogeneous chemistry. Researchers understand which aerosol properties control the direct effect of aerosols on the radiation budget. Unfortunately, despite an abundance of data on certain types of aerosols, much work remains to be done to determine the values of these properties. For instance we have little idea about the global distribution, seasonal variation, or interannual variability of the aerosol optical depth. Also we do not know the visible light absorption properties of tropical aerosols which may contain much debris from slash and burn agriculture. A positive correlation between aerosol concentrations and albedos of marine stratus clouds is observed, and the causative microphysics is understood. However, models suggest that it is difficult to produce new particles in the marine boundary layer. Some modelers have suggested that the particles in the marine boundary layer may originate in the free troposphere and be transported into the boundary layer. Others argue that the aerosols are created in the marine boundary layer. There are no data linking aerosol concentration and cirrus cloud albedo, and models suggest cirrus properties may not be very sensitive to aerosol abundance. There is clear evidence of a radiatively significant change in the global lower stratospheric ozone abundance during the past few decades. These changes are caused by heterogeneous chemical reactions occurring on the surfaces of particles. The rates of these reactions depend upon the chemical composition of the particles. Although rapid advances in understanding heterogeneous chemistry have been made, much remains to be done.

  14. Development of a cavity enhanced aerosol albedometer

    Directory of Open Access Journals (Sweden)

    W. Zhao

    2014-03-01

    Full Text Available We report on the development of a cavity enhanced aerosol single scattering albedometer incorporating incoherent broad-band cavity-enhanced spectroscopy (IBBCEAS approach and an integrating sphere (IS for simultaneous in situ measurements of aerosol scattering and extinction coefficients in the exact same sample volume. The cavity enhanced albedometer employed a blue light-emitting diode (LED based IBBCEAS approach for the measurement of wavelength-resolved aerosol optical extinction over the spectral range of 445–480 nm. An integrating sphere nephelometer coupled to the IBBCEAS setup was used for the measurement of aerosol scattering. The scattering signal was measured with a single channel photomultiplier tube (PMT, providing an integrated value over a narrow bandwidth (FWHM ~ 9 nm in the spectral region of 465–474 nm. A scattering coefficient at a wavelength of 470 nm was deduced as an averaged scattering value and used for data analysis and instrumental performance comparison. Performance evaluation of the albedometer was carried out using laboratory-generated particles and ambient aerosol. The scattering and extinction measurements of monodisperse polystyrene latex (PSL spheres generated in laboratory proved excellent correlation between two channels of the albedometer. The retrieved refractive index (RI from the measured scattering and extinction efficiencies agreed well with the values reported in previously published papers. Aerosol light scattering and extinction coefficients, single scattering albedo (SSA and NO2 concentrations in an ambient sample were directly and simultaneously measured using the developed albedometer. The developed instrument was validated via an intercomparison of the measured aerosol scattering coefficient and NO2 trace concentration against a TSI 3563 integrating nephelometer and a chemiluminescence detector, respectively.

  15. Beijing aerosol: Atmospheric interactions and new trends

    International Nuclear Information System (INIS)

    Beijing aerosols are scrutinized as a case study for atmospheric interactions in a complex multi-source situation. For the first time, fine (≤ 2 μm) and coarse (≥ 2 μm) aerosols were continuously collected during a time period (20 months) long enough to capture seasonal trends of sources and interactions. Weekly samples were obtained from January 2003 to August 2004 downtown and during 9 months at two peri-urban sites. Aerosol samples were chemically characterized (black carbon (BC), organic carbon (OC), and major ions) and dust was obtained from mass closure. Concentration data were smoothed and boundary layer height (BLH) corrected in order to better identify sources and processes. All yearlong, the coarse aerosol is dominated by dust (75%) whereas the fine mode is dominated (46%) by carbonaceous particles. Photochemistry is an intense driving force for secondary aerosol formation including secondary organic aerosol (SOA). Dust particles present a reactive surface for secondary aerosol formation from the intense anthropogenic pool of acidic gaseous precursors (SO2, HNO3, and volatile organic compounds (VOCs)). These interactions favor the formation of a very significant coarse fraction for SO4, NO3, and POM, a feature almost never encountered in developed countries. Surprisingly too is the presence of fine NH4NO3 in summer. A new result is also that the winter 'heating season' appears at present of minor importance with, however, a significant component from domestic heating as traced by BC/OC. In the future, traffic is likely to dominate downtown anthropogenic emissions. Year-to-year variability in meteorological conditions is likely to influence inputs from arid regions and from regional industrial and biomass burning sources. (authors)

  16. Waste management and security

    International Nuclear Information System (INIS)

    Full text: Waste Management (WM) has become an applied science. It is used at the point of generation, at the centralized treatment facilities, and at the disposal sites. In the government and private sector, much research is being done in waste by-product utilization. Some of the important factors that affect waste are sources of waste, classification of waste, waste treatment and conditioning, minimization of waste, laws and regulations governing waste and present and future issues. WM has become a career with a promising future as the cost of waste disposal increases tremendously. Scientists have started working on waste minimization and most organizations implement a formalized waste minimization program of their own. The waste disposal is approached in an analytical manner and this paper describes development in radioactive waste disposal and safe transportation practices

  17. Rethinking the waste hierarchy

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, C.; Vigsoe, D. (eds.)

    2005-03-01

    There is an increasing need to couple environmental and economic considerations within waste management. Consumers and companies alike generate ever more waste. The waste-policy challenges of the future lie in decoupling growth in waste generation from growth in consumption, and in setting priorities for the waste management. This report discusses the criteria for deciding priorities for waste management methods, and questions the current principles of EU waste policies. The basis for the discussion is the so-called waste hierarchy which has dominated the waste policy in the EU since the mid-1970s. The waste hierarchy ranks possible methods of waste management. According to the waste hierarchy, the very best solution is to reduce the amount of waste. After that, reuse is preferred to recycling which, in turn, is preferred to incineration. Disposal at a landfill is the least favourable solution. (BA)

  18. Disposal of hazardous wastes

    International Nuclear Information System (INIS)

    The Fifth Life Sciences Symposium entitled Hazardous Solid Wastes and Their Disposal on October 12 through 14, 1977 was summarized. The topic was the passage of the National Resources Conservation and Recovery Act of 1976 will force some type of action on all hazardous solid wastes. Some major points covered were: the formulation of a definition of a hazardous solid waste, assessment of long-term risk, list of specific materials or general criteria to specify the wastes of concern, Bioethics, sources of hazardous waste, industrial and agricultural wastes, coal wastes, radioactive wastes, and disposal of wastes

  19. Household hazardous waste

    DEFF Research Database (Denmark)

    Fjelsted, Lotte; Christensen, Thomas Højlund

    2007-01-01

    .) comprised 15-25% and foreign items comprised 10-20%. Water-based paint was the dominant part of the paint waste. The chemical composition of the paint waste and the paint-like waste was characterized by an analysis of 27 substances in seven waste fractions. The content of critical substances was tow and the...... incinerated. Allowing household paint waste to be collected with ordinary household waste is expected to reduce the cost of handling household hazardous waste, since paint waste in Denmark comprises the major fraction of household hazardous waste....

  20. Other Special Waste

    DEFF Research Database (Denmark)

    Brogaard, Line Kai-Sørensen; Christensen, Thomas Højlund

    2011-01-01

    In addition to the main types of special waste related to municipal solid waste (MSW) mentioned in the previous chapters (health care risk waste, WEEE, impregnated wood, hazardous waste) a range of other fractions of waste have in some countries been defined as special waste that must be handled...... separately from MSW. Some of these other special wastes are briefly described in this chapter with respect to their definition, quantity and composition, and management options. The special wastes mentioned here are batteries, tires, polyvinylchloride (PVC) and food waste....

  1. Retrieving aerosol in a cloudy environment: aerosol product availability as a function of spatial resolution

    Directory of Open Access Journals (Sweden)

    L. A. Remer

    2012-07-01

    Full Text Available The challenge of using satellite observations to retrieve aerosol properties in a cloudy environment is to prevent contamination of the aerosol signal from clouds, while maintaining sufficient aerosol product yield to satisfy specific applications. We investigate aerosol retrieval availability at different instrument pixel resolutions using the standard MODIS aerosol cloud mask applied to MODIS data and supplemented with a new GOES-R cloud mask applied to GOES data for a domain covering North America and surrounding oceans. Aerosol product availability is not the same as the cloud free fraction and takes into account the techniques used in the MODIS algorithm to avoid clouds, reduce noise and maintain sufficient numbers of aerosol retrievals. The inherent spatial resolution of each instrument, 0.5×0.5 km for MODIS and 1×1 km for GOES, is systematically degraded to 1×1, 2×2, 1×4, 4×4 and 8×8 km resolutions and then analyzed as to how that degradation would affect the availability of an aerosol retrieval, assuming an aerosol product resolution at 8×8 km. The analysis is repeated, separately, for near-nadir pixels and those at larger view angles to investigate the effect of pixel growth at oblique angles on aerosol retrieval availability. The results show that as nominal pixel size increases, availability decreases until at 8×8 km 70% to 85% of the retrievals available at 0.5 km, nadir, have been lost. The effect at oblique angles is to further decrease availability over land but increase availability over ocean, because sun glint is found at near-nadir view angles. Finer resolution sensors (i.e., 1×1, 2×2 or even 1×4 km will retrieve aerosols in partly cloudy scenes significantly more often than sensors with nadir views of 4×4 km or coarser. Large differences in the results of the two cloud masks designed for MODIS aerosol and GOES cloud products strongly reinforce that cloud masks must be developed with specific purposes in mind and

  2. Aromatic Structure in Simulates Titan Aerosol

    Science.gov (United States)

    Trainer, Melissa G.; Loeffler, M. J.; Anderson, C. M.; Hudson, R. L.; Samuelson, R. E.; Moore, M. A.

    2011-01-01

    Observations of Titan by the Cassini Composite Infrared Spectrometer (CIRS) between 560 and 20 per centimeter (approximately 18 to 500 micrometers) have been used to infer the vertical variations of Titan's ice abundances, as well as those of the aerosol from the surface to an altitude of 300 km [1]. The aerosol has a broad emission feature centered approximately at 140 per centimeter (71 micrometers). As seen in Figure 1, this feature cannot be reproduced using currently available optical constants from laboratory-generated Titan aerosol analogs [2]. The far-IR is uniquely qualified for investigating low-energy vibrational motions within the lattice structures of COITIDlex aerosol. The feature observed by CIRS is broad, and does not likely arise from individual molecules, but rather is representative of the skeletal movements of macromolecules. Since Cassini's arrival at Titan, benzene (C6H6) has been detected in the atmosphere at ppm levels as well as ions that may be polycyclic aromatic hydrocarbons (PAHs) [3]. We speculate that the feature may be a blended composite that can be identified with low-energy vibrations of two-dimensional lattice structures of large molecules, such as PAHs or nitrogenated aromatics. Such structures do not dominate the composition of analog materials generated from CH4 and N2 irradiation. We are performing studies forming aerosol analog via UV irradiation of aromatic precursors - specifically C6H6 - to understand how the unique chemical architecture of the products will influence the observable aerosol characteristics. The optical and chemical properties of the aromatic analog will be compared to those formed from CH4/N2 mixtures, with a focus on the as-yet unidentified far-IR absorbance feature. Preliminary results indicate that the photochemically-formed aromatic aerosol has distinct chemical composition, and may incorporate nitrogen either into the ring structure or adjoined chemical groups. These compositional differences are

  3. Intercomparison of aerosol instruments: number concentration

    International Nuclear Information System (INIS)

    An intercomparison of aerosol instruments conducted February 23-27, 1981, at the Environmental Measurements Laboratory (EML) focused on five instruments: the Pollak and TSI condensation nucleus counters; the Active Scattering Aerosol Spectrometer (ASAS-X); and two aerosol electrometers. Test aerosols of sodium chloride and ammonium fluorescein generated by nebulization/electrostatic classification were used to obtain 195 lines of comparison data. Concentrations measured by the ASAS-X and the TSI aerosol electrometer averaged respectively 1.388 and 1.581 times that measured by the Pollak. These ratios were very stable during the week and there was little effect of particle size or material. Most other comparisons were equally stable. However, a review of past work at EML and elsewhere led to the disturbing conclusion that these ratios may change from year to year, or from season to season. A filter sample was taken from microscopy, concurrent with readings from the ASAS-X and the TSI condensation nucleus counters. In this sample, the two instruments differed by 20%. Within its 20% uncertainty, the filter result matched both the TSI and ASAS-X readings

  4. Microphysical Characterization of Aerosol Signatures over Greece

    Directory of Open Access Journals (Sweden)

    Akshath Sharma

    2016-07-01

    Full Text Available A detailed microphysical characterization is presented for aerosol spectra over three major areas over Greece, namely- the Area West of Crete (AWC, the Greater Thessaloniki area (GTA and the Greater Athens Area (GAA based on measurements made by Varotsos (2005. Aerosol size distributions along with cloud droplet concentrations were gathered from data collected from the Forward Scattering Spectrometer Probe (FSSP-300 and Passive Cavity Aerosol Spectrometer Probe (PCASP-100X flown on a Falcon aircraft over Greece (Varotsos, 2005. However, the microphysical and dynamical characterisation of the observations were left largely unexplored (for this later paper, particularly with regard to their growth and activation into cloud condensation nuclei. A suite of models involving Large Eddy Simulations and an Adiabatic Parcel Model were used to achieve this. The UK Met Office large eddy model (LEM reveals that mild to moderate updraughts in the range of 0.5 ms-1 to 2 ms-1 were present over Athens during June 1997, over the regions containing the aerosol bands. The sophisticated parcel model was then been applied to this data to study the growth of aerosol in the updraughts present and further, to explore the possibility of rainfall. It is found that the grown droplets have radii spanning a range of 6 μm to 100 μm indicating a hundredfold increase over initial size and the region spanning height from 2700 to 3000 meters contains precipitable water.

