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Sample records for aerosols teresa application

  1. TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5

    Energy Technology Data Exchange (ETDEWEB)

    Annette Rohr

    2006-03-01

    TERESA (Toxicological Evaluation of Realistic Emissions of Source Aerosols) involves exposing laboratory rats to realistic coal-fired power plant and mobile source emissions to help determine the relative toxicity of these PM sources. There are three coal-fired power plants in the TERESA program; this report describes the results of fieldwork conducted at the first plant, located in the Upper Midwest. The project was technically challenging by virtue of its novel design and requirement for the development of new techniques. By examining aged, atmospherically transformed aerosol derived from power plant stack emissions, we were able to evaluate the toxicity of PM derived from coal combustion in a manner that more accurately reflects the exposure of concern than existing methodologies. TERESA also involves assessment of actual plant emissions in a field setting--an important strength since it reduces the question of representativeness of emissions. A sampling system was developed and assembled to draw emissions from the stack; stack sampling conducted according to standard EPA protocol suggested that the sampled emissions are representative of those exiting the stack into the atmosphere. Two mobile laboratories were then outfitted for the study: (1) a chemical laboratory in which the atmospheric aging was conducted and which housed the bulk of the analytical equipment; and (2) a toxicological laboratory, which contained animal caging and the exposure apparatus. Animal exposures were carried out from May-November 2004 to a number of simulated atmospheric scenarios. Toxicological endpoints included (1) pulmonary function and breathing pattern; (2) bronchoalveolar lavage fluid cytological and biochemical analyses; (3) blood cytological analyses; (4) in vivo oxidative stress in heart and lung tissue; and (5) heart and lung histopathology. Results indicated no differences between exposed and control animals in any of the endpoints examined. Exposure concentrations for the

  2. TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5

    Energy Technology Data Exchange (ETDEWEB)

    Annette C. Rohr; Petros Koutrakis; John Godleski

    2011-03-31

    Determining the health impacts of different sources and components of fine particulate matter (PM2.5) is an important scientific goal, because PM is a complex mixture of both inorganic and organic constituents that likely differ in their potential to cause adverse health outcomes. The TERESA (Toxicological Evaluation of Realistic Emissions of Source Aerosols) study focused on two PM sources - coal-fired power plants and mobile sources - and sought to investigate the toxicological effects of exposure to realistic emissions from these sources. The DOE-EPRI Cooperative Agreement covered the performance and analysis of field experiments at three power plants. The mobile source component consisted of experiments conducted at a traffic tunnel in Boston; these activities were funded through the Harvard-EPA Particulate Matter Research Center and will be reported separately in the peer-reviewed literature. TERESA attempted to delineate health effects of primary particles, secondary (aged) particles, and mixtures of these with common atmospheric constituents. The study involved withdrawal of emissions directly from power plant stacks, followed by aging and atmospheric transformation of emissions in a mobile laboratory in a manner that simulated downwind power plant plume processing. Secondary organic aerosol (SOA) derived from the biogenic volatile organic compound {alpha}-pinene was added in some experiments, and in others ammonia was added to neutralize strong acidity. Specifically, four scenarios were studied at each plant: primary particles (P); secondary (oxidized) particles (PO); oxidized particles + secondary organic aerosol (SOA) (POS); and oxidized and neutralized particles + SOA (PONS). Extensive exposure characterization was carried out, including gas-phase and particulate species. Male Sprague Dawley rats were exposed for 6 hours to filtered air or different atmospheric mixtures. Toxicological endpoints included (1) breathing pattern; (2) bronchoalveolar lavage

  3. TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5

    Energy Technology Data Exchange (ETDEWEB)

    Annette C. Rohr; Petros Koutrakis; John Godleski

    2011-03-31

    Determining the health impacts of different sources and components of fine particulate matter (PM2.5) is an important scientific goal, because PM is a complex mixture of both inorganic and organic constituents that likely differ in their potential to cause adverse health outcomes. The TERESA (Toxicological Evaluation of Realistic Emissions of Source Aerosols) study focused on two PM sources - coal-fired power plants and mobile sources - and sought to investigate the toxicological effects of exposure to realistic emissions from these sources. The DOE-EPRI Cooperative Agreement covered the performance and analysis of field experiments at three power plants. The mobile source component consisted of experiments conducted at a traffic tunnel in Boston; these activities were funded through the Harvard-EPA Particulate Matter Research Center and will be reported separately in the peer-reviewed literature. TERESA attempted to delineate health effects of primary particles, secondary (aged) particles, and mixtures of these with common atmospheric constituents. The study involved withdrawal of emissions directly from power plant stacks, followed by aging and atmospheric transformation of emissions in a mobile laboratory in a manner that simulated downwind power plant plume processing. Secondary organic aerosol (SOA) derived from the biogenic volatile organic compound {alpha}-pinene was added in some experiments, and in others ammonia was added to neutralize strong acidity. Specifically, four scenarios were studied at each plant: primary particles (P); secondary (oxidized) particles (PO); oxidized particles + secondary organic aerosol (SOA) (POS); and oxidized and neutralized particles + SOA (PONS). Extensive exposure characterization was carried out, including gas-phase and particulate species. Male Sprague Dawley rats were exposed for 6 hours to filtered air or different atmospheric mixtures. Toxicological endpoints included (1) breathing pattern; (2) bronchoalveolar lavage

  4. TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5

    Energy Technology Data Exchange (ETDEWEB)

    Annette Rohr

    2004-12-02

    This report documents progress made on the subject project during the period of March 1, 2004 through August 31, 2004. The TERESA Study is designed to investigate the role played by specific emissions sources and components in the induction of adverse health effects by examining the relative toxicity of coal combustion and mobile source (gasoline and/or diesel engine) emissions and their oxidative products. The study involves on-site sampling, dilution, and aging of coal combustion emissions at three coal-fired power plants, as well as mobile source emissions, followed by animal exposures incorporating a number of toxicological endpoints. The DOE-EPRI Cooperative Agreement (henceforth referred to as ''the Agreement'') for which this technical progress report has been prepared covers the analysis and interpretation of the field data collected at the first power plant (henceforth referred to as Plant 0, and located in the Upper Midwest), followed by the performance and analysis of similar field experiments at two additional coal-fired power plants (Plants 1 and 2) utilizing different coal types and with different plant configurations. Significant progress was made on the Project during this reporting period, with field work being initiated at Plant 0. Initial testing of the stack sampling system and reaction apparatus revealed that primary particle concentrations were lower than expected in the emissions entering the mobile chemical laboratory. Initial animal exposures to primary emissions were carried out (Scenario 1) to ensure successful implementation of all study methodologies and toxicological assessments. Results indicated no significant toxicological effects in response to primary emissions exposures. Exposures were then carried out to diluted, oxidized, neutralized emissions with the addition of secondary organic aerosol (Scenario 5), both during the day and also at night when primary particle concentrations in the sampled stack emissions

  5. Toxicological Evaluation of Realistic Emissions of Source Aerosols (TERESA): Application to Power Plant-Derived PM2.5

    Energy Technology Data Exchange (ETDEWEB)

    Annette Rohr

    2007-02-28

    This report documents progress made on the subject project during the period of September 1, 2007 through February 28, 2007. The TERESA Study is designed to investigate the role played by specific emissions sources and components in the induction of adverse health effects by examining the relative toxicity of coal combustion and mobile source (gasoline and/or diesel engine) emissions and their oxidative products. The study involves on-site sampling, dilution, and aging of coal combustion emissions at three coal-fired power plants, as well as mobile source emissions, followed by animal exposures incorporating a number of toxicological endpoints. The DOE-EPRI Cooperative Agreement (henceforth referred to as ''the Agreement'') for which this technical progress report has been prepared covers the performance and analysis of field experiments at the first TERESA plant, located in the Upper Midwest and henceforth referred to as Plant 0, and at two additional coal-fired power plants (Plants 1 and 2) utilizing different coal types and with different plant configurations. During this reporting period, fieldwork was completed at Plant 2, located in the Midwest. The following scenarios were completed: (1) July 19-22: POS (oxidized + SOA); (2) July 25-28: PONS (oxidized + neutralized + SOA); (3) August 8-13: P (primary); (4) August 14-15: POS; (5) August 16-17: POS (MI rats); (6) August 28-31: OS (oxidized + SOA, without primary particles); (7) September 1-4: O (oxidized, no primary particles); (8) September 6-9: S (SOA, no primary particles); and (9) September 19-22: PO (oxidized). Results indicated some biological effects with some scenarios. Also during this reporting period, the annual meeting of the TERESA Technical Advisory Committee was held at the Harvard School of Public Health in Boston. During the next reporting period, data analyses will continue for Plant 2 as well as for pooled data from all three plants. Manuscripts documenting the overall

  6. TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWDER PLANT-DERIVED PM 2.5

    Energy Technology Data Exchange (ETDEWEB)

    Annette Rohr

    2006-08-31

    This report documents progress made on the subject project during the period of March 1, 2006 through August 31, 2006. The TERESA Study is designed to investigate the role played by specific emissions sources and components in the induction of adverse health effects by examining the relative toxicity of coal combustion and mobile source (gasoline and/or diesel engine) emissions and their oxidative products. The study involves on-site sampling, dilution, and aging of coal combustion emissions at three coal-fired power plants, as well as mobile source emissions, followed by animal exposures incorporating a number of toxicological endpoints. The DOE-EPRI Cooperative Agreement (henceforth referred to as ''the Agreement'') for which this technical progress report has been prepared covers the performance and analysis of field experiments at the first TERESA plant, located in the Upper Midwest and henceforth referred to as Plant 0, and at two additional coal-fired power plants (Plants 1 and 2) utilizing different coal types and with different plant configurations. During this reporting period, data processing and analyses were completed for exposure and toxicological data collected during the field campaign at Plant 1, located in the Southeast. Toxicological results indicate some pulmonary, oxidative stress, and cardiovascular responses to certain exposure scenarios. Fieldwork at Plant 2, located in the Midwest, began on July 19, 2006. The following scenarios were completed: July 19-22: POS (oxidized + SOA); July 25-28: PONS (oxidized + neutralized + SOA); August 8-13: P (primary); August 14-15: POS; August 16-17: POS (MI rats); August 28-31: OS (oxidized + SOA, without primary particles); September 1-4: O (oxidized, no primary particles); and September 6-9: S (SOA, no primary particles). During the next reporting period, we will report complete exposure and toxicological results for Plant 2. Planning will begin for the mobile source component of the

  7. TOXICOLOGICAL EVALUATION OF REALISTIC EMISSIONS OF SOURCE AEROSOLS (TERESA): APPLICATION TO POWER PLANT-DERIVED PM2.5

    Energy Technology Data Exchange (ETDEWEB)

    Annette Rohr

    2006-03-31

    This report documents progress made on the subject project during the period of September 1, 2005 through February 28, 2006. The TERESA Study is designed to investigate the role played by specific emissions sources and components in the induction of adverse health effects by examining the relative toxicity of coal combustion and mobile source (gasoline and/or diesel engine) emissions and their oxidative products. The study involves on-site sampling, dilution, and aging of coal combustion emissions at three coal-fired power plants, as well as mobile source emissions, followed by animal exposures incorporating a number of toxicological endpoints. The DOE-EPRI Cooperative Agreement (henceforth referred to as ''the Agreement'') for which this technical progress report has been prepared covers the performance and analysis of field experiments at the first TERESA plant, located in the Upper Midwest and henceforth referred to as Plant 0, and at two additional coal-fired power plants (Plants 1 and 2) utilizing different coal types and with different plant configurations. During this reporting period, data processing and analyses were completed for exposure and toxicological data collected during the field campaign at Plant 1, located in the Southeast. To recap from the previous progress report, Stage I toxicological assessments were carried out in normal Sprague-Dawley rats, and Stage II assessments were carried out in a compromised model (myocardial infarction-MI-model). Normal rats were exposed to the following atmospheric scenarios: (1) primary particles; (2) oxidized emissions; (3) oxidized emissions + SOA--this scenario was repeated; and (4) oxidized emissions + ammonia + SOA. Compromised animals were exposed to oxidized emissions + SOA (this scenario was also conducted in replicate). Mass concentrations in exposure atmospheres ranged from 13.9 {micro}g/m{sup 3} for the primary particle scenario (P) to 385 {micro}g/m{sup 3} for one of the oxidized

  8. Clarice com Teresa

    Directory of Open Access Journals (Sweden)

    Gustavo Fujarra Carmona

    2015-04-01

    Full Text Available Pretendemos com o presente artigo, revelar as possíveis convergências e divergências a respeito do caráter místico das obras de Clarice Lispector e de Santa Teresa d'Ávila. Para tanto, estabeleceremos um diálogo entre a obra e a vida destas duas autoras, além de trazer à discussão, os estudos de Lacan, Millot e Kristeva acerca da relação entre o gozo (outro e a escritura. Acreditamos, deste modo, ser possível dar nova luz às suas obras e perceber como estas duas se correlacionam, no que diz respeito à dimensão mística de suas escrituras, na busca do Real e do Gozo Outro, cada uma, à sua maneira.

  9. Need samad maastikud / Teresa Gali-Izard

    Index Scriptorium Estoniae

    Gali-Izard, Teresa

    2006-01-01

    Hispaania maastikuarhitekti ja põllumajandusinseneri Teresa Gali-Izardi (sünd. 1968) tekst tema 2005. a. Barcelonas Land & Scape'i seerias ilmunud raamatu "The Same Landscapes. Ideas and Interpretations" (Editorial Gustavo Gili) sissejuhatusest

  10. Teresa y Luis, Luis y Teresa. Dos santos en tiempos recios

    Directory of Open Access Journals (Sweden)

    Emilio Callado Estela

    2016-06-01

    Full Text Available El presente artículo analiza la relación entre dos grandes santos españoles de la Contrarreforma Católica, Teresa de Jesús y el dominico fray Luis Bertrán. The present article analyses the relation between two big Spanish saints of the Catholic Counterreformation, Teresa de Jesus and the Dominican monk Luis Bertrán.

  11. Últimas tardes con Teresa

    Directory of Open Access Journals (Sweden)

    Hugo Ruiz Rojas

    1966-08-01

    Full Text Available Ultimas tardes con Teresa, del escritor español Juan Marsé, viene a llamar la atención sobre este joven autor, que ya en sus libros anteriores, Esta cara de la luna y Encerrados con un solo juguete, había demostrado claras dotes de novelista, puesto que no solo tenía algo que decir sino que sabía también cómo decirlo.

  12. Santa Teresa y sus cartas, historia de los sentimientos

    Directory of Open Access Journals (Sweden)

    Egido, Teófanes

    2015-12-01

    Full Text Available Historical reflection on a peculiar dimension of St. Teresa of Jesus: the expression of her feelings in her writings, particularly in her abundant letters. The article focuses on the sense of humor, the joyfulness, and the importance of laughter in St. Teresa language, and also on the feeling of endearment with her family, with her order, with fray Juan de la Cruz. Ample space is dedicated to the tenderness towards girls in her convents. St. Teresa of Jesus appears as transgressor of 16th century social behaviours.Reflexión histórica sobre una dimensión peculiar de santa Teresa de Jesús: la expresión de sus sentimientos en sus escritos, de forma más especial en sus cartas abundantes. El artículo se centra en el sentido del humor, de la alegría, en la importancia de la risa en el lenguaje de santa Teresa y en el sentimiento de ternura con su familia, con su orden, con fray Juan de la Cruz. Se dedica un espacio amplio a la ternura hacia las niñas en sus conventos. Aparece santa Teresa de Jesús como trasgresora de los comportamientos sociales del siglo XVI.

  13. Aerosol Filtration Application Using Fibrous Media An Industrial Perspective

    Institute of Scientific and Technical Information of China (English)

    杨传芳

    2012-01-01

    Filtration of aerosol particles using non-woven fibrous media is a common practice for air cleaning. It has found wide applications in industries and our daily lives. This paper overviews some of these applications and provides an industrial perspective. It starts from discussing aerosol filtration theory, followed by a brief review on the advancement of filtration media. After that, filtration applications in respiratory protection, dust collection, and engine in-take air cleaning are elaborated. These are the areas that the author sees as the typical needed ones in China's fast pace economical development endeavor, where air filtration enables the protection of human health, environment and equipment for sustainability.

  14. Teresa Uzeda e i suoi Maîtres

    Directory of Open Access Journals (Sweden)

    Rosalba Galvagno

    2013-12-01

    Full Text Available La biografia diTeresa Uzeda narrata da Federico De Roberto nell’Illusione (1891, il primo grande romanzo del ciclo degli Uzedainsieme a I Viceré (1894 e a L’imperio (1929, comprende anche l’istruzionedella giovane eroina, che comincia a studiare dapprima - ha 10 anni all’iniziodel romanzo - sotto la direzione di Miss, per essere poi seguita da altriprofessori di lettere, di storia, di disegno, di canto, fino all’età di 17 annicirca. Ma, accanto all’istruzione ‘scolastica’, Teresa avrà accesso, graziealla sua devotissima serva Stefana, all’universo incantato e perturbante dellefiabe, e quindi, spinta dalla sua trasgressiva curiositas, all’universo altrettanto incantato e periglioso deiromanzi e del teatro, il melodramma innanzitutto.Quale Bildung si prefigura allora per ildestino di Teresa, questa infelice, incompresa e originalissima Bovarysiciliana?

  15. Santa Teresa de Jesús, su guion de vida

    OpenAIRE

    2015-01-01

    En este artículo se estudia la niñez, adolescencia y juventud de San - ta Teresa de Jesús, Santa Teresa de Ávila, la fundadora de las carmelitas descalzas, mística, escritora, doctora de la Iglesia católica, y patrona de los escritores en lengua española. El objetivo principal del trabajo es sa- ber porque decidió hacerse religiosa, y cómo cuando rondaba los 40 años y tras la muerte de su padre, decide comenzar su gran obra, fundando las carmelitas descalzas y extendiendo su congregación por ...

  16. Santa Teresa de Jesús, su guion de vida

    Directory of Open Access Journals (Sweden)

    Carmen Thous Tuset

    2015-01-01

    Full Text Available En este artículo se estudia la niñez, adolescencia y juventud de San - ta Teresa de Jesús, Santa Teresa de Ávila, la fundadora de las carmelitas descalzas, mística, escritora, doctora de la Iglesia católica, y patrona de los escritores en lengua española. El objetivo principal del trabajo es sa- ber porque decidió hacerse religiosa, y cómo cuando rondaba los 40 años y tras la muerte de su padre, decide comenzar su gran obra, fundando las carmelitas descalzas y extendiendo su congregación por toda España. Para ello la analizaremos desde la metodología humanística de su guion de vida, de acuerdo a la teoría del Análisis Transaccional del doctor Eric Berne. Los resultados demuestran que Teresa tuvo un guion marcado por la religiosidad de su madre y también condicionado por su padre. El re- sultado es que sólo pudo crear su propio guion de vida de triunfadora tras la muerte de ambos, naciendo entonces Teresa de Jesús y expandiendo su fecundidad espiritual, mística y literaria.

  17. Country western singer Teresa is congratulated by Daniel Goldin

    Science.gov (United States)

    1999-01-01

    After her performance at the Apollo/Saturn V Center, country western recording artist Teresa gets a congratulatory hug from NASA Administrator Daniel Goldin. Teresa performed a song, 'Brave New Girls,' written for astronaut Catherine 'Cady' Coleman, mission specialist on STS-93. She entertained participants and attendees of a women's forum held in the center earlier in the day. The attendees are planning to view the launch of STS-93 at the Banana Creek viewing sight. Much attention has been generated over the launch due to Commander Eileen M. Collins, the first woman to serve as commander of a Shuttle mission. Liftoff is scheduled for July 20 at 12:36 a.m. EDT.

  18. Teaching of Astronomy at Teresa Martin College. (Breton Title: Ensino de Astronomia Nas Faculdades Teresa Martin.) Enseñanza de la Astronomia en la Facultad Teresa Martin

    Science.gov (United States)

    Azevedo Sobreira, Paulo Henrique

    2005-12-01

    Courses with exclusive Astronomy contents did not exist at (FATEMA) Teresa Martin College's program until the end of 2002. In 2001, a series of educational experiments started in courses and classes of Astronomy at Mathematics and Geography departments. This actions culminated with the insertion of Teaching of Astronomy as a study theme in the course of Independent Studies for Mathematics professors in 2005. Até o final de 2002 inexistiam na grade curricular das Faculdades Integradas Teresa Martin (FATEMA) cadeiras com conteúdos exclusivos de Astronomia. A partir do ano de 2001 iniciou-se uma série de experiências educacionais através de modelos de cursos e de aulas de Astronomia nos Departamentos de Matemática e de Geografia, o que culminou com a inserção do Ensino de Astronomia como temática da disciplina de Estudos Independentes para o curso de Licenciatura em Matemática, em 2005. Hasta el final de 2002 no había en el currículo dela Facultad TeresaMartín (FATEMA) en San Pablo - SP, Brasil, disciplinas con contenidos exclusivos de Astronomía. A partir del año 2001 comenzó una secuencia de experimentos educacionales de carrera y de clases de Astronomía en los Departamentos de Matemática y Geografía, culminando en la implantación de clases de Enseñanza dela Astronomíaenla Licenciaturaen Matemática, en el año de 2003, y de la cátedra de extensión en Cosmografía parala Licenciaturaen Geografía.

  19. Aerosol Remote Sensing Applications for Airborne Multiangle, Multispectral Shortwave Radiometers

    Science.gov (United States)

    von Bismarck, Jonas; Ruhtz, Thomas; Starace, Marco; Hollstein, André; Preusker, René; Fischer, Jürgen

    2010-05-01

    and ground based operations of the instruments so far, only two exemplary campaigns shall be introduced here. FUBEX in July 2008 was the first airborne campaign with FUBISS-ASA2, FUBISS-ZENITH and AMSSP-EM simultaneously mounted on the Cessna 207T of the Institute for Space Sciences, based in Berlin. Vertical radiation profiles recorded on July 28 in 2008 where used for a first application of the introduced inversion algorithm. In Oktober/November 2009, FUBISS-ASA2 and FUBISS-ZENITH where mounted on the German research icebreaker FS Polarstern, crossing the Atlantic on its cruise from Bremerhaven (Germany) to Punta Arenas (Chile). Measurements where performed throughout the whole cruise on days with a variety of different atmospheric conditions, as a Saharan dust outbreak over Cape Verde, typical marine conditions with salt particles in the marine boundary layer and also pristine conditions in the southern Atlantic. Access to the data of other instruments aboard the ship, as a Raman-Lidar, a cloud camera, weather station, and a microwave radiometer, provided valuable a priori information for processing and calibration of the measurements. The results may be of special interest for the validation of satellite aerosol products.

  20. 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.

  1. A 10-year global gridded Aerosol Optical Thickness Reanalysis for climate and applied applications

    Science.gov (United States)

    Lynch, P.; Reid, J. S.; Zhang, J.; Westphal, D. L.; Campbell, J. R.; Curtis, C. A.; Hegg, D.; Hyer, E. J.; Sessions, W.; Shi, Y.; Turk, J.

    2013-12-01

    While standalone satellite and model aerosol products see wide utilization, there is a significant need of a best-available fused product on a regular grid for numerous climate and applied applications. Remote sensing and modeling technologies have now advanced to a point where aerosol data assimilation is an operational reality at numerous centers. It is inevitable that, like meteorological reanalyses, aerosol reanalyses will see heavy use in the near future. A first long term, 2003-2012 global 1x1 degree and 6-hourly aerosol optical thickness (AOT) reanalysis product has been generated. The goal of this effort is not only for climate applications, but to generate a dataset that can be used by the US Navy to understand operationally hindering aerosol events, aerosol impacts on numerical weather prediction, and application of electro-optical technologies. The reanalysis utilizes Navy Aerosol Analysis and Prediction System (NAAPS) at its core and assimilates quality controlled collection 5 Moderate Resolution Imaging Spectroradiometer (MODIS) AOD with minor corrections from Multi-angle Imaging SpectroRaditometer (MISR). A subset of this product includes Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) lidar assimilation since its launch in mid-2006. Surface aerosol sources, including dust and smoke, in the aerosol model have been regionally tuned so that fine and coarse mode AOTs best match those resolve by ground-based Aerosol Robotic Network (AERONET). The AOT difference between the model and satellite AOT is then used to adjust other aerosol processes, eg., sources, dry deposition, etc. Aerosol wet deposition is constrained with satellite-retrieved precipitation. The final AOT reanalysis is shown to exhibit good agreement with AERONET. Here we review the development of the reanalysis and consider issues particular to aerosol reanalyses that make them distinct from standard meteorological reanalyses. Considerations are also made for extending such work

  2. 77 FR 14058 - Santa Teresa Southern Railroad, LLC-Operation Exemption-Rail Line of Verde Logistics Railroad...

    Science.gov (United States)

    2012-03-08

    ... Logistics Railroad, LLC at Santa Teresa, Dona Ana County, NM Santa Teresa Southern Railroad, LLC (STSR), a... feet of rail line owned by Verde Logistics Railroad, LLC (Verde). The rail line extends between a point... to shippers and receivers located in the Santa Teresa Logistics Industrial Park. \\1\\ STSR states...

  3. 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

  4. Bio-Aerosol Detection Using Mass Spectrometry: Public Health Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ludvigson, L D

    2004-03-05

    I recently spent a summer as an intern at the Lawrence Livermore National Laboratory. I worked on a project involving the real-time, reagentless, single cell detection of aerosolized pathogens using a novel mass spectrometry approach called Bio-Aerosol Mass Spectrometry (BAMS). Based upon preliminary results showing the differentiation capabilities of BAMS, I would like to explore the development and use of this novel detection system in the context of both environmental and clinical sample pathogen detection. I would also like to explore the broader public health applications that a system such as BAMS might have in terms of infectious disease prevention and control. In order to appreciate the potential of this instrument, I will demonstrate the need for better pathogen detection methods, and outline the instrumentation, data analysis and preliminary results that lead me toward a desire to explore this technology further. I will also discuss potential experiments for the future along with possible problems that may be encountered along the way.

  5. Bio-Aerosol Detection Using Mass Spectrometry: Public Health Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ludvigson, Laura D. [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    I recently spent a summer as an intern at the Lawrence Livermore National Laboratory. I worked on a project involving the real-time, reagentless, single cell detection of aerosolized pathogens using a novel mass spectrometry approach called Bio-Aerosol Mass Spectrometry (BAMS). Based upon preliminary results showing the differentiation capabilities of BAMS, I would like to explore the development and use of this novel detection system in the context of both environmental and clinical sample pathogen detection. I would also like to explore the broader public health applications that a system such as BAMS might have in terms of infectious disease prevention and control. In order to appreciate the potential of this instrument, I will demonstrate the need for better pathogen detection methods, and outline the instrumentation, data analysis and preliminary results that lead me toward a desire to explore this technology further. I will also discuss potential experiments for the future along with possible problems that may be encountered along the way.