  5. Monitoring biological aerosols using UV fluorescence

    Science.gov (United States)

    Eversole, Jay D.; Roselle, Dominick; Seaver, Mark E.

    1999-01-01

    An apparatus has been designed and constructed to continuously monitor the number density, size, and fluorescent emission of ambient aerosol particles. The application of fluorescence to biological particles suspended in the atmosphere requires laser excitation in the UV spectral region. In this study, a Nd:YAG laser is quadrupled to provide a 266 nm wavelength to excite emission from single micrometer-sized particles in air. Fluorescent emission is used to continuously identify aerosol particles of biological origin. For calibration, biological samples of Bacillus subtilis spores and vegetative cells, Esherichia coli, Bacillus thuringiensis and Erwinia herbicola vegetative cells were prepared as suspensions in water and nebulized to produce aerosols. Detection of single aerosol particles, provides elastic scattering response as well as fluorescent emission in two spectral bands simultaneously. Our efforts have focuses on empirical characterization of the emission and scattering characteristics of various bacterial samples to determine the feasibility of optical discrimination between different cell types. Preliminary spectroscopic evidence suggest that different samples can be distinguished as separate bio-aerosol groups. In addition to controlled sample results, we will also discuss the most recent result on the effectiveness of detection outdoor releases and variations in environmental backgrounds.

  6. Spectral Absorption Properties of Atmospheric Aerosols

    Science.gov (United States)

    Bergstrom, R. W.; Pilewskie, P.; Russell, P. B.; Redemann, J.; Bond, T. C.; Quinn, P. K.; Sierau, B.

    2007-01-01

    We have determined the solar spectral absorption optical depth of atmospheric aerosols for specific case studies during several field programs (three cases have been reported previously; two are new results). We combined airborne measurements of the solar net radiant flux density and the aerosol optical depth with a detailed radiative transfer model for all but one of the cases. The field programs (SAFARI 2000, ACE Asia, PRIDE, TARFOX, INTEX-A) contained aerosols representing the major absorbing aerosol types: pollution, biomass burning, desert dust and mixtures. In all cases the spectral absorption optical depth decreases with wavelength and can be approximated with a power-law wavelength dependence (Absorption Angstrom Exponent or AAE). We compare our results with other recent spectral absorption measurements and attempt to briefly summarize the state of knowledge of aerosol absorption spectra in the atmosphere. We discuss the limitations in using the AAE for calculating the solar absorption. We also discuss the resulting spectral single scattering albedo for these cases.

  7. Hanford Site annual dangerous waste report: Volume 1, Part 1, Generator dangerous waste report, dangerous waste

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    This report contains information on hazardous wastes at the Hanford Site. Information consists of shipment date, physical state, chemical nature, waste description, waste number, weight, and waste designation.

  8. Hanford Site annual dangerous waste report: Volume 1, Part 1, Generator dangerous waste report, dangerous waste

    International Nuclear Information System (INIS)

    This report contains information on hazardous wastes at the Hanford Site. Information consists of shipment date, physical state, chemical nature, waste description, waste number, weight, and waste designation

  9. Atmospheric Aerosol Analysis using Lightweight Mini GC Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The major components of manmade aerosols are created by the burning of coal and oil. These aerosols are recognized to have a significant climatic impact through...

  10. MISR Level 2 FIRSTLOOK Aerosol parameters V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This is the Level 2 FIRSTLOOK Aerosol Product. It contains Aerosol optical depth and particle type, with associated atmospheric data, produced using ancillary...

  11. Volatility of Nuclei Mode Arctic Aerosol Particles during Summer

    Czech Academy of Sciences Publication Activity Database

    Biskos, J.G.; Vratolis, S.; Ondráček, Jakub; Karanasioy, A.A.; Eleftheriadis, K.

    -: -, 2009, T160A13. [European Aerosol Conference 2009. Karlsruhe (DE), 06.09.2009-11.09.2009] Institutional research plan: CEZ:AV0Z40720504 Keywords : arctic aerosol * nucleation mode * volatility Subject RIV: CF - Physical ; Theoretical Chemistry

  12. VERTICAL DISTRIBUTION OF ATMOSPHERIC AEROSOL CONCENTRATION AT XIANGHE

    Institute of Scientific and Technical Information of China (English)

    Li Xu; Guangyu Shi; Jun Zhou; Yasunobu Iwasaka

    2004-01-01

    This paper summarizes atmospheric aerosol concentrations of 5 stratospheric balloon soundings during the period from 1984 to 1994. Aerosol-rich layers in the troposphere were detected and the causes were analyzed. The main results are as follows: (1) the vertical distribution of the atmospheric aerosol is affected by atmospheric dynamic processes, humidity, etc.; (2) the tropospheric column concentrations of aerosol were 72.2×105, 20.2×105, 20.7×105 and 34.4×105 cm-2 and occupying 81%, 61% and 60% of the 0-to-30 km aerosol column, on Aug. 23, 1984, Aug. 22, 1993,Sept. 12, 1993 and Sept. 15, 1994, respectively; (3) the effect of volcano eruption was still evident in the aerosol profiles,28 and 27 months after the El Chichon and Pinatubo eruption; (4) the aerosol concentration in the troposphere did not decrease at all heights as atmospheric aerosol model.

  13. MISR Level 3 Global Joint Aerosol monthly product V001

    Data.gov (United States)

    National Aeronautics and Space Administration — MISR Level 3 Global Joint Aerosol monthly product (Suggested Usage: This file contains MISR Level 3 Global Joint Aerosol monthly product, binned at 5 degree...

  14. Characterisation of high dose aerosols from dry powder inhalers

    NARCIS (Netherlands)

    Grasmeijer, Floris; Hagedoorn, Paul; Frijlink, Henderik W; de Boer, Anne H

    2012-01-01

    Developments in high dose dry powder aerosol delivery will increasingly challenge the applicability of currently used aerosol characterisation techniques. With cascade impaction analysis bounce effects can negatively influence stage collection efficiency, especially with increasing impactor loads. I

  15. Atmospheric Aerosol Analysis using Lightweight Mini GC Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The major components of manmade aerosols are created by the burning of coal and oil. Aerosols are recognized to significantly impact the climate through their...

  16. A characterization of Arctic aerosols on the basis of aerosol optical depth and black carbon measurements

    Directory of Open Access Journals (Sweden)

    R. S. Stone

    2014-06-01

    Full Text Available Abstract Aerosols, transported from distant source regions, influence the Arctic surface radiation budget. When deposited on snow and ice, carbonaceous particles can reduce the surface albedo, which accelerates melting, leading to a temperature-albedo feedback that amplifies Arctic warming. Black carbon (BC, in particular, has been implicated as a major warming agent at high latitudes. BC and co-emitted aerosols in the atmosphere, however, attenuate sunlight and radiatively cool the surface. Warming by soot deposition and cooling by atmospheric aerosols are referred to as “darkening” and “dimming” effects, respectively. In this study, climatologies of spectral aerosol optical depth AOD (2001–2011 and Equivalent BC (EBC (1989–2011 from three Arctic observatories and from a number of aircraft campaigns are used to characterize Arctic aerosols. Since the 1980s, concentrations of BC in the Arctic have decreased by more than 50% at ground stations where in situ observations are made. AOD has increased slightly during the past decade, with variations attributed to changing emission inventories and source strengths of natural aerosols, including biomass smoke and volcanic aerosol, further influenced by deposition rates and airflow patterns.

  17. Multicomponent aerosol dynamics model UHMA: model development and validation

    OpenAIRE

    Korhonen, H.; Lehtinen, K. E. J.; Kulmala, M.

    2004-01-01

    A size-segregated aerosol dynamics model UHMA (University of Helsinki Multicomponent Aerosol model) was developed for studies of multicomponent tropospheric aerosol particles. The model includes major aerosol microphysical processes in the atmosphere with a focus on new particle formation and growth; thus it incorporates particle coagulation and multicomponent condensation, applying a revised treatment of condensation flux onto free molecular regime particles and the activation of nanosi...

  18. Effect of Aerosol and Ocean Representation on Simulated Climate Responses

    Science.gov (United States)

    Dallafior, Tanja; Folini, Doris; Knutti, Reto; Wild, Martin

    2016-04-01

    It is still debated to what extent anthropogenic aerosols shaped 20th century surface temperatures, especially sea surface temperatures (SSTs), through alteration of surface solar radiation (SSR). SSTs, in turn, are crucial in the context of atmospheric circulation and ocean heat uptake. Uncertainty considering anthropogenic aerosol forcing thus translates into uncertainty regarding ocean heat uptake and, ultimately, climate responses towards anthropogenic influences. We use the global climate model ECHAM to analyse the 20th century climate response towards either anthropogenic aerosols or well-mixed greenhouse gases or both with different representations of ocean and aerosols: atmosphere-only with prescribed SSTs and interactive aerosols; mixed-layer ocean and interactive or prescribed aerosols; fully coupled with prescribed aerosols. For interactive aerosols we use the Hamburg Aerosol Module (HAM). Our results suggest that up to 15% of global ocean surfaces undergo an SSR reduction of at least -4W/m² in the year 2000, due to anthropogenic aerosols. The area affected depends on how aerosols are represented and whether clear sky or all sky SSR is considered. In MLO equilibria with interactive aerosols, anthropogenic aerosols clearly shape surface temperature response patterns. This is to a lesser degree the case for the transient fully coupled case. Additivity of global mean temperature responses towards single forcings - an assumption often made in the literature - is not fulfilled for the MLO experiments, but for the fully coupled experiments. While some of these differences can be attributed to the differing ocean representation, it is implied that differing aerosol representation may play an even more relevant role. Thus, our results corroborate not only the relevance of anthropogenic aerosols for surface temperature responses, but also highlight the relevance of choice of aerosol representation.

  19. Global modeling of organic aerosol: the importance of reactive nitrogen

    OpenAIRE

    H. O. T. Pye; A. W. H. Chan; Barkley, M. P.; Seinfeld, J. H.

    2010-01-01

    Reactive nitrogen compounds, specifically NOx and NO3, likely influence global organic aerosol levels. To assess these interactions, GEOS-Chem, a chemical transport model, is updated to include improved biogenic emissions (following MEGAN v2.1/2.04), a new organic aerosol tracer lumping scheme, aerosol from nitrate radical (NO3) oxidation of isoprene, and NOx-dependent terpene aerosol yields. As a resu...

  20. Waste remediation

    Science.gov (United States)

    Halas, Nancy J.; Nordlander, Peter; Neumann, Oara

    2015-12-29

    A system including a steam generation system and a chamber. The steam generation system includes a complex and the steam generation system is configured to receive water, concentrate electromagnetic (EM) radiation received from an EM radiation source, apply the EM radiation to the complex, where the complex absorbs the EM radiation to generate heat, and transform, using the heat generated by the complex, the water to steam. The chamber is configured to receive the steam and an object, wherein the object is of medical waste, medical equipment, fabric, and fecal matter.

  1. Central Waste Complex (CWC) Waste Analysis Plan

    International Nuclear Information System (INIS)

    The purpose of this waste analysis plan (WAP) is to document the waste acceptance process, sampling methodologies, analytical techniques, and overall processes that are undertaken for waste accepted for storage at the Central Waste Complex (CWC), which is located in the 200 West Area of the Hanford Facility, Richland, Washington. Because dangerous waste does not include the source, special nuclear, and by-product material components of mixed waste, radionuclides are not within the scope of this documentation. The information on radionuclides is provided only for general knowledge

  2. Whole-Body Nanoparticle Aerosol Inhalation Exposures

    Science.gov (United States)

    Yi, Jinghai; Chen, Bean T.; Schwegler-Berry, Diane; Frazer, Dave; Castranova, Vince; McBride, Carroll; Knuckles, Travis L.; Stapleton, Phoebe A.; Minarchick, Valerie C.; Nurkiewicz, Timothy R.

    2013-01-01

    Inhalation is the most likely exposure route for individuals working with aerosolizable engineered nano-materials (ENM). To properly perform nanoparticle inhalation toxicology studies, the aerosols in a chamber housing the experimental animals must have: 1) a steady concentration maintained at a desired level for the entire exposure period; 2) a homogenous composition free of contaminants; and 3) a stable size distribution with a geometric mean diameter < 200 nm and a geometric standard deviation σg < 2.5 5. The generation of aerosols containing nanoparticles is quite challenging because nanoparticles easily agglomerate. This is largely due to very strong inter-particle forces and the formation of large fractal structures in tens or hundreds of microns in size 6, which are difficult to be broken up. Several common aerosol generators, including nebulizers, fluidized beds, Venturi aspirators and the Wright dust feed, were tested; however, none were able to produce nanoparticle aerosols which satisfy all criteria 5. A whole-body nanoparticle aerosol inhalation exposure system was fabricated, validated and utilized for nano-TiO2 inhalation toxicology studies. Critical components: 1) novel nano-TiO2 aerosol generator; 2) 0.5 m3 whole-body inhalation exposure chamber; and 3) monitor and control system. Nano-TiO2 aerosols generated from bulk dry nano-TiO2 powders (primary diameter of 21 nm, bulk density of 3.8 g/cm3) were delivered into the exposure chamber at a flow rate of 90 LPM (10.8 air changes/hr). Particle size distribution and mass concentration profiles were measured continuously with a scanning mobility particle sizer (SMPS), and an electric low pressure impactor (ELPI). The aerosol mass concentration (C) was verified gravimetrically (mg/m3). The mass (M) of the collected particles was determined as M = (Mpost-Mpre), where Mpreand Mpost are masses of the filter before and after sampling (mg). The mass concentration was calculated as C = M/(Q*t), where Q is

  3. Phase transformation and growth of hygroscopic aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Tang, I.N.

    1999-11-01

    Ambient aerosols play an important role in many atmospheric processes affecting air quality, visibility degradation, and climatic changes as well. Both natural and anthropogenic sources contribute to the formation of ambient aerosols, which are composed mostly of sulfates, nitrates, and chlorides in either pure or mixed forms. These inorganic salt aerosols are hygroscopic by nature and exhibit the properties of deliquescence and efflorescence in humid air. For pure inorganic salt particles with diameter larger than 0.1 micron, the phase transformation from a solid particle to a saline droplet occurs only when the relative humidity in the surrounding atmosphere reaches a certain critical level corresponding to the water activity of the saturated solution. The droplet size or mass in equilibrium with relative humidity can be calculated in a straightforward manner from thermodynamic considerations. For aqueous droplets 0.1 micron or smaller, the surface curvature effect on vapor pressure becomes important and the Kelvin equation must be used.

  4. Washout and dry deposition of atmospheric aerosols

    International Nuclear Information System (INIS)

    The deposition velocities onto different rough surfaces and the washout coefficients of simulated rain droplets for submicron aerosols were studied in a wind channel. The influence of particle size and electric charge upon the collection efficiencies of simulated rain droplets was measured. The deposition velocity of the particles was determined as a function of aerosol size, wind velocity and roughness of the surface. The experiments were carried out with monodisperse, radioactive particles with sizes which were varied from 0.03 and 5 μm. Using the measured values, the activity flux of the long lived radon decay product (RaD), the mass flux of the atmospheric aerosol and the activity flux near a stack of a nuclear power plant onto the ground surface were calculated considering washout, rainout and dry deposition in the atmosphere. (author)

  5. Accelerator based techniques for aerosol analysis

    International Nuclear Information System (INIS)

    At the 3 MV Tandetron accelerator of the LABEC laboratory of INFN (Florence, Italy) an external beam facility is fully dedicated to PIXE-PIGE measurements of elemental composition of atmospheric aerosols. Examples regarding recent monitoring campaigns, performed in urban and remote areas, both on a daily basis and with high time resolution, as well as with size selection, will be presented. It will be evidenced how PIXE can provide unique information in aerosol studies or can play a complementary role to traditional chemical analysis. Finally a short presentation of 14C analysis of the atmospheric aerosol by Accelerator Mass Spectrometry (AMS) for the evaluation of the contributions from either fossil fuel combustion or modern sources (wood burning, biogenic activity) will be given. (author)

  6. Change in global aerosol composition since preindustrial times

    NARCIS (Netherlands)

    Tsigaridis, K.; Krol, M.C.; Dentener, F.; Balkanski, Y.; Lathiere, J.; Metzger, S.; Hauglustaine, D.; Kanakidou, M.

    2006-01-01

    To elucidate human induced changes of aerosol load and composition in the atmosphere, a coupled aerosol and gas-phase chemistry transport model of the troposphere and lower stratosphere has been used. The present 3-D modeling study focuses on aerosol chemical composition change since preindustrial t

  7. Aerosol retrieval from OMI: Applications to the amazon bassin

    NARCIS (Netherlands)

    Curier, R.L.; Veefkind, J.P.; Veilhmann, B.; Braak, R.; Torres, O.; Leeuw, G.de

    2007-01-01

    We present the aerosol optical depth retrieved from OMI measurements using the multi-wavelengthm algorithm for two different environments: over Western Europe where the aerosols are weakly absorbing and over the Amazon basin where aerosol optical properties are governed by biomass burning. The resul

  8. Improvements in the Advanced Navy Aerosol Model (ANAM)

    NARCIS (Netherlands)

    Eijk, A.M.J. van; Merritt, D.L.

    2006-01-01

    The Navy Aerosol Model (NAM) is widely used as an engineering tool to provide a quick estimate of the aerosol extinction in the marine environment. Since its introduction, several shortcomings of NAM have been identified that are being addressed by the development of the Advanced Navy Aerosol Model

  9. Determination of atmospheric aerosol properties over land using satellite measurements

    NARCIS (Netherlands)

    Kokhanovsky, A.A.; Leeuw, G. de

    2009-01-01

    Mostly, aerosol properties are poorly understood because the aerosol properties are very sparse. The first workshop on the determination of atmospheric aerosol properties over land using satellite measurements is convened in Bremen, Germany. In this workshop, the topics of discussions included a var

  10. METHODS OF CALCULATINAG LUNG DELIVERY AND DEPOSITION OF AEROSOL PARTICLES

    Science.gov (United States)

    Lung deposition of aerosol is measured by a variety of methods. Total lung deposition can be measured by monitoring inhaled and exhaled aerosols in situ by laser photometry or by collecting the aerosols on filters. The measurements can be performed accurately for stable monod...

  11. THE EFFECT OF AEROSOLIZATION ON SUBSEQUENT BACTERIAL SURVIVAL

    Science.gov (United States)

    To determine whether aerosolization could impair baterial survival, Pseudomonas syringae and Erwinia herbicola were aerosolized in a greenhouse, the aerosol was sampled at various distances from the site of release by using all-glass impingers, and bacterial survival was followed...

  12. Size Dependence of Incorporation of Gas Molecules into Aerosol Nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Levdansky, V.V.; Smolík, Jiří; Ždímal, Vladimír; Moravec, Pavel

    Prague : Czech Aerosol Society , 2013, C027. ISBN N. [European Aerosol Conference (EAC 2013). Prague (CZ), 01.09.2013-06.09.2013] R&D Projects: GA AV ČR IAA200760905 Institutional support: RVO:67985858 Keywords : aerosol * nanoparticles * size effect Subject RIV: CF - Physical ; Theoretical Chemistry http://eac2013.cz/index.php

  13. Global modeling of organic aerosol: the importance of reactive nitrogen

    Science.gov (United States)

    Pye, H. O. T.; Chan, A. W. H.; Barkley, M. P.; Seinfeld, J. H.

    2010-09-01

    Reactive nitrogen compounds, specifically NOx and NO3, likely influence global organic aerosol levels. To assess these interactions, GEOS-Chem, a chemical transport model, is updated to include improved biogenic emissions (following MEGAN v2.1/2.04), a new organic aerosol tracer lumping scheme, aerosol from nitrate radical (NO3) oxidation of isoprene, and NOx-dependent terpene aerosol yields. As a result of significant nighttime terpene emissions, fast reaction of monoterpenes with the nitrate radical, and relatively high aerosol yields from NO3 oxidation, biogenic hydrocarbon-NO3 reactions are expected to be a major contributor to surface level aerosol concentrations in anthropogenically influenced areas such as the United States. By including aerosol from nitrate radical oxidation in GEOS-Chem, terpene aerosol approximately doubles and isoprene aerosol is enhanced by 30 to 40% in the Southeast United States. In terms of the global budget of organic aerosol, however, aerosol from nitrate radical oxidation is somewhat minor (slightly more than 3 Tg/yr) due to the relatively high volatility of organic-NO3 oxidation products. Globally, 69 to 88 Tg/yr of organic aerosol is predicted to be produced annually, of which 14-15 Tg/yr is from oxidation of monoterpenes and sesquiterpenes and 8-9 Tg/yr from isoprene.

  14. Global modeling of organic aerosol: the importance of reactive nitrogen

    Directory of Open Access Journals (Sweden)

    H. O. T. Pye

    2010-09-01

    Full Text Available Reactive nitrogen compounds, specifically NOx and NO3, likely influence global organic aerosol levels. To assess these interactions, GEOS-Chem, a chemical transport model, is updated to include improved biogenic emissions (following MEGAN v2.1/2.04, a new organic aerosol tracer lumping scheme, aerosol from nitrate radical (NO3 oxidation of isoprene, and NOx-dependent terpene aerosol yields. As a result of significant nighttime terpene emissions, fast reaction of monoterpenes with the nitrate radical, and relatively high aerosol yields from NO3 oxidation, biogenic hydrocarbon-NO3 reactions are expected to be a major contributor to surface level aerosol concentrations in anthropogenically influenced areas such as the United States. By including aerosol from nitrate radical oxidation in GEOS-Chem, terpene aerosol approximately doubles and isoprene aerosol is enhanced by 30 to 40% in the Southeast United States. In terms of the global budget of organic aerosol, however, aerosol from nitrate radical oxidation is somewhat minor (slightly more than 3 Tg/yr due to the relatively high volatility of organic-NO3 oxidation products. Globally, 69 to 88 Tg/yr of organic aerosol is predicted to be produced annually, of which 14–15 Tg/yr is from oxidation of monoterpenes and sesquiterpenes and 8–9 Tg/yr from isoprene.

  15. Household hazardous waste

    DEFF Research Database (Denmark)

    Fjelsted, Lotte; Christensen, Thomas Højlund

    2007-01-01

    .) comprised 15-25% and foreign items comprised 10-20%. Water-based paint was the dominant part of the paint waste. The chemical composition of the paint waste and the paint-like waste was characterized by an analysis of 27 substances in seven waste fractions. The content of critical substances was tow and the......'Paint waste', a part of the 'household hazardous waste', amounting to approximately 5 tonnes was collected from recycling stations in two Danish cities. Sorting and analyses of the waste showed paint waste comprised approximately 65% of the mass, paint-like waste (cleaners, fillers, etc...... paint waste was less contaminated with heavy metals than was the ordinary household waste. This may suggest that households no longer need to source-segregate their paint if the household waste is incinerated, since the presence of a small quantity of solvent-based paint will not be harmful when...

  16. Release to the gas phase of metals, S and Cl during combustion of dedicated waste fractions

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul; van Lith, Simone Cornelia; Frandsen, Flemming;

    2010-01-01

    ) impregnated wood, shoes, automotive shredder waste and PVC (poly-vinyl-chloride). The waste fractions were characterized by use of wet chemical analysis, and, based on the chemical composition of the initial fuel sample and the ash residue after the experiments; the release of inorganic elements was......The release to the gas phase of inorganic elements such as alkali metals. Cl, S, and heavy metals in Waste-to-Energy (WtE) boilers is a challenge. Besides the risk of harmful emissions to the environment, inorganic elements released from the grate may cause severe ash deposition and corrosion...... and the link to the formation of fly ash and aerosols in full-scale waste incinerators. The release of metals, S and Cl from four dedicated waste fractions was quantified as a function of temperature in a lab-scale fixed-bed reactor. The waste fractions comprised chromated copper arsenate (CCA...

  17. Importance of Raman Lidar Aerosol Extinction Measurements for Aerosol-Cloud Interaction Studies

    Directory of Open Access Journals (Sweden)

    Han Zaw

    2016-01-01

    Full Text Available Using a UV Raman Lidar for aerosol extinction, and combining Microwave Radiometer derived Liquid Water Path (LWP with Multifilter Rotating Shadowband Radiometer derived Cloud Optical depth, to get cloud effective radius (Reff, we observe under certain specialized conditions, clear signatures of the Twomey Aerosol Indirect effect on cloud droplet properties which are consistent with the theoretical bounds. We also show that the measurement is very sensitive to how far the aerosol layer is from the cloud base and demonstrate that surface PM25 is far less useful. Measurements from both the DOE ARM site and new results at CCNY are presented.

  18. Monthly-averaged anthropogenic aerosol direct radiative forcing over the Mediterranean from AERONET derived aerosol properties

    OpenAIRE

    Bergamo, A.; A. M. Tafuro; Kinne, S.; De Tomasi, F.; Perrone, M. R.

    2008-01-01

    The all-sky direct radiative effect by anthropogenic aerosol (DREa) is calculated in the solar (0.3–4 μm) and infrared (4–200 μm) spectral ranges for six Mediterranean sites. The sites are differently affected by pollution and together reflect typical aerosol impacts that are expected over land sites of the central Mediterranean basin. Central to the simulations are aerosol optical properties from AERONET sun-/sky-photometer statistics for the year 2003. A discussion on the variability of the...