  6. Development and application of an aerosol screening model for size-resolved urban aerosols.

    Science.gov (United States)

    Stanier, Charles O; Lee, Sang-Rin

    2014-06-01

    Predictive models of vehicular ultrafine particles less than 0.1 microm in diameter (UFPs*) and other urban pollutants with high spatial and temporal variation are useful and important in applications such as (1) decision support for infrastructure projects, emissions controls, and transportation-mode shifts; (2) the interpretation and enhancement of observations (e.g., source apportionment, extrapolation, interpolation, and gap-filling in space and time); and (3) the generation of spatially and temporally resolved exposure estimates where monitoring is unfeasible. The objective of the current study was to develop, test, and apply the Aerosol Screening Model (ASM), a new physically based vehicular UFP model for use in near-road environments. The ASM simulates hourly average outdoor concentrations of roadway-derived aerosols and gases. Its distinguishing features include user-specified spatial resolution; use of the Weather Research and Forecasting (WRF) meteorologic model for winds estimates; use of a database of more than 100,000 road segments in the Los Angeles, California, region, including freeway ramps and local streets; and extensive testing against more than 9000 hours of observed particle concentrations at 11 sites. After initialization of air parcels at an upwind boundary, the model solves for vehicle emissions, dispersion, coagulation, and deposition using a Lagrangian modeling framework. The Lagrangian parcel of air is subdivided vertically (into 11 levels) and in the crosswind direction (into 3 parcels). It has overall dimensions of 10 m (downwind), 300 m (vertically), and 2.1 km (crosswind). The simulation is typically started 4 km upwind from the receptor, that is, the location at which the exposure is to be estimated. As parcels approach the receptor, depending on the user-specified resolution, step size is decreased, and crosswind resolution is enhanced through subdivision of parcels in the crosswind direction. Hourly concentrations and size

  7. Applications of the charged aerosol detector in compound management.

    Science.gov (United States)

    Sinclair, Ian; Charles, Isabel

    2009-06-01

    Recent literature has described the exciting development of a new universal detection technology for high-performance liquid chromatography (HPLC), as well as some exploratory work on its application to quantitative measurement of solutes at millimolar concentrations. The new methodology, known as charged aerosol detection (CAD), has been recognized as a viable alternative to evaporative light-scattering detection and refractive index detection that, like CAD, respond to molecular structures independently of their absorbance, or lack thereof, in the ultraviolet region of the electromagnetic spectrum. In this article, the authors exemplify their use of CAD in-line with HPLC and mass spectrometry (MS) to provide both stand-alone and complementary information that aids decision making for sample storage and processing practices in the compound management setting. Illustrations include monitoring contaminants leached from different plate materials into the solvent dimethyl sulphoxide (DMSO) and profiling the concentrations of solutions destined for liquid storage and dispensing to assays, with the aim of improving processes.

  8. Alienata da’ sensi: reframing Bernini’s S. Teresa

    Directory of Open Access Journals (Sweden)

    Andrea Bolland

    2015-02-01

    Full Text Available Gian Lorenzo Bernini’s Ecstasy of St Teresa for the Cornaro Chapel (1647–52 is perhaps the artist’s most sensually charged creation, and the apparently physical nature of Teresa’s ecstasy is today even acknowledged in survey textbooks. Teresa herself opened the door to this reading when, in describing her spiritual ecstasy, she admitted that ‘the body doesn’t fail to share in some of it, and even a great deal’. Yet the balance between sense and spirit in the sculpture emerges somewhat differently if it is viewed (literally and figuratively in context: as an altarpiece in a chapel where its presentation is structured as a ‘performance’, complete with spectators or witnesses, and as the central image of the left transept of Santa Maria della Vittoria – a church whose dedication derives from the power of the image (the Madonna della vittoria displayed above the main altar. If the statue group is read as a divine ecstasy witnessed, rather than a mystic encounter experienced, it engages another discourse, with its own metaphors and meanings. The saint’s swoon has less to do with the erotic capacity of the senses than with their absence, presenting a rather different challenge to an artist celebrated for his ability to transform insensate stone into vulnerable flesh.

  9. Application of the variability-size relationship to atmospheric aerosol studies: estimating aerosol lifetimes and ages

    Directory of Open Access Journals (Sweden)

    J. Williams

    2002-01-01

    Full Text Available Aerosol variability is examined as function of particle size for data collected over the Northern Indian Ocean in February 1999 as part of the INDOEX experiment. It was found that for particles believed to be of terrestrial or oceanic origin, the variability correlated with the average number concentration. For particles that are thought to be formed and grow in the atmosphere through coagulation and condensation an anticorrelation was observed, the minimum in variability coinciding with the maximum in the number concentration. Three altitude ranges were examined (0--1, 4--8 and 8--13 km and the minimum in variability was found to occur at lower particle sizes in the free troposphere (0.065 mm than in the boundary layer (0.165 mm. The observed variability has been compared to that generated by a numerical model in order to determine the relative importance of the physical processes. Modelled variability of 0.02 mm particles caused by nucleation was not observed in the measurements. A previously derived empirical relationship for aerosol residence time was compared with the measured variability as a function of bin size. The aerosol variability / residence time relationship was characterised by a coefficient (b at all altitudes and for both correlating and anticorrelating regimes. By combining the derived coefficient with the model predicted lifetime for 0.020 mm particles we estimated residence times and ages as a function of particle size and altitude. General agreement was found with previous estimates of aerosol residence time. In the upper atmosphere aerosols of 0.065 mm in size have residence times of approximately 1 month and can be transported on a hemispheric scale. The same size aerosol has a lifetime one order of magnitude less in the boundary layer and therefore will not be transported far from the source regions.

  10. Messa in estasi: sguardi sul corpo di Teresa

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    Elena Bonelli

    2010-06-01

    Full Text Available Elena Bonelli analiza, a través de elementos de semiótica, estética y gender criticism, el juego de miradas que se crea en la Iglesia de Santa Maria della Vittoria (Roma entre la estatua de Santa Teresa de G. Bernini, el simulacro de Santa Vittora, un icono de la Virgen María y los visitadores de la capilla romana. Según la autora, la disposición espacial de las tres figuras religiosas no sólo acentúa la curiosidad escópica de espectador situándole en el lugar de voyeur, sino que sugiere también una interesante lectura sobre los modos de inscripción del cuerpo femenino en el discurso artístico y, más en general, en toda la cultura occidental.

  11. Amor meus, Cruxifixus est! / Teresa Perciaccante ; tõlk. Anne Kalling

    Index Scriptorium Estoniae

    Perciaccante, Teresa

    2002-01-01

    Kevadisest kriisist Petlemmas, mil Iisraeli armee piiras Jeesus Kristuse sünnikirikut. Ema Teresa Perciaccante kiri Pühima Päästja Püha Birgitta ordu ülemaabtissile Ema Tekla Famigliettile Rooma

  12. St. Teresa van Avila: sentrale figuur in die werk van Cussons en Van Wyk Louw

    Directory of Open Access Journals (Sweden)

    H. van Vuuren

    1989-05-01

    Full Text Available A central poem in Van Wyk Louw’s Tristia (1962, is “H. Teresa van Avila flap uit” (literally translated: “Saint Teresa of Avila talks too much/babbles uncontrollably”. This article illustrates how intertextual reading helped to clarify the poem. Teresa of Avila’s The way of perfection (a translation of the Spanish work El Camino de la Perfección, 1573 is the intertext of the Van Wyk Louw poem. In the last section of the article it is shown how the figure of St. Teresa of Avila is central not only to Van Wyk Louw’s Tristia (1962, but also to the oeuvre of Sheila Cussons, which underlines a strong intertextuality between these two Afrikaans oeuvres.

  13. An Evaluation of Aerosol Extinguishing Systems for Machinery Space Applications

    Science.gov (United States)

    2006-02-01

    MSC/Cir. 1007) “Guidelines for the Approval of Fixed Aerosol Fire-Extinguishing Systems Equivalent to Fixed Gas Fire -Extinguishing Systems...Committee/Circular (MSC/Circ.) 1007 “Guidelines for the Approval of Fixed Aerosol Fire-Extinguishing Systems Equivalent to Fixed Gas Fire -Extinguishing...combustibles in machinery spaces. This test is also required in the approval of both halocarbon and inert gas fire extinguishing systems. These issues

  14. Updated aerosol module and its application to simulate secondary organic aerosols during IMPACT campaign May 2008

    Directory of Open Access Journals (Sweden)

    Y. P. Li

    2013-03-01

    Full Text Available The formation of Secondary organic aerosol (SOA was simulated with the Secondary ORGanic Aerosol Model (SORGAM by a classical gas-particle partitioning concept, using the two-product model approach, which is widely used in chemical transport models. In this study, we extensively updated SORGAM including three major modifications: firstly, we derived temperature dependence functions of the SOA yields for aromatics and biogenic VOCs, based on recent chamber studies within a sophisticated mathematic optimization framework; secondly, we implemented the SOA formation pathways from photo oxidation (OH initiated of isoprene; thirdly, we implemented the SOA formation channel from NO3-initiated oxidation of reactive biogenic hydrocarbons (isoprene and monoterpenes. The temperature dependence functions of the SOA yields were validated against available chamber experiments. Moreover, the whole updated SORGAM module was validated against ambient SOA observations represented by the summed oxygenated organic aerosol (OOA concentrations abstracted from Aerosol Mass Spectrometer (AMS measurements at a rural site near Rotterdam, the Netherlands, performed during the IMPACT campaign in May 2008. In this case, we embedded both the original and the updated SORGAM module into the EURopean Air pollution and Dispersion-Inverse Model (EURAD-IM, which showed general good agreements with the observed meteorological parameters and several secondary products such as O3, sulfate and nitrate. With the updated SORGAM module, the EURAD-IM model also captured the observed SOA concentrations reasonably well especially those during nighttime. In contrast, the EURAD-IM model before update underestimated the observations by a factor of up to 5. The large improvements of the modeled SOA concentrations by updated SORGAM were attributed to the mentioned three modifications. Embedding the temperature dependence functions of the SOA yields, including the new pathways from isoprene photo

  15. Updated aerosol module and its application to simulate secondary organic aerosols during IMPACT campaign May 2008

    Science.gov (United States)

    Li, Y. P.; Elbern, H.; Lu, K. D.; Friese, E.; Kiendler-Scharr, A.; Mentel, Th. F.; Wang, X. S.; Wahner, A.; Zhang, Y. H.

    2013-07-01

    The formation of Secondary organic aerosol (SOA) was simulated with the Secondary ORGanic Aerosol Model (SORGAM) by a classical gas-particle partitioning concept, using the two-product model approach, which is widely used in chemical transport models. In this study, we extensively updated SORGAM including three major modifications: firstly, we derived temperature dependence functions of the SOA yields for aromatics and biogenic VOCs (volatile organic compounds), based on recent chamber studies within a sophisticated mathematic optimization framework; secondly, we implemented the SOA formation pathways from photo oxidation (OH initiated) of isoprene; thirdly, we implemented the SOA formation channel from NO3-initiated oxidation of reactive biogenic hydrocarbons (isoprene and monoterpenes). The temperature dependence functions of the SOA yields were validated against available chamber experiments, and the updated SORGAM with temperature dependence functions was evaluated with the chamber data. Good performance was found with the normalized mean error of less than 30%. Moreover, the whole updated SORGAM module was validated against ambient SOA observations represented by the summed oxygenated organic aerosol (OOA) concentrations abstracted from aerosol mass spectrometer (AMS) measurements at a rural site near Rotterdam, the Netherlands, performed during the IMPACT campaign in May 2008. In this case, we embedded both the original and the updated SORGAM module into the EURopean Air pollution and Dispersion-Inverse Model (EURAD-IM), which showed general good agreements with the observed meteorological parameters and several secondary products such as O3, sulfate and nitrate. With the updated SORGAM module, the EURAD-IM model also captured the observed SOA concentrations reasonably well especially those during nighttime. In contrast, the EURAD-IM model before update underestimated the observations by a factor of up to 5. The large improvements of the modeled SOA

  16. Updated aerosol module and its application to simulate secondary organic aerosols during IMPACT campaign May 2008

    Directory of Open Access Journals (Sweden)

    Y. P. Li

    2013-07-01

    Full Text Available The formation of Secondary organic aerosol (SOA was simulated with the Secondary ORGanic Aerosol Model (SORGAM by a classical gas-particle partitioning concept, using the two-product model approach, which is widely used in chemical transport models. In this study, we extensively updated SORGAM including three major modifications: firstly, we derived temperature dependence functions of the SOA yields for aromatics and biogenic VOCs (volatile organic compounds, based on recent chamber studies within a sophisticated mathematic optimization framework; secondly, we implemented the SOA formation pathways from photo oxidation (OH initiated of isoprene; thirdly, we implemented the SOA formation channel from NO3-initiated oxidation of reactive biogenic hydrocarbons (isoprene and monoterpenes. The temperature dependence functions of the SOA yields were validated against available chamber experiments, and the updated SORGAM with temperature dependence functions was evaluated with the chamber data. Good performance was found with the normalized mean error of less than 30%. Moreover, the whole updated SORGAM module was validated against ambient SOA observations represented by the summed oxygenated organic aerosol (OOA concentrations abstracted from aerosol mass spectrometer (AMS measurements at a rural site near Rotterdam, the Netherlands, performed during the IMPACT campaign in May 2008. In this case, we embedded both the original and the updated SORGAM module into the EURopean Air pollution and Dispersion-Inverse Model (EURAD-IM, which showed general good agreements with the observed meteorological parameters and several secondary products such as O3, sulfate and nitrate. With the updated SORGAM module, the EURAD-IM model also captured the observed SOA concentrations reasonably well especially those during nighttime. In contrast, the EURAD-IM model before update underestimated the observations by a factor of up to 5. The large improvements of the modeled

  17. Scanning Transmission X-ray Microscopy: Applications in Atmospheric Aerosol Research

    Energy Technology Data Exchange (ETDEWEB)

    Moffet, Ryan C.; Tivanski, Alexei V.; Gilles, Mary K.

    2011-01-20

    Scanning transmission x-ray microscopy (STXM) combines x-ray microscopy and near edge x-ray absorption fine structure spectroscopy (NEXAFS). This combination provides spatially resolved bonding and oxidation state information. While there are reviews relevant to STXM/NEXAFS applications in other environmental fields (and magnetic materials) this chapter focuses on atmospheric aerosols. It provides an introduction to this technique in a manner approachable to non-experts. It begins with relevant background information on synchrotron radiation sources and a description of NEXAFS spectroscopy. The bulk of the chapter provides a survey of STXM/NEXAFS aerosol studies and is organized according to the type of aerosol investigated. The purpose is to illustrate the current range and recent growth of scientific investigations employing STXM-NEXAFS to probe atmospheric aerosol morphology, surface coatings, mixing states, and atmospheric processing.

  18. Agency and Otherness in Teresa Margolles’ Aesthetic of Death

    Directory of Open Access Journals (Sweden)

    Julia Banwell

    2010-10-01

    Full Text Available Teresa Margolles (b. 1963 is Mexico's foremost proponent of corpse art. Her work meditates upon her obsessions with the dead body and the processes that occur after death, and shows death as a direct result of violence. Employing a range of techniques of representation, Margolles implicates the spectator into potentially uncomfortably close contemplation of the artwork, sometimes through direct physical contact with the raw materials used in its creation. She transgresses the boundaries between the interior and the exterior of the body, and between life and death, occupying an artistic space where the minimalist and internationally accessible language of conceptual art interacts with her method of commenting upon a specifically Mexican set of circumstances, at times disguising unsettling realities behind deceptively subtle artistic techniques of representation. Drawing on theories of spectatorship and the problematics of looking at death, this essay will explore aspects of agency, eroticism and otherness in examples of Margolles' artwork, also paying attention to the question of ethics. The bodies and body parts the artist places at the centre of her works, witness the unsettlingly direct relation between violence enacted upon the body, and its result, death. The removal of these physical entities from social space leaves behind traces and residues that now, by means of the artist's intervention, metonymically evidence their former lives and erase the distance between dead and living bodies.

  19. Teresa Urrea: Mexican mystic, healer, and apocalyptic revolutionary.

    Science.gov (United States)

    Nava, Alex

    2005-01-01

    This article is a study of the mystical and apocalyptic dimensions of Teresa Urrea. As explained in this article, Urrea’s mystical experiences and visions are unique for their connection with a propheticapocalyptic and political worldview. This apocalyptic dimension is more than a communication of a hidden message or spiritual world; it also includes a reading of history that is catastrophic and discontinuous. The crisis and terror of history are given expression in Urrea’s mystical and apocalyptic pronouncements. In particular, the chaotic and oppressive circumstances of Mexican society during the dictatorship of Porfirio Diaz was confronted and denounced in Urrea’s mystical and apocalyptic ministry. This apocalyptic healer castigated those culpable or even complicit with the injustices affecting the indigenous communities of Mexico during the late nineteenth century. In the case of Urrea, the transformation and healing of Church and society was an important aspect of her spiritual, healing powers. Because Urrea possessed neither arms nor the weapon of the pen, her sole weapon became her mystical experiences and the insight and healing powers that flowed from them. People of Mexico—especially indigenous groups—began to flock to her hoping that she would bring God’s presence to the troubled and chaotic circumstances of their lives. Her compassion and tenderness for the afflicted as well as the apocalyptic expectations that she stirred up among the indigenous groups of Northern Mexico were enough to get this mystical-political Mexican mestiza exiled from her homeland.

  20. MODIS 3 km aerosol product: applications over land in an urban/suburban region

    Directory of Open Access Journals (Sweden)

    L. A. Munchak

    2013-02-01

    Full Text Available MODerate resolution Imaging Spectroradiometer (MODIS instruments aboard the Terra and Aqua satellites have provided a rich dataset of aerosol information at a 10 km spatial scale. Although originally intended for climate applications, the air quality community quickly became interested in using the MODIS aerosol data. However, 10 km resolution is not sufficient to resolve local scale aerosol features. With this in mind, MODIS Collection 6 is including a global aerosol product with a 3 km resolution. Here, we evaluate the 3 km product over the Baltimore/Washington D.C., USA, corridor during the summer of 2011, by comparing with spatially dense data collected as part of the DISCOVER-AQ campaign; these data were measured by the NASA Langley Research Center airborne High Spectral Resolution Lidar (HSRL and a network of 44 sun photometers (SP spaced approximately 10 km apart. The HSRL instrument shows that AOD can vary by up to 0.2 within a single 10 km MODIS pixel, meaning that higher resolution satellite retrievals may help to characterize aerosol spatial distributions in this region. Different techniques for validating a high-resolution aerosol product against SP measurements are considered. Although the 10 km product is more statistically reliable than the 3 km product, the 3 km product still performs acceptably, with more than two-thirds of MODIS/SP collocations falling within the expected error envelope with high correlation (R > 0.90. The 3 km product can better resolve aerosol gradients and retrieve closer to clouds and shorelines than the 10 km product, but tends to show more significant noise especially in urban areas. This urban degradation is quantified using ancillary land cover data. Overall, we show that the MODIS 3 km product adds new information to the existing set of satellite derived aerosol products and validates well over the region, but due to noise and problems in urban areas, should be treated with some degree of

  1. Development and Applications of a New, High-Resolution, Operational MISR Aerosol Product

    Science.gov (United States)

    Garay, M. J.; Diner, D. J.; Kalashnikova, O.

    2014-12-01

    Since early 2000, the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite has been providing aerosol optical depth (AOD) and particle property retrievals at 17.6 km spatial resolution. Capitalizing on the capabilities provided by multi-angle viewing, the operational MISR algorithm performs well, with about 75% of MISR AOD retrievals falling within 0.05 or 20% × AOD of the paired validation data from the ground-based Aerosol Robotic Network (AERONET), and is able to distinguish aerosol particles by size and sphericity, over both land and water. These attributes enable a variety of applications, including aerosol transport model validation and global air quality assessment. Motivated by the adverse impacts of aerosols on human health at the local level, and taking advantage of computational speed advances that have occurred since the launch of Terra, we have implemented an operational MISR aerosol product with 4.4 km spatial resolution that maintains, and sometimes improves upon, the quality of the 17.6 km resolution product. We will describe the performance of this product relative to the heritage 17.6 km product, the global AERONET validation network, and high spatial density AERONET-DRAGON sites. Other changes that simplify product content, and make working with the data much easier for users, will also be discussed. Examples of how the new product demonstrates finer spatial variability of aerosol fields than previously retrieved, and ways this new dataset can be used for studies of local aerosol effects, will be shown.

  2. MODIS 3 Km Aerosol Product: Applications over Land in an Urban/suburban Region

    Science.gov (United States)

    Munchak, L. A.; Levy, R. C.; Mattoo, S.; Remer, L. A.; Holben, B. N.; Schafer, J. S.; Hostetler, C. A.; Ferrare, R. A.

    2013-01-01

    MODerate resolution Imaging Spectroradiometer (MODIS) instruments aboard the Terra and Aqua satellites have provided a rich dataset of aerosol information at a 10 km spatial scale. Although originally intended for climate applications, the air quality community quickly became interested in using the MODIS aerosol data. However, 10 km resolution is not sufficient to resolve local scale aerosol features. With this in mind, MODIS Collection 6 is including a global aerosol product with a 3 km resolution. Here, we evaluate the 3 km product over the Baltimore/Washington D.C., USA, corridor during the summer of 2011, by comparing with spatially dense data collected as part of the DISCOVER-AQ campaign these data were measured by the NASA Langley Research Center airborne High Spectral Resolution Lidar (HSRL) and a network of 44 sun photometers (SP) spaced approximately 10 km apart. The HSRL instrument shows that AOD can vary by up to 0.2 within a single 10 km MODIS pixel, meaning that higher resolution satellite retrievals may help to characterize aerosol spatial distributions in this region. Different techniques for validating a high-resolution aerosol product against SP measurements are considered. Although the 10 km product is more statistically reliable than the 3 km product, the 3 km product still performs acceptably, with more than two-thirds of MODIS/SP collocations falling within the expected error envelope with high correlation (R > 0.90). The 3 km product can better resolve aerosol gradients and retrieve closer to clouds and shorelines than the 10 km product, but tends to show more significant noise especially in urban areas. This urban degradation is quantified using ancillary land cover data. Overall, we show that the MODIS 3 km product adds new information to the existing set of satellite derived aerosol products and validates well over the region, but due to noise and problems in urban areas, should be treated with some degree of caution.

  3. The Unio Mystica of Teresa of Avila: two classical presentations in the light of psychology

    Directory of Open Access Journals (Sweden)

    Hans Åkerberg

    1982-01-01

    Full Text Available It is generally maintained within the Carmelite tradition that Teresa (1515-1582 showed an extraordinary facility in describing the stages of mysticism with experimential vigour and deep intensity, compared for example to John of the Cross, whose mystical presentation is of a more dogmatic and systematic nature. In this sense she would appear to be unsurpassed within the entire Roman Catholic mystic tradition. The author compares two classical presentations by Teresa of the significance of unio mystica, firstly her description of this in the Libro de la vida, and secondly her presentation of the same mystic element in the book Castillo interior o Las moradas.

  4. The spiritual quest in “Los tres cantos” by Teresa Wilms Montt

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    Gabriela Jerez Garcés

    2015-04-01

    Full Text Available Analysis of the text “Los tres cantos” (1917 of the chilean writer Teresa Wilms Montt, understanding it as an exercise of spiritual search from the interior of the language, in which the poetry recovers her possibilities of extension of the spiritual conscience. The text is framed at the beginning of the vanguard will, which starts germinating in Chile about 1910, year in which there appears a trend named spiritualism of vanguard, aesthetic current based on the idea of that the spiritual life and experience of the soul constitute the axis of the human transcendence.Key words: Chilean Poetry, Teresa Wilms, spiritualism, vanguard.

  5. Wright, Teresa, Accepting Authoritarianism: State-society Relations in China’s Reform Era

    OpenAIRE

    Friedman, Edward

    2011-01-01

    Wright, Teresa, Accepting Authoritarianism: State-society Relations in China’s Reform Era, Stanford, Stanford UP, 2010, 254 pp. Teresa Wright contends that all China’s diverse economic strata succeed by relying on the state. Therefore, they are not about to turn against their government. They “accept” the CCP because of how late industrialisation, state-led development, and socialist legacies combine to shape opinion. Wright’s choice of strata leads to a vision of China as half an onion, with...

  6. Development of the Ensemble Navy Aerosol Analysis Prediction System (ENAAPS) and its application of the Data Assimilation Research Testbed (DART) in support of aerosol forecasting

    Science.gov (United States)

    Rubin, Juli I.; Reid, Jeffrey S.; Hansen, James A.; Anderson, Jeffrey L.; Collins, Nancy; Hoar, Timothy J.; Hogan, Timothy; Lynch, Peng; McLay, Justin; Reynolds, Carolyn A.; Sessions, Walter R.; Westphal, Douglas L.; Zhang, Jianglong

    2016-03-01

    An ensemble-based forecast and data assimilation system has been developed for use in Navy aerosol forecasting. The system makes use of an ensemble of the Navy Aerosol Analysis Prediction System (ENAAPS) at 1 × 1°, combined with an ensemble adjustment Kalman filter from NCAR's Data Assimilation Research Testbed (DART). The base ENAAPS-DART system discussed in this work utilizes the Navy Operational Global Analysis Prediction System (NOGAPS) meteorological ensemble to drive offline NAAPS simulations coupled with the DART ensemble Kalman filter architecture to assimilate bias-corrected MODIS aerosol optical thickness (AOT) retrievals. This work outlines the optimization of the 20-member ensemble system, including consideration of meteorology and source-perturbed ensemble members as well as covariance inflation. Additional tests with 80 meteorological and source members were also performed. An important finding of this work is that an adaptive covariance inflation method, which has not been previously tested for aerosol applications, was found to perform better than a temporally and spatially constant covariance inflation. Problems were identified with the constant inflation in regions with limited observational coverage. The second major finding of this work is that combined meteorology and aerosol source ensembles are superior to either in isolation and that both are necessary to produce a robust system with sufficient spread in the ensemble members as well as realistic correlation fields for spreading observational information. The inclusion of aerosol source ensembles improves correlation fields for large aerosol source regions, such as smoke and dust in Africa, by statistically separating freshly emitted from transported aerosol species. However, the source ensembles have limited efficacy during long-range transport. Conversely, the meteorological ensemble generates sufficient spread at the synoptic scale to enable observational impact through the ensemble data

  7. Evaluation and application of passive and active optical remote sensing methods for the measurement of atmospheric aerosol properties

    Energy Technology Data Exchange (ETDEWEB)

    Mielonen, T.