  19. Monthly-averaged anthropogenic aerosol direct radiative forcing over the Mediterranean based on AERONET aerosol properties

    OpenAIRE

    Bergamo, A.; A. M. Tafuro; Kinne, S.; De Tomasi, F.; Perrone, M. R.

    2008-01-01

    The all-sky direct radiative effect by anthropogenic aerosol (DREa) is calculated in the solar (0.3–4 μm) and infrared (4–200 μm) spectral ranges for six Mediterranean sites. The sites are differently affected by pollution and together reflect typical aerosol impacts that are expected over land and coastal sites of the central Mediterranean basin. Central to the simulations are aerosol optical properties from AERONET sun-/sky-photometer statistics for the year 2003. A d...

  20. Dark Targets, Aerosols, Clouds and Toys

    Science.gov (United States)

    Remer, L. A.

    2015-12-01

    Today if you use the Thomson-Reuters Science Citations Index to search for "aerosol*", across all scientific disciplines and years, with no constraints, and you sort by number of citations, you will find a 2005 paper published in the Journal of the Atmospheric Sciences in the top 20. This is the "The MODIS Aerosol Algorithm, Products and Validation". Although I am the first author, there are in total 12 co-authors who each made a significant intellectual contribution to the paper or to the algorithm, products and validation described. This paper, that algorithm, those people lie at the heart of a lineage of scientists whose collaborations and linked individual pursuits have made a significant contribution to our understanding of radiative transfer and climate, of aerosol properties and the global aerosol system, of cloud physics and aerosol-cloud interaction, and how to measure these parameters and maximize the science that can be obtained from those measurements. The 'lineage' had its origins across the globe, from Soviet Russia to France, from the U.S. to Israel, from the Himalayas, the Sahel, the metropolises of Sao Paulo, Taipei, and the cities of east and south Asia. It came together in the 1990s and 2000s at the NASA Goddard Space Flight Center, using cultural diversity as a strength to form a common culture of scientific creativity that continues to this day. The original algorithm has spawned daughter algorithms that are being applied to new satellite and airborne sensors. The original MODIS products have been fundamental to analyses as diverse as air quality monitoring and aerosol-cloud forcing. AERONET, designed originally for the need of validation, is now its own thriving institution, and the lineage continues to push forward to provide new technology for the coming generations.

  1. Formation of the natural sulfate aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Kerminen, V.M.; Hillamo, R.; Maekinen, M.; Virkkula, A.; Maekelae, T.; Pakkanen, T. [Helsinki Univ. (Finland). Dept. of Physics

    1996-12-31

    Anthropogenic sulfate aerosol, together with particles from biomass burning, may significantly reduce the climatic warming due to man-made greenhouse gases. The radiative forcing of aerosol particles is based on their ability to scatter and absorb solar radiation (direct effect), and on their influences on cloud albedos and lifetimes (indirect effect). The direct aerosol effect depends strongly on the size, number and chemical composition of particles, being greatest for particles of 0.1-1 {mu}m in diameter. The indirect aerosol effect is dictated by the number of particles being able to act as cloud condensation nuclei (CCN). For sulfate particles, the minimum CCN size in tropospheric clouds is of the order of 0.05-0.2 {mu}m. To improve aerosol parameterizations in future climate models, it is required that (1) both primary and secondary sources of various particle types will be characterized at a greater accuracy, and (2) the influences of various atmospheric processes on the spatial and temporal distribution of these particles and their physico-chemical properties are known much better than at the present. In estimating the climatic forcing due to the sulfate particles, one of the major problems is to distinguish between sulfur from anthropogenic sources and that of natural origin. Global emissions of biogenic and anthropogenic sulfate pre-cursors are comparable in magnitude, but over regional scales either of these two source types may dominate. The current presentation is devoted to discussing the natural sulfate aerosol, including the formation of sulfur-derived particles in the marine environment, and the use of particulate methanesulfonic acid (MSA) as a tracer for the natural sulfate

  2. Use of aerosols in lung function studies

    International Nuclear Information System (INIS)

    Since aerosol inhalation lung scintigraphy was introduced in 1965 following perfusion lung imaging, both imaging modalities have offered powerful tools not only for the study of respiratory lung function but also for the exploration of non-respiratory lung function studies. Visualization of the distribution of ventilation and perfusion in the lungs has made it possible to determine whether ventilation and perfusion are well matched or not, thus leading to the diagnosis of vascular diseases if perfusion is absent in the well ventilated lung regions, whereas airway diseases show matched ventilation and perfusion abnormalities. The reasons for the above principles have been physiologically clarified by perfusion and inhalation techniques using radioactive particulates, aerosols and radioactive gases. Regional ventilation always regulates regional perfusion; regional hypoventilation causes regional hypoxia which in turn causes hypoxic vasoconstriction and a consequent decrease in perfusion. Regional perfusion does not regulate regional ventilation except in the very early phase of perfusion changes when hypoperfusion can cause a transient bronchoconstriction and hypoventilation. This reaction disappears within 6 hours in dogs. Deposition patterns of inhaled aerosol in the lungs help differentiate the nature of the obstructive airways disease. Aerosol inhalation imaging can offer a unique technique for the study of mucociliary clearance function in the lungs. 'Radioaerosol inhalation lung cinescintigraphy' has made it possible to visualize the actual mucociliary clearance status in the lungs in vivo. Indexes to quantify the mucociliary clearance function have been proposed. Effects of pharmaceutical agents on mucociliary clearance function in the lungs can now be objectively evaluated by aerosol inhalation lung imaging and its quantification. The study of pulmonary epithelial permeability by inhalation of 99Tcm DTPA aerosol has also been mentioned. 26 refs, 8 figs, 3

  3. Preparation and characterization of magnetizable aerosols.

    Science.gov (United States)

    Baumann, Romy; Glöckl, Gunnar; Nagel, Stefan; Weitschies, Werner

    2012-04-11

    Magnetizable aerosols can be used for inhalative magnetic drug targeting in order to enhance the drug concentration at a certain target site within the lung. The aim of the present study was to clarify how a typical ferrofluid can be atomized in a reproducible way. The influence of the atomization principle, the concentration of magnetic nanoparticles within the carrier liquid and the addition of commonly used pharmaceutical excipients on the aerosol droplet size were investigated. Iron oxide (magnetite) nanoparticles were synthesized by alkaline precipitation of mixtures of iron(II)- and iron(III)-chloride and coated with citric acid. The resulting ferrofluid was characterized by photon correlation spectroscopy and vibrating sample magnetometry. Two different nebulizers (Pari Boy and eFlow) with different atomization principles were used to generate ferrofluid aerosols. A range of substances that influence the surface tension, viscosity, density or vapor pressure of the ferrofluid were added to investigate their impact on the generated aerosol droplets. The particle size was determined by laser diffraction. A stable ferrofluid with a magnetic core diameter of 10.7 ± 0.45 nm and a hydrodynamic diameter of 124 nm was nebulized by Pari Boy and eFlow. The aerosol droplet size of Pari Boy was approximately 2.5 μm and remained unaffected by the addition of substances that changed the physical properties of the solvent. The droplet size of aerosols generated by eFlow was approximately 5 μm. It was significantly reduced by the addition of Cremophor RH 40, glycerol, polyvinyl pyrrolidone and ethanol. PMID:22306649

  4. TEM investigations of microstructures of combustion aerosols

    International Nuclear Information System (INIS)

    In the incineration of organic material, apart from a series of gaseous pollutants, particulate pollutants or combustion aerosols also arise. The latter frequently consist of particles with a solid core of carbon to which a large number of inorganic and organic compounds are attached. These primarily include the polycyclic aromatic hydrocarbons (PAH) and their nitro-derivatives (NPAH), whose mutagenic or carcinogenic effect is known. The invisible particle sizes in the nanometer range, whose retention in the incineration off-gas is not state of the art, are of increasing significance for man and environment. On the one hand, they are deposited almost completely in the human lung. On the other hand, due to their fine dispersity they have along residence time in the atmosphere where they participate in chemical reactions and climatically significant processes. Important insights about the formation process of combustion aerosols are to be expected from the imaging of their microstructures in the transmission electron microscope (TEM). The present contribution describes the development and application of a representative sampling procedure for aerosols from a partial flow of flue gas from a fluidized-bed furnace. The method developed consists of electrically charging aerosol particles in situ and subsequently selectively precipitating them onto a microscope slide in an electric field. TEM studies of aerosol microstructures on the microscope slides revealed that in the combustion of petrol and heating oil under different combustion conditions in principle the same particle structures result, whereas in the incineration of used lubricating oil quite different particle structures were found. Results from the literature on aerosol microstructures in exhaust gases from petrol and diesel engines demonstrate agreement with the results of this study in the basic structure of the particles. (orig.)

  5. Nuclear wastes

    International Nuclear Information System (INIS)

    While evoking the effects of radioactivity, this publication issued by religious authorities first presents the different radioactive wastes (low level, low or medium level and short life, medium level and long life, high level and long life) and indicates their respective origins. It proposes a brief overview of solutions adopted for the storage of high level-long life radioactive wastes in different countries. It presents the French political and regulatory framework for such storage, indicates the envisaged solutions (deep geological storage, separation and transmutation, packaging and long duration surface or underground warehousing), discusses the content of the debate which took place before the adoption of the law of June 2006, and evokes the notion of reversibility. The next part addresses issues related to public information, and evokes public opinion regarding this storage issue. Some other issues are then discussed within the Church's perspective: the responsibility towards future generations, the transmission of a secured heritage to future generations, the research effort, dialog and transparency

  6. Radioactive wastes

    International Nuclear Information System (INIS)

    Here are gathered 1)the decrees (99-686 and 99-687) of the 3 rd of August 1999 relative to the researches on radioactive waste management. A local committee of information and follow-up has to be established on the site of each underground facility. The composition of this committee is determined here (99-686). 3 people will from now on be jointly ordered by the Minister of Economy, Finance and Industry and by the Secretary of State of Industry to conduct a preliminary dialogue for the choice of one or several sites on which previous works should be made before the construction of an underground facility (99-687). They take the opinion of the people's representatives, the associations and the concerned population and inform the Ministers of Environment, Energy and Research of the collected information. 2)the decree of the 3 rd of August 1999 authorizing the 'Agence nationale pour la gestion des dechets radioactifs' (ANDRA) to install and exploit an underground facility located in Bure (Meuse) and intended to study the deep geological deposits where could be stored radioactive wastes. (O.M.)

  7. Wastes processing

    Energy Technology Data Exchange (ETDEWEB)

    Farinet, J.L. (CIRAD-CA, 34 - Montpellier (France)); Copin, Y. (CEREMHER, 34 - Meze (France))

    1994-01-01

    The Transpaille procedure is used for the recovery and processing of organic wastes using methane fermentation; gas and compost are produced. The system was installed at the slaughterhouse in Thies, Senegal, in 1988-89. It consists of a 40 cubic metres horizontal cylinder. The slaughterhouse produces 480 metric tonnes of wastes per year and 35.5 cubic metres of biogas per day at a process temperature of 31 deg C. Lagooning is used for the first time as a water purification technique at a slaughterhouse in West Africa. This technique reproduces the process by which water purifies itself biologically, by accelerating and controlling the phenomenon. The procedure includes pre-processing, a decanter/digester and three lagoons. The organic matter is degraded by bacteria, producing water, carbon dioxide and mineral elements, which are then assimilated by micro-algae and macrophytes (Pistia stratiotes). The tropical climate is convenient for this processing method, which is optimum of temperatures of between 25 deg C and 35 deg C. (authors).

  8. Comparison of Aerosol Classification From Airborne High Spectral Resolution Lidar and the CALIPSO Vertical Feature Mask

    Science.gov (United States)

    Burton, Sharon P.; Ferrare, Rich A.; Omar, Ali H.; Vaughan, Mark A.; Rogers, Raymond R.; Hostetler, Chris a.; Hair, Johnathan W.; Obland, Michael D.; Butler, Carolyn F.; Cook, Anthony L.; Harper, David B.

    2012-01-01

    Knowledge of aerosol composition and vertical distribution is crucial for assessing the impact of aerosols on climate. In addition, aerosol classification is a key input to CALIOP aerosol retrievals, since CALIOP requires an inference of the lidar ratio in order to estimate the effects of aerosol extinction and backscattering. In contrast, the NASA airborne HSRL-1 directly measures both aerosol extinction and backscatter, and therefore the lidar ratio (extinction-to-backscatter ratio). Four aerosol intensive properties from HSRL-1 are combined to infer aerosol type. Aerosol classification results from HSRL-1 are used here to validate the CALIOP aerosol type inferences.

  9. Supermarket food waste

    OpenAIRE

    Eriksson, Mattias

    2015-01-01

    Food waste occurs along the entire food supply chain and gives rise to great financial losses and waste of natural resources. The retail stage of the supply chain contributes significant masses of waste. Causes of this waste need to be identified before potential waste reduction measures can be designed, tested and evaluated. Therefore this thesis quantified retail food waste and evaluated selected prevention and valorisation measures, in order to determine how the carbon footprint of food ca...

  10. Waste Characterization Methods

    Energy Technology Data Exchange (ETDEWEB)

    Vigil-Holterman, Luciana R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Felicia Danielle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-02

    This report discusses ways to classify waste as outlined by LANL. Waste Generators must make a waste determination and characterize regulated waste by appropriate analytical testing or use of acceptable knowledge (AK). Use of AK for characterization requires several source documents. Waste characterization documentation must be accurate, sufficient, and current (i.e., updated); relevant and traceable to the waste stream’s generation, characterization, and management; and not merely a list of information sources.

  11. Municipal Solid Waste management

    OpenAIRE

    Mirakovski, Dejan; Hadzi-Nikolova, Marija; Doneva, Nikolinka

    2010-01-01

    Waste management covers newly generated waste or waste from an onging process. When steps to reduce or even eliminate waste are to be considered, it is imperative that considerations should include total oversight, technical and management services of the total process.From raw material to the final product this includes technical project management expertise, technical project review and pollution prevention technical support and advocacy.Waste management also includes handling of waste, in...

  12. In situ aerosol characterization at Cape Verde Part 2: Parametrization of relative humidity- and wavelength-dependent aerosol optical properties

    OpenAIRE

    Schladitz, Alexander; Müller, Thomas; Nordmann, Stephan; Tesche, Matthias; Groß, Silke; Freudenthaler, Volker; Gasteiger, Josef; Wiedensohler, Alfred

    2011-01-01

    An observation-based numerical study of humidity-dependent aerosol optical properties of mixed marine and Saharan mineral dust aerosol is presented. An aerosol model was developed based on measured optical and microphysical properties to describe the marine and Saharan dust aerosol at Cape Verde. A wavelength-dependent optical equivalent imaginary part of the refractive index and a scattering non-sphericity factor for Saharan dust were derived. Simulations of humidity effects on optical prope...

  13. Carbonaceous aerosols and mineral dust in atmospheric outflow from the Indo-Gangetic Plain

    Science.gov (United States)

    Sarin, M.; Srinivas, B.; Rengarajan, R.

    2012-12-01

    Atmospheric carbonaceous aerosols and mineral dust over south and south-east Asia has been a subject of major debate over the past two decades because of their potential impact on the regional air quality and climate forcing. A comprehensive study through ground-based measurements and data-base for aerosol chemical composition (involving both organic and inorganic constituents) is, thus, essential to constrain the large uncertainties associated with the climate impact. Our systematic study from a downwind site (Kharagpur: 22.02N, 87.11E) in the Indo-Gangetic Plain (IGP) suggests large temporal variability in the atmospheric mass concentrations of mineral dust, organic and elemental carbon (OC, EC), water-soluble organic carbon (WSOC) and inorganic species (WSIS). This is attributed to seasonally varying anthropogenic emissions, their source strength, boundary layer dynamics, secondary aerosol formation and long-range transport of mineral dust from desert regions. Based on diagnostic ratios [OC/EC ≈ 7.0 ± 2.2, WSOC/OC ≈ 0.6 and K+/EC ≈ 0.48 ± 0.17], we document biomass burning emissions (wood-fuel and post-harvest agricultural-waste burning) as a major source of carbonaceous aerosols. The characteristic ratios: nss-SO42-/EC (3.9 ± 2.1), nss-SO42-/OC (0.61 ± 0.46), high abundance of SO42- (6.9 - 25.3 μg m-3) and SO42-/ΣWSIS = 45 - 77 % in the outflow provide better assessment of aerosol optical properties. The subsequent downwind transport of pollutants from the IGP significantly influences the chemical composition of aerosols over the Bay of Bengal. The dominance of aerosol SO42- in the marine atmospheric boundary layer (MABL) is evident from the wide-spread depletion of chloride with respect to sea-salt composition. The Ca/Al and Fe/Al ratios in the IGP-outflow, used as a proxy for the long-range transport of mineral dust, are consistent with those in the MABL. The mass closure for PM2.5 composition suggests that contribution of mineral dust (20

  14. TEM Study of SAFARI-2000 Aerosols

    Science.gov (United States)

    Buseck, Peter R.

    2004-01-01

    The aim of our research was to obtain data on the chemical and physical properties of individual aerosol particles from biomass smoke plume s in southern Africa and from air masses in the region that are affec ted by the smoke. We used analytical transmission electron microscopy (ATEM), including energy-dispersive X-ray spectrometry (EDS) and ele ctron energy-loss spectroscopy (EELS), and field-emission electron microscopy (FESEM) to study aerosol particles from several smoke and haz e samples and from a set of cloud samples.

  15. Pharmacokinetics of aerosol amphotericin B in rats.

    OpenAIRE

    Niki, Y.; Bernard, E M; Schmitt, H J; Tong, W P; Edwards, F F; Armstrong, D

    1990-01-01

    The distributions of amphotericin B (AmB) in tissue were compared after intraperitoneal or aerosol administration. Rats were sacrificed 24 h after receiving single or repeated daily doses; AmB concentrations in tissues were determined by high-performance liquid chromatography. After intraperitoneal doses of 4 mg/kg of body weight per day for 7 days, mean concentrations of AmB were 122.7, 55.2, and 4.31 micrograms/g in the spleen, liver, and lung, respectively. After aerosol doses (aero-AmB) o...

  16. Instantaneous aerosol dynamics in a turbulent flow

    KAUST Repository

    Zhou, Kun

    2012-01-01

    Dibutyl phthalate aerosol particles evolution dynamics in a turbulent mixing layer is simulated by means of direct numerical simulation for the flow field and the direct quadrature method of moments for the aerosol evolution. Most par-ticles are nucleated in a thin layer region corresponding to a specific narrow temperature range near the cool stream side. However, particles undergo high growth rate on the hot stream side due to condensation. Coagulation decreases the total particle number density at a rate which is highly correlated to the in-stantaneous number density.

  17. Aerosol delivery of synthetic lung surfactant

    Directory of Open Access Journals (Sweden)

    Frans J. Walther

    2014-05-01

    Full Text Available Background. Nasal continuous positive airway pressure (nCPAP is a widely accepted technique of non-invasive respiratory support in premature infants with respiratory distress syndrome due to lack of lung surfactant. If this approach fails, the next step is often intubation, mechanical ventilation (MV and intratracheal instillation of clinical lung surfactant. Objective. To investigate whether aerosol delivery of advanced synthetic lung surfactant, consisting of peptide mimics of surfactant proteins B and C (SP-B and SP-C and synthetic lipids, during nCPAP improves lung function in surfactant-deficient rabbits. Methods. Experimental synthetic lung surfactants were produced by formulating 3% Super Mini-B peptide (SMB surfactant, a highly surface active SP-B mimic, and a combination of 1.5% SMB and 1.5% of the SP-C mimic SP-Css ion-lock 1 (BC surfactant, with a synthetic lipid mixture. After testing aerosol generation using a vibrating membrane nebulizer and aerosol conditioning (particle size, surfactant composition and surface activity, we investigated the effects of aerosol delivery of synthetic SMB and BC surfactant preparations on oxygenation and lung compliance in saline-lavaged, surfactant-deficient rabbits, supported with either nCPAP or MV. Results. Particle size distribution of the surfactant aerosols was within the 1–3 µm distribution range and surfactant activity was not affected by aerosolization. At a dose equivalent to clinical surfactant therapy in premature infants (100 mg/kg, aerosol delivery of both synthetic surfactant preparations led to a quick and clinically relevant improvement in oxygenation and lung compliance in the rabbits. Lung function recovered to a greater extent in rabbits supported with MV than with nCPAP. BC surfactant outperformed SMB surfactant in improving lung function and was associated with higher phospholipid values in bronchoalveolar lavage fluid; these findings were irrespective of the type of

  18. Delivery of aerosolized drugs encapsulated in liposomes

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Yung-Sung; Lyons, C.R. [Univ. of New Mexico, Albuquerque, NM (United States); Schmid, M.H.

    1995-12-01

    Mycobacterium tuberculosis (Mtb) is an infectious disease that resides in the human lung. Due to the difficulty in completely killing off the disease in infected individuals, Mtb has developed drug-resistant forms and is on the rise in the human population. Therefore, ITRI and the University of New Mexico are collaborating to explore the treatment of Mtb by an aerosolized drug delivered directly to the lungs. In conclusion, it is feasible to obtain an appropriate size and concentration of the liposomes before and after aerosolization.

  19. Aerosol behaviour in an acoustic field

    International Nuclear Information System (INIS)

    The average size of an aerosol submitted to acoustic waves is increased. This results from coagulation of the finest particles on the largest ones. The mechanisms responsible for acoustic agglomeration are mentioned. An experimental apparatus was developed in order to control the evolution of aerosol distribution in an acoustic field. Important deposition on the walls of the agglomeration chamber was observed as a consequence of the acoustically induced turbulent flow. Finally, a dimensionless relationship was established between deposition rates and particle diameters as a function of experimental parameters (aeraulic and acoustic conditions, etc...)

  20. Aerosol monitoring in the PBL over big cities using a mobile eye safe LIDAR

    Science.gov (United States)

    Sauvage, Laurent; Chazette, Patrick

    2005-10-01

    The Laboratory of Science of Climate and Environment (CEA/ CNRS) and LEOSPHERE Company have jointly developed an eye safe, rugged and unattended high resolution scanning lidar ("easy lidar", www.lidar.fr). This system has been used in the frame of the POVA program and has been used in a compact version during the LISAIR (LIdar to Survey the AIR) program in May 2005 in the Paris city, France. The mobile lidar has been used to follow aerosol particles in highways subject to heavy traffic. High spatial and temporal resolution data on the entire planetary boundary layer (1.5 m and 1s respectively) allowed to monitor for aerosol load variability on board a moving car and also to detect for local sources. We observed the doubling of the optical thickness in the morning when traffic is high in the city ring. We also have shown local effect of waste burning plants and train stations. This new type of eye safe lidar will allow to monitor continuously the entire area of a town and suburbs, in order to detect main sources of pollution (transport, traffic jams, industrial plants, natural dust), follow in real time the evolution of the PBL height and provide an estimation of the mass concentration of the aerosol in the PBL.

  1. The influence of salt aerosol on alpha radiation detection by WIPP continuous air monitors

    International Nuclear Information System (INIS)

    Alpha continuous air monitors (CAMs) will be used at the Waste Isolation Pilot Plant (WIPP) to measure airborne transuranic radioactivity that might be present in air exhaust or in work-place areas. WIPP CAMs are important to health and safety because they are used to alert workers to airborne radioactivity, to actuate air-effluent filtration systems, and to detect airborne radioactivity so that the radioactivity can be confined in a limited area. In 1993, the Environmental Evaluation Group (EEG) reported that CAM operational performance was affected by salt aerosol, and subsequently, the WIPP CAM design and usage were modified. In this report, operational data and current theories on aerosol collection were reviewed to determine CAM quantitative performance limitations. Since 1993, the overall CAM performance appears to have improved, but anomalous alpha spectra are present when sampling-filter salt deposits are at normal to high levels. This report shows that sampling-filter salt deposits directly affect radon-thoron daughter alpha spectra and overall monitor efficiency. Previously it was assumed that aerosol was mechanically collected on the surface of CAM sampling filters, but this review suggests that electrostatic and other particle collection mechanisms are more important than previously thought. The mechanism of sampling-filter particle collection is critical to measurement of acute releases of radioactivity. 41 refs

  2. Waste Transfer Stations

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund

    tion and transport is usually the most costly part of any waste management system; and when waste is transported over a considerable distance or for a long time, transferring the waste from the collection vehicles to more efficient transportation may be economically beneficial. This involves a...... transfer station where the transfer takes place. These stations may also be accessible by private people, offering flexibility to the waste system, including facilities for bulky waste, household hazardous waste and recyclables. Waste transfer may also take place on the collection route from small...... describes the main features of waste transfer stations, including some considerations about the economical aspects on when transfer is advisable....

  3. Waste Transfer Stations

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund

    2011-01-01

    tion and transport is usually the most costly part of any waste management system; and when waste is transported over a considerable distance or for a long time, transferring the waste from the collection vehicles to more efficient transportation may be economically beneficial. This involves a...... transfer station where the transfer takes place. These stations may also be accessible by private people, offering flexibility to the waste system, including facilities for bulky waste, household hazardous waste and recyclables. Waste transfer may also take place on the collection route from small...... describes the main features of waste transfer stations, including some considerations about the economical aspects on when transfer is advisable....

  4. Potential for waste reduction

    International Nuclear Information System (INIS)

    The author focuses on wastes considered hazardous under the Resource Conservation and Recovery Act. This chapter discusses wastes that are of interest as well as the factors affecting the quantity of waste considered available for waste reduction. Estimates are provided of the quantities of wastes generated. Estimates of the potential for waste reduction are meaningful only to the extent that one can understand the amount of waste actually being generated. Estimates of waste reduction potential are summarized from a variety of government and nongovernment sources

  5. Atmospheric oxidation of isoprene and 1,3-Butadiene: influence of aerosol acidity and Relative humidity on secondary organic aerosol

    Science.gov (United States)

    The effects of acidic seed aerosols on the formation of secondary organic aerosol (SOA)have been examined in a number of previous studies, several of which have observed strong linear correlations between the aerosol acidity (measured as nmol H+ per m3 air s...