    2010-07-01

    assumptions and more realistic assumptions improve the retrieved parameters. However, other derived parameters, i.e. aerosol optical depth may deteriorate. In additio, the possibility to improve aerosol typing based on active spaceborne measurements by adding an additional parameter into the retrieval was studied. Unfortunately, the available parameter (color ratio) did not bring additional information into the retrieval. For the application part, remote sensed data was used in the estimation of particulate matter at the surface and in the analysis of seasonal profiles of vertical properties. The studies in this thesis show that optical remote sensing can give invaluable information on the properties of atmospheric aerosols. However, the retrieval of aerosol properties with undetermined information content is an extremely difficult task. Thus, the user should be aware of the uncertainties and the error sources in the retrieved parameters. (orig.)

  8. New spectral methods in cloud and aerosol remote sensing applications

    Science.gov (United States)

    Schmidt, K. Sebastian; McBride, Patrick; Pilewskie, Peter; Feingold, Graham; Jiang, Hongli

    2010-05-01

    We present new remote sensing techniques that rely on spectral observations of clouds and aerosols in the solar wavelength range. As a first example, we show how the effects of heterogeneous clouds, aerosols of changing optical properties, and the surface within one pixel can be distinguished by means of their spectral signatures. This example is based on data from the Gulf of Mexico Atmospheric Composition and Climate Study (GoMACCS, Houston, Texas, 2006), Large Eddy Simulations (LES) of polluted boundary layer clouds, and 3-dimensional radiative transfer calculations. In a second example, we show that the uncertainty of cloud retrievals can be improved considerably by exploiting the spectral information around liquid water absorption features in the near-infrared wavelength range. This is illustrated with spectral transmittance data from the NOAA International Chemistry Experiment in the Arctic LOwer Troposphere (ICEALOT, 2008). In contrast to reflected radiance, transmitted radiance is only weakly sensitive to cloud effective drop radius, and only cloud optical thickness can be obtained from the standard dual-channel technique. We show that effective radius and liquid water path can also be retrieved with the new spectral approach, and validate our results with microwave liquid water path measurements.

  9. Measurement of the ambient organic aerosol volatility distribution: application during the Finokalia Aerosol Measurement Experiment (FAME-2008

    Directory of Open Access Journals (Sweden)

    B. H. Lee

    2010-12-01

    Full Text Available A variable residence time thermodenuder (TD was combined with an Aerodyne Aerosol Mass Spectrometer (AMS and a Scanning Mobility Particle Sizer (SMPS to measure the volatility distribution of aged organic aerosol in the Eastern Mediterranean during the Finokalia Aerosol Measurement Experiment in May of 2008 (FAME-2008. A new method for the quantification of the organic aerosol volatility distribution was developed combining measurements of all three instruments together with an aerosol dynamics model.

    Challenges in the interpretation of ambient thermodenuder-AMS measurements include the potential resistances to mass transfer during particle evaporation, the effects of particle size on the evaporated mass fraction, the changes in the AMS collection efficiency and particle density as the particles evaporate partially in the TD, and finally potential losses inside the TD. Our proposed measurement and data analysis method accounts for all of these problems combining the AMS and SMPS measurements.

    The AMS collection efficiency of the aerosol that passed through the TD was found to be approximately 10% lower than the collection efficiency of the aerosol that passed through the bypass. The organic aerosol measured at Finokalia is approximately 2 or more orders of magnitude less volatile than fresh laboratory-generated monoterpene (α-pinene, β-pinene and limonene under low NOx conditions secondary organic aerosol. This low volatility is consistent with its highly oxygenated AMS mass spectrum. The results are found to be highly sensitive to the mass accommodation coefficient of the evaporating species. This analysis is based on the assumption that there were no significant reactions taking place inside the thermodenuder.

  10. La dualidad de Teresa de Jesús y el proyecto de “Jesuitas descalzos”

    Directory of Open Access Journals (Sweden)

    Rodríguez-San Pedro Bezares, Luis E.

    2016-06-01

    Full Text Available A duality based on her personality and her project coexisted in Teresa of Jesus. This duality is the origin of the later evolution (and misunderstandings of the Order of Discalced Carmelite; especially in the male section. From Teresa as a hermit, who is introspective and nostalgic for the primitive Rule, to the active founder woman concerned about the missions and the salvation of souls. Juan de la Cruz would be placed in the wake of the “first Teresa” and Jerónimo Gracián in the “second one”. In this regard, two possible ways of Carmelo lived together in the life of Teresa of Jesus, but much creativity, inner plurality and energy were not available to everyone. The understanding between “the second Teresa” and Jerónimo Gracián, did it not promote a tendency in Discalced Carmelites that we could call “Discalced Jesuits”? In other words: apostolic/missionaries and contemplative/penitents at the same time.En Teresa de Jesús parece coexistir una dualidad personal y de proyecto, que está en el origen de la evolución posterior (y los desencuentros de la Orden Carmelita Descalza; sobre todo en la rama masculina. Desde la Teresa ermitaña, interior y añorante de la Regla primitiva, a la activa fundadora con preocupación misional y salvación de almas. Juan de la Cruz se situaría en la estela de “la primera Teresa”, y Jerónimo Gracián en la de “la segunda”. En la vida de la propia Teresa de Jesús convivieron dos formas posibles de Carmelo; pero tanta creatividad, pluralidad interior y energía no estaba al alcance de todos. La sintonía entre “la segunda Teresa” y Jerónimo Gracián, ¿no propiciaba una tendencia de los Carmelitas descalzos que pudiéramos denominar de “Jesuitas descalzos”?: es decir, al tiempo apostólico/misioneros y contemplativo/penitentes.

  11. The application of an improved gas and aerosol collector for ambient air pollutants in China

    Science.gov (United States)

    Dong, Huabin; Zeng, Limin; Zhang, Yuanhang; Hu, Min; Wu, Yusheng

    2016-04-01

    An improved Gas and Aerosol Collector (GAC) equipped with a newly designed aerosol collector and a set of dull-polished wet annular denuder (WAD) was developed by Peking University based on a Steam Jet Aerosol Collector (SJAC) sampler. Combined with Ion Chromatography (IC) the new sampler performed well in laboratory tests with high collection efficiencies for SO2 (above 98 %) and particulate sulfate (as high as 99.5 %). An inter-comparison between the GAC-IC system and the filter-pack method was performed and the results indicated that the GAC-IC system could supply reliable particulate sulfate, nitrate, chloride, and ammonium data in field measurement with a much wider range of ambient concentrations. From 2008 to 2015, dozens of big field campaigns (rural and coastal sites) were executed in different parts of China, the GAC-IC system took the chance having its field measurement performance checked repeatedly and provided high quality data in ambient conditions either under high loadings of pollutants or background area. Its measurements were highly correlated with data by other commercial instruments such as the SO2 analyzer, the HONO analyzer, a filter sampler, Aerosol Mass Spectrometer (AMS), etc. over a wide range of concentrations and proved particularly useful in future intensive campaigns or long-term monitoring stations to study various environmental issues such as secondary aerosol and haze formation. During these years of applications of GAC-IC in those field campaigns, we found some problems of several instruments running under field environment and some interesting results could also be drew from the large amount of data measured in near 20 provinces of China. Detail results will be demonstrated on the poster afterwards.

  12. Paisajes para Teresa Andrés, bibliotecaria en tiempos de guerra (1936-1938

    Directory of Open Access Journals (Sweden)

    Salaberria Lizarazu, Ramón

    2010-12-01

    Full Text Available El presente artículo quiere centrarse en la actividad bibliotecaria de Teresa Andrés Zamora (1907-1946 durante el tiempo que transcurre entre la sublevación militar de julio de 1936 y el segundo semestre de 1938, en que se desmantela la Sección de Bibliotecas del Consejo Central de Archivos, Bibliotecas y Tesoro Artístico. En ese período Teresa Andrés va a ejercer como responsable de bibliotecas de Cultura Popular y toma parte destacada en la Comisión Gestora del Cuerpo Facultativo de Archivos, Bibliotecas y Museos y en la Sección de Bibliotecas del Consejo Central de Archivos, Bibliotecas y Tesoro Artístico.

  13. Love from attitudes of two Muslim and Christian mystics (Rabia Adaviye and Teresa Avila

    Directory of Open Access Journals (Sweden)

    Dr. Maryam Bakhtyar

    2013-06-01

    Full Text Available Love is an affection which is the extreme and peak. In this extreme love, lover (mystic loves his/her beloved (God with all of his/her own and he/she burns in his parting, mystical lover in fact will survive with the destruction (join to lover in true lover. Love of God is essential issue in Rabia Adaviye and Teresa Avila works. Rabia believes that in the bond of true love must be absolutely no contamination as a lover not ask for reward in turn his/her love not even waiting for an answer to his/her love. Also Teresa believes that original love is only for God and all loves along this love are justified and interpreted. Other friendships should not be an obstacle in the way God’s love or their ending should lead to divine love.

  14. COBRA: A Computational Brewing Application for Predicting the Molecular Composition of Organic Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Fooshee, David R.; Nguyen, Tran B.; Nizkorodov, Sergey A.; Laskin, Julia; Laskin, Alexander; Baldi, Pierre

    2012-05-08

    Atmospheric organic aerosols (OA) represent a significant fraction of airborne particulate matter and can impact climate, visibility, and human health. These mixtures are difficult to characterize experimentally due to the enormous complexity and dynamic nature of their chemical composition. We introduce a novel Computational Brewing Application (COBRA) and apply it to modeling oligomerization chemistry stemming from condensation and addition reactions of monomers pertinent to secondary organic aerosol (SOA) formed by photooxidation of isoprene. COBRA uses two lists as input: a list of chemical structures comprising the molecular starting pool, and a list of rules defining potential reactions between molecules. Reactions are performed iteratively, with products of all previous iterations serving as reactants for the next one. The simulation generated thousands of molecular structures in the mass range of 120-500 Da, and correctly predicted ~70% of the individual SOA constituents observed by high-resolution mass spectrometry (HR-MS). Selected predicted structures were confirmed with tandem mass spectrometry. Esterification and hemiacetal formation reactions were shown to play the most significant role in oligomer formation, whereas aldol condensation was shown to be insignificant. COBRA is not limited to atmospheric aerosol chemistry, but is broadly applicable to the prediction of reaction products in other complex mixtures for which reasonable reaction mechanisms and seed molecules can be supplied by experimental or theoretical methods.

  15. Development studies towards an 11-year global gridded aerosol optical thickness reanalysis for climate and applied applications

    Science.gov (United States)

    Lynch, P.; Reid, J. S.; Westphal, D. L.; Zhang, J.; Hogan, T. F.; Hyer, E. J.; Curtis, C. A.; Hegg, D. A.; Shi, Y.; Campbell, J. R.; Rubin, J. I.; Sessions, W. R.; Turk, F. J.; Walker, A. L.

    2015-12-01

    While standalone satellite and model aerosol products see wide utilization, there is a significant need in numerous climate and applied applications for a fused product on a regular grid. Aerosol data assimilation is an operational reality at numerous centers, and like meteorological reanalyses, aerosol reanalyses will see significant use in the near future. Here we present a standardized 2003-2013 global 1° × 1° and 6 hourly modal aerosol optical thickness (AOT) reanalysis product. This dataset can be applied to basic and applied earth system science studies of significant aerosol events, aerosol impacts on numerical weather prediction, and electro-optical propagation and sensor performance, among other uses. This paper describes the science of how to develop and score an aerosol reanalysis product. This reanalysis utilizes a modified Navy Aerosol Analysis and Prediction System (NAAPS) at its core and assimilates quality controlled retrievals of AOT from the Moderate Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua and the Multi-angle Imaging SpectroRadiometer (MISR) on Terra. The aerosol source functions, including dust and smoke, were regionally tuned to obtain the best match between the model fine and coarse mode AOTs and the Aerosol Robotic Network (AERONET) AOTs. Other model processes, including deposition, were tuned to minimize the AOT difference between the model and satellite AOT. Aerosol wet deposition in the tropics is driven with satellite retrieved precipitation, rather than the model field. The final reanalyzed fine and coarse mode AOT at 550 nm is shown to have good agreement with AERONET observations, with global mean root mean square error around 0.1 for both fine and coarse mode AOTs. This paper includes a discussion of issues particular to aerosol reanalyses that make them distinct from standard meteorological reanalyses, considerations for extending such a reanalysis outside of the NASA A-Train era, and examples of how the

  16. Time and times in the work of Saint Teresa of Avila: a narratological approach

    Directory of Open Access Journals (Sweden)

    Tomaž Šmid

    2012-12-01

    Full Text Available Time as a narrative category arises from the temporary status of any narrative by which the narrative language is oriented towards processes that are based on temporality. Time thus becomes one of the fundamental aspects of any narrative. Although the style of Teresa’s texts is characterised by the tone of oral conversation, this does not exclude her concern with the form and organisation of her writings. Our main concern is time from two different perspectives; on the one hand, as a component of the story and on the other, as its manifestation on the level of discourse. First, we analyse the relationships and the discrepancies in the works of St. Teresa of Avila between the discourse time and the story time, using three parameters: order, duration and frequency (Genette, 1972. Secondly, we examine different kinds of narration in the works of Saint Teresa to establish whether the majority of them are subsequent (ulterior, prior (anterior, simultaneous or interpolated (intercalated. Contrasting story time and discourse time in the works of Saint Teresa, we note the agility of her literary style and her ability to organize narrative syntax.

  17. Hooglied, liggaam en die mistikus, Sint Teresa van Avila (1515–1582

    Directory of Open Access Journals (Sweden)

    H. Viviers

    2002-11-01

    Full Text Available Song of Songs, body and the mystic, St Teresa of Avila (1515 – 1582In this article the interaction between an allegorical (tropological understanding of the Song of Songs, the body and the internalized societal values of the sixteenth century Spanish mystic, St Teresa of Avila will be highlighted. Our bodies are central in our symbolizing activities and this confirms that we are (animated bodies. St Teresa cannot escape her body, not even in the elevated spiritual state of the unio mystica, utilizing the words of love in the Song to voice the soul’s glowing love for Christ. The body’s “voice” is always present, in spite of her societal dualistic values of prioritising the spirit at the expense of the body and it even subtly enhances self-realisation. The repressed body always returns. The “text” of the body onto which is “written” societal values becomes an important source of exposing a society’s hidden ideologies.

  18. Emulsions, foams, suspensions, and aerosols microscience and applications

    CERN Document Server

    Schramm, Laurier L

    2014-01-01

    This is the first book to provide an integrated introduction to the nature, formation and occurrence, stability, propagation, and uses of the most common types of colloidal dispersion in the process-related industries. The primary focus is on the applications of the principles, paying attention to practical processes and problems. This is done both as part of the treatment of the fundamentals, where appropriate, and also in the separate sections devoted to specifi c kinds of industries. Throughout, the treatment is integrated, with the principles of colloid and interface science common to each

  19. A Amazônia e a floresta, de Teresa Isenburg L’Amazonie et la forêt, par Teresa Isenburg The Amazon and the forest, by Teresa Isenburg

    Directory of Open Access Journals (Sweden)

    Andrea Cavicchioli

    2012-11-01

    Full Text Available Essa leitura do novo livro, em italiano, de Teresa Isenburg L’Amazzonia e la foresta (A Amazônia e a floresta pode começar pela reprodução de um dos muitos e preciosos comentários contidos em notas de rodapé. Na página 72, está dito:Frigoríficos [em português no original] – Desconheço a palavra italiana equivalente para definir esse segmento da linha de produção da carne que gerencia a passagem do criador ao vendedor para o consumo e que incorpora na denominação portuguesa, parecida com a es...

  20. Atmospheric aerosol dispersion models and their applications to environmental risk assessment

    Directory of Open Access Journals (Sweden)

    Andrzej Mazur

    2014-03-01

    Full Text Available Introduction. Numerical models of dispersion of atmospheric pollutants are widely used to forecast the spread of contaminants in the air and to analyze the effects of this phenomenon. The aim of the study is to investigate the possibilities and the quality of diagnosis and prediction of atmospheric transport of aerosols in the air using the dispersion model of atmospheric pollutants, developed at the Institute of Meteorology and Water Management (IMWM in Warsaw. Material and methods. A model of the dispersion of atmospheric pollutants, linked with meteorological models in a diagnostic mode, was used to simulate the transport of the cloud of aerosols released during the crash near the town of Ożydiw (Ukraine and of volcanic ash – during the volcanic eruption of Eyjafjallajökull in Iceland. Results. Possible directions of dispersion of pollutants in the air and its concentration in the atmosphere and deposition to the soil were assessed. The analysis of temporal variability of concentrations of aerosols in the atmosphere confirmed that the model developed at IMWM is an effective tool for diagnosis of air quality in the area of Poland as well as for determination of exposure duration to the aerosol clouds for different weather scenarios. Conclusions. The results are a confirmation of the thesis, that because in the environmental risk assessment, an important element is not only current information on the level of pollution concentrations, but also the time of exposure to pollution and forecast of these elements, and consequently the predicted effects on man or the environment in general; so it is necessary to use forecasting tools, similar to presented application. The dispersion model described in the paper is an operational tool for description, analysis and forecasting of emergency situations in case of emissions of hazardous substances.

  1. Aerosolized Antibiotics.

    Science.gov (United States)

    Restrepo, Marcos I; Keyt, Holly; Reyes, Luis F

    2015-06-01

    Administration of medications via aerosolization is potentially an ideal strategy to treat airway diseases. This delivery method ensures high concentrations of the medication in the targeted tissues, the airways, with generally lower systemic absorption and systemic adverse effects. Aerosolized antibiotics have been tested as treatment for bacterial infections in patients with cystic fibrosis (CF), non-CF bronchiectasis (NCFB), and ventilator-associated pneumonia (VAP). The most successful application of this to date is treatment of infections in patients with CF. It has been hypothesized that similar success would be seen in NCFB and in difficult-to-treat hospital-acquired infections such as VAP. This review summarizes the available evidence supporting the use of aerosolized antibiotics and addresses the specific considerations that clinicians should recognize when prescribing an aerosolized antibiotic for patients with CF, NCFB, and VAP.

  2. Assimilation of lidar signals: application to aerosol forecasting in the Mediterranean Basin

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2014-05-01

    Full Text Available This paper presents a new application of assimilating lidar signals to aerosol forecasting. It aims at investigating the impact of a ground-based lidar network on analysis and short-term forecasts of aerosols through a case study in the Mediterranean. To do so, we employ a data assimilation (DA algorithm based on the optimal interpolation method developed in the chemistry transport model (CTM {Polair3D of the air quality modelling platform POLYPHEMUS. We assimilate hourly-averaged normalised range corrected lidar signals (PR2 retrieved from a 72 h period of intensive and continuous measurements performed in July 2012 by ground-based lidar systems of the European Aerosol Research Lidar Network (EARLINET integrated into the Aerosols, Clouds, and Trace gases Research InfraStructure Network (ACTRIS and an additional system in Corsica deployed in the framework of the pre-ChArMEx (Chemistry-Aerosol Mediterranean Experiment/TRAQA (TRAnsport à longue distance et Qualité de l'Air campaign. This lidar campaign was dedicated to demonstrating the potential operationality of a research network like EARLINET and the potential usefulness of assimilation of lidar signals to aerosol forecasts. Particles with an aerodynamic diameter lower than 2.5 μm (PM2.5 and those with an aerodynamic diameter higher than 2.5 μm but lower than 10 μm (PM2.5–10 are analysed separately using the lidar observations at each DA step. First, we study the spatial and temporal influences of the assimilation of lidar signals on aerosol forecasting. We conduct sensitivity studies on algorithmic parameters, e.g. the horizontal correlation length (Lh used in the background error covariance matrix (50 km, 100 km or 200 km, the altitudes at which DA is performed (0.75–3.5 km, 1.0–3.5 km or 1.5–3.5 km a.g.l. and the assimilation period length (12 h or 24 h. We find that DA with Lh = 100 km and assimilation from 1.0 to 3.5 km a.g.l. during a 12 h assimilation period length leads to

  3. Teresa Andrés y la organización Cultura Popular: una propuesta de coordinación bibliotecaria (1936-1938

    Directory of Open Access Journals (Sweden)

    Seguí i Francés, Romà

    2011-12-01

    Full Text Available Teresa Andrés Zamora es conocida por su actividad al frente de la Sección de Bibliotecas de Cultura Popular. Este trabajo describe las relaciones que se establecieron entre Teresa Andrés y Cultura Popular, tras hacerse cargo de las responsabilidades del Ministerio de Instrucción Pública.

  4. ¿Herederas de un Nuevo Olimpo? : política e imagen en el escenario de las cortes de María Teresa y Margarita Teresa de Austria

    OpenAIRE

    Martínez Albero, Miquel

    2015-01-01

    Trabajo de final de máster del Máster en EEAA en Historia del Arte Español, sobre la importancia de la moda y el espectáculo a la hora de crear una imagen con fines políticos. El trabajo se constituye como un torneo figurado entre la Reina de Francia, María Teresa de Austria, y su medio hermana, Margarita Teresa, Emperatriz del Sacro Imperio, por la herencia de la monarquía hispánica en caso de un repentino fallecimiento de Carlos II.

  5. Decay control of "Femminello Santa Teresa" lemon fruits by prestorage high temperature conditioning

    OpenAIRE

    D'Aquino, Salvatore; Piga, Antonio; Agabbio, Mario Carlo Salvatore; Molinu, Maria Giovanna

    1998-01-01

    Marketing quality and juice chemical parameters of late harvested "Femminello Santa Teresa" lemon fruits (Citrus limon Burm), wrapped with a 15 mm heat shrinkable film or left unwrapped, and then either conditioned at 36°C for 72 hours in a 85-90%, relative humidity (RH) atmosphere or not conditioned, were determined over 3 months storage at 6°C and 95% RH or after 1 week at 20°C and 75% RH following each month of storage. Conditioning significantly reduced the incidence of decay caused by...

  6. Country western singer Teresa entertains at the Apollo/Saturn V Center

    Science.gov (United States)

    1999-01-01

    At the Apollo/Saturn V Center, country music recording artist Teresa performs a song, 'Brave New Girls,' written for astronaut Catherine 'Cady' Coleman, mission specialist on STS-93. She entertains participants and attendees of a women's forum held in the center. The attendees are planning to view the launch of STS- 93 at the Banana Creek viewing sight. Much attention has been generated over the launch due to Commander Eileen M. Collins, the first woman to serve as commander of a Shuttle mission. Liftoff is scheduled for July 20 at 12:36 a.m. EDT.

  7. Development, Application, and Transition of Aerosol and Trace Gas Products Derived from Next-Generation Satellite Observations to Operations

    Science.gov (United States)

    Berndt, Emily; Naeger, Aaron; Zavodsky, Bradley; McGrath, Kevin; LaFontaine, Frank

    2016-01-01

    NASA Short-term Prediction Research and Transition (SPoRT) Center has a history of successfully transitioning unique observations and research capabilities to the operational weather community to improve short-term forecasts. SPoRTstrives to bridge the gap between research and operations by maintaining interactive partnerships with end users to develop products that match specific forecast challenges, provide training, and assess the products in the operational environment. This presentation focuses on recent product development, application, and transition of aerosol and trace gas products to operations for specific forecasting applications. Recent activities relating to the SPoRT ozone products, aerosol optical depth composite product, sulfur dioxide, and aerosol index products are discussed.

  8. Molecular Chemistry of Organic Aerosols Through the Application of High Resolution Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

    2011-01-05

    Understanding of molecular composition and fundamental chemical transformations of organic aerosols (OA) during their formation and aging is both a major challenge and the area of greatest uncertainty in atmospheric research. Particularly little is known about fundamental relationship between the chemical composition and physicochemical properties of OA, their atmospheric history, evolution, and impact on the environment. Ambient soft-ionization methods combined with high-resolution mass spectrometry (HR-MS) analysis provide detailed information on the molecular content of OA that is pivotal for improved understanding of their complex composition, multi-phase aging chemistry, direct (light absorption and scattering) and indirect (aerosol-cloud interactions) effects on atmospheric radiation and climate, and health effects. The HR-MS methods can detect thousands of individual OA constituents at once, provide their elemental formulae from accurate mass measurements, and provide structural information based on tandem mass spectrometry. Integration with additional analytical tools, such as chromatography and UV/Vis absorption spectroscopy, makes it possible to further separate OA compounds by their polarity and ability to absorb solar radiation. The goal of this perspective is to describe modern HR-MS methods, review recent applications to field and laboratory studies of OA, and explain how the information obtained from HR-MS methods can be translated into improved understanding of OA chemistry.

  9. Applicability of the effective-medium approximation to heterogeneous aerosol particles

    Science.gov (United States)

    Mishchenko, Michael I.; Dlugach, Janna M.; Liu, Li

    2016-07-01

    The effective-medium approximation (EMA) is based on the assumption that a heterogeneous particle can have a homogeneous counterpart possessing similar scattering and absorption properties. We analyze the numerical accuracy of the EMA by comparing superposition T-matrix computations for spherical aerosol particles filled with numerous randomly distributed small inclusions and Lorenz-Mie computations based on the Maxwell-Garnett mixing rule. We verify numerically that the EMA can indeed be realized for inclusion size parameters smaller than a threshold value. The threshold size parameter depends on the refractive-index contrast between the host and inclusion materials and quite often does not exceed several tenths, especially in calculations of the scattering matrix and the absorption cross section. As the inclusion size parameter approaches the threshold value, the scattering-matrix errors of the EMA start to grow with increasing the host size parameter and/or the number of inclusions. We confirm, in particular, the existence of the effective-medium regime in the important case of dust aerosols with hematite or air-bubble inclusions, but then the large refractive-index contrast necessitates inclusion size parameters of the order of a few tenths. Irrespective of the highly restricted conditions of applicability of the EMA, our results provide further evidence that the effective-medium regime must be a direct corollary of the macroscopic Maxwell equations under specific assumptions.

  10. Espacio, afecto y subjetividad femenina en Arboleda de los enfermos de Teresa de Cartagena

    Directory of Open Access Journals (Sweden)

    Juan E. Villegas-Restrepo

    2015-12-01

    Full Text Available Este trabajo analiza el tratado de consuelo espiritual Arboleda de los enfermos de Teresa de Cartagena (c. 1415-1420a partir del desglose dialéctico entre las dinámicas espaciales (textuales, públicas, privadas, simbólicas que figuran en el texto y las cogniciones afectivas que dichas dinámicas propician. De manera más específica, el trabajo muestra cómo esta cognición afectiva, aunada a una serie de estrategias lingüísticas, le permiten a su autora ensamblar todo un espacio retórico femenino dentro del rígido andamiaje patriarcal de la época y, con ello, forjarse nuevas y más complejas maneras de pensarse a sí misma como sujeto femenino. This work analyzes Teresa de Cartagena’s treatise on spiritual counseling Arboleda de los enfermos based on a dialectical breakdown between the spatial dynamics (be them textual, public, private or symbolic that appear in the text and the affective cognitions that said dynamics elicit. More specifically, the work shows how this affective cognition, when coupled with a series of linguistic strategies, allow its author to assemble a female rhetorical space amidst the rigid patriarchal framework of the time and, with it, to forge new and more complex ways of imagining herself as a female subject.