  6. UV Aerosol Indices from SCIAMACHY: introducing the SCattering Index (SCI

    Directory of Open Access Journals (Sweden)

    T. Wagner

    2009-12-01

    Full Text Available The Absorbing Aerosol Index (AAI is a useful tool for detecting aerosols that absorb UV radiation – especially in cases where other aerosol retrievals fail, such as over bright surfaces (e.g. desert and in the presence of clouds. The AAI does not, however, consider contributions from scattering (hardly absorbing aerosols and clouds: they cause negative AAI values and are usually disregarded. In this paper, we demonstrate the use of the AAI's negative counterpart, the SCattering Index (SCI to detect scattering aerosols. Consideration of the full UV Aerosol Index scale is of importance if the Aerosol Index is to be used for the quantification of aerosol absorption in the future.

    Maps of seasonally averaged SCI show significantly enhanced values in summer in Southeast USA and Southeast Asia, pointing to a high production of scattering aerosols (presumably mainly sulphate aerosols and secondary organic aerosols in this season. The application of a cloud filter makes the presence of scattering aerosols even more clear. Radiative transfer calculations were performed to investigate the sensitivity of AAI and SCI to cloud parameters, and it is demonstrated that clouds cause significant SCI, in some special cases even small AAI values. The results from cloud modelling imply that cloud effects need to be taken into account when AAI and SCI are used in a quantitative manner.

    The paper concludes with a comparison of aerosol parameters from AERONET and our Aerosol Indices (AAI and SCI from SCIAMACHY, where reasonable agreement was found for six AERONET stations in Southeast USA, Southeast Asia, and Africa. These findings corroborate the suitability of SCI as a tool to detect scattering aerosols.

  7. Aerosol Remote Sensing in Polar Regions

    Science.gov (United States)

    Tomasi, Claudio; Kokhanovsky, Alexander A.; Lupi, Angelo; Ritter, Christoph; Smirnov, Alexander; O'Neill, Norman T.; Stone, Robert S.; Holben, Brent N.; Nyeki, Stephan; Wehrli, Christoph

    2014-01-01

    Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness tau(lambda) at visible and near-infrared wavelengths, from which best-fit values of Ångström's exponent alpha were calculated. Analyzing these data, the monthly mean values of tau(0.50 micrometers) and alpha and the relative frequency histograms of the daily mean values of both parameters were determined for winter-spring and summer-autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of alpha versus tau(0.50 micrometers) showed: (i) a considerable increase in tau(0.50 micrometers) for the Arctic aerosol from summer to winter-spring, without marked changes in alpha; and (ii) a marked increase in tau(0.50 micrometer) passing from the Antarctic Plateau to coastal sites, whereas alpha decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of tau(lambda) and alpha at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterize vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ålesund. Satellite-based MODIS, MISR, and AATSR retrievals of tau(lambda) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were

  8. Analyses of CsI aerosol deposition in aerosol behavior tests in WIND project

    International Nuclear Information System (INIS)

    The aerosol deposition tests have been performed in WIND project at JAERI to characterize the aerosol behavior. The aerosol deposition tests named WAV1-D and WAV2-D were analyzed by aerosol behavior analysis codes, JAERI's ART and SNL's VICTORIA. The comparison calculation was performed for the confirmation of the analytical capabilities of the both codes and improvement of the models in ART. The deposition mass calculated by ART was larger than that by VICTORIA. This discrepancy is caused by differences in model for FP vapor condensation onto the wall surface. In the WAV2-D test, in which boric acid was placed on the floor area of the test section prior to the deposition phase to simulate the PWR primary coolant, there was a discrepancy in deposition mass between analytical results in both codes and experimental results. The discrepancy may be caused by existence of boric acid which is not considered in the codes. (author)

  9. Aerosol isotopic ammonium signatures over the remote Atlantic Ocean

    Science.gov (United States)

    Lin, C. T.; Jickells, T. D.; Baker, A. R.; Marca, A.; Johnson, M. T.

    2016-05-01

    We report aerosol ammonium 15N signatures for samples collected from research cruises on the South Atlantic and Caribbean using a new high sensitivity method. We confirm a pattern of isotopic signals from generally light (δ15N -5 to -10‰), for aerosols with very low (ocean, to generally heavier values (δ15N +5 to +10‰), for aerosols collected in temperate and tropical latitudes and with higher ammonium concentrations (>2  nmol m-3). We discuss whether this reflects a mixing of aerosols from two end-members (polluted continental and remote marine emissions), or isotopic fractionation during aerosol transport.

  10. Determination of Aerosol Particle Diameter Using Cascade Impactor Procedure

    International Nuclear Information System (INIS)

    Determination of aerosol particle size distribution has been done using a low pressure Andersen's cascade impactor with 13 stages. The aerosol has been sampled with flow rate of aerosol sampling of 28.3 Ipm. Preliminary study result shows that aerosol in the simulation chamber was spread in monomodal distribution with Mass Median Aerodynamic Diameter of 4.9 μm. The aerosol measurement in Japan Power Demonstration Reactor has been spread in trimodal distribution with Activity Median Aerodynamic Diameter equal to 13.3 μm. The use of mylar as impaction plate instead of aluminum foil gives good result

  11. Intercomparison of CALIOP and MODIS aerosol optical depth retrievals

    OpenAIRE

    Kittaka, C.; Winker, D. M.; M. A. Vaughan; Omar, A.; Remer, L. A.

    2010-01-01

    The Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) is carried on the CALIPSO satellite and has acquired global aerosol profiles since June 2006. CALIPSO is flown in formation with the Aqua satellite as part of the A-train satellite constellation, so that a large number of coincident aerosol observations are available from CALIOP and the MODIS-Aqua instrument. This study compares column aerosol optical depth at 0.532 μm derived from CALIOP aerosol profiles with MODIS-Aqua 0.55 μm ae...

  12. Aerosol/Cloud Measurements Using Coherent Wind Doppler Lidars

    Science.gov (United States)

    Royer, Philippe; Boquet, Matthieu; Cariou, Jean-Pierre; Sauvage, Laurent; Parmentier, Rémy

    2016-06-01

    The accurate localization and characterization of aerosol and cloud layers is crucial for climate studies (aerosol indirect effect), meteorology (Planetary Boundary Layer PBL height), site monitoring (industrial emissions, mining,…) and natural hazards (thunderstorms, volcanic eruptions). LEOSPHERE has recently developed aerosol/cloud detection and characterization on WINDCUBE long range Coherent Wind Doppler Lidars (CWDL). These new features combine wind and backscatter intensity informations (Carrier-to-Noise Ratio CNR) in order to detect (aerosol/cloud base and top, PBL height) and to characterize atmospheric structures (attenuated backscatter, depolarization ratio). For each aerosol/cloud functionality the method is described, limitations are discussed and examples are given to illustrate the performances.

  13. Radioactive aerosols of 'Ukryttya' object in 1986-2006 years

    International Nuclear Information System (INIS)

    Radioactive aerosols of 'Ukryttya' object in its premises and its industrial site are seen. In seven parts the mechanisms and sources of aerosol generation at explosion of the block 4 of the ChNPP in 1986, at building and operation of 'Ukryttya' object are presented. The dynamics of radionuclide composition, concentrations and size distributions are analyzed. The means and methods for aerosol sampling, using of collective and personal protection devices, the problems of control of radioactive aerosol inhalation are seen. The main attention is paid to aerosols with diameter up to 10 mkm

  14. Influence of aerosol upon radon concentration of radon chamber

    International Nuclear Information System (INIS)

    On the basis of theoretical analysis, the influence on the radon concentration of radon chamber by the experiment of filling the radon chamber with aerosol, and the absorption of radon daughter on aerosol under the condition of different radon concentration and aerosol concentration was described. The results of experiment showed that: Aerosol did not affect the stability of the radon concentration of the radon chamber, but different aerosol concentration will change the combination state of radon daughter, thus it will affect the diffusion coefficient of radon daughter, so it will affect the results of the measure of the gross measuring instrument. (authors)

  15. Introduction to Waste Management

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund

    Solid waste management is as old as human civilization, although only considered an engineering discipline for about one century. The change from the previous focus on public cleansing of the cities to modern waste management was primarily driven by industrialization, which introduced new materials...... and chemicals, dramatically changing the types and composition of waste, and by urbanization making waste management in urban areas a complicated and costly logistic operation. This book focuses on waste that commonly appears in the municipal waste management system. This chapter gives an introduction...... to modern waste management, including issues as waste definition, problems associated with waste, waste management criteria and approaches to waste management. Later chapters introduce aspects of engineering (Chapter 1.2), economics (Chapter 1.3) and regulation (Chapter 1.4)....

  16. Do anthropogenic or coastal aerosol sources impact on a clean marine aerosol signature at Mace Head?

    Science.gov (United States)

    O'Dowd, C.; Ceburnis, D.; Ovadnevaite, J.; Rinaldi, M.; Facchini, M. C.

    2013-03-01

    Atmospheric aerosols have been sampled and characterised at the Mace Head North East (N.E.) Atlantic atmospheric research station since 1958, with many interesting phenomena being discovered. However, with the range of new discoveries and scientific advances, there has been a range of concomitant criticisms challenging the representativeness of aerosol sampled at the station to that of aerosol over the open ocean. Two recurring criticisms relate to the lack of representativeness due to enhanced coastal sources, thereby leading to artificially high values to aerosol parameters, and to the influence of long-range transport of anthropogenic aerosol and its potential dominance over, or drowning-out of, a natural marine aerosol signal. Here we review the results of previous experimental studies into marine aerosols over the N.E. Atlantic and at Mace Head with the aim of evaluating their representativeness relative to that of an open ocean aerosol with negligible anthropogenic influence. Particular focus is given to organic matter (OM) aerosol. In summary, no correlation was found between OM and black carbon (BC) either at BC levels of 0-15 or 15-50 ng m-3, suggesting that OM concentrations up to peak values of 3.8 μg m-3 are predominantly natural in origin. Sophisticated carbon isotope analysis and aerosol mass spectral finger printing corroborate the natural source of OM with 80% biogenic source apportionment being observed for general clean air conditions, rising to 98% during specific primary marine organic plumes when peak concentrations >3 μg m-3 are observed. A range of other experiments are discussed which corroborate the dominance of a marine signal under Mace Head clean air criteria along. Further, analysis of a series of experiments conducted at Mace Head conclude that negligible coastal, surf zone, or tidal effects are discernible in the submicron size range for sampling heights of 7 m and above. The Mace Head clean air criteria ensures anthropogenic and

  17. Do anthropogenic or coastal aerosol sources impact on a clean marine aerosol signature at Mace Head?

    Directory of Open Access Journals (Sweden)

    C. O'Dowd

    2013-03-01

    Full Text Available Atmospheric aerosols have been sampled and characterised at the Mace Head North East (N.E. Atlantic atmospheric research station since 1958, with many interesting phenomena being discovered. However, with the range of new discoveries and scientific advances, there has been a range of concomitant criticisms challenging the representativeness of aerosol sampled at the station to that of aerosol over the open ocean. Two recurring criticisms relate to the lack of representativeness due to enhanced coastal sources, thereby leading to artificially high values to aerosol parameters, and to the influence of long-range transport of anthropogenic aerosol and its potential dominance over, or drowning-out of, a natural marine aerosol signal. Here we review the results of previous experimental studies into marine aerosols over the N.E. Atlantic and at Mace Head with the aim of evaluating their representativeness relative to that of an open ocean aerosol with negligible anthropogenic influence. Particular focus is given to organic matter (OM aerosol. In summary, no correlation was found between OM and black carbon (BC either at BC levels of 0–15 or 15–50 ng m−3, suggesting that OM concentrations up to peak values of 3.8 μg m−3 are predominantly natural in origin. Sophisticated carbon isotope analysis and aerosol mass spectral finger printing corroborate the natural source of OM with 80% biogenic source apportionment being observed for general clean air conditions, rising to 98% during specific primary marine organic plumes when peak concentrations >3 μg m−3 are observed. A range of other experiments are discussed which corroborate the dominance of a marine signal under Mace Head clean air criteria along. Further, analysis of a series of experiments conducted at Mace Head conclude that negligible coastal, surf zone, or tidal effects are discernible in the submicron size range for sampling heights of 7 m and above. The Mace Head clean air criteria

  18. Aerosol climatology: on the discrimination of aerosol types over four AERONET sites

    Directory of Open Access Journals (Sweden)

    D. G. Kaskaoutis

    2007-05-01

    Full Text Available Aerosols have a significant regional and global effect on climate, which is about equal in magnitude but opposite in sign to that of greenhouse gases. Nevertheless, the aerosol climatic effect changes strongly with space and time because of the large variability of aerosol physical and optical properties, which is due to the variety of their sources, which are natural, and anthropogenic, and their dependence on the prevailing meteorological and atmospheric conditions. Characterization of aerosol properties is of major importance for the assessment of their role for climate. In the present study, 3-year AErosol RObotic NETwork (AERONET data from ground-based sunphotometer measurements are used to establish climatologies of aerosol optical depth (AOD and Ångström exponent α in several key locations of the world, characteristic of different atmospheric environments. Using daily mean values of AOD at 500 nm (AOD500 and Ångström exponent at the pair of wavelengths 440 and 870 nm (α 440–870, a discrimination of the different aerosol types occurring in each location is achieved. For this discrimination, appropriate thresholds for AOD500 and α 440–870 are applied. The discrimination of aerosol types in each location is made on an annual and seasonal basis. It is shown that a single aerosol type in a given location can exist only under specific conditions (e.g. intense forest fires or dust outbreaks, while the presence of well-mixed aerosols is the accustomed situation. Background clean aerosol conditions (AOD500<0.06 are mostly found over remote oceanic surfaces occurring on average in ~56.7% of total cases, while this situation is quite rare over land (occurrence of 3.8–13.7%. Our analysis indicates that these percentages change significantly from season to season. The spectral dependence of AOD exhibits large differences between the examined locations, while it exhibits a strong

  19. Aerosol physical and optical properties in the Eastern Mediterranean Basin, Crete, from Aerosol Robotic Network data

    Directory of Open Access Journals (Sweden)

    A. Fotiadi

    2006-01-01

    Full Text Available In this study, we investigate the aerosol optical properties, namely aerosol extinction optical thickness (AOT, Angström parameter and size distribution over the Eastern Mediterranean Basin, using spectral measurements from the recently established FORTH (Foundation for Research and Technology-Hellas AERONET station in Crete, for the two-year period 2003–2004. The location of the FORTH-AERONET station offers a unique opportunity to monitor aerosols from different sources. Maximum values of AOT are found primarily in spring, which together with small values of the Angström parameter indicate dust transported from African deserts, whereas the minimum values of AOT occur in winter. In autumn, large AOT values observed at near-infrared wavelengths arise also from dust transport. In summer, large AOT values at ultraviolet (340 nm and visible wavelengths (500 nm, together with large values of the Angström parameter, are associated with transport of fine aerosols of urban/industrial and biomass burning origin. The Angström parameter values vary on a daily basis within the range 0.05–2.20, and on a monthly basis within the range 0.68–1.9. This behaviour, together with broad frequency distributions and back-trajectory analyses, indicates a great variety of aerosol types over the study region including dust, urban-industrial and biomass-burning pollution, and maritime, as well as mixed aerosol types. Large temporal variability is observed in AOT, Angström parameter, aerosol content and size. The fine and coarse aerosol modes persist throughout the year, with the coarse mode dominant except in summer. The highest values of AOT are related primarily to southeasterly winds, associated with coarse aerosols, and to a less extent to northwesterly winds associated with fine aerosols. The results of this study show that the FORTH AERONET station in Crete is well suited for studying the transport and mixing of different types of aerosols from a variety

  20. Nuclear waste

    International Nuclear Information System (INIS)

    The Department of Energy is awarding grants to the state of Nevada for the state's participation in DOE's program to investigate Yucca Mountain as a possible site for the disposal of civilian nuclear waste. This report has found that DOE's financial assistance budget request of $15 million for Nevada's fiscal year 1990 was not based on the amount the state requested but rather was derived by increasing Nevada's grant funds from the previous year in proportion to the increase that DOE requested for its own activities at the Nevada site. DOE's evaluations of Nevada's requests are performed too late to be used in DOE's budget formulation process because Nevada has been applying for financial assistance at about the same time that DOE submits its budget request to Congress

  1. AEROSOL MEASUREMENTS IN THE SUBMICRON SIZE RANGE, STUDIES WITH AN AEROSOL CENTRIFUGE, A NEW DIFFUSION BATTERY, A LOW PRESSURE IMPACTOR AND AN ADVANCED CONDENSATION NUCLEI COUNTER

    Science.gov (United States)

    The report summarizes the investigations of four aerosol classifiers which cover finite, but overlapping ranges of the aerosol particle size spectrum. The first part is concerned with a cylindrical aerosol centrifuge, which measures aerodynamic equivalent diameters precisely. Thi...

  2. Release of Free DNA by Membrane-Impaired Bacterial Aerosols Due to Aerosolization and Air Sampling

    OpenAIRE

    Zhen, Huajun; Han, Taewon; Fennell, Donna E.; Mainelis, Gediminas

    2013-01-01

    We report here that stress experienced by bacteria due to aerosolization and air sampling can result in severe membrane impairment, leading to the release of DNA as free molecules. Escherichia coli and Bacillus atrophaeus bacteria were aerosolized and then either collected directly into liquid or collected using other collection media and then transferred into liquid. The amount of DNA released was quantified as the cell membrane damage index (ID), i.e., the number of 16S rRNA gene copies in ...

  3. Recent Improvements to CALIOP Level 3 Aerosol Profile Product for Global 3-D Aerosol Extinction Characterization

    Science.gov (United States)

    Tackett, J. L.; Getzewich, B. J.; Winker, D. M.; Vaughan, M. A.

    2015-12-01

    With nine years of retrievals, the CALIOP level 3 aerosol profile product provides an unprecedented synopsis of aerosol extinction in three dimensions and the potential to quantify changes in aerosol distributions over time. The CALIOP level 3 aerosol profile product, initially released as a beta product in 2011, reports monthly averages of quality-screened aerosol extinction profiles on a uniform latitude/longitude grid for different cloud-cover scenarios, called "sky conditions". This presentation demonstrates improvements to the second version of the product which will be released in September 2015. The largest improvements are the new sky condition definitions which parse the atmosphere into "cloud-free" views accessible to passive remote sensors, "all-sky" views accessible to active remote sensors and "cloudy-sky" views for opaque and transparent clouds which were previously inaccessible to passive remote sensors. Taken together, the new sky conditions comprehensively summarize CALIOP aerosol extinction profiles for a broad range of scientific queries. In addition to dust-only extinction profiles, the new version will include polluted-dust and smoke-only extinction averages. A new method is adopted for averaging dust-only extinction profiles to reduce high biases which exist in the beta version of the level 3 aerosol profile product. This presentation justifies the new averaging methodology and demonstrates vertical profiles of dust and smoke extinction over Africa during the biomass burning season. Another crucial advancement demonstrated in this presentation is a new approach for computing monthly mean aerosol optical depth which removes low biases reported in the beta version - a scenario unique to lidar datasets.

  4. Reallocation in modal aerosol models: impacts on predicting aerosol radiative effects

    OpenAIRE

    Korhola, T.; H. Kokkola; Korhonen, H.; A.-I. Partanen; Laaksonen, A.; Lehtinen, K. E. J.; S. Romakkaniemi

    2013-01-01

    In atmospheric modelling applications the aerosol particle size distribution is commonly represented by modal approach, in which particles in different size ranges are described with log-normal modes within predetermined size ranges. Such method includes numerical reallocation of particles from a mode to another for example during particle growth, leading to potentially artificial changes in the aerosol size distribution. In this study we analysed how this reallocation affects climatologicall...

  5. Reallocation in modal aerosol models: impacts on predicting aerosol radiative effects

    Science.gov (United States)

    Korhola, T.; Kokkola, H.; Korhonen, H.; Partanen, A.-I.; Laaksonen, A.; Lehtinen, K. E. J.; Romakkaniemi, S.

    2014-01-01

    Atmospheric models often represent the aerosol particle size distribution with a modal approach, in which particles are described with log-normal modes within predetermined size ranges. This approach reallocates particles numerically from one mode to another for example during particle growth, potentially leading to artificial changes in the aerosol size distribution. In this study we analysed how the modal reallocation affects climate-relevant variables: cloud droplet number concentration (CDNC), aerosol-cloud interaction parameter (ACI) and light extinction coefficient (qext). The ACI parameter gives the response of CDNC to a change in total aerosol number concentration. We compared these variables between a modal model (with and without reallocation routines) and a high resolution sectional model, which was considered a reference model. We analysed the relative differences in the chosen variables in four experiments designed to assess the influence of atmospheric aerosol processes. We find that limiting the allowed size ranges of the modes, and subsequent remapping of the distribution, leads almost always to an underestimation of cloud droplet number concentrations (by up to 100%) and an overestimation of light extinction (by up to 20%). On the other hand, the aerosol-cloud interaction parameter can be either over- or underestimated by the reallocating model, depending on the conditions. For example, in the case of atmospheric new particle formation events followed by rapid particle growth, the reallocation can cause on average a 10% overestimation of the ACI parameter. Thus it is shown that the reallocation affects the ability of a model to estimate aerosol climate effects accurately, and this should be taken into account when using and developing aerosol models.

  6. Reallocation in modal aerosol models: impacts on predicting aerosol radiative effects

    OpenAIRE

    Korhola, T.; H. Kokkola; Korhonen, H.; Partanen, A.-I.; Laaksonen, A.; Lehtinen, K. E. J.; S. Romakkaniemi

    2014-01-01

    Atmospheric models often represent the aerosol particle size distribution with a modal approach, in which particles are described with log-normal modes within predetermined size ranges. This approach reallocates particles numerically from one mode to another for example during particle growth, potentially leading to artificial changes in the aerosol size distribution. In this study we analysed how the modal reallocation affects climate-relevant variables: cloud droplet numbe...

  7. New trajectory driven aerosol and chemical process model: chemical and aerosol Lagrangian model (CALM)

    OpenAIRE

    Tunved, P.; D. G. Partridge; Korhonen, H.

    2010-01-01

    A new Chemical and Aerosol Lagrangian Model (CALM) have been developed and tested. The model incorporates all central aerosol dynamical processes, from nucleation, condensation, coagulation and deposition to cloud formation and in-cloud processing. The model is tested and evaluated against observations performed at the SMEAR II station located at Hyytiälä (61°51' N, 24°17' E) over a time period of two years, 2000–2001. The model shows good agreement with measurements thro...

  8. Climate implications of carbonaceous aerosols: An aerosol microphysical study using the GISS/MATRIX climate model

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Susanne E.; Menon, Surabi; Koch, Dorothy; Bond, Tami; Tsigaridis, Kostas

    2010-04-09

    Recently, attention has been drawn towards black carbon aerosols as a likely short-term climate warming mitigation candidate. However the global and regional impacts of the direct, cloud-indirect and semi-direct forcing effects are highly uncertain, due to the complex nature of aerosol evolution and its climate interactions. Black carbon is directly released as particle into the atmosphere, but then interacts with other gases and particles through condensation and coagulation processes leading to further aerosol growth, aging and internal mixing. A detailed aerosol microphysical scheme, MATRIX, embedded within the global GISS modelE includes the above processes that determine the lifecycle and climate impact of aerosols. This study presents a quantitative assessment of the impact of microphysical processes involving black carbon, such as emission size distributions and optical properties on aerosol cloud activation and radiative forcing. Our best estimate for net direct and indirect aerosol radiative forcing change is -0.56 W/m{sup 2} between 1750 and 2000. However, the direct and indirect aerosol effects are very sensitive to the black and organic carbon size distribution and consequential mixing state. The net radiative forcing change can vary between -0.32 to -0.75 W/m{sup 2} depending on these carbonaceous particle properties. Assuming that sulfates, nitrates and secondary organics form a coating shell around a black carbon core, rather than forming a uniformly mixed particles, changes the overall net radiative forcing from a negative to a positive number. Black carbon mitigation scenarios showed generally a benefit when mainly black carbon sources such as diesel emissions are reduced, reducing organic and black carbon sources such as bio-fuels, does not lead to reduced warming.

  9. Measuring Aerosol Optical Depth (AOD and Aerosol Profiles Simultaneously with a Camera Lidar

    Directory of Open Access Journals (Sweden)

    Barnes John

    2016-01-01

    Full Text Available CLidar or camera lidar is a simple, inexpensive technique to measure nighttime tropospheric aerosol profiles. Stars in the raw data images used in the CLidar analysis can also be used to calculate aerosol optical depth simultaneously. A single star can be used with the Langley method or multiple star pairs can be used to reduce the error. The estimated error from data taken under clear sky conditions at Mauna Loa Observatory is approximately +/- 0.01.

  10. Aerosol Indices Derived from MODIS Data for Indicating Aerosol-Induced Air Pollution

    Directory of Open Access Journals (Sweden)

    Junliang He

    2014-02-01

    Full Text Available Aerosol optical depth (AOD is a critical variable in estimating aerosol concentration in the atmosphere, evaluating severity of atmospheric pollution, and studying their impact on climate. With the assistance of the 6S radiative transfer model, we simulated apparent reflectancein relation to AOD in each Moderate Resolution Imaging Spectroradiometer (MODIS waveband in this study. The closeness of the relationship was used to identify the most and least sensitive MODIS wavebands. These two bands were then used to construct three aerosol indices (difference, ratio, and normalized difference for estimating AOD quickly and effectively. The three indices were correlated, respectively, with in situ measured AOD at the Aerosol Robotic NETwork (AERONET Lake Taihu, Beijing, and Xianghe stations. It is found that apparent reflectance of the blue waveband (band 3 is the most sensitive to AOD while the mid-infrared wavelength (band 7 is the least sensitive. The difference aerosol index is the most accurate in indicating aerosol-induced atmospheric pollution with a correlation coefficient of 0.585, 0.860, 0.685, and 0.333 at the Lake Taihu station, 0.721, 0.839, 0.795, and 0.629 at the Beijing station, and 0.778, 0.782, 0.837, and 0.643 at the Xianghe station in spring, summer, autumn and winter, respectively. It is concluded that the newly proposed difference aerosol index can be used effectively to study the level of aerosol-induced air pollution from MODIS satellite imagery with relative ease.