  11. Ni ofelias ni amazonas, sino seres completos: aproximación a Teresa de Escoriaza

    Directory of Open Access Journals (Sweden)

    Palenque, Marta

    2006-06-01

    Full Text Available Teresa de Escoriaza is one of the first foreign correspondent in the spanish journalism history and was a reporter in the Melilla war in 1921. She was an active defending counsel of women rights too. Also as a professor of Spanish in EE.UU. she was a pioneer. She lived in New York during a lot of years and around it wrote some articles and a novel: El crisol de las razas (1929. This essay research about her life and work as writer and professor.Teresa de Escoriaza es una de las primeras corresponsales en el extranjero de la historia del periodismo español y ejerció como reportera en la Guerra de África, en 1921. También fue una activa defensora de los derechos de la mujer. Su labor como pionera se observa, además, en su trabajo como profesora de español en los EE.UU. Vivió muchos años en Nueva York, ciudad en torno a la que escribió varias crónicas y una novela: El crisol de las razas (1929. Este ensayo investiga acerca de su biografía y su labor como escritora y docente.

  12. La restauración del convento de Santa Teresa en Avila, España

    Directory of Open Access Journals (Sweden)

    de la Quintana Gordon, José Luis

    1989-10-01

    Full Text Available The Convent of Santa Teresa, Avila's third National Monument, has been in restoration since 1982. Its previous state was not good due to the unfavourable physical conditions of the site, to some un fortunate interventions suffered by its structure and to prolonged lack of use of many of its rooms. This paper describes the works of restoration of the building, which have been made applying contemporary intervention concepts but bearing in mind the modesty and firmness of style of Barefoot Carmelitans construction

    A partir de 1982, se desarrolló la restauración del Convento de Santa Teresa, tercer Monumento Nacional de la ciudad de Avila, en muy mal estado de conservación a causa de las desfavorables condiciones físicas de su emplazamiento, de algunas obras desafortunadas sufridas por sus estructuras y a la prolongada falta de uso de muchas de sus dependencias. Las páginas siguientes repasan los recientes trabajos de rehabilitación del edificio, en los cuales se aceptó el reto de aplicar criterios contemporáneos de intervención, sin alejarse del espíritu severo, sencillo y sólido propios de los edificios de la Regla Reformada

  13. Smartphone Air Quality and Atmospheric Aerosol Characterization for Public Health Applications

    Science.gov (United States)

    Strong, S. B.; Brown, D. M.; Brown, A.

    2014-12-01

    Air quality is a major global concern. Tracking and monitoring air quality provides individuals with the knowledge to make personal decisions about their health and investigate the environment in which they live. Satellite remote sensing and ground-based observations (e.g. Environmental Protection Agency, NASA Aerosol Robotic Network) of air quality is spatially and temporarlly limited and often neglects to provide individuals with the freedom to understand their own personal environment using their personal observations. Given the ubiquitous nature of smartphones, individuals have access to powerful processing and sensing capabilities. When coupled with the appropriate sensor parameters, filters, and algorithms, smartphones can be used both for 'citizen science' air quality applications and 'professional' scientific atmospheric investigations, alike, simplifying data analysis, processing, and improving deployment efficiency. We evaluate the validity of smartphone technology for air quality investigations using standard Cimel CE 318 sun photometry and Fourier Transform Infrared Spectroradiometer (FTIR) observations at specific locations.

  14. Efficacy of aerosol applications of methoprene and synergized pyrethrin against Tribolium castaneum adults and eggs.

    Science.gov (United States)

    Tucker, Angela M; Campbell, James F; Arthur, Frank H; Zhu, Kun Yan

    2014-06-01

    Experiments were performed to determine the efficacy of a single aerosol application of the insecticides methoprene and piperonyl butoxide-synergized pyrethrin, alone or in combination, and the insecticide carrier, Isopar M, against Tribolium castaneum (Herbst), the red flour beetle. The initial test exposed adults to insecticide treatments and placed male/female pairs in flour. All adults exposed to synergized pyrethrin were knocked down for at least 24 h after exposure but they recovered. High adult survival and similar average numbers of living F1 progeny were produced regardless of treatment exposure. In a separate test, insecticide treatments were directly applied to newly laid eggs, which resulted in the suppression of egg hatch. Synergized pyrethrin was the most effective insecticide (P castaneum egg hatch and development to the adult stage.

  15. The role of aerosols in cloud drop parameterizations and its applications in global climate models

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, C.C.; Penner, J.E. [Lawrence Livermore National Lab., CA (United States)

    1996-04-01

    The characteristics of the cloud drop size distribution near cloud base are initially determined by aerosols that serve as cloud condensation nuclei and the updraft velocity. We have developed parameterizations relating cloud drop number concentration to aerosol number and sulfate mass concentrations and used them in a coupled global aerosol/general circulation model (GCM) to estimate the indirect aerosol forcing. The global aerosol model made use of our detailed emissions inventories for the amount of particulate matter from biomass burning sources and from fossil fuel sources as well as emissions inventories of the gas-phase anthropogenic SO{sub 2}. This work is aimed at validating the coupled model with the Atmospheric Radiation Measurement (ARM) Program measurements and assessing the possible magnitude of the aerosol-induced cloud effects on climate.

  16. Application of the VH-TDMA technique to coastal ambient aerosols

    Science.gov (United States)

    Johnson, G.; Ristovski, Z.; Morawska, L.

    2004-08-01

    A newly developed VH-TDMA has been used for the first time to measure the volatile fractions and post volatilization hygroscopic growth factors of ambient aerosols in the coastal marine and urban environments. The results are compared with comparable data for laboratory generated aerosols of known composition. Measurements conducted on coastal Aitken mode particles showed volatilization behavior similar to laboratory generated aerosols composed of methane sulfonic acid and ammonium sulfate. Measurements conducted on 60 nm particles during nucleation events contained a greater fraction of material with similar volatility to ammonium sulfate than was found at other times. These particles were hygroscopic but less so than pure ammonium sulfate. Measurements conducted in the Brisbane central business district during sea breeze conditions show similar behavior to the coastal aerosol, but with additional low volatility species. This aerosol may originate from urban sources or from marine particles acquiring additional secondary aerosol species during transport.

  17. Trigger Analysis and Modelling of Very Large Debris Flows in Santa Teresa, Cusco, Southern Peru

    Science.gov (United States)

    Buis, Daniel; Huggel, Christian; Frey, Holger; Giráldez, Claudia; Rohrer, Mario; Christen, Marc; Portocarrero, César

    2014-05-01

    The Peruvian Andes have repeatedly been affected by large mass movements such as landslides, avalanches and debris flows. In 1998, two very large debris flows in the region of Machu Picchu (Sacsara and Ahobamba), southern Peru, destroyed the town of Santa Teresa, an important hydropower scheme and further infrastructure. The debris flows on the order of 5 to 25 million m3 volume rank among the largest recently observed events of this type worldwide. Despite their extreme dimensions, these events have not been studied in detail. An important limitation for more insight studies is the remote location of the mass flows and the very sparse information and data available for the study region. Neither triggering processes nor mass flow process characteristics have been understood to date. This study tries to fill some of these gaps in understanding that are critical to improved assessment of hazards and eventual risk reduction measures. For the trigger analysis we used data and information from field work, a limited number of ground based meteorological data, and complementary satellite derived data. Results indicate that in the case of the Sacsara event, heavy rainfall likely was a main trigger. For Ahobamba, antecedent rainfall as well as snow and ice melt leading to saturation of glacial sediments must have played an important role. Simulations with a dynamic debris flow model (RAMMS) allowed us to constrain a number of flow parameters such as flow height and velocity, runout distance and flow and deposition volumes. Strong surging flow behavior was detected, resulting in very large runout distance (exceeding 20 km); which rather depends on the largest single surge volume, not the total event volume. Based on the identification of potential mass flow sources we modeled a number of scenarios. The assessment of related hazards, including a preliminary hazard map, showed that several communities in catchments draining towards Santa Teresa are endangered by mass movements

  18. 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

  19. A Forgotten Short Story by Maria Teresa León

    Directory of Open Access Journals (Sweden)

    Ángeles Ezama Gil

    2012-05-01

    Full Text Available A short story titled “En los tentáculos de los siglos” and signed by Isabel Inghirami, pseudonym with which Maria Teresa Leon published his first writings, it appeared in the pages of the Revista de la Raza, in February and March of 1925. This story is similar to these included in La bella del mar amor. Cuentos castellanos (1930, that depends on the literary and the artistic tradition, specially on the last. In this forgotten story, is evident the influence of the images provided by the painting and the photography in the decades of 1910’s and 1920’s, and the influence of the Exhibition of regional customes celebrated in April of 1925, too.

  20. Teresa Wright, Accepting Authoritarianism. State-society relations in China’s reform era

    OpenAIRE

    Friedman, Edward

    2012-01-01

    Teresa Wright soutient que toutes les classes socioéconomiques chinoises, aussi variées soient-elles, dépendent de l’État pour accomplir leurs objectifs et qu’elles ne sont, par conséquent, pas prêtes à s’opposer au régime actuel. Pour l’auteur, l’industrialisation tardive, le développement dirigé par l’État et l’héritage socialiste sont autant de facteurs qui contribuent à influencer l’opinion publique. Aussi la population « accepte »-t-elle le Parti communiste chinois. La perspective défend...

  1. Quantitative ED-EPMA of Individual Particles and its Application for Characterization of Atmospheric Aerosol Particles

    Science.gov (United States)

    Ro, C.

    2008-12-01

    An electron probe X-ray microanalysis (EPMA) technique using an energy-dispersive X-ray detector with an ultra-thin window, named low-Z particle EPMA, has been developed. The low-Z particle EPMA allows the quantitative determination of concentrations of low-Z elements such as C, N, and O, as well as higher-Z elements that can be analyzed by conventional energy-dispersive EPMA (ED-EPMA). The quantitative determination of low-Z elements (using full Monte Carlo simulations, from the electron impact to the X-ray detection) in individual environmental particles has improved the applicability of single-particle analysis, especially in atmospheric environmental aerosol research; many environmentally important atmospheric particles, e.g. sulfates, nitrates, ammonium, and carbonaceous particles, contain low-Z elements. In addition, an expert system that can perform chemical speciation from the elemental composition data obtained by the low-Z particle EPMA has been developed. The low-Z particle EPMA was applied to characterize K-feldspar particle samples of which the chemical compositions are well defined by the use of various bulk analytical methods. Chemical compositions of the K-feldspar samples obtained from the low-Z particle EPMA turn out to be very close to those from bulk analyses. The low-Z particle EPMA technique has been applied for the characterization of atmospheric aerosol particle samples, including Asian dust, urban, and indoor particulate samples: (1) The extent of chemical modification of Asian dust particles sampled in Chuncheon and Incheon, Korea, during several Asian dust storm events occurred in 2002-2006 was investigated. Mixing of Asian dust with air pollutants and sea-salts strongly depends on the characteristics of Asian dust storm events such as air-mass backward trajectories. For instance, no significant chemical modification of mineral dust corresponded to fast moving air-masses at high altitudes. Inversely, extensive chemical modification was

  2. Santa Teresa en los conventos de monjas de Nueva España

    Directory of Open Access Journals (Sweden)

    Lavrin, Asuncion

    2015-12-01

    Full Text Available The transfer of the spiritual message of Saint Teresa to the viceregal court of New Spain tested the ability of Teresa’s teachings to adapt to new societies within the Spanish empire. Although the Carmelites founded only seven convents in Mexico, the Order succeeded in following the key precepts of the Teresian charisma, although nuanced by a baroque style of observance that insisted on spiritual and corporal mortification, complete humility and obedience, visionary experiences, and the imitation of Christ to achieve God’s love. Despite their small numbers, Carmelite nuns earned the respect of colonial society for their dedication to an ascetic way of life, personal poverty and the centrality of prayer.El trasplante de la espiritualidad teresiana a Nueva España fue una experiencia que puso a prueba la capacidad de adaptar su mensaje reformista a las circunstancias de nuevas sociedades en formación en el imperio español. Con sólo siete conventos femeninos en el nuevo virreinato, la Orden logró seguir los preceptos esenciales de Santa Teresa aunque matizados por una religiosidad barroca que insistía en mortificaciones espirituales y corporales, completa humildad y obediencia, experiencias visionarias, e imitatio Christi para acceder al amor de Dios. A pesar de su corto número las Carmelitas ganaron el respeto de la sociedad colonial por su dedicación a la vida ascética, la pobreza personal y la centralidad de la práctica de la oración.

  3. Bioaerosol detection by aerosol TOF-mass spectrometry: Application of matrix assisted laser desorption/ionisation

    NARCIS (Netherlands)

    Wuijckhuijse, A.L. van; Stowers, M.A.; Kientz, Ch.E.; Marijnissen, J.C.M.; Scarlett, B.

    2000-01-01

    In previous publications the use of an aerosol time of flight mass spectrometer was reported for the on-line measurements of aerosols (Weiss 1997, Kievit 1995). The apparatus is capable of measuring the size as well as the chemical composition, by the use of Laser Desorption/Ionisation (LDI), of an

  4. Bartolomé de las Casas en el siglo XIX: Fray Servando Teresa de Mier y Simón Bolívar

    OpenAIRE

    Barrera López, Trinidad

    2007-01-01

    El presente trabajo analiza el impacto de las ideas lascasianas en Fray Servando Teresa de Mier y su concepto de la independencia americana así como el eco bolivariano de la fama del sevillano. This article analyses the impact of La Casa’s ideas on Fray Servando Teresa de Mier and his concept of South American independence, along with the Bolivarian echo of the fame of the man from Seville.

  5. Microphysical properties of transported biomass burning aerosols in coastal regions, and application to improving retrievals of aerosol optical depth from SeaWiFS data

    Science.gov (United States)

    Sayer, A. M.; Hsu, N. C.; Bettenhausen, C.

    2013-05-01

    Due to the limited measurement capabilities of heritage and current spaceborne passive imaging radiometers, algorithms for the retrieval of aerosol optical depth (AOD) and related quantities must make assumptions relating to aerosol microphysical properties and surface reflectance. Over the ocean, surface reflectance can be relatively well-modelled, but knowledge of aerosol properties can remain elusive. Several field campaigns and many studies have examined the microphysical properties of biomass burning (smoke) aerosol. However, these largely focus on properties over land and near to the source regions. In coastal and open-ocean regions the properties of transported smoke may differ, due to factors such as aerosol aging, wet/dry deposition, and mixture with other aerosol sources (e.g. influence of maritime, pollution, or mineral dust aerosols). Hence, models based on near-source aerosol observations may be less representative of such transported smoke aerosols, introducing additional uncertainty into satellite retrievals of aerosol properties. This study examines case studies of transported smoke from select globally-distributed coastal and island Aerosol Robotic Network (AERONET) sites. These are used to inform improved models for over-ocean transported smoke aerosol for AOD retrievals from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS). These models are used in an updated version of the SeaWiFS Ocean Aerosol Retrieval (SOAR) algorithm, which has been combined with the Deep Blue algorithm over land to create a 13-year (1997-2010) high-quality record of AOD over land and ocean. Applying these algorithms to other sensors will enable the creation of a long-term global climate data record of spectral AOD.

  6. Evaluation of applicability of high-resolution multiangle imaging photo-polarimetric observations for aerosol atmospheric correction

    Science.gov (United States)

    Kalashnikova, Olga; Garay, Michael; Xu, Feng; Diner, David; Seidel, Felix

    2016-07-01

    tested prototype retrievals by comparing the retrieved aerosol concentration, size distribution, water-leaving radiance, and chlorophyll concentrations from Airborne Multiangle SpectroPolarimetric Imager-1 (AirMSPI-1) observations to values reported by the USC SeaPRISM AERONET-OC site off the coast of California. The retrieval was then applied to a variety of costal regions in California to evaluate variability in the water-leaving radiance under different atmospheric conditions. We will present results, and will discuss algorithm sensitivity and potential applications for future space-borne coastal monitoring.

  7. "Poner riquezas en mi entendimiento" sor Juana Inés de la Cruz y sor Teresa de Cartagena

    Directory of Open Access Journals (Sweden)

    Mª del Mar Cortés Timoner

    2004-01-01

    Full Text Available This article aims to show the resemblances that we can find between Admiraçión operum Dey written by Teresa de Cartagena in the mid-XVth century and Respuesta de sor Filotea de la Cruz written by sor Juana Inés de la Cruz two hundred years later. Both works are two epistles where the female´s intellectual capacity to know and to write is defended by a nun who was received critized for a former work. The religious Teresa de Cartagena –converse bishop Pablo Cartagena's granddaughter– wrote a moral essay that surprised male readers who considered that the text was a plagiarism. On the other hand, the hieronymite sister sor Juana Inés was reproached by a clergyman for having written the polemic treatise on theology Carta Atenagórica.

  8. 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

  9. The characterization of atmospheric aerosols: Application to heterogeneous gas-particle reactions

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, J.M.; Henson, B.F.; Wilson, K.R. [Los Alamos National Lab., NM (United States); Prather, K.A.; Noble, C.A. [Univ. of California, Riverside, CA (United States)

    1998-12-31

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project of the Los Alamos National Laboratory (LANL). The objective of this collaborative research project is the measurement and modeling of atmospheric aerosols and heterogeneous (gas/aerosol) chemical reactions. The two major accomplishments are single particle characterization of tropospheric particles and experimental investigation of simulated stratospheric particles and reactions thereon. Using aerosol time-of-flight mass spectrometry, real-time and composition measurements of single particles are performed on ambient aerosol samples. This technique allows particle size distributions for chemically distinct particle types to be described. The thermodynamics and chemical reactivity of polar stratospheric clouds are examined using vapor deposited thin ice films. Employing nonlinear optical methods, as well as other techniques, phase transitions on both water and acid ices are monitored as a function of temperature or the addition of gases.

  10. 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

  11. A new aerosol collector for quasi on-line analysis of particulate organic matter: the Aerosol Collection Module (ACM) and first applications with a GC/MS-FID

    Science.gov (United States)

    Hohaus, T.; Trimborn, D.; Kiendler-Scharr, A.; Gensch, I.; Laumer, W.; Kammer, B.; Andres, S.; Boudries, H.; Smith, K. A.; Worsnop, D. R.; Jayne, J. T.

    2010-10-01

    In many environments organic matter significantly contributes to the composition of atmospheric aerosol particles influencing its properties. Detailed chemical characterization of ambient aerosols is critical in order to understand the formation process, composition, and properties of aerosols and facilitates source identification and relative contributions from different types of sources to ambient aerosols in the atmosphere. However, current analytical methods are far from full speciation of organic aerosols and often require sampling times of up to one week. Offline methods are also subjected to artifacts during aerosol collection and storage. In the present work a new technique for quasi on-line compound specific measurements of organic aerosol particles was developed. The Aerosol Collection Module (ACM) focuses particles into a beam which is directed to a cooled sampling surface. The sampling takes place in a high vacuum environment where the gas phase from the sample volume is removed. After collection is completed volatile and semi-volatile compounds are evaporated from the collection surface through heating and transferred to a detector. For laboratory characterization the ACM was interfaced with a Gas Chromatograph Mass Spectrometer, Flame Ionization Detector system (GC/MS-FID), abbreviated as ACM GC-MS. The particle collection efficiency, gas phase transfer efficiency, and linearity of the ACM GC-MS were determined using laboratory generated octadecane aerosols. The ACM GC-MS is linear over the investigated mass range of 10 to 100 ng and a recovery rate of 100% was found for octadecane particles. The ACM GC-MS was applied to investigate secondary organic aerosol (SOA) formed from β-pinene oxidation. Nopinone, myrtanal, myrtenol, 1-hydroxynopinone, 3-oxonopinone, 3,7-dihydroxynopinone, and bicyclo[3,1,1]hept-3-ene-2-one were found as products in the SOA. The ACM GC-MS results are compared to quartz filter samples taken in parallel to the ACM GC

  12. Teresa Urrea: ¿Una Prechicana? Retos de memoria social,historia, nacionalismo de los chicanos de los Estados Unidos

    Directory of Open Access Journals (Sweden)

    Gillian Newell

    2002-01-01

    Full Text Available Las comunidades usan su pasado para construir su presente y futuro. Al mismo tiempo, el presente y el futuro de la gente constituyen su pasado. Esta investigación examina qué papel simbólico jugó la curandera y santa popular mexicana de finales del siglo XIX, Teresa Urrea, en el movimiento chicano de los años sesenta y setenta. Mediante un análisis de la política de formación de la identidad colectiva se comprende la construcción de una memoria social determinada y el uso del pasado en el presente. Examinando la historia del movimiento chicano y los trabajos relacionados, he investigado las maneras en las que se ha representado a Teresa, qué símbolos ha atribuido el chicanismo a su persona y el papel que ella jugó y continúa representando en la memoria social. Descubrí que la memoria de Teresa es de origen académico y que los chicanos intelectuales nunca lograron vincular esta construcción con la memoria popular.

  13. Critical Reflectance Derived from MODIS: Application for the Retrieval of Aerosol Absorption over Desert Regions

    Science.gov (United States)

    Wells, Kelley C.; Martins, J. Vanderlei; Remer, Lorraine A.; Kreidenweis, Sonia M.; Stephens, Graeme L.

    2012-01-01

    Aerosols are tiny suspended particles in the atmosphere that scatter and absorb sunlight. Smoke particles are aerosols, as are sea salt, particulate pollution and airborne dust. When you look down at the earth from space sometimes you can see vast palls of whitish smoke or brownish dust being transported by winds. The reason that you can see these aerosols is because they are reflecting incoming sunlight back to the view in space. The reason for the difference in color between the different types of aerosol is that the particles arc also absorbing sunlight at different wavelengths. Dust appears brownish or reddish because it absorbs light in the blue wavelengths and scatters more reddish light to space, Knowing how much light is scattered versus how much is absorbed, and knowin that as a function of wavelength is essential to being able to quantify the role aerosols play in the energy balance of the earth and in climate change. It is not easy measuring the absorption properties of aerosols when they are suspended in the atmosphere. People have been doing this one substance at a time in the laboratory, but substances mix when they are in the atmosphere and the net absorption effect of all the particles in a column of air is a goal of remote sensing that has not yet been completely successful. In this paper we use a technique based on observing the point at which aerosols change from brightening the surface beneath to darkening it. If aerosols brighten a surface. they must scatter more light to space. If they darken the surface. they must be absorbing more. That cross over point is called the critical reflectance and in this paper we show that critical reflectance is a monotonic function of the intrinsic absorption properties of the particles. This parameter we call the single scattering albedo. We apply the technique to MODIS imagery over the Sahara and Sahel regions to retrieve the single scattering albedo in seven wavelengths, compare these retrievals to ground

  14. Application of Positron Emission Tomography to Aerosol Transport Research in a Model of Human Lungs

    Directory of Open Access Journals (Sweden)

    Jicha M.

    2013-04-01

    Full Text Available Positron Emission Tomography (PET is a convenient method for measurement of aerosol deposition in complex models of lungs. It allows not only the evaluation of regional deposition characteristics but also precisely detects deposition hot spots. The method is based on a detection of a pair of annihilation photons moving in opposite directions as a result of positron – electron interaction after the positron emission decay of a suitable radioisotope. Liquid di(2-ethylhexyl sebacate (DEHS particles tagged with fluorine-18 as a radioactive tracer were generated by condensation monodisperse aerosol generator. Aerosol deposition was measured for three different inhalation flowrates and for two sizes of particles. Combination of PET with Computed Tomography (CT in one device allowed precise localisation of particular segments of the model. The results proved correlation of deposition efficiency with Stokes number, which means that the main deposition mechanism is inertial impaction. As a next task the methodology for tagging the solid aerosol particles with radioactive tracer will be developed and deposition of porous and fiber aerosols will be measured.

  15. Scattering Properties of Atmospheric Aerosols over Lanzhou City and Applications Using an Integrating Nephelometer

    Institute of Scientific and Technical Information of China (English)

    张武; 胡波; 陈长和; 杜萍; 张镭; 冯广泓

    2004-01-01

    The data, measured by a three-wavelength Integrating Nephelometer over Lanzhou City during the winters of 2001/2002 and 2002/2003 respectively, have been analyzed for investigating the scattering properties of atmospheric aerosols and exploring their relationship and the status of air pollution. The aerosol particle volume distribution is inverted with the measured spectral scattering coefficients. The results show that the daily variation of the aerosol scattering coefficients is in a tri-peak shape. The average ratio of backscattering coefficient to total scattering coefficient at 550 nm is 0.158; there exists an excellent correlation between the scattering coefficients and the concentration of PM10. The average ratio of the concentration of PM10 to the scattering coefficients is 0.37 g m-2, which is contingent on the optical parameters of aerosol particles such as the size distribution, etc.; an algorithm is developed for inverting the volume distribution of aerosol particles by using the histogram and Monte-Carlo techniques, and the test results show that the inversion is reasonable.

  16. The application of thermal methods for determining chemical composition of carbonaceous aerosols: a review.

    Science.gov (United States)

    Chow, Judith C; Yu, Jian Zhen; Watson, John G; Ho, Steven Sai Hang; Bohannan, Theresa L; Hays, Michael D; Fung, Kochy K

    2007-09-01

    Thermal methods of various forms have been used to quantify carbonaceous materials. Thermal/optical carbon analysis provides measurements of organic and elemental carbon concentrations as well as fractions evolving at specific temperatures in ambient and source aerosols. Detection of thermally desorbed organic compounds with thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) identifies and quantifies over 100 individual organic compounds in particulate matter (PM) samples. The resulting mass spectra contain information that is consistent among, but different between, source emissions even in the absence of association with specific organic compounds. TD-GC/MS is a demonstrated alternative to solvent extraction for many organic compounds and can be applied to samples from existing networks. It is amenable to field-deployable instruments capable of measuring organic aerosol composition in near real-time. In this review, thermal stability of organic compounds is related to chemical structures, providing a basis for understanding thermochemical properties of carbonaceous aerosols. Recent advances in thermal methods applied to determine aerosol chemical compositions are summarized and their potential for uncovering aerosol chemistry are evaluated. Current limitations and future research needs of the thermal methods are included.

  17. Evaluation of Air Pollution Applications of AERONET and MODIS Aerosol Column Optical Depth by Comparison with In Situ Measurements of Aerosol Light Scattering and Absorption for Reno, NV, USA

    Science.gov (United States)

    Loria Salazar, S.; Arnott, W. P.; Moosmuller, H.; Colucci, D.

    2012-12-01

    Reno, Nevada, USA is subject to typical urban aerosol, wind-blown dust, and occasional biomass burning smoke from anthropogenic and natural fires. Reno has complex air flow at levels relevant for aerosol transport. At times recirculating mountain and urban flow arrives from the Sierra Nevada, San Francisco, CA and Sacramento, CA. The urban plumes are further modified by biogenic forest emissions and secondary aerosol formation during transport over the Sierra Nevada Mountains to Reno. This complicates the use of MODIS aerosol optical depth (AOD) for air quality measurements in Reno. Our laboratory at the University of Nevada Reno has collocated multispectral photoacoustic instruments and reciprocal nephelometers to measure light absorption and light scattering coefficients as well as an AERONET operated CIMEL CE-318 ground-based sunphotometer. Preliminary measurements from August 2011 indicate substantially larger Cimel AOD than could be accounted for by use of the in situ aerosol extinction measurements combined with mixing height estimate. This poster presents new results comparing AERONET AOD and single scattering albedo and MODIS AOD with in situ measurements for summer and fall 2012, along with extensive back trajectory analysis, to evaluate conditions when satellite measurement may be useful for air pollution applications in Reno.

  18. Modelos para una santa. El necesario icono en la vida de Teresa de Ávila

    Directory of Open Access Journals (Sweden)

    Cea Gutiérrez, Antonio

    2006-06-01

    Full Text Available From the binomial consisting of cult images and devotional world, the author analyzes post-Tridentine personal spirituality in women’s convents of the 16th century. By looking into St. Theresa’s ascetico-mystical texts and extensive epistolary correspondence from an ethnoliterary perspective, the analyst can unveil the inside of this extraordinary woman and her social context. In her struggle for spiritual ascension, the Saint oscillated between austerity and hedonism, between privation and pleasure-seeking, between good and evil, holding Jesus Himself, Mary and the saints of her devotion as materialized target in the images of her.

    Desde el binomio imagen de culto y mundo devocional, se analiza el fenómeno de la espiritualidad personal, ya tridentino, en el espacio conventual femenino del siglo XVI. Bajo una perspectiva etnoliteraria y a través de los textos ascético-místicos de Teresa de Jesús y de su copiosa correspondencia epistolar, descubrimos el interior de esta extraordinaria mujer y su entorno social. En su lucha ascensional se debate la Santa entre la austeridad y el hedonismo, entre la privación y lo que le causa placer, entre el bien y el mal, teniendo al propio Cristo, a la Virgen y a los santos de su devoción como diana materializada en sus imágenes.

  19. Aerosol dry deposition on vegetative canopies. Part II: A new modelling approach and applications

    Science.gov (United States)

    Petroff, Alexandre; Mailliat, Alain; Amielh, Muriel; Anselmet, Fabien

    2008-05-01

    This paper presents a new approach for the modelling of aerosol dry deposition on vegetation. It follows a companion article, in which a review of the current knowledge highlights the need for a better description of the aerosol behaviour within the canopy [Petroff, A., Mailliat, A., Amielh, M., Anselmet, F., 2008. Aerosol dry deposition on vegetative canopies. Part I: Review of present knowledge. Atmospheric Environment, in press, doi:10.1016/j.atmosenv.2007.09.043]. Concepts from multi-phase flow studies are used for describing the canopy medium and deriving a time and space-averaged aerosol balance equation and the associated deposition terms. The closure of the deposition terms follows an up-scaling procedure based on the statistical distribution of the collecting elements. This aerosol transport model is then applied in a stationary and mono-dimensional configuration and takes into account the properties of the vegetation, the aerosol and the turbulent flow. Deposition mechanisms are Brownian diffusion, interception, inertial and turbulent impactions, and gravitational settling. For each of them, a parameterisation of the particle collection is derived and the quality of their predictions is assessed by comparison with wind-tunnel deposition measurements on coniferous twigs [Belot, Y., Gauthier, D., 1975. Transport of micronic particles from atmosphere to foliar surfaces. In: De Vries, D.A., Afgan, N.H. (Eds.), Heat and Mass Transfer in the Biosphere. Scripta Book, Washington, DC, pp. 583-591; Belot, Y., 1977. Etude de la captation des polluants atmosphériques par les végétaux. CEA, R-4786, Fontenay-aux-Roses; Belot, Y., Camus, H., Gauthier, D., Caput, C., 1994. Uptake of small particles by canopies. The Science of the Total Environment 157, 1-6]. Under a real canopy configuration, the predictions of the aerosol transport model compare reasonably well with detailed on-site deposition measurements of Aitken mode particles [Buzorius, G., Rannik, Ü., M

  20. Nanostructured Thin Film Synthesis by Aerosol Chemical Vapor Deposition for Energy Storage Applications

    Science.gov (United States)

    Chadha, Tandeep S.

    Renewable energy sources offer a viable solution to the growing energy demand while mitigating concerns for greenhouse gas emissions and climate change. This has led to a tremendous momentum towards solar and wind-based energy harvesting technologies driving efficiencies higher and costs lower. However, the intermittent nature of these energy sources necessitates energy storage technologies, which remain the Achilles heel in meeting the renewable energy goals. This dissertation focusses on two approaches for addressing the needs of energy storage: first, targeting direct solar to fuel conversion via photoelectrochemical water-splitting and second, improving the performance of current rechargeable batteries by developing new electrode architectures and synthesis processes. The aerosol chemical vapor deposition (ACVD) process has emerged as a promising single-step approach for nanostructured thin film synthesis directly on substrates. The relationship between the morphology and the operating parameters in the process is complex. In this work, a simulation based approach has been developed to understand the relationship and acquire the ability of predicting the morphology. These controlled nanostructured morphologies of TiO2 , compounded with gold nanoparticles of various shapes, are used for solar water-splitting applications. Tuning of light absorption in the visible-light range along with reduced electron-hole recombination in the composite structures has been demonstrated. The ACVD process is further extended to a novel single-step synthesis of nanostructured TiO2 electrodes directly on the current collector for applications as anodes in lithium-ion batteries, mainly for electric vehicles and hybrid electric vehicles. The effect of morphology of the nanostructures has been investigated via experimental studies and electrochemical transport modelling. Results demonstrate the exceptional performance of the single crystal one-dimensional nanostructures over granular

  1. A new aerosol collector for quasi on-line analysis of particulate organic matter: the Aerosol Collection Module (ACM and first applications with a GC/MS-FID

    Directory of Open Access Journals (Sweden)

    T. Hohaus

    2010-10-01

    Full Text Available In many environments organic matter significantly contributes to the composition of atmospheric aerosol particles influencing its properties. Detailed chemical characterization of ambient aerosols is critical in order to understand the formation process, composition, and properties of aerosols and facilitates source identification and relative contributions from different types of sources to ambient aerosols in the atmosphere. However, current analytical methods are far from full speciation of organic aerosols and often require sampling times of up to one week. Offline methods are also subjected to artifacts during aerosol collection and storage.

    In the present work a new technique for quasi on-line compound specific measurements of organic aerosol particles was developed. The Aerosol Collection Module (ACM focuses particles into a beam which is directed to a cooled sampling surface. The sampling takes place in a high vacuum environment where the gas phase from the sample volume is removed. After collection is completed volatile and semi-volatile compounds are evaporated from the collection surface through heating and transferred to a detector.

    For laboratory characterization the ACM was interfaced with a Gas Chromatograph Mass Spectrometer, Flame Ionization Detector system (GC/MS-FID, abbreviated as ACM GC-MS. The particle collection efficiency, gas phase transfer efficiency, and linearity of the ACM GC-MS were determined using laboratory generated octadecane aerosols. The ACM GC-MS is linear over the investigated mass range of 10 to 100 ng and a recovery rate of 100% was found for octadecane particles.

    The ACM GC-MS was applied to investigate secondary organic aerosol (SOA formed from β-pinene oxidation. Nopinone, myrtanal, myrtenol, 1-hydroxynopinone, 3-oxonopinone, 3,7-dihydroxynopinone, and bicyclo[3,1,1]hept-3-ene-2-one were found as products in the SOA. The ACM GC-MS results are compared to quartz filter

  2. Application of the characteristics-based sectional method to spatially varying aerosol formation and transport

    NARCIS (Netherlands)

    Frederix, E.M.A.; Kuczaj, A.K.; Nordlund, M.; Veldman, A.E.P.; Geurts, B.J.

    2017-01-01

    The characteristics-based ssolution. It is easy to verify thatectional method (CBSM) offers an Eulerian description of an internally mixed aerosol. It was shown to be robust and capable of exact preservation of lower order moments, allowing for highly skewed sectional droplet size distributions. In

  3. Retrieval of aerosol optical properties from OMI radiances using a multiwavelength algorithm : Application to Western Europe

    NARCIS (Netherlands)

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

    2008-01-01

    The Ozone Monitoring Instrument (OMI) multiwavelength algorithm has been developed to retrieve aerosol optical depth using OMI-measured reflectance at the top of the atmosphere. This algorithm was further developed by using surface reflectance data from a field campaign in Cabauw (The Netherlands),

  4. Application of computer-aided multi-scale modelling framework - Aerosol case study

    DEFF Research Database (Denmark)

    Heitzig, Martina; Gregson, Christopher; Sin, Gürkan;

    2011-01-01

    A computer-aided modelling tool for efficient multi-scale modelling has been developed and is applied to solve a multi-scale modelling problem related to design and evaluation of fragrance aerosol products. The developed modelling scenario spans three length scales and describes how droplets...

  5. Multifunction lidar system and its application for detecting aerosol and wind in boundary layer

    Science.gov (United States)

    Yang, Liquan; Qiu, Jinhuan; Zheng, Siping; Huang, Qirong

    1998-08-01

    A backscatter Nd-YAG lidar system has been constructed in our institute, which was designed to measure and image the four- dimensional structure the aerosol and to detect wind in lower atmosphere. It contains a Nd-YAG laser with maximum repetition rate of 15 pulses per second and a 20-cm telescope with maximum field of view of 3 mrad. A fast computer controlled angular scanning system provides can make the lidar to fire at the set position and time. Data logging system provides a logarithmic amplifier of 80 dB, 8 bit A/D conversion with range resolution of 7.5 m and high pixel resolution lidar images in a graphics computer. The system allows observations of inhomogeneities in natural aerosol in boundary layer showing the spatial distribution of aerosol scattering. A model to use triple angle azimuth scan method for measuring wind velocity is developed, which agrees well with the supposed wind in numerical experiment. The lidar system is been used in observations of aerosol and wind in boundary layer during February to July of 1998 and some results are presented.

  6. Applications of broadband cavity enhanced spectroscopy for measurements of trace gases and aerosols

    Science.gov (United States)

    Washenfelder, R. A.; Attwood, A. R.; Brock, C. A.; Brown, S. S.; Dube, W. P.; Flores, J. M.; Langford, A. O.; Min, K. E.; Rudich, Y.; Stutz, J.; Wagner, N.; Young, C.; Zarzana, K. J.

    2015-12-01

    Broadband cavity enhanced spectroscopy (BBCES) uses a broadband light source, optical cavity, and multichannel detector to measure light extinction with high sensitivity. This method differs from cavity ringdown spectroscopy, because it uses an inexpensive, incoherent light source and allows optical extinction to be determined simultaneously across a broad wavelength region.Spectral fitting methods can be used to retrieve multiple absorbers across the observed wavelength region. We have successfully used this method to measure glyoxal (CHOCHO), nitrous acid (HONO), and nitrogen dioxide (NO2) from ground-based and aircraft-based sampling platforms. The detection limit (2-sigma) in 5 s for retrievals of CHOCHO, HONO and NO2 is 32, 250 and 80 parts per trillion (pptv).Alternatively, gas-phase absorbers can be chemically removed to allow the accurate determination of aerosol extinction. In the laboratory, we have used the aerosol extinction measurements to determine scattering and absorption as a function of wavelength. We have deployed a ground-based field instrument to measure aerosol extinction, with a detection limit of approximately 0.2 Mm-1 in 1 min.BBCES methods are most widely used in the near-ultraviolet and visible spectral region. Recently, we have demonstrated measurements at 315-350 nm for formaldehyde (CH2O) and NO2. Extending the technique further into the ultraviolet spectral region will allow important additional measurements of trace gas species and aerosol extinction.

  7. Modeling secondary organic aerosol in an urban area: application to Paris, France

    Directory of Open Access Journals (Sweden)

    F. Couvidat

    2013-01-01

    Full Text Available A secondary organic aerosol (SOA model, H2O (Hydrophilic/Hydrophobic Organic, is evaluated over the Paris area. This model treats the formation of SOA with two kinds of surrogate species: hydrophilic species (which condense preferentially on an aqueous phase and hydrophobic species (which condense only on an organic phase. These surrogates species are formed from the oxidation in the atmosphere of volatile organic compounds (VOC by radicals (HO and NO3 and ozone. These VOC are either biogenic (isoprene, monoterpenes and sesquiterpenes or anthropogenic (mainly aromatic compounds. This model includes the formation of aerosols from different precursors (biogenic precursors, aromatics, and semi-volatile organic compounds (SVOC from traffic. The H2O aerosol model was incorporated into the Polyphemus air quality modeling platform and applied to the Paris area and evaluated by comparison to measurements performed during the Megapoli campaign in July 2009.

    The comparison to measurements in the suburbs and in the city center of Paris shows that the model gives satisfactory results for both elemental carbon (EC and organic carbon (OC. However, the model gives a peak of OC concentrations in the morning due to high emissions from traffic, which does not appear in measurements. Uncertainties in the modeled temperature, which can affect the gas-particle partitioning, in the partitioning of primary SVOC or underestimation of primary organic aerosol (POA evaporation by the model could explain the differences between model and measurements. Moreover, using a theoretical mechanism for the oxidation of primary SVOC and intermediate volatility organic compounds (IVOC, POA concentrations were found to be likely overestimated by models due to the use of simple partitioning constants (which do not take into account the affinity of a compound with the liquid aerosol solution or due to the assumption that the organic aerosol

  8. Modeling secondary organic aerosol in an urban area: application to Paris, France

    Directory of Open Access Journals (Sweden)

    F. Couvidat

    2012-09-01

    Full Text Available A secondary organic aerosol (SOA model, H2O (Hydrophilic/Hydrophobic Organic, is evaluated over the Paris area. This model treats the formation of SOA with two kinds of surrogate species: hydrophilic species (which condense preferentially on an aqueous phase and hydrophobic species (which condense only on an organic phase. These surrogates species are formed from the oxidation in the atmosphere of volatile organic compounds (VOC by radicals (HO and NO3 and ozone. These VOC are either biogenic (isoprene, monoterpenes and sesquiterpenes or anthropogenic (mainly aromatic compounds. This model includes the formation of aerosols from different precursors (biogenic precursors, aromatics, and semi-volatile organic compounds (SVOC from traffic. The H2O aerosol model was incorporated into the Polyphemus air quality modeling platform and applied to the Paris area and evaluated by comparison to measurements performed during the Megapoli campaign in July 2009.

    The comparison to measurements in the suburbs and in the city center of Paris shows that the model gives satisfactory results for both elemental carbon (EC and organic carbon (OC. However, the model gives a peak of OC concentrations in the morning due to high emissions from traffic, which does not appear in measurements. Uncertainties in the modeled temperature, which can affect the gas-particle partitioning, in the partitioning of primary SVOC or underestimation of primary organic aerosol (POA evaporation by the model could explain the differences between model and measurements. Moreover, using a theoretical mechanism for the oxidation of primary SVOC and intermediate volatility organic compounds (IVOC, POA concentrations were found to be likely overestimated by models due to the use of simple partitioning constants (which do not take into account the affinity of a compound with the liquid aerosol solution or due to the assumption that the organic aerosol

  9. Versos ao amado: mística e erotismo na poesia de Teresa D'ávila

    OpenAIRE

    Lima, Maria Graciele de

    2014-01-01

    Esta pesquisa está centrada na obra poética de Teresa d Ávila, escritora e poetisa espanhola que viveu no século XVI e se tornou conhecida por ser a fundadora da Ordem das Carmelitas Descalças. O corpus escolhido para análise é composto pelos poemas Mi Amado para mí, Traspasada e Buscate en mí, retirados da coletânea de poesia publicada em suas Obras Completas (1974) a fim de serem analisados à luz da Mística e do Erotismo, considerando também as marcas da autoria feminina presentes nos refer...

  10. [Guidelines for a prevalence survey of nosocomial infections in the University Hospital "Madre Teresa" in Tirana, Albania].

    Science.gov (United States)

    Sodano, L; Faria, S; Gjata, A; Kasneci, A; Byku, B; Schinaia, N

    2003-01-01

    The authors present guidelines for the first prevalence survey of nosocomial infections in the University Hospital "Madre Teresa" in Tirana (almost 1,600 beds), the only tertiary health-care centre in Albania. The survey is a joint project involving Italy and Albania, to be coordinated by the Italian National Health Institute. The paper describes goals, methodology and organization of the prevalence survey. The improvement of local expertise in epidemiology and microbiology is one of the most important goals. Therefore, Albanian personnel training and improvement of the infection microbiological diagnosis are fundamental aspects of the project.

  11. Modal aerosol dynamics modeling

    Energy Technology Data Exchange (ETDEWEB)

    Whitby, E.R.; McMurry, P.H.; Shankar, U.; Binkowski, F.S.

    1991-02-01

    The report presents the governing equations for representing aerosol dynamics, based on several different representations of the aerosol size distribution. Analytical and numerical solution techniques for these governing equations are also reviewed. Described in detail is a computationally efficient numerical technique for simulating aerosol behavior in systems undergoing simultaneous heat transfer, fluid flow, and mass transfer in and between the gas and condensed phases. The technique belongs to a general class of models known as modal aerosol dynamics (MAD) models. These models solve for the temporal and spatial evolution of the particle size distribution function. Computational efficiency is achieved by representing the complete aerosol population as a sum of additive overlapping populations (modes), and solving for the time rate of change of integral moments of each mode. Applications of MAD models for simulating aerosol dynamics in continuous stirred tank aerosol reactors and flow aerosol reactors are provided. For the application to flow aerosol reactors, the discussion is developed in terms of considerations for merging a MAD model with the SIMPLER routine described by Patankar (1980). Considerations for incorporating a MAD model into the U.S. Environmental Protection Agency's Regional Particulate Model are also described. Numerical and analytical techniques for evaluating the size-space integrals of the modal dynamics equations (MDEs) are described. For multimodal logonormal distributions, an analytical expression for the coagulation integrals of the MDEs, applicable for all size regimes, is derived, and is within 20% of accurate numerical evaluation of the same moment coagulation integrals. A computationally efficient integration technique, based on Gauss-Hermite numerical integration, is also derived.

  12. Die-Away Kinetics of Aerosolized Bacteria from Sprinkler Application of Wastewater

    OpenAIRE

    Teltsch, B; Shuval, H I; Tadmor, J

    1980-01-01

    A methodology for estimating, under field conditions, the microbial die-away constant (lambda) is presented. This constant may be used in predicting the aerosolized pathogenic microorganism concentrations downwind from a wastewater spray or aeration site by means of modified atmospheric diffusion equations. The mean lambda of Escherichia coli for very early morning runs was 8.8 X 10(-3)s-1, and that for afternoon runs was 6.6 X 10(-2)s-1.

  13. Large organic aerosols in a human exposure chamber : Applications in occupational dermatology and lung medicine

    OpenAIRE

    Lundgren, Lennart

    2006-01-01

    Exposure to large organic aerosol particles may cause respiratory and skin reactions. The use of human exposure chambers offers possibilities for experimental exposure challenges carried out with patients, in research and for investigations of the effects of exposure on the skin and in the respiratory tract. The present aim was to study the performance of modern human whole-body exposure chambers during generation of large organic particles, and to develop and test new me...

  14. Cuerpos místicos, almas ascéticas. Regulaciones del espíritu en la experiencia de Teresa de Ávila (1515-1582).

    OpenAIRE

    Mònica Balltondre

    2009-01-01

    En esta tesis se investiga la antropología que subyace a la espiritualidad mística femenina de mediados del siglo XVI castellano, de la mano de Teresa de Ávila, conocida como Teresa de Jesús. Ella construyó una forma espiritual de vivirse que le permitió encuadrar sus experiencias a partir de tradiciones teológicas, como la mística, y de otros saberes como la filosofía natural y la medicina de su tiempo. Se examinan para ver cómo conceptualizó sus relaciones sobrenaturales y qué le aportaron ...

  15. Santa Teresa of Jesus as Example for the Novo Hispanic Mystics. The Work of Alonso Ramos about Catarina de San Juan

    Directory of Open Access Journals (Sweden)

    Gisela von Wobeser

    2016-11-01

    Full Text Available The life and work of Santa Teresa of Jesus had a great influence on the New Spain spiritual atmosphere by enabling a more intimate and direct relationship of women with God and contribute to the proliferation of nuns and beatified. In the Wonders of the Omnipotence and Miracles of the Grace in the life of the Venerable Servant of God Catharina of San Joan, Alonso Ramos writes the biography of Catarina of San Juan, a free slave considered saint, to whom in many passages compares with Santa Teresa. The purpose of Ramos was to create a female life model based on Teresian spirituality and values.

  16. Palmitic Acid on Salt Subphases and in Mixed Monolayers of Cerebrosides: Application to Atmospheric Aerosol Chemistry

    Directory of Open Access Journals (Sweden)

    Ellen M. Adams

    2013-10-01

    Full Text Available Palmitic acid (PA has been found to be a major constituent in marine aerosols, and is commonly used to investigate organic containing atmospheric aerosols, and is therefore used here as a proxy system. Surface pressure-area isotherms (π-A, Brewster angle microscopy (BAM, and vibrational sum frequency generation (VSFG were used to observe a PA monolayer during film compression on subphases of ultrapure water, CaCl2 and MgCl2 aqueous solutions, and artificial seawater (ASW. π-A isotherms indicate that salt subphases alter the phase behavior of PA, and BAM further reveals that a condensation of the monolayer occurs when compared to pure water. VSFG spectra and BAM images show that Mg2+ and Ca2+ induce ordering of the PA acyl chains, and it was determined that the interaction of Mg2+ with the monolayer is weaker than Ca2+. π-A isotherms and BAM were also used to monitor mixed monolayers of PA and cerebroside, a simple glycolipid. Results reveal that PA also has a condensing effect on the cerebroside monolayer. Thermodynamic analysis indicates that attractive interactions between the two components exist; this may be due to hydrogen bonding of the galactose and carbonyl headgroups. BAM images of the collapse structures show that mixed monolayers of PA and cerebroside are miscible at all surface pressures. These results suggest that the surface morphology of organic-coated aerosols is influenced by the chemical composition of the aqueous core and the organic film itself.

  17. Temperature of cutaneous and subcutaneous tissue during the application of aerosols in rats

    Directory of Open Access Journals (Sweden)

    Andre de Oliveira Teixeira

    2014-10-01

    Full Text Available This study compared the thermal changes of cutaneous and subcutaneous tissues exposed to different aerosols. Thirty-six adults Wistar rats were arranged in two treatment groups, one exposed to methyl salicylate (GSM; n = 9 skin and n = 9 subcutaneous and the other exposed to diclofenac diethylammonium (GDD; n = 9 skin and n = 9 subcutaneous aerosols. Five jets were applied for one-second through an apparatus to reduce spray dispersion (3 cmdiameter in the lateral left thigh of the animals. Temperatures were measured every minute (min. during 30 min., with a digital thermometer. In the skin tissue the sensor was positioned manually, in the subcutaneous tissue it was surgically inserted through the rear face and positioned in the lateral thigh. The skin temperature has homogeneously reduced in both groups. In the subcutaneous tissue the GDD has induced hypothermia from the 2nd to 20th min., the lowest temperature was recorded on the 7th min. (-3.6 ± 0.2ºC in relation to basal. Lowering the temperature by GSM took place from the 1st to 21st min, and the lowest temperature occurred on the 1st min (-9.7 ± 0.5ºC in relation to basal. In the three initial minutes the GSM had temperatures 25, 10 and 5% lower than the GDD. Aerosols have induced hypothermia in the tissues, while the GSM has decreased faster and reached lower values of temperature shown in the subcutaneous tissue.

  18. Synthesis of Poly(N-isopropylacrylamide) Microcapsules for Drug Delivery Applications via UV Aerosol Photopolymerization

    Science.gov (United States)

    Roberson, Nicole; Denmark, Daniel; Witanachchi, Sarath

    Hybrid drug delivery systems composed of thermoresponsive polymers and magnetic nanoparticles have been developed using chemical methods to deliver controlled amounts of a biotherapeutic to target tissue. These methods can be expensive, time intensive, and produce impure composites due to the use of surfactants during polymer synthesis. In this study, UV aerosol photopolymerization is used to synthesize N-isoplopylacrylamide (NIPAM) monomers, N,N-methylenebisacrylamide (MBA) crosslinker, and irgacure 2959 photoinitiator into the transporting microcapsule for drug delivery. The method of UV aerosol photopolymerization allows for the continuous, cost effective, and time efficient synthesis of a high concentration of pure polymers in a short amount of time; toxic surfactants are not necessary. Optimal NIPAM monomer, MBA crosslinker, and irgacure 2959 photoinitiator concentrations were tested and analyzed to synthesize a microcapsule with optimal conditions for controlled drug delivery. Scanning Electron Microscope (SEM) imaging reveals that synthesis of polymer microcapsules of about 30 micrometers in size is effective through UV aerosol photopolymerization. Findings will contribute greatly to the field of emergency medicine. This work was supported by the United States Army (Grant No. W81XWH1020101/3349).

  19. Effect of illumination intensity and light application time on secondary organic aerosol formation from the photooxidation of α-pinene

    Institute of Scientific and Technical Information of China (English)

    LIU Xianyun; ZHANG Weijun; HUANG Mingqiang; WANG Zhenya; HAO Liqing; ZHAO Wenwu

    2009-01-01

    Secondary organic aerosol (SOA) formation from hydroxyl radical (OH·) initiated photooxidation of α-pinene was investigated in a home-made smog chamber. The size distribution of SOA particles was measured using aerodynamic particle sizer spectrometer. The effect of illumination intensity and light application time on SOA formation for α-pinene was evaluated. Experimental results show that the concentration of SOA particles increased significantly with the increasing of illumination intensity, and the light application time, the concentration, and the size of SOA particals were also increased. The factors influencing the formation of SOA were also discussed. This atricle compared the effect of α-pinene with that of toluene, and discussed the contribution of α-pinene to SOA formation.

  20. Sor Teresa Juliana de Santo Domingo, «Chicaba», or Writing on the Other’s Skin Sor Teresa Juliana de Santo Domingo, «Chicaba» o escribir en la piel del otro

    Directory of Open Access Journals (Sweden)

    Beatriz FERRÚS ANTÓN

    2010-06-01

    Full Text Available Sor Teresa Juliana de Santo Domingo, Chicaba was the first Black writer in Spanish. She was a nun in Salamanca during the 18th Century who wrote about her religious life. Her text was used by Juan Carlos Paniagua to write a hagiography. The aim of this articvle is to comment on Paniagua’s text in relation to the religious tradition of the time, especially of women. The relationship between women-writing-skin is decisive.Sor Teresa Juliana de Santo Domingo, Chicaba, es la primera escritora negra conocida en español. Monja en Salamanca durante el siglo XVIII , escribió una vida religiosa a partir de la cual Juan Carlos Paniagua redactaría una hagiografía. El objetivo de este artículo es analizar el texto de Paniagua dentro de la tradición de escritura religiosa de este tiempo, en especial femenina, prestando especial atención a la asociación que entre mujer-escritura-color de la piel se construye en el mismo.

  1. Clara Schumann, Teresa Carreño, Rosita Renard: la condición de mujer en sus carreras musicales Clara Schumann, Teresa Carreño, Rosita Renard: Their Female Condition in their Musical Careers

    Directory of Open Access Journals (Sweden)

    Miguel Castillo Didier

    2010-06-01

    Full Text Available Clara Wieck, después Schumann, alemana, Teresa Carreño, venezolana, Rosita Renard, chilena, se distinguen como algunas de las más destacadas pianistas a lo largo de un poco más de una centuria, desde algo antes de mediados del siglo XIX a la mitad del XX. Hay paralelismos y también contrastes en sus vidas y sus carreras. Pero tanto el transcurrir de sus existencias como el del quehacer musical al que se dedicaron están marcados por hechos ligados a su condición de mujeres. Tratamos de hacer un paralelo entre sus vidas y entre el desarrollo de sus carreras destacando las particularidades y dificultades que en ambos planos les impuso la condición de mujeres.Clara Wieck, later Schumann, Germán, Teresa Carreño, Venezuelan, Rosita Renard, Chilean, have all of them distinguished as some ofthe most outstandingpianists along a little more than a century, from befare the mid 19th century fo the mid 20th. There are parallelisms and contrasts in their Uves and careers. Rut their Uves as well as their musical development were strongly affected by facts linked to their condition as women. We have tried to establish these parálisis, higlighting particularities and difficulties arisingfrom their condition of women.

  2. Application of matrix-assisted laser desorption/ionization to on-line aerosol time-of-flight mass spectrometry

    NARCIS (Netherlands)

    Stowers, M.A.; Wuijckhuijse, A.L. van; Marijnissen, J.C.M.; Scarlett, B.; Baar, B.L.M. van; Kientz, Ch.E.

    2000-01-01

    Matrix-assisted laser desorption/ionization (MALDI) mass spectra were obtained from single biological aerosol particles using an aerosol time-of- flight mass spectrometer (ATOFMS). The inlet to the ATOFMS was coupled with an evaporation/condensation flow cell that allowed the aerosol to be coated wi

  3. High temporal resolution estimates of columnar aerosol microphysical parameters from spectrum of aerosol optical depth by linear estimation: application to long-term AERONET and star-photometry measurements

    Science.gov (United States)

    Perez-Ramirez, D.; Veselovskii, I.; Whiteman, D. N.; Suvorina, A.; Korenskiy, M.; Kolgotin, A.; Holben, B.; Dubovik, O.; Siniuk, A.; Alados-Arboledas, L.

    2015-08-01

    This work deals with the applicability of the linear estimation technique (LE) to invert spectral measurements of aerosol optical depth (AOD) provided by AERONET CIMEL sun photometers. The inversion of particle properties using only direct-sun AODs allows the evaluation of parameters such as effective radius (reff) and columnar volume aerosol content (V) with significantly better temporal resolution than the operational AERONET algorithm which requires both direct sun and sky radiance measurements. Sensitivity studies performed demonstrate that the constraints on the range of the inversion are very important to minimize the uncertainties, and therefore estimates of reff can be obtained with uncertainties less than 30 % and of V with uncertainties below 40 %. The LE technique is applied to data acquired at five AERONET sites influenced by different aerosol types and the retrievals are compared with the results of the operational AERONET code. Good agreement between the two techniques is obtained when the fine mode predominates, while for coarse mode cases the LE results systematically underestimate both reff and V. The highest differences are found for cases where no mode predominates. To minimize these biases, correction functions are developed using the multi-year database of observations at selected sites, where the AERONET retrieval is used as the reference. The derived corrections are tested using data from 18 other AERONET stations offering a range of aerosol types. After correction, the LE retrievals provide better agreement with AERONET for all the sites considered. Finally, the LE approach developed here is applied to AERONET and star-photometry measurements in the city of Granada (Spain) to obtain day-to-night time evolution of columnar aerosol microphysical properties.

  4. Application of the Statistical Oxidation Model (SOM to Secondary Organic Aerosol formation from photooxidation of C12 alkanes

    Directory of Open Access Journals (Sweden)

    J. H. Seinfeld

    2013-02-01

    Full Text Available Laboratory chamber experiments are the main source of data on the mechanism of oxidation and the secondary organic aerosol (SOA forming potential of volatile organic compounds. Traditional methods of representing the SOA formation potential of an organic do not fully capture the dynamic, multi-generational nature of the SOA formation process. We apply the Statistical Oxidation Model (SOM of Cappa and Wilson (2012 to model the formation of SOA from the formation of the four C12 alkanes, dodecane, 2-methyl undecane, cyclododecane and hexylcyclohexane, under both high- and low-NOx conditions, based upon data from the Caltech chambers. In the SOM, the evolution of reaction products is defined by the number of carbon (NC and oxygen (NO atoms, and the model parameters are (1 the number of oxygen atoms added per reaction, (2 the decrease in volatility upon addition of an oxygen atom and (3 the probability that a given reaction leads to fragmentation of the molecules. Optimal fitting of the model to chamber data is carried out using the measured SOA mass concentration and the aerosol O:C atomic ratio. The use of the kinetic, multi-generational SOM is shown to provide insights into the SOA formation process and to offer promise for application to the extensive library of existing SOA chamber experiments that is available.

  5. Application of the Statistical Oxidation Model (SOM to secondary organic aerosol formation from photooxidation of C12 Alkanes

    Directory of Open Access Journals (Sweden)

    J. H. Seinfeld

    2012-10-01

    Full Text Available Laboratory chamber experiments are the main source of data on the mechanism of oxidation and the secondary organic aerosol (SOA forming potential of volatile organic compounds. Traditional methods of representing the SOA formation potential of an organic do not fully capture the dynamic, multi-generational nature of the SOA formation process. We apply the Statistical Oxidation Model (SOM of Cappa and Wilson (2012 to model the formation of SOA from the formation of the four C12 alkanes, dodecane, 2-methyl undecane, cyclododecane and hexylcyclohexane, under both high- and low-NOx conditions, based upon data from the Caltech chambers. In the SOM, the evolution of reaction products is defined by the number of carbon (NC and oxygen (NO atoms, and the model parameters are (1 the number of oxygen atoms added per reaction, (2 the decrease in volatility upon addition of an oxygen atom and (3 the probability that a given reaction leads to fragmentation of the molecules. Optimal fitting of the model to chamber data is carried out using the measured SOA mass concentration and the aerosol O : C atomic ratio. The use of the kinetic, multi-generational SOM is shown to provide insights into the SOA formation process and to offer promise for application to the extensive library of existing SOA chamber experiments that is available.

  6. Development of a new aerosol monitoring system and its application in Fukushima nuclear accident related aerosol radioactivity measurement at the CTBT radionuclide station in Sidney of Canada

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Weihua, E-mail: weihua.zhang@hc-sc.gc.ca [Radiation Protection Bureau, Health Canada, 775 Brookfield Road, Ottawa, Ontario, K1A 1C1 (Canada); Bean, Marc; Benotto, Mike; Cheung, Jeff; Ungar, Kurt; Ahier, Brian [Radiation Protection Bureau, Health Canada, 775 Brookfield Road, Ottawa, Ontario, K1A 1C1 (Canada)

    2011-12-15

    A high volume aerosol sampler ('Grey Owl') has been designed and developed at the Radiation Protection Bureau, Health Canada. Its design guidance is based on the need for a low operational cost and reliable sampler to provide daily aerosol monitoring samples that can be used as reference samples for radiological studies. It has been developed to provide a constant air flow rate at low pressure drops ({approx}3 kPa for a day sampling) with variations of less than {+-}1% of the full scale flow rate. Its energy consumption is only about 1.5 kW for a filter sampling over 22,000 standard cubic meter of air. It has been demonstrated in this Fukushima nuclear accident related aerosol radioactivity monitoring study at Sidney station, B.C. that the sampler is robust and reliable. The results provided by the new monitoring system have been used to support decision-making in Canada during an emergency response. - Highlights: > A new high volume aerosol sampler ('Grey Owl') has been developed in this study. > It operates at low pressure drops with low energy consumption. > The variation of air flow rate is less than {+-}1% of the full scale. > Fukushima accident nuclide monitoring at Sidney shows that it is robust and reliable.

  7. Lidar development with applications to the stratosphere- troposphere exchange and tropical aerosol detection

    Science.gov (United States)

    Castleberg, Paul Andrew

    1997-06-01

    Lidar remote sensing of the atmosphere is explored through the use and development of the Rayleigh and resonance lidar systems at the Arecibo Observatory (18.3oN, 66.8oW). Resonance lidar capabilities have been demonstrated at the Arecibo Observatory for both sodium and potassium. The initiation, development, and details of the lidar system, based on an alexandrite solid state ring laser, are discussed. We present initial resonance observations, as well as the exciting potential for dual- wavelength upper troposphere and lower stratosphere aerosol observations. The Arecibo five year Rayleigh lidar data base and latitudinal snap shot from the Space Shuttle LITE experiment are used to study the temporal and spatial distributions of volcanic aerosols entrained in the stratosphere. The results support recent global models which suggest an extra tropical suction pump is responsible for mass being up drawn across the tropical tropopause, moved poleward, then pushed downward in the extratropics (Holton et al., 1995). The aerosol scattering wavelength dependence is introduced through the Angstrom coefficient to estimate aerosol size distributions. The analysis is extended to upper tropospheric cirrus clouds. Initial observations of two types of cirrus are presented. We speculate that one type are the remnants of convective activity, while the second grow in the cold tropical tropopause. We present a single example of the wavelength dependence as an example of the utility of multi-wavelength lidar analysis. Local stratospheric/tropospheric exchanges are investigated through a detailed discussion of lidar, radar, and balloon observations of temperatures and wind field fluctuations. On a single remarkable night, September 14-15, 1994, we captured two unique examples of convective activity at the tropopause and in the lower stratosphere. The first is a large scale molecular density depletion (temperature enhancement) just below the tropopause, which we believe is the result of

  8. On-Line Characterization of Aerosols Formed in a Jet Flow Condenser for Analytical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Chr.; Mohr, M. [EMPA Duebendorf (Switzerland)

    2004-03-01

    With a jet flow condenser (JFC) aerosol particles can be generated from gases containing high boiling substances. This can be used for transferring these substances from the hot carrier gas into an analytical device. In this study we have investigated the particle number size distribution (NSD) produced in two JFCs with different geometry. Experiments were performed with elemental zinc as a model substance. Zinc has been volatilised in a tubular furnace and the particles generated in the JFC were characterized on-line by a Scanning Mobility Particle Sizer (SMPS). (author)

  9. O êxtase de Teresas: o sacro e o profano na Literatura e nas Artes (The ecstasy of Teresas: the sacred and the profane in the Literature and in the Arts - DOI: 10.5752/P.2175-5841.2013v11n31p843

    Directory of Open Access Journals (Sweden)

    Flávia Vieira da Silva do Amparo

    2013-09-01

    Full Text Available No altar da Igreja de Santa Maria della Vittoria (Roma, encontramos a bela escultura de Bernini, denominada “O êxtase de Santa Teresa”. Símbolo da entrega ao gozo espiritual, a escultura do artista italiano representa Santa Teresa de Ávila recebendo do anjo a seta do amor divino, reprodução perfeita do êxtase místico e religioso. Esse trabalho tem como objetivo analisar a ocorrência de Teresas na literatura brasileira, como heroínas divididas entre o sacro e o profano. Propomos o estudo do romance Tereza Batista: cansada de guerra, de Jorge Amado, a partir da intertextualidade com a tradição literária baiana, de Gregório de Matos e Castro Alves, e em contraponto ao pensamento religioso da obra lírica de Santa Teresa de Ávila, em diálogo com a escultura extática da santa, criada por Gian Lorenzo Bernini. Palavras-chaves: Santa Teresa de Ávila. Jorge Amado. Castro Alves. Gregório de Matos. Sagrado. Profano.   Abstract At the altar of the Church of Santa Maria della Vittoria (Rome, is located the Bernini’s sculpture, called "The Ecstasy of St. Teresa." Symbol of surrender to spiritual joy, the sculpture by the Italian artist represents St. Teresa of Avila affected by the arrow of the Angel, perfect reproduction of the religious and mystical ecstasy. This article aims to analyze the occurrence of Teresas in Brazilian literature, as heroines divided between the sacred and the profane. We propose to study of the novel Tereza Batista: cansada de guerra, by Jorge Amado, from the intertextuality with the literary tradition of Bahia, of Gregorio de Mattos and Castro Alves, and in opposition to the religious thought of the lyrical work of St. Teresa de Ávila, in dialogue with the ecstatic sculpture of St. Tereza, by Gian Lorenzo Bernini. Keywords: St. Teresa of Ávila. Jorge Amado. Castro Alves. Gregório de Mattos. Sacred. Profane. 

  10. Application of AERONET Single Scattering Albedo and Absorption Angstrom Exponent to Classify Dominant Aerosol Types during DRAGON Campaigns

    Science.gov (United States)

    Giles, D. M.; Holben, B. N.; Eck, T. F.; Schafer, J.; Crawford, J. H.; Kim, J.; Sano, I.; Liew, S.; Salinas Cortijo, S. V.; Chew, B. N.; Lim, H.; Smirnov, A.; Sorokin, M.; Kenny, P.; Slutsker, I.

    2013-12-01

    Aerosols can have major implications on human health by inducing respiratory diseases due to inhalation of fine particles from biomass burning smoke or industrial pollution and on radiative forcing whereby the presence of absorbing aerosol particles (e.g., black carbon) increases atmospheric heating. Aerosol classification techniques have utilized aerosol loading and aerosol properties derived from multi-spectral and multi-angle observations by ground-based (e.g., AERONET) and satellite instrumentation (e.g., MISR). Aerosol Robotic Network (AERONET) data have been utilized to determine aerosol types by implementing various combinations of measured aerosol optical depth or retrieved size and absorption aerosol properties (e.g., Gobbi et al., 2007; Russell et al., 2010). Giles et al. [2012] showed single scattering albedo (SSA) relationship with extinction Angstrom exponent (EAE) can provide an estimate of the general classification of dominant aerosol types (i.e., desert dust, urban/industrial pollution, biomass burning smoke, and mixtures) based on data from ~20 AERONET sites located in known aerosol source regions. In addition, the absorption Angstrom exponent relationship with EAE can provide an indication of the dominant absorbing aerosol type such as dust, black carbon, brown carbon, or mixtures of them. These classification techniques are applied to the AERONET Level 2.0 quality assured data sets collected during Distributed Regional Aerosol Gridded Observational Network (DRAGON) campaigns in Maryland (USA), Japan, South Korea, Singapore, Penang (Malaysia), and California (USA). An analysis of aerosol type classification for DRAGON sites is performed as well as an assessment of the spatial variability of the aerosol types for selected DRAGON campaigns. Giles, D. M., B. N. Holben, T. F. Eck, A. Sinyuk, A. Smirnov, I. Slutsker, R. R. Dickerson, A. M. Thompson, and J. S. Schafer (2012), An analysis of AERONET aerosol absorption properties and classifications

  11. Una mirada crítica sobre Lengua Madre Una conversación con María Teresa Andruetto (23 de diciembre de 2013

    Directory of Open Access Journals (Sweden)

    Costanza Borghi

    2014-06-01

    Full Text Available Una mirada crítica sobre Lengua MadreUna conversación con María Teresa Andruetto(23 de diciembre de 2013por Costanza Borghi, Serena Cappellini, Sara De Simone,Alma Martini, Valentina Paleari, Marco Pozzoni,Annamaria Rodio, Beatrice Tresoldi

  12. Birds of Santa Teresa, Espírito Santo, Brazil: do humans add or subtract species?

    Directory of Open Access Journals (Sweden)

    Edwin O. Willis

    2002-11-01

    Full Text Available In uplands and lowlands of Santa Teresa, central Espírito Santo State, Brazil, 405 bird species were confirmed by field, museum, and literature studies. Of these, 16 seem to have disappeared, while 67 other species seem to have been lost from the lowlands (where no large biological reserves exist. Due to a suggestion that human areas add species to beta-diversity, we verified that up to 79 species now present have perhaps "invaded" with human activity (and 10 others are likely to invade, a total similar to that for lost species. However, lost species are often rare and invading species often widespread, resulting in exchange of "Picassos for Coca-Cola bottles." Furthermore, gains exceed losses only when large biological reserves are present, as in the uplands (Nova Lombardia, Santa Lúcia Reserves, each with over 250 species. Small or irregular reserves usually lose well over half their species, and these are only partly replaced by the invaders, resulting in net losses of up to half the local avifaunas. If one lists only 31 probable invaders, rather than a possible 79, things are even worse; net losses occur even in the entire township and near reserves, reaching over 200 species around lowland private reserves. Future "productive" development of human areas can eliminate or maltreat many invading species, too. While approving taxes on improductive use of land, as it leaves other areas free, we suggest that many current local "uses," such as for coffee, are "luxury" production and could be taxed.Nas terras altas e baixas de Santa Teresa, região central do Estado de Espírito Santo, Brasil, 405 espécies de aves foram confirmadas por estudos de campo, museu e de literatura. Destas, 16 parecem ter desaparecido, enquanto outras 67 espécies parecem ter sido perdidas nas baixadas (onde não existem reservas biológicas de grande extensão. Baseado na sugestão de que as áreas humanas adicionam espécies à beta diversidade, nós verificamos que

  13. Uncertainty evaluation in correlated quantities: application to elemental analysis of atmospheric aerosols;Evaluacion de la incertidumbre en cantidades correlacionadas: aplicacion al analisis elemental de aerosoles atmosfericos

    Energy Technology Data Exchange (ETDEWEB)

    Espinosa, A.; Miranda, J.; Pineda, J. C., E-mail: miranda@fisica.unam.m [UNAM, Instituto de Fisica, Circuito de la Investigacion Cientifica s/n, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2010-07-01

    One of the aspects that are frequently overlooked in the evaluation of uncertainty in experimental data is the possibility that the involved quantities are correlated among them, due to different causes. An example in the elemental analysis of atmospheric aerosols using techniques like X-ray Fluorescence (X RF) or Particle Induced X-ray Emission (PIXE). In these cases, the measured elemental concentrations are highly correlated, and then are used to obtain information about other variables, such as the contribution from emitting sources related to soil, sulfate, non-soil potassium or organic matter. This work describes, as an example, the method required to evaluate the uncertainty in variables determined from correlated quantities from a set of atmospheric aerosol samples collected in the Metropolitan Area of the Mexico Valley and analyzed with PIXE. The work is based on the recommendations of the Guide for the Evaluation of Uncertainty published by the International Organization for Standardization. (Author)

  14. Development of a new aerosol monitoring system and its application in Fukushima nuclear accident related aerosol radioactivity measurement at the CTBT radionuclide station in Sidney of Canada.

    Science.gov (United States)

    Zhang, Weihua; Bean, Marc; Benotto, Mike; Cheung, Jeff; Ungar, Kurt; Ahier, Brian

    2011-12-01

    A high volume aerosol sampler ("Grey Owl") has been designed and developed at the Radiation Protection Bureau, Health Canada. Its design guidance is based on the need for a low operational cost and reliable sampler to provide daily aerosol monitoring samples that can be used as reference samples for radiological studies. It has been developed to provide a constant air flow rate at low pressure drops (∼3 kPa for a day sampling) with variations of less than ±1% of the full scale flow rate. Its energy consumption is only about 1.5 kW for a filter sampling over 22,000 standard cubic meter of air. It has been demonstrated in this Fukushima nuclear accident related aerosol radioactivity monitoring study at Sidney station, B.C. that the sampler is robust and reliable. The results provided by the new monitoring system have been used to support decision-making in Canada during an emergency response.

  15. Application of flow cytometry and cell sorting to the bacterial analysis of environmental aerosol samples.

    Science.gov (United States)

    Hernlem, Bradley J; Ravva, Subbarao V

    2007-12-01

    Flow cytometry (FCM) combined with viability staining is a useful tool in discerning viable bacteria in environmental samples where traditional culture methods may fail. Contamination of aerosol samples with dust and other non-biological particles can interfere with accurate sample analysis and therefore there is a desire to exclude those particles from analysis. Particles were sorted according to their light scattering properties, cultured and isolates obtained. Isolates were cultured in suspension and reanalyzed by flow cytometry. The isolates were also analyzed and identified by DNA sequence analysis. Isolates with statistically similar light scattering properties shared common sequence identification. Isolates exhibited distinct light scattering profiles that roughly correlated with their originating gate, but often the peak of the profile was outside that gate.

  16. Verification and application of the extended Spectral Deconvolution Algorithm (SDA+ methodology to estimate aerosol fine and coarse mode extinction coefficients in the marine boundary layer

    Directory of Open Access Journals (Sweden)

    K. C. Kaku

    2014-03-01

    Full Text Available The Spectral Deconvolution Algorithm (SDA and SDA+ (extended SDA methodologies can be employed to separate the fine and coarse mode extinction coefficients from measured total aerosol extinction coefficients, but their common use is currently limited to AERONET Aerosol Optical Depth (AOD. Here we provide the verification of the SDA+ methodology on a non-AERONET aerosol product, by applying it to fine and coarse mode nephelometer and Particle Soot Absorption Photometer (PSAP data sets collected in the marine boundary layer. Using datasets collected on research vessels by NOAA PMEL, we demonstrate that with accurate input, SDA+ is able to predict the fine and coarse mode scattering and extinction coefficient partition in global data sets representing a range of aerosol regimes. However, in low-extinction regimes commonly found in the clean marine boundary layer, SDA+ output accuracy is sensitive to instrumental calibration errors. This work was extended to the calculation of coarse and fine mode scattering coefficients with similar success. This effort not only verifies the application of the SDA+ method to in situ data, but by inference verifies the method as a whole for a host of applications, including AERONET. Study results open the door to much more extensive use of nephelometers and PSAPs, with the ability to calculate fine and coarse mode scattering and extinction coefficients in field campaigns that do not have the resources to explicitly measure these values.

  17. Recent Advances in the Development and Application of Power Plate Transducers in Dense Gas Extraction and Aerosol Agglomeration Processes

    Science.gov (United States)

    Riera, E.; Cardoni, A.; Gallego-Juárez, J. A.; Acosta, V. M.; Blanco, A.; Rodríguez, G.; Blasco, M.; Herranz, L. E.

    Power ultrasound (PU) is an emerging, innovative, energy saving and environmental friendly technology that is generating a great interest in sectors such as food and pharmaceutical industries, green chemistry, environmental pollution, and other processes, where sustainable and energy efficient methods are required to improve and/or produce specific effects. Two typical effects of PU are the enhancement of mass transfer in gases and liquids, and the induction of particle agglomeration in aerosols. These effects are activated by a variety of mechanisms associated to the nonlinear propagation of high amplitude ultrasonic waves such as diffusion, agitation, entrainment, turbulence, etc. During the last years a great effort has been jointly made by the Spanish National Research Council (CSIC) and the company Pusonics towards introducing novel processes into the market based on airborne ultrasonic plate transducers. This technology was specifically developed for the treatment of gas and multiphasic media characterized by low specific acoustic impedance and high acoustic absorption. Different strategies have been developed to mitigate the effects of the nonlinear dynamic behavior of such ultrasonic piezoelectric transducers in order to enhance and stabilize their response at operational power conditions. This work deals with the latter advances in the mitigation of nonlinear problems found in power transducers; besides it describes two applications assisted by ultrasound developed at semi-industrial and laboratory scales and consisting in extraction via dense gases and particle agglomeration. Dense Gas Extraction (DGE) assisted by PU is a new process with a potential to enhance the extraction kinetics with supercritical CO2. Acoustic agglomeration of fine aerosol particles has a great potential for the treatment of air pollution problems generated by particulate materials. Experimental and numerical results in both processes will be shown and discussed.

  18. Seasonal variability in aerosol optical and physical characteristics estimated using the application of the Ängström formula over Mohal in the northwestern Himalaya, India

    Indian Academy of Sciences (India)

    Raj Paul Guleria; Jagdish Chandra Kuniyal; Nand Lal Sharma; Pitamber Prasad Dhyani

    2012-06-01

    Investigations of aerosol optical and physical characteristics using the application of Ängström formula and second order polynomial fit were carried out from April 2006 to March 2009 at Mohal in the Kullu valley. The measurements of spectral aerosol optical depths (AODs) were conducted using multiwavelength radiometer (MWR). The AOD at 0.5 m wavelength on daily basis (mean ± standard deviation) for the entire three-year study period is obtained as 0.24 ± 0.08. Seasonal variations show the highest AOD at 0.5 m wavelength with ∼0.34 ± 0.08 during pre-monsoon (April–July), followed by ∼0.26 ± 0.08 during monsoon (August–September), ∼0.21 ± 0.05 during post-monsoon (October–November) and ∼0.20 ± 0.07 during winter (December–March). The seasonal values indicate that the AOD at 0.5 m wavelength is decreasing from pre-monsoon to winter with a notable reduction around 41%. The Ängström parameters using least square method is not found appropriate for size distribution particularly when coarse mode aerosols dominate. The coefficients of second order polynomial fit are more appropriate for the discrimination of aerosol size or irrespective to the dominance of either of the aerosols size. The difference in coefficient of polynomial fit is used to get confirmation on the dominant mode during different seasons. Study reveals that about 93%, 72% and 59% of AOD spectra are dominated by a wide range of fine mode fractions or mixture of modes during post-monsoon, winter and monsoon, respectively. On the other hand, during pre-monsoon, 72% of AOD spectra are found to be dominated by coarse mode aerosols.

  19. Os Filmes (Descritos de Ana Teresa Pereira: Nightmare, de Alfred Hitchcock, e The Double, de David Cronenberg

    Directory of Open Access Journals (Sweden)

    Amândio Pereira Reis

    2014-03-01

    Full Text Available Starting with a comparative reading of an ekphrastic text by Callistratus (3rd century AD and taking support from various studies on ekphrasis as a literary practice, from antiquity to present times until its acceptance as an intermedial literary genre, it is our goal to analyze two short stories by Ana Teresa Pereira which invent non-existent films by Hitchcock and Cronenberg. Therefore, we will have to confront a range of problems associated with ekphrastic description – the dialectic between reality and fiction; truth and falsity; imagination and reading – and with the (impossibilities of representation through image and/or words, including a set of questions posed by the specific transmedial relation that A. T. Pereira’s texts establish between Literature and Cinema. We will also take into account the concept of Pavle Levi’s “written film” as one possibility, among others, of genre identification for these narratives.

  20. En permanente construcción. La recreación de la figura de santa Teresa en las semblanzas biográficas de sus hijas

    Directory of Open Access Journals (Sweden)

    Atienza López, Ángela

    2015-12-01

    Full Text Available Beyond her biographical recreations, Teresa of Jesus personality was also represented in other textual scenes. Biographical sketches of discalced Carmelites included in the chronicles of the order will incorporate references to the founding mother, too. In our paper we analyse the ingredients of the teresian portrait that was reflected in these narrations, highlighting how, besides the miracles and Teresa’s supernatural side, these texts also strongly emphasized her human and earthly dimensions. The Teresa that stands out is a woman with authority, the founder and enterprising, the politician and organizer, the woman of action and ruler, one who had an attentive and watchful eye over all the matters that affected her convents and her reforming projects; the woman who had a close relationship with the social world, who dealt with ecclesiastical and lay powers… In summary, a Teresa far beyond the established conceptions about women at that time and the roles assigned to them also sneaks into the pages of the chroniclers; even when many scholars have ignored it over time, in benefit of an image of St Teresa closer to hagiography.La figura de Teresa de Jesús, además de en sus recreaciones biográficas, se presentó y representó también en otros escenarios textuales. Las semblanzas biográficas de las carmelitas descalzas que contenían las crónicas de la orden también incorporarán referencias a la madre fundadora. Estudiamos en nuestro trabajo cuáles fueron los ingredientes del retrato teresiano que se fueron reflejando en esas narraciones, poniendo de manifiesto cómo, al lado de la dimensión «milagrosa» y de la faceta sobrenatural de Teresa, estos textos enfatizan mucho la dimensión más humana y terrenal. La Teresa que sobresale es la mujer con autoridad, la fundadora y emprendedora, la política y la organizadora, la mujer de acción y de gobierno, la de mirada atenta y vigilante a todos los asuntos que pudieran afectar a sus

  1. Application of air ions for bacterial de-colonization in air filters contaminated by aerosolized bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yang Seon, E-mail: rup2r@yonsei.ac.kr [School of Mechanical Engineering, Yonsei University, 262 Seongsanno, Seodaemun-Gu, Seoul, 120-749 (Korea, Republic of); Yoon, Ki Young, E-mail: yky810921@yonsei.ac.kr [Exhaust Emission Engineering Team, Hyundai Motor Company, Hwaseong 445-706, Republic of Korea (Korea, Republic of); Park, Jae Hong, E-mail: cheap@yonsei.ac.kr [School of Mechanical Engineering, Yonsei University, 262 Seongsanno, Seodaemun-Gu, Seoul, 120-749 (Korea, Republic of); Hwang, Jungho, E-mail: hwangjh@yonsei.ac.kr [School of Mechanical Engineering, Yonsei University, 262 Seongsanno, Seodaemun-Gu, Seoul, 120-749 (Korea, Republic of)

    2011-01-15

    We aerosolized the Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epidermidis) bacteria and collected them on membrane filters. Then we generated air ions by applying a high voltage to a carbon fiber tip and applied them to the contaminated filters. The antibacterial efficiency was not significantly affected by the bacteria being Gram-positive or Gram-negative, however, negative ions showed a lower antibacterial efficiency than positive ions to both E. coli and S. epidermidis, even though the concentration of negative air ions was much higher than that of positive air ions. With a field emission scanning electron microscope (FE-SEM) images and fluorescence microscopy images using a LIVE/DEAD BacLight Bacterial Viability Kit, electrostatic disruption of the bacteria was found to be the dominant antibacterial effect. - Research Highlights: {yields}This study examined the effects of air ions generated by a carbon fiber ionizer on the inactivation of bioaerosols. {yields}When the ion exposure time and the ion generation concentration were increased, the antibacterial efficiency increased. {yields}The bioaerosols carried a significant number of negative electrical charges. {yields}Negative ions showed lower antibacterial efficiency than positive ions to both E. coli and S. epidermidis, even though the concentration of negative air ions was much higher than that of positive air ions.

  2. Assessment of dry and wet atmospheric deposits of radioactive aerosols: application to Fukushima radiocaesium fallout.

    Science.gov (United States)

    Gonze, Marc-André; Renaud, Philippe; Korsakissok, Irène; Kato, Hiroaki; Hinton, Thomas G; Mourlon, Christophe; Simon-Cornu, Marie

    2014-10-07

    The Fukushima Dai-ichi nuclear accident led to massive atmospheric deposition of radioactive substances onto the land surfaces. The spatial distribution of deposits has been estimated by Japanese authorities for gamma-emitting radionuclides through either airborne monitoring surveys (since April 2011) or in situ gamma-ray spectrometry of bare soil areas (since summer 2011). We demonstrate that significant differences exist between the two surveys for radiocaesium isotopes and that these differences can be related to dry deposits through the use of physically based relationships involving aerosol deposition velocities. The methodology, which has been applied to cesium-134 and cesium-137 deposits within 80-km of the nuclear site, provides reasonable spatial estimations of dry and wet deposits that are discussed and compared to atmospheric numerical simulations from the Japanese Atomic Energy Agency and the French Institute of Radioprotection and Nuclear Safety. As a complementary approach to numerical simulations, this field-based analysis has the possibility to contribute information that can be applied to the understanding and assessment of dose impacts to human populations and the environment around Fukushima.

  3. Application of the LSQR algorithm in non-parametric estimation of aerosol size distribution

    Science.gov (United States)

    He, Zhenzong; Qi, Hong; Lew, Zhongyuan; Ruan, Liming; Tan, Heping; Luo, Kun

    2016-05-01

    Based on the Least Squares QR decomposition (LSQR) algorithm, the aerosol size distribution (ASD) is retrieved in non-parametric approach. The direct problem is solved by the Anomalous Diffraction Approximation (ADA) and the Lambert-Beer Law. An optimal wavelength selection method is developed to improve the retrieval accuracy of the ASD. The proposed optimal wavelength set is selected by the method which can make the measurement signals sensitive to wavelength and decrease the degree of the ill-condition of coefficient matrix of linear systems effectively to enhance the anti-interference ability of retrieval results. Two common kinds of monomodal and bimodal ASDs, log-normal (L-N) and Gamma distributions, are estimated, respectively. Numerical tests show that the LSQR algorithm can be successfully applied to retrieve the ASD with high stability in the presence of random noise and low susceptibility to the shape of distributions. Finally, the experimental measurement ASD over Harbin in China is recovered reasonably. All the results confirm that the LSQR algorithm combined with the optimal wavelength selection method is an effective and reliable technique in non-parametric estimation of ASD.

  4. Application of HPLC-Charged Aerosol Detection%HPLC-电雾式检测器的应用

    Institute of Scientific and Technical Information of China (English)

    刘路; 高旋; 杨永健

    2012-01-01

    电雾式检测器(CAD)是一种新型通用型液相色谱检测器,具有较宽的动态监测范围、较高的灵敏度和重复性、不依赖于化学结构的信号响应一致性、应用广泛和操作简捷等优点,应用于中性、酸性、碱性及两性物质等,特别是无紫外吸收、非挥发性或半挥发性物质的检测.本文简要介绍了CAD检测器的工作原理及其应用.%Charged aerosol detection (CAD) is a novel generic HPLC detector. CAD system has some advantages such as broad dynamic response range, good precision and sensitivity, response independent of chemical properties, widespread application and simple and reliable operation. CAD has been applied for the analysis of neutral, acidic, basic and zwitterionic compounds without volatility and ultraviolet activity. This review introduces its operation principle and selected applications.

  5. Strategy to use the Terra Aerosol Information to Derive the Global Aerosol Radiative Forcing of Climate

    Science.gov (United States)

    Kaufman, Yoram J.; Tanre, Didier; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Terra will derive the aerosol optical thickness and properties. The aerosol properties can be used to distinguish between natural and human-made aerosol. In the polar orbit Terra will measure aerosol only once a day, around 10:30 am. How will we use this information to study the global radiative impacts of aerosol on climate? We shall present a strategy to address this problem. It includes the following steps: - From the Terra aerosol optical thickness and size distribution model we derive the effect of aerosol on reflection of solar radiation at the top of the atmosphere. In a sensitivity study we show that the effect of aerosol on solar fluxes can be derived 10 times more accurately from the MODIS data than derivation of the optical thickness itself. Applications to data over several regions will be given. - Using 1/2 million AERONET global data of aerosol spectral optical thickness we show that the aerosol optical thickness and properties during the Terra 10:30 pass are equivalent to the daily average. Due to the aerosol lifetime of several days measurements at this time of the day are enough to assess the daily impact of aerosol on radiation. - Aerosol impact on the top of the atmosphere is only part of the climate question. The INDOEX experiment showed that addressing the impact of aerosol on climate, requires also measurements of the aerosol forcing at the surface. This can be done by a combination of measurements of MODIS and AERONET data.

  6. Aerosol Jet Printing and Its Application in Organic Devices%气溶胶喷墨打印在有机器件制备中的应用

    Institute of Scientific and Technical Information of China (English)

    杨春和; 唐爱伟; 滕枫

    2012-01-01

    Aerosol jet printing is a new printing technique developed in recent years. Film forming on the substrate is achieved with the jet printing of the ink aerosol stream. This enables the aerosol jet printing to realize high-resolution printing with wide-range inks of different viscosity. The working mechanism, the application in the fabrication of organic devices, and the future of the aerosol jet printing are reviewed and envisioned.%气溶胶喷墨打印是近年来新出现的一种打印技术.通过将形成的墨水气溶胶喷射至基底表面而成膜,使得气溶胶喷墨打印对墨水的黏度要求低、打印分辨率好、适用墨水的范围广.文章对气溶胶喷墨打印技术的基本原理、在有机器件制备方面的应用以及将来的改进等方面进行了简介和评价.

  7. Quantitative energy-dispersive electron probe X-ray microanalysis for single-particle analysis and its application for characterizing atmospheric aerosol particles

    Indian Academy of Sciences (India)

    Shila Maskey; Chul-Un Ro

    2011-02-01

    An energy-dispersive electron probe X-ray microanalysis (ED-EPMA) technique using an energy-dispersive X-ray detector with an ultra-thin window, designated as low-Z particle EPMA, has been developed. The low-Z particle EPMA allows the quantitative determination of concentrations of low-Z elements such as C, N and O, as well as higher-Z elements that can be analysed by conventional ED-EPMA. The quantitative determination of low-Z elements (using full Monte Carlo simulations, from the electron impact to the X-ray detection) in individual particles has improved the applicability of single-particle analysis, especially in atmospheric environmental aerosol research; many environmentally important atmospheric particles, e.g. sulphates, nitrates, ammonium and carbonaceous particles, contain low-Z elements. To demonstrate its practical applicability, the application of the low-Z particle EPMA for the characterization of Asian Dust, urban and subway aerosol particles is shown herein. In addition, it is demonstrated that the Monte Carlo calculation can also be applied in a quantitative single-particle analysis using transmission electron microscopy (TEM) coupled with energy-dispersive X-ray spectrometry (EDX), showing that the technique is useful and reliable for the characterization of submicron aerosol particles

  8. Application of several activity coefficient models to water-organic-electrolyte aerosols of atmospheric interest

    Directory of Open Access Journals (Sweden)

    T. Raatikainen

    2005-01-01

    Full Text Available In this work, existing and modified activity coefficient models are examined in order to assess their capabilities to describe the properties of aqueous solution droplets relevant in the atmosphere. Five different water-organic-electrolyte activity coefficient models were first selected from the literature. Only one of these models included organics and electrolytes which are common in atmospheric aerosol particles. In the other models, organic species were solvents such as alcohols, and important atmospheric ions like NH4+ could be missing. The predictions of these models were compared to experimental activity and solubility data in aqueous single electrolyte solutions with 31 different electrolytes. Based on the deviations from experimental data and on the capabilities of the models, four predictive models were selected for fitting of new parameters for binary and ternary solutions of common atmospheric electrolytes and organics. New electrolytes (H+, NH4+, Na+, Cl-, NO3- and SO42- and organics (dicarboxylic and some hydroxy acids were added and some modifications were made to the models if it was found useful. All new and most of the existing parameters were fitted to experimental single electrolyte data as well as data for aqueous organics and aqueous organic-electrolyte solutions. Unfortunately, there are very few data available for organic activities in binary solutions and for organic and electrolyte activities in aqueous organic-electrolyte solutions. This reduces model capabilities in predicting solubilities. After the parameters were fitted, deviations from measurement data were calculated for all fitted models, and for different data types. These deviations and the calculated property values were compared with those from other non-electrolyte and organic-electrolyte models found in the literature. Finally, hygroscopic growth factors were calculated for four 100 nm organic-electrolyte particles and these predictions were compared to

  9. Smart Magnetically Responsive Hydrogel Nanoparticles Prepared by a Novel Aerosol-Assisted Method for Biomedical and Drug Delivery Applications

    Directory of Open Access Journals (Sweden)

    Ibrahim M. El-Sherbiny

    2011-01-01

    Full Text Available We have developed a novel spray gelation-based method to synthesize a new series of magnetically responsive hydrogel nanoparticles for biomedical and drug delivery applications. The method is based on the production of hydrogel nanoparticles from sprayed polymeric microdroplets obtained by an air-jet nebulization process that is immediately followed by gelation in a crosslinking fluid. Oligoguluronate (G-blocks was prepared through the partial acid hydrolysis of sodium alginate. PEG-grafted chitosan was also synthesized and characterized (FTIR, EA, and DSC. Then, magnetically responsive hydrogel nanoparticles based on alginate and alginate/G-blocks were synthesized via aerosolization followed by either ionotropic gelation or both ionotropic and polyelectrolyte complexation using CaCl2 or PEG-g-chitosan/CaCl2 as crosslinking agents, respectively. Particle size and dynamic swelling were determined using dynamic light scattering (DLS and microscopy. Surface morphology of the nanoparticles was examined using SEM. The distribution of magnetic cores within the hydrogels nanoparticles was also examined using TEM. In addition, the iron and calcium contents of the particles were estimated using EDS. Spherical magnetic hydrogel nanoparticles with average particle size of 811 ± 162 to 941 ± 2 nm were obtained. This study showed that the developed method is promising for the manufacture of hydrogel nanoparticles, and it represents a relatively simple and potential low-cost system.

  10. Application of computer-aided multi-scale modelling framework – Aerosol case study

    DEFF Research Database (Denmark)

    Heitzig, Martina; Sin, Gürkan; Glarborg, Peter

    -aided methods provide. The key prerequisite of computer-aided product-process engineering is however the availability of models of different types, forms and application modes. The development of the models required for the systems under investigation tends to be a challenging and time-consuming task involving...... numerous steps, expert skills and different modelling tools. This motivates the development of a computer-aided modelling framework that supports the user during model development, documentation, analysis, identification, application and re-use with the goal to increase the efficiency of the modelling...... generation, optimal equation ordering, eigenvalue analysis. Once the models have been constructed and analysed the modelling framework incorporates 3 application work-flows for: identification, simulation and design. For these application work-flows different solvers that can solve a large range of different...

  11. Antón Perulero: Un cuento inédito de María Teresa León

    Directory of Open Access Journals (Sweden)

    Marina Bedia, Marta

    2002-12-01

    Full Text Available This article offers a short story, apparently unpublished, by Maria Teresa León: «Antón Perulero», wich was not collected in any book of stories. Probably written in Argentina, at the beginning of the 40's, it has been found in a notebook of this authoress, wich is kept in the National Library (Madrid. The story is destined to a readership of children, and its characters (Maricastaña, Mátalas Callando, Antón Perulero himself are taken from the world of proverbs, set phrases and children's songs; the interest in children's literature and in folklore had been present in Maria Teresa Leon's writing from its beginning.Este artículo presenta un cuento, al parecer inédito, de María Teresa León: «Antón Perulero», no recogido en ninguna de sus colecciones de relatos. Escrito probablemente en Argentina, a principios de los años 40, ha sido encontrado en un cuaderno manuscrito de la autora, que se conserva en la Biblioteca Nacional de Madrid. El relato está destinado al público infantil, y sus personajes (Maricastaña, Mátalas Callando o el propio Antón Perulero están extraídos del mundo de los refranes, las frases hechas y las canciones para niños; el interés por la literatura infantil y por el folklore había estado presente en la escritura de María Teresa León desde sus inicios.

  12. Teresa Andrés Zamora (1907-1946: el compromiso social y político como arma de cultura

    Directory of Open Access Journals (Sweden)

    Seguí i Francés, Romà

    2010-12-01

    Full Text Available La biografía de Teresa Andrés Zamora (Villalba de los Alcores, 1907- París, 1946 es un claro ejemplo de cómo el compromiso de una mujer republicana a través de la cultura se transformó en beligerancia política. Este artículo quiere mostrar una imagen de Teresa Andrés más profunda que la de una bibliotecaria que militó en el PCE, pretendiendo reconstruir su recorrido vital tanto en la faceta académica como profesional y política, con el objetivo de presentar una evolución que va desde su paso por la Residencia de Señoritas hasta su prematura muerte en París. Teresa Andrés Zamora representa una generación de mujeres republicanas que fue leal a la II República, trabajando incansablemente durante la Guerra Civil, y que padeció el exilio en una Francia ocupada.

  13. Hybrid 95: Software for the design of hybrid systems, Potrerillo of Santa Teresa; Hybrid 95: Software de diseno de sistemas hibridos, Potrerillo de Santa Teresa

    Energy Technology Data Exchange (ETDEWEB)

    Casaravilla, G.; Chaer, R. [Instituto de Ingenieria Electrica, Facultad de Ingenieria, Universidad de la Republica, Montevideo (Uruguay)

    1997-12-31

    This paper describes the software Hybrid 95 and how it is used for the design of hybrid systems. As an application example some of the design stages are looked over (determination of the wind resource, simulations for sizing generation/storage and topology) of the Potrerillo installation. Taking into account the site clear ecological connotations, during the design consideration is made of the visual impact that represents the possible wind-generator, therefore several locations and wind-generator heights are studied, even arriving to the wind-generation elimination. [Espanol] Este trabajo describe el software Hybrid 95 y como se utiliza a los efectos del diseno de sistemas hibridos. Como ejemplo de aplicacion se recorren algunas de las etapas del diseno (determinacion del recurso eolico, simulaciones para el dimensionado de generacion/acumulacion y topologia) de la instalacion de Potrerillo. Teniendo en cuenta las claras connotaciones ecologistas del lugar, durante el diseno se tiene presente el impacto visual que representa el eventual aerogenerador por lo que se estudian diversas ubicaciones y alturas de aerogenerador, llegandose incluso a estudiar la eliminacion de la generacion eolica.

  14. Effects of methoprene and synergized pyrethrin aerosol applications on Tribolium castaneum (Herbst) populations

    Science.gov (United States)

    Experiments were performed to investigate the effects of horizontal transfer of the insect growth regulator (IGR) methoprene on confined populations of Tribolium castaneum (Herbst) either with or without hidden refugia. Multiple applications were made with the IGR alone or combined with synergized p...

  15. 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.)

  16. Modelling of organic aerosols over Europe (2002–2007 using a volatility basis set (VBS framework with application of different assumptions regarding the formation of secondary organic aerosol

    Directory of Open Access Journals (Sweden)

    D. Simpson

    2012-02-01

    Full Text Available A new organic aerosol (OA module has been implemented into the EMEP chemical transport model. Four different volatility basis set (VBS schemes have been tested in long-term simulations for Europe, covering the six years 2002–2007. Different assumptions regarding partitioning of primary OA (POA and aging of POA and secondary OA (SOA, have been explored. Model results are compared to filter measurements, AMS-data and source-apportionment studies, as well as to other model studies. The present study indicates that many different sources contribute significantly to OA in Europe. Fossil POA and oxidised POA, biogenic and anthropogenic SOA (BSOA and ASOA, residential burning of biomass fuels and wildfire emissions may all contribute more than 10% each over substantial parts of Europe. Simple VBS based OA models can give reasonably good results for summer OA but more observational studies are needed to constrain the VBS parameterisations and to help improve emission inventories. The volatility distribution of primary emissions is an important issue for further work. This study shows smaller contributions from BSOA to OA in Europe than earlier work, but relatively greater ASOA. BVOC emissions are highly uncertain and need further validation. We can not reproduce winter levels of OA in Europe, and there are many indications that the present emission inventories substantially underestimate emissions from residential wood burning in large parts of Europe.

  17. Setup and first airborne application of an aerosol optical properties package for the In-service Aircraft Global Observing System IAGOS.

    Science.gov (United States)

    Bundke, Ulrich; Freedman, Andrew; Herber, Andreas; Mattis, Ina; Berg, Marcel; De Faira, Julia; Petzold, Andreas

    2016-04-01

    different spectral information. The number of CAPS units to be used will depend on the size of the final electronic boards which are currently under development. The Sky OPC measures the size distribution theoretically up to 32 μm covering the relevant size information for calculation of aerosol optical properties. Because of the inlet cut off diameter of D50 = 3μm we are using the 16 channel mode in the range of 250 nm - 2.5 μm at 1 Hz resolution. In this presentation the setup of the IAGOS Aerosol package P2E is presented and characterized for pressure levels relevant for the planned application, down to cruising level of 150 hPa. In our aerosol lab we have tested the system against standard instrumentation with different aerosol test substances. In addition first results for airborne measurements are shown from a first airborne field campaign where in situ profiles are compared to LIDAR measurements over Bornholm (Denmark) and Lindenberg (Germany).

  18. 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.

  19. The impact of sequential ultra-low volume ground aerosol applications of malathion on the population dynamics of Aedes aegypti (L.).

    Science.gov (United States)

    Focks, D A; Kloter, K O; Carmichael, G T

    1987-05-01

    The efficacy of sequential, ultra-low volume ground aerosol applications of malathion at current U.S. label rates was evaluated as an emergency control measure for adult populations of Aedes aegypti (L.) in New Orleans, Louisiana. Replicates of 11 sequential aerosol treatments applied 12 hr apart during a 5.5-day period reduced mean adult captures and oviposition rates during the treatment period 73% and 75%, respectively. We hypothesize that oviposition was not completely suppressed because females with a developing egg burden remained sequestered during treatment periods or were more tolerant to the pesticide. We further concluded that adults could not be totally suppressed because of continued emergence. After treatment, adult densities recovered to pretreatment and control levels within approximately 1 week. A simulation study of the results suggested that, under the conditions of closely spaced housing and abundant vegetation that is typical of much of New Orleans, a single aerosol killed an average of 88% of the males and only 30% of the females present.

  20. Effects of bioethanol ultrasonic generated aerosols application on diesel engine performances

    Directory of Open Access Journals (Sweden)

    Mariasiu Florin

    2015-01-01

    Full Text Available In this paper the effects of an experimental bioethanol fumigation application using an experimental ultrasound device on performance and emissions of a single cylinder diesel engine have been experimentally investigated. Engine performance and pollutant emissions variations were considered for three different types of fuels (biodiesel, biodiesel-bioethanol blend and biodiesel and fumigated bioethanol. Reductions in brake specific fuel consumption and NOx pollutant emissions are correlated with the use of ultrasonic fumigation of bioethanol fuel, comparative to use of biodiesel-bioethanol blend. Considering the fuel consumption as diesel engine’s main performance parameter, the proposed bioethanol’s fumigation method, offers the possibility to use more efficient renewable biofuels (bioethanol, with immediate effects on environmental protection.

  1. Mística e profecia na espiritualidade cristã. O testemunho de Santa Teresa de Jesus (Mysticism and prophecy in Christian spirituality. The testimony of Saint Teresa of Jesus - DOI: 10.5752/P.2175-5841.2012v10n27p757

    Directory of Open Access Journals (Sweden)

    Lúcia Pedrosa-Pádua

    2012-10-01

    Full Text Available O presente artigo trata da inter-relação entre mística e profecia na espiritualidade cristã. Pretende enfrentar dualismos, encontrados no passado e também no presente do cristianismo, entre ambos os termos. Apresenta o testemunho de Santa Teresa de Ávila como caminho de superação da dicotomia entre mística e profecia através de uma integração processual. O fundamento da necessária relação entre os termos em questão é a própria existência de Jesus de Nazaré, que pode ser considerada profético-mística. Isto significa que há uma inter-relação entre oração e ação, contemplação e missão. No entanto, o sujeito moderno e pós-moderno apresenta dificuldades nesta integração, como o deixar-se transformar pela oração, superando a tendência ao controle e à eficácia. Santa Teresa de Jesus, neste contexto, é testemunho de mística e profecia, mediadas por um discernimento que passa por percepções cotidianas. O livro das Fundações é privilegiado para ilustrar este discernimento. Palavras-chave: Mística, profecia, discernimento, Santa Teresa de Jesus. Abstract This article deals with the interrelationship between mysticism and prophecy in Christian spirituality. It intends to face the dualism between both terms, present not only in early, but also in present-day Christianity. It presents Saint Teresa of Ávila as a testimony of how to overcome the dichotomy between mysticism and prophecy by means of step by step integration. The basis for the necessary relationship between the terms being studied is the actual existence of Jesus of Nazareth, which can be considered prophetic and mystic. In other words, prayer and action, contemplation and mission are strictly related. However, the modern and postmodern person has difficulties in dealing with this type of integration, such as opening himself to transformation by prayer, then overcoming the tendency to be in control and to be efficient. Saint Teresa of Jesus, in this

  2. Inductively coupled plasma spectrometry: Noise characteristics of aerosols, application of generalized standard additions method, and Mach disk as an emission source

    Energy Technology Data Exchange (ETDEWEB)

    Luan, Shen [Iowa State Univ., Ames, IA (United States)

    1995-10-06

    This dissertation is focused on three problem areas in the performance of inductively coupled plasma (ICP) source. The noise characteristics of aerosols produced by ICP nebulizers are investigated. A laser beam is scattered by aerosol and detected by a photomultiplier tube and the noise amplitude spectrum of the scattered radiation is measured by a spectrum analyzer. Discrete frequency noise in the aerosol generated by a Meinhard nebulizer or a direct injection nebulizer is primarily caused by pulsation in the liquid flow from the pump. A Scott-type spray chamber suppresses white noise, while a conical, straight-pass spray chamber enhances white noise, relative to the noise seen from the primary aerosol. Simultaneous correction for both spectral interferences and matrix effects in ICP atomic emission spectrometry (AES) can be accomplished by using the generalized standard additions method (GSAM). Results obtained with the application of the GSAM to the Perkin-Elmer Optima 3000 ICP atomic emission spectrometer are presented. The echelle-based polychromator with segmented-array charge-coupled device detectors enables the direct, visual examination of the overlapping lines Cd (1) 228.802 nm and As (1) 228.812 nm. The slit translation capability allows a large number of data points to be sampled, therefore, the advantage of noise averaging is gained. An ICP is extracted into a small quartz vacuum chamber through a sampling orifice in a water-cooled copper plate. Optical emission from the Mach disk region is measured with a new type of echelle spectrometer equipped with two segmented-array charge-coupled-device detectors, with an effort to improve the detection limits for simultaneous multielement analysis by ICP-AES.

  3. Polarimetric method of estimation of vertical aerosol distribution in application to observations of ozone and NO2

    Science.gov (United States)

    Elansky, Nikolay F.; Kadyshevich, Elena A.; Savastyuk, Vladimir V.

    1994-01-01

    The degree of polarization of skylight at the zenith during twilight depends on the aerosol content in the atmosphere. The long-term observations at the high-mountain research station 'Kislovodsk' (North Caucasus) have shown that the variation of the degree of polarization after the eruption of the El Chichon volcano can serve as the effective parameter characterizing the vertical aerosol stratification in the atmosphere. The results of the measurements are confirmed by the numerical calculations. The algorithm of the retrieval of the vertical aerosol distribution on the base of the measurements of the degree of polarization is proposed. This method can be applied for the increasing of the precision of O3, NO2, and other gas content measurements.

  4. Entrevista: Teresa Ramos Interview: Teresa Ramos

    Directory of Open Access Journals (Sweden)

    2007-07-01

    Full Text Available A aula inaugural de Tereza Ramos, proferida no início do ano letivo na Escola Politécnica de Saúde Joaquim Venâncio/Fiocruz, no Rio de Janeiro, constituiu uma autêntica lição de participação política. Agente comunitário de saúde (ACS desde 1978, atualmente Tereza é a presidente da Confederação Nacional de Agentes Comunitários de Saúde, que reúne as federações estaduais, abrangendo dez estados brasileiros, algumas anteriores ao Programa de Agentes Comunitários de Saúde (Pacs. Nesta entrevista¹, concedida um dia antes da palestra, Tereza conta um pouco sobre a luta protagonizada pelos agentes comunitários de saúde em busca de 'desprecarização' de seu trabalho. Essa luta culminou na edição da emenda constitucional nº 51, de fevereiro de 2006, e da lei 11.350, de outubro de 2006, que regulamenta a emenda, marcos legais de amparo à profissão de agente comunitário de saúde e exemplo de exercício de cidadania de Tereza e do grupo de ACS liderado por ela. Militante histórica do setor saúde, que cruzou o caminho de Sergio Arouca na VIII Conferência Nacional de Saúde, também opina sobre a formação que os ACS vêm recebendo em curso técnico. Essa formação é considerada fundamental, junto com a 'desprecarização' dos vínculos e a regularização do acesso, para a efetiva profissionalização e reconhecimento dos direitos desses trabalhadores.The inaugural class given by Tereza Ramos to kick the school year off at the Joaquim Venâncio/Fiocruz Polytechnic Health School, in Rio de Janeiro, was a genuine lesson in political participation. A community health agent (CHA since 1978, Tereza is currently the president of the National Community Health Agent Confederation, which brings state federations from ten Brazilian states, a few of which existed before the Community Health Agent Program (CHAP, together. In this interview, granted a day before the lecture, Tereza talks a little about the community health agents' battle in search of reducing the precarious nature of their work. This battle culminated in constitutional amendment number 51, dated February 2006, and in law 11.350, dated October 2006, which regulates the amendment, the legal guidelines that support the community health agent's profession and is an example of the exercise of citizenship not only by Tereza, but of the group of CHAs she leads. A historical heath sector militant, who crossed paths with Servio Arouca in the 8th National Health Conference, Tereza also opines on the training the CHAs have been getting in technical courses. This training is considered as vitally important, alongside the elimination of the precarious nature of job ties and regularizing access, for these workers' actual professionalization and to the acknowledgement of their rights.

  5. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963); Etude du comportement dcs aerosols radioactifs artificiels. Applications a quelques problemes de circulation atmospherique (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-11-15

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author) [French] L'objectif de ce travail consiste a examiner le comportement des aerosols radioactifs introduits dans l'atmosphere par les explosions nucleaires, pour en deduire les lois les plus generals de la circulation et diffusion atmospheriques. Apres avoir dresse un tableau d'ensemble des aerosols radioactifs presents, on examine la validite et la precision des methodes de mesure de leur concentration, au niveau du sol et en haute atmosphere, ainsi que de leur depot a la surface du sol. On met ainsi en evidence l'existence d'une barriere equatoriale tropospherique; l'aspect discontinu et saisonnier des transferts stratosphere-troposphere; le role des precipitations et de l'auto-filtration seche, dans les processus de nettoyage de la basse atmosphere. Ces etudes permettent de decrire le comportement general des poussieres d'origine stratospherique et d'ameliorer le bilan de la contamination radioactive du globe. (auteur)

  6. 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

  7. 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

  8. Application of both a physical theory and statistical procedure in the analyses of an in vivo study of aerosol deposition

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, K.H.; Swift, D.L. [Johns Hopkins Univ., Baltimore, MD (United States); Yang, Y.H. [Univ. of North Carolina, Chapel Hill, NC (United States)] [and others

    1995-12-01

    Regional deposition of inhaled aerosols in the respiratory tract is a significant factor in assessing the biological effects from exposure to a variety of environmental particles. Understanding the deposition efficiency of inhaled aerosol particles in the nasal and oral airways can help evaluate doses to the extrathoracic region as well as to the lung. Dose extrapolation from laboratory animals to humans has been questioned due to significant physiological and anatomical variations. Although human studies are considered ideal for obtaining in vivo toxicity information important in risk assessment, the number of subjects in the study is often small compared to epidemiological and animal studies. This study measured in vivo the nasal airway dimensions and the extrathoracic deposition of ultrafine aerosols in 10 normal adult males. Variability among individuals was significant. The nasal geometry of each individual was characterized at a resolution of 3 mm using magnetic resonance imaging (MRI) and acoustic rhinometry (AR). The turbulent diffusion theory was used to describe the nonlinear nature of extrathoracic aerosol deposition. To determine what dimensional features of the nasal airway were responsible for the marked differences in particle deposition, the MIXed-effects NonLINear Regression (MIXNLIN) procedure was used to account for the random effort of repeated measurements on the same subject. Using both turbulent diffusion theory and MIXNLIN, the ultrafine particle deposition is correlated with nasal dimensions measured by the surface area, minimum cross-sectional area, and complexity of the airway shape. The combination of MRI and AR is useful for characterizing both detailed nasal dimensions and temporal changes in nasal patency. We conclude that a suitable statistical procedure incorporated with existing physical theories must be used in data analyses for experimental studies of aerosol deposition that involve a relatively small number of human subjects.

  9. The “Truth about White Slavery”. Présentation d’une enquête réalisée par Teresa Billington-Greig pour The English Review (juin 1913 The “Truth about White Slavery”. Presentation of an Investigation carried out by Teresa Billington-Greig for The English Review (June 1913

    Directory of Open Access Journals (Sweden)

    Christine Machiels

    2011-02-01

    Full Text Available En 1913, une féministe anglaise, Teresa Billington-Greig, publie dans The Eng­lish Review les résultats d’une enquête qu’elle a réalisée sur la traite des blan­ches. Alors que cette question suscite une agitation exceptionnelle (moral panic, sa recherche fait, à bien des égards, et au vu de la littérature de l’épo­que, figure d’exception. Symbole de toutes les angoisses d’une société victo­rienne en pleine mutation, la traite suscite de grandes émotions, auxquelles Teresa Billington-Greig oppose une réflexion basée sur l’étude des faits et la critique. Par son travail d’investigation inédit, qui répond aux critères de la re­cherche empirique, elle plaide plus largement pour une science sociale au ser­vice des réformes.In 1913, an English feminist, Teresa Billington-Greig, published the results of an enquiry she carried out on white slavery in The English Review. Whereas the question gave rise to moral panic, her research was, in many regards, and compared to the literature of the time, exceptional. The very symbol of all the anxieties of a Victorian society undergoing major changes, white slavery gave rise to high emotions, which Teresa Billington-Greig countered by reflection based on her study of the facts and criticism. By her unprecedented investigational work, which meets the criteria of empirical research, she launched a wider plea for a social science at the service of reforms.

  10. Assessment and management of debris-flow risk in a tropical high-mountain catchment in Santa Teresa, Peru

    Science.gov (United States)

    Frey, Holger; Buis, Daniel; Huggel, Christian; Bühler, Yves; Choquevilca, Walter; Fernandez, Felipe; García, Javier; Giráldez, Claudia; Loarte, Edwin; Masias, Paul; Portocarreo, César; Price, Karen; Walser, Marco

    2015-04-01

    The local center of Santa Teresa (Cusco Region, Peru, 7 km northwest of the ruins of Machu Picchu) has been affected by several large debris-flow events in the recent past. In January and February 1998, three events of extreme magnitudes with estimated total volumes of several tens of millions cubic meters each, caused the destruction of most parts of the municipality and resulted in a resettlement of the town on higher grounds. Additionally, several settlements further upstream, as well valuable infrastructure such as bridges, a railway, and a hydropower plant, were destroyed. Some events were related to large-scale slope instabilities and landslide processes in glacial sediments that transformed into highly mobile debris flows. However, the exact trigger mechanisms are still not entirely clear, and the potential role of glacial lakes for past and future mass flows remains to be analyzed. Here we applied RAMMS (RApid Mass Movement System), a physically based dynamic model, to reconstruct one of the 1998 events in the Sacsara catchment using the ASTER Global Digital Elevation Model (ASTER GDEM) with 30 m spatial resolution and a photogrammetric DEM compiled from ALOS PRISM data with 6 m spatial resolution. A sensitivity analysis for various model parameters such as friction and starting conditions was performed, along with an assessment of potential trigger factors. Based on these results, further potential debris-flows for this catchment were modeled, including outburst scenarios of several glacial lakes. In combination with a vulnerability analysis, these hazard scenarios were then incorporated in a qualitative risk analysis. To further reduce the risk for the local communities, technical risk sheets were elaborated for each of the 17 local settlements in the catchment. Furthermore an Early Warning System (EWS) has been designed. The modular structure of the EWS aims at a first step to install an inexpensive but efficient system to detect debris-flow type mass

  11. Servando Teresa de Mier y sus polémicas cartas a la Ilustración española

    OpenAIRE

    Mariana Rosetti

    2012-01-01

    El presente artículo analiza la particular modulación de la figura del letrado criollo que desplegó Servando Teresa de Mier en sus cartas dirigidas al historiador Juan Bautista Muñoz y al periodista sevillano José María Blanco White. Estas cartas configuraron un moderno locus de enunciación letrado que le permitió a Mier editar el saber ilustrado español tanto sobre la tradición religiosa novohispana como sobre la capacidad política de los americanos frente a la crisis institucional suscitada...

  12. Santa Teresa of Jesus as Example for the Novo Hispanic Mystics. The Work of Alonso Ramos about Catarina de San Juan

    OpenAIRE

    Gisela von Wobeser

    2016-01-01

    The life and work of Santa Teresa of Jesus had a great influence on the New Spain spiritual atmosphere by enabling a more intimate and direct relationship of women with God and contribute to the proliferation of nuns and beatified. In the Wonders of the Omnipotence and Miracles of the Grace in the life of the Venerable Servant of God Catharina of San Joan, Alonso Ramos writes the biography of Catarina of San Juan, a free slave considered saint, to whom in many passages compares with Santa Ter...

  13. Demonstration of the Applicability of Novel Photoacoustic Aerosol Monitor for Optical Absorption Coefficient Determination. Laboratory and Field Test.

    Science.gov (United States)

    Ajtai, T.; Schnaiter, M.; Linke, C.; Vragel, M.; Filep, Á.; Fődi, L.; Motika, G.; Bozóki, Z.; Szabó, G.

    2009-04-01

    Despite of its importance, the possibilities to determine the direct radiative forcing by atmospheric aerosols is very limited due to lack of the reliable on-line instruments. Therefore there is an increasing concern for novel methods promising more accurate and reliable results in this field. The accuracy and reliability of the available on-line instruments like SP2 (Single Particle Soot Photometer), MAAP (Multi Angle Absorption Photometer), are limited by the weakness of the spectral resolution or the sampling artefact of filter matrix during the light attenuation measurement on the deposited filter. These methods neither suitable for direct determination of the light absorption by aerosols nor dispose the capability of the source apportionment. In this work we present a novel photoacoustic based instrument for direct light absorption measurements in the atmosphere and demonstrate the suitability of that both in laboratory and field circumstances. We have developed a novel Multi Wavelength PhotoAcoustic System (WaSul-MuWaPas) based on the diode laser pumped, high repetition rate, Q-switched Nd:YAG laser and its frequency converted harmonics for direct determination of light absorption by aerosols. This instrument has designed to make in situ measurements at four different wavelengths simultaneously from the NIR to the UV wavelength range (1064nm, 532nm, 355nm, 266nm). The Wasul-MuWaPas measures directly the optical absorption coefficient on airborne particles, not belong to the integrated plate type technique (filter-free operation), operating at wide wavelength range (source apportionment possibilities), due to the possibilities of the wavelength independent cell constant determination the measurement method is absolute. Because of these the Wasul-MuWaPas system may become one of the best candidate for absorption measurements of various atmospheric aerosols such as black carbon, mineral dust, and secondary organic and inorganic aerosols as well as for source

  14. Size-Time-Composition Resolved Study of Aerosols Across El Paso, Texas in Fall 2008

    Science.gov (United States)

    Cahill, T. A.; Gill, T. E.; Pingitore, N. E.; Olvera, H. A.; Clague, J. W.; Barnes, D. E.; Perry, K. D.; Li, W.; Amaya, M. A.

    2009-12-01

    Systematic variations in the absolute amounts, size and composition of airborne particulate matter (PM) across the El Paso, Texas metropolitan area may differentially impact the respiratory status (e.g., asthma) and overall health of the local population. To understand these variations, we collected size-time resolved samples of PM with DRUM samplers during a one-month period in late autumn 2008 at three sites along a NW-SE (roughly upwind-downwind) transect across El Paso’s airshed. The DRUM sampler is a rotating-drum impactor separating and collecting aerosols on Mylar strips mounted on the drums, in 8 size stages from 10 μm to Mexico (a minimally developed area NW of El Paso, at the edge of a sparsely-inhabited expanse of the Chihuahuan Desert), at the edge of the University of Texas- El Paso (UTEP) campus (in the urban core of El Paso), and at Socorro, Texas (a suburban area in the valley of the Rio Grande, SE of the urban core). Results illustrate sharp excursions in mass and element concentrations in aerosol-laden periods lasting from several hours to several days, associated with stagnant air, inversions, smoke events, dust/high wind/frontal passage, and/or daily traffic patterns, punctuated by several periods of reduced aerosol levels after Pacific frontal passages. Mass and absorption data show an increasing influence of carbonaceous (absorbing) aerosols with decreasing particle size ~1 μm. Calcium/silicon ratios were high (>1), especially in coarser stages and during high wind events, reflecting wind erosion of the Chihuahuan Desert’s calcareous soils. Concentrations of chlorine, silicon, calcium, coarse potassium, and lead increased during high wind events, while fine chlorine and fine potassium increased during smoke events, and zinc, sulfur, and fine potassium concentrations increased during inversion/stagnation events. Concentrations of most elements, especially crustal elements, increased overall from Santa Teresa to UTEP to Socorro, reflecting

  15. 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...

  16. Effect of Terrestrial and Marine Organic Aerosol on Regional and Global Climate: Model Development, Application, and Verification with Satellite Data

    Energy Technology Data Exchange (ETDEWEB)

    Meskhidze, Nicholas; Zhang, Yang; Kamykowski, Daniel

    2012-03-28

    In this DOE project the improvements to parameterization of marine primary organic matter (POM) emissions, hygroscopic properties of marine POM, marine isoprene derived secondary organic aerosol (SOA) emissions, surfactant effects, new cloud droplet activation parameterization have been implemented into Community Atmosphere Model (CAM 5.0), with a seven mode aerosol module from the Pacific Northwest National Laboratory (PNNL)'s Modal Aerosol Model (MAM7). The effects of marine aerosols derived from sea spray and ocean emitted biogenic volatile organic compounds (BVOCs) on microphysical properties of clouds were explored by conducting 10 year CAM5.0-MAM7 model simulations at a grid resolution 1.9° by 2.5° with 30 vertical layers. Model-predicted relationship between ocean physical and biological systems and the abundance of CCN in remote marine atmosphere was compared to data from the A-Train satellites (MODIS, CALIPSO, AMSR-E). Model simulations show that on average, primary and secondary organic aerosol emissions from the ocean can yield up to 20% increase in Cloud Condensation Nuclei (CCN) at 0.2% Supersaturation, and up to 5% increases in droplet number concentration of global maritime shallow clouds. Marine organics were treated as internally or externally mixed with sea salt. Changes associated with cloud properties reduced (absolute value) the model-predicted short wave cloud forcing from -1.35 Wm-2 to -0.25 Wm-2. By using different emission scenarios, and droplet activation parameterizations, this study suggests that addition of marine primary aerosols and biologically generated reactive gases makes an important difference in radiative forcing assessments. All baseline and sensitivity simulations for 2001 and 2050 using global-through-urban WRF/Chem (GU-WRF) were completed. The main objective of these simulations was to evaluate the capability of GU-WRF for an accurate representation of the global atmosphere by exploring the most accurate

  17. Historical (1850–2000 gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application

    Directory of Open Access Journals (Sweden)

    J.-F. Lamarque

    2010-02-01

    Full Text Available We present and discuss a new dataset of gridded emissions covering the historical period (1850–2000 in decadal increments at a horizontal resolution of 0.5° in latitude and longitude. The primary purpose of this inventory is to provide consistent gridded emissions of reactive gases and aerosols for use in chemistry model simulations needed by climate models for the Climate Model Intercomparison Program #5 (CMIP5 in support of the Intergovernmental Panel on Climate Change (IPCC Fifth Assessment Report (AR5. Our best estimate for the year 2000 inventory represents a combination of existing regional and global inventories to capture the best information available at this point; 40 regions and 12 sectors are used to combine the various sources. The historical reconstruction of each emitted compound, for each region and sector, is then forced to agree with our 2000 estimate, ensuring continuity between past and 2000 emissions. Simulations from two chemistry-climate models is used to test the ability of the emission dataset described here to capture long-term changes in atmospheric ozone, carbon monoxide and aerosol distributions. The simulated long-term change in the Northern mid-latitudes surface and mid-troposphere ozone is not quite as rapid as observed. However, stations outside this latitude band show much better agreement in both present-day and long-term trend. The model simulations indicate that the concentration of carbon monoxide is underestimated at the Mace Head station; however, the long-term trend over the limited observational period seems to be reasonably well captured. The simulated sulfate and black carbon deposition over Greenland is in very good agreement with the ice-core observations spanning the simulation period. Finally, aerosol optical depth and additional aerosol diagnostics are shown to be in good agreement with previously published estimates and observations.

  18. Historical (1850–2000 gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application

    Directory of Open Access Journals (Sweden)

    J.-F. Lamarque

    2010-08-01

    Full Text Available We present and discuss a new dataset of gridded emissions covering the historical period (1850–2000 in decadal increments at a horizontal resolution of 0.5° in latitude and longitude. The primary purpose of this inventory is to provide consistent gridded emissions of reactive gases and aerosols for use in chemistry model simulations needed by climate models for the Climate Model Intercomparison Program #5 (CMIP5 in support of the Intergovernmental Panel on Climate Change (IPCC Fifth Assessment report (AR5. Our best estimate for the year 2000 inventory represents a combination of existing regional and global inventories to capture the best information available at this point; 40 regions and 12 sectors are used to combine the various sources. The historical reconstruction of each emitted compound, for each region and sector, is then forced to agree with our 2000 estimate, ensuring continuity between past and 2000 emissions. Simulations from two chemistry-climate models are used to test the ability of the emission dataset described here to capture long-term changes in atmospheric ozone, carbon monoxide and aerosol distributions. The simulated long-term change in the Northern mid-latitudes surface and mid-troposphere ozone is not quite as rapid as observed. However, stations outside this latitude band show much better agreement in both present-day and long-term trend. The model simulations indicate that the concentration of carbon monoxide is underestimated at the Mace Head station; however, the long-term trend over the limited observational period seems to be reasonably well captured. The simulated sulfate and black carbon deposition over Greenland is in very good agreement with the ice-core observations spanning the simulation period. Finally, aerosol optical depth and additional aerosol diagnostics are shown to be in good agreement with previously published estimates and observations.

  19. 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...

  20. A critical examination of spatial biases between MODIS and MISR aerosol products – application for potential AERONET deployment

    Directory of Open Access Journals (Sweden)

    T. F. Eck

    2011-12-01

    Full Text Available AErosol RObotic NETwork (AERONET data are the primary benchmark for evaluating satellite-retrieved aerosol properties. However, despite its extensive coverage, the representativeness of the AERONET data is rarely discussed. Indeed, many studies have shown that satellite retrieval biases have a significant degree of spatial correlation that may be problematic for higher-level processes or inverse-emissions-modeling studies. To consider these issues and evaluate relative performance in regions of few surface observations, cross-comparisons between the Aerosol Optical Depth (AOD products of operational MODIS Collection 5.1 Dark Target (DT and operational MODIS Collection 5.1 Deep Blue (DB with MISR version 22 were conducted. Through such comparisons, we can observe coherent spatial features of the AOD bias while sidestepping the full analysis required for determining when or where either retrieval is more correct. We identify regions where MODIS to MISR AOD ratios were found to be above 1.4 and below 0.7. Regions where lower boundary condition uncertainty is likely to be a dominant factor include portions of Western North America, the Andes mountains, Saharan Africa, the Arabian Peninsula, and Central Asia. Similarly, microphysical biases may be an issue in South America, and specific parts of Southern Africa, India Asia, East Asia, and Indonesia. These results help identify high-priority locations for possible future deployments of both in situ and ground based remote sensing measurements. The Supplement includes a kml file.

  1. A Critical Examination of Spatial Biases Between MODIS and MISR Aerosol Products - Application for Potential AERONET Deployment

    Science.gov (United States)

    Shi, Y.; Zhang, J.; Reid, J. S.; Hyer, E. J.; Eck, T. F.; Holben, B. N.; Kahn, R. A.

    2011-01-01

    AErosol RObotic NETwork (AERONET) data are the primary benchmark for evaluating satellite-retrieved aerosol properties. However, despite its extensive coverage, the representativeness of the AERONET data is rarely discussed. Indeed, many studies have shown that satellite retrieval biases have a significant degree of spatial correlation that may be problematic for higher-level processes or inverse-emissions-modeling studies. To consider these issues and evaluate relative performance in regions of few surface observations, cross-comparisons between the Aerosol Optical Depth (AOD) products of operational MODIS Collection 5.1 Dark Target (DT) and operational MODIS Collection 5.1 Deep Blue (DB) with MISR version 22 were conducted. Through such comparisons, we can observe coherent spatial features of the AOD bias while side-stepping the full analysis required for determining when or where either retrieval is more correct. We identify regions where MODIS to MISR AOD ratios were found to be above 1.4 and below 0.7. Regions where lower boundary condition uncertainty is likely to be a dominant factor include portions of Western North America, the Andes mountains, Saharan Africa, the Arabian Peninsula, and Central Asia. Similarly, microphysical biases may be an issue in South America, and specific parts of Southern Africa, India Asia, East Asia, and Indonesia. These results help identify high-priority locations for possible future deployments of both in situ and ground based remote sensing measurements. The Supplement includes a km1 file.

  2. Evaluation of the applicability of the MOUDI impactor for aerosol collections with subsequent multielement analysis by PIXE

    Energy Technology Data Exchange (ETDEWEB)

    Maenhaut, W.; Ducastel, G. (Inst. for Nuclear Sciences, Gent (Belgium)); Hillamo, R.E.; Pakkanen, T.A. (Finnish Meteorological Inst., Helsinki (Finland))

    1993-04-01

    The micro-orifice uniform deposit impactor (MOUDI) is an 8-stage impactor with cut-sizes down to 0.056 [mu]m and which allegedly provides uniform aerosol deposits for the various stages. In the present study it was examined how uniform the aerosol deposits really are for each impaction plate, and whether the uniformity is sufficient for a straightforward PIXE analysis. This was done by collecting several samples of ambient aerosol with the MOUDI and by determining the deposition pattern of various elements on the foils through a linear PIXE scan across each impaction foil. It was found that the deposits are far from uniform at the millimeter level for the stage numbers up to 6. Despite this, concentration data can easily be obtained by PIXE from such samples, provided that the analyzed area is carefully selected and appropriate correction factors for the nonuniformity are employed. Some size distribution data are presented. A comparison is also made of the size distribution data and detection limits that result from employing the MOUDI in combination with PIXE with those obtainable by PIXE analysis of some other types of cascade impactors. (orig.).

  3. Development and validation of a size-resolved particle dry deposition scheme for applications in aerosol transport models

    Directory of Open Access Journals (Sweden)

    A. Petroff

    2010-08-01

    Full Text Available A size-resolved particle dry deposition scheme is developed, which has been designed for inclusion in large-scale air quality and climate models, where the size distribution and fate of the atmospheric aerosol is of concern. The "resistance" structure is similar to what is proposed by Zhang et al. (2001, 2003, while a new "surface" deposition velocity (or surface resistance is derived by simplification of a one-dimensional aerosol transport model (Petroff et al., 2008b, 2009. Collection efficiencies are given for the 26 Land Use Categories that decribe the earth surface. Validation of this model with existing measurements is performed on desert, grass, coniferous forest and liquid water surfaces. A comparison of this model with measurements on snow and ice is also given. Even though a qualitative agreement is reached, further size-segegated measurements are needed in order to confirm the model accuracy on this surface. The present analytical model provides more accurate predictions of the aerosol deposition on these surfaces than previous models.

  4. Cuerpos místicos, almas ascéticas. Regulaciones del espíritu en la experiencia de Teresa de Ávila (1515-1582.

    Directory of Open Access Journals (Sweden)

    Mònica Balltondre

    2009-11-01

    Full Text Available En esta tesis se investiga la antropología que subyace a la espiritualidad mística femenina de mediados del siglo XVI castellano, de la mano de Teresa de Ávila, conocida como Teresa de Jesús. Ella construyó una forma espiritual de vivirse que le permitió encuadrar sus experiencias a partir de tradiciones teológicas, como la mística, y de otros saberes como la filosofía natural y la medicina de su tiempo. Se examinan para ver cómo conceptualizó sus relaciones sobrenaturales y qué le aportaron en la construcción de sí misma. Por ejemplo, analizo sus propuestas de oración y meditación para entender la construcción psíquica que había detrás; los significados teológicos que atribuyó