  11. Aerosol composition and sources during the Chinese Spring Festival: fireworks, secondary aerosol, and holiday effects

    Science.gov (United States)

    Jiang, Q.; Sun, Y. L.; Wang, Z.; Yin, Y.

    2015-06-01

    Aerosol particles were characterized by an Aerodyne aerosol chemical speciation monitor along with various collocated instruments in Beijing, China, to investigate the role of fireworks (FW) and secondary aerosol in particulate pollution during the Chinese Spring Festival of 2013. Three FW events, exerting significant and short-term impacts on fine particles (PM2.5), were observed on the days of Lunar New Year, Lunar Fifth Day, and Lantern Festival. The FW were shown to have a large impact on non-refractory potassium, chloride, sulfate, and organics in submicron aerosol (PM1), of which FW organics appeared to be emitted mainly in secondary, with its mass spectrum resembling that of secondary organic aerosol (SOA). Pollution events (PEs) and clean periods (CPs) alternated routinely throughout the study. Secondary particulate matter (SPM = SOA + sulfate + nitrate + ammonium) dominated the total PM1 mass on average, accounting for 63-82% during nine PEs in this study. The elevated contributions of secondary species during PEs resulted in a higher mass extinction efficiency of PM1 (6.4 m2 g-1) than during CPs (4.4 m2 g-1). The Chinese Spring Festival also provides a unique opportunity to study the impact of reduced anthropogenic emissions on aerosol chemistry in the city. Primary species showed ubiquitous reductions during the holiday period with the largest reduction being in cooking organic aerosol (OA; 69%), in nitrogen monoxide (54%), and in coal combustion OA (28%). Secondary sulfate, however, remained only slightly changed, and the SOA and the total PM2.5 even slightly increased. Our results have significant implications for controlling local primary source emissions during PEs, e.g., cooking and traffic activities. Controlling these factors might have a limited effect on improving air quality in the megacity of Beijing, due to the dominance of SPM from regional transport in aerosol particle composition.

  12. Aerosol Indices Derived from MODIS Data for Indicating Aerosol-Induced Air Pollution

    OpenAIRE

    Junliang He; Yong Zha; Jiahua Zhang; Jay Gao

    2014-01-01

    Aerosol optical depth (AOD) is a critical variable in estimating aerosol concentration in the atmosphere, evaluating severity of atmospheric pollution, and studying their impact on climate. With the assistance of the 6S radiative transfer model, we simulated apparent reflectancein relation to AOD in each Moderate Resolution Imaging Spectroradiometer (MODIS) waveband in this study. The closeness of the relationship was used to identify the most and least sensitive MODIS wavebands. These two ba...

  13. Development of aerosol transport and transformation models in PROFIT code. Coagulation of aerosol particles

    International Nuclear Information System (INIS)

    The problems of simulation of aerosol particles distribution in primary coolant circuit are discussed. The correlation dependences for collision centres and aerosol particles coagulation under the action of Brownian, turbulent, gradient and gravitational mechanisms with account of the accumulation effect are plotted. The dependences obtained take account of mutual influence of different coagulation mechanisms. The presented correlations for coagulation centre are implanted into PROFIT code

  14. A study of the attachment of thoron decay products to aerosols using an aerosol centrifuge

    International Nuclear Information System (INIS)

    The physical attachment of radioactive decay products (particulate, not gas) to polydisperse fluorescein aerosal particles in two size ranges 0.1 μM-0.33 μM radius and 0.25 μM-1.35 μM radius has been studied under dynamic conditions with a view to find the fraction of thoron decay products attached to the aerosals and the particle size distribution of the host aerosols in the atmosphere of uranium mines. The experimental set-up and procedure are described. An aerosol cloud of fluorescein was introduced into a reaction chamber containing a steady source of thoron and decay products were allowed to interact and attach to the aerosols in the chamber. To simulate conditions normally encountered in uranium mining and milling operations, the concentration of aerosol particles was kept high as compared to the number of decay products. The Lovelace Aerosol Particle Separator, which is an advanced, continuous centrifugal aerosol separator, was used to sample and separate the tagged aerosols into various size groups. The radioactivity associated with each group was determined. The results show the same dependence of attachment of decay products on the size of aerosol particles as predicted by the diffusion theory proposed by Lassen and Rau (1960), even though the experimental conditions of the present study do not conform to those required to satisfy the above mentioned diffusion theory. The method employed in this work to study attachment is reproducible and simple and can be adopted in uranium and thorium mines and associated processing industries. (M.G.B.)

  15. Status of the ORNL Aerosol Release and Transport Project

    International Nuclear Information System (INIS)

    The behavior of aerosols assumed to be characteristic of those generated during light water reactor (LWR) accident sequences and released into containment is being studied. Recent activities in the ORNL Aerosol Release and Transport Project include studies of (1) the thermal hydraulic conditions existing during Nuclear Safety Pilot Plant (NSPP) aerosol tests in steam-air environments, (2) the thermal output and aerosol mass generation rates for plasma torch aerosol generators, and (3) the influence of humidity on the shape of agglomerated aerosols of various materials. A new Aerosol-Moisture Interaction Test (AMIT) facility was prepared at the NSPP site to accommodate the aerosol shape studies; several tests with Fe2O3 aerosol have been conducted. In addition to the above activities a special study was conducted to determine the suitability of the technique of aerosol production by plasma torch under the operating conditions of future tests of the LWR Aerosol Containment Experiments (LACE) at the Hanford Engineering Development Laboratory. 3 refs., 2 figs., 7 tabs

  16. The study on differentiated particle size sampling technology of aerosols

    International Nuclear Information System (INIS)

    This article introduces basic principle of differentiated particle size sampling technology of aerosols. This sampling technology is used to conduct a experimental research on the aerosols particles size distribution of uranium and radon and it's daughters. Experimental results showed that the part of radon and it's daughters aerosols particles size smaller than 0.43 μm reached 76.4%. The part of radon and it's daughters aerosols particles size less than 1 μm reached 96.3%. The part of uranium aerosol particles size larger than 4.7 μm under specific conditions is 94%, the part of aerosol particles size larger than 10 μm is 72%. According to the experiment's result, we designed a new sampling equipments that cutting size is 1 μm to collect samples of aerosols, and it is used in the separation efficiency experiments of 241Am aerosols. Experimental results showed that the separation efficiency of 241Am aerosols can reach 94.2%. Thus, using the differentiated particle size sampling technology to collect samples of plutonium aerosols, in the sampling process can reduce the effect of natural background aerosols. (authors)

  17. Management Of Solid Waste Matter

    International Nuclear Information System (INIS)

    This book is written with data from, 84 Karlsruhe symposium, which tells US general introduction of waste disposal such as actualization of waste disposal, related law and direction of waste disposal, collect and transportation of waste matter, preconditioning of waste, collect of waste and recirculation, cases of recirculation, optimal process of waste incineration of waste, composting of waste, disposal of harmful waste, RDF with pilot and operational plant and sanitary landfill method.

  18. Carbonaceous aerosols and pollutants over Delhi urban environment: Temporal evolution, source apportionment and radiative forcing

    International Nuclear Information System (INIS)

    Particulate matter (PM2.5) samples were collected over Delhi, India during January to December 2012 and analysed for carbonaceous aerosols and inorganic ions (SO42− and NO3−) in order to examine variations in atmospheric chemistry, combustion sources and influence of long-range transport. The PM2.5 samples are measured (offline) via medium volume air samplers and analysed gravimetrically for carbonaceous (organic carbon, OC; elemental carbon, EC) aerosols and inorganic ions (SO42− and NO3−). Furthermore, continuous (online) measurements of PM2.5 (via Beta-attenuation analyser), black carbon (BC) mass concentration (via Magee scientific Aethalometer) and carbon monoxide (via CO-analyser) are carried out. PM2.5 (online) range from 18.2 to 500.6 μg m−3 (annual mean of 124.6 ± 87.9 μg m−3) exhibiting higher night-time (129.4 μg m−3) than daytime (103.8 μg m−3) concentrations. The online concentrations are 38% and 28% lower than the offline during night and day, respectively. In general, larger night-time concentrations are found for the BC, OC, NO3−and SO42−, which are seasonally dependent with larger differences during late post-monsoon and winter. The high correlation (R2 = 0.74) between OC and EC along with the OC/EC of 7.09 (day time) and 4.55 (night-time), suggest significant influence of biomass-burning emissions (burning of wood and agricultural waste) as well as secondary organic aerosol formation during daytime. Concentrated weighted trajectory (CWT) analysis reveals that the potential sources for the carbonaceous aerosols and pollutants are local emissions within the urban environment and transported smoke from agricultural burning in northwest India during post-monsoon. BC radiative forcing estimates result in very high atmospheric heating rates (~ 1.8–2.0 K day−1) due to agricultural burning effects during the 2012 post-monsoon season. - Highlights: • Very high PM2.5 (> 200 µg m−3) levels over Delhi during agricultural

  19. Carbonaceous aerosols and pollutants over Delhi urban environment: Temporal evolution, source apportionment and radiative forcing

    Energy Technology Data Exchange (ETDEWEB)

    Bisht, D.S. [Indian Institute of Tropical Meteorology, New Delhi (India); Dumka, U.C., E-mail: dumka@aries.res.in [Aryabhatta Research Institute of Observational Sciences, Nainital (India); Kaskaoutis, D.G. [School of Natural Sciences, Shiv Nadar University, Tehsil Dadri (India); Pipal, A.S. [Department of Chemistry, Savitribai Phule Pune University, Pune (India); Srivastava, A.K. [Indian Institute of Tropical Meteorology, New Delhi (India); Soni, V.K.; Attri, S.D.; Sateesh, M. [India Meteorology Department, Lodhi Road, New Delhi (India); Tiwari, S. [Indian Institute of Tropical Meteorology, New Delhi (India)

    2015-07-15

    Particulate matter (PM{sub 2.5}) samples were collected over Delhi, India during January to December 2012 and analysed for carbonaceous aerosols and inorganic ions (SO{sub 4}{sup 2−} and NO{sub 3}{sup −}) in order to examine variations in atmospheric chemistry, combustion sources and influence of long-range transport. The PM{sub 2.5} samples are measured (offline) via medium volume air samplers and analysed gravimetrically for carbonaceous (organic carbon, OC; elemental carbon, EC) aerosols and inorganic ions (SO{sub 4}{sup 2−} and NO{sub 3}{sup −}). Furthermore, continuous (online) measurements of PM{sub 2.5} (via Beta-attenuation analyser), black carbon (BC) mass concentration (via Magee scientific Aethalometer) and carbon monoxide (via CO-analyser) are carried out. PM{sub 2.5} (online) range from 18.2 to 500.6 μg m{sup −3} (annual mean of 124.6 ± 87.9 μg m{sup −3}) exhibiting higher night-time (129.4 μg m{sup −3}) than daytime (103.8 μg m{sup −3}) concentrations. The online concentrations are 38% and 28% lower than the offline during night and day, respectively. In general, larger night-time concentrations are found for the BC, OC, NO{sub 3}{sup −}and SO{sub 4}{sup 2−}, which are seasonally dependent with larger differences during late post-monsoon and winter. The high correlation (R{sup 2} = 0.74) between OC and EC along with the OC/EC of 7.09 (day time) and 4.55 (night-time), suggest significant influence of biomass-burning emissions (burning of wood and agricultural waste) as well as secondary organic aerosol formation during daytime. Concentrated weighted trajectory (CWT) analysis reveals that the potential sources for the carbonaceous aerosols and pollutants are local emissions within the urban environment and transported smoke from agricultural burning in northwest India during post-monsoon. BC radiative forcing estimates result in very high atmospheric heating rates (~ 1.8–2.0 K day{sup −1}) due to agricultural burning effects

  20. Seasonal and inter-annual variability of the aerosol content in Cairo (Egypt) as deduced from the comparison of MODIS aerosol retrievals with direct AERONET measurements

    Science.gov (United States)

    El-Metwally, M.; Alfaro, S. C.; Abdel Wahab, M. M.; Zakey, A. S.; Chatenet, B.

    2010-07-01

    frequent in winter. Conversely, the AOD increases in summer because particle accumulation is favored in this season by the absence of precipitations and by atmospheric stability. However, AOD maxima are obtained in April (0.38 ± 0.02) and in October (0.36 ± 0.03) when particles produced outside of the city by natural processes (wind-erosion of desert surfaces) or by human activities (burning of agricultural wastes in the Nile Delta) are transported by prevailing winds and contribute significantly to the enhancement of the city's aerosol burden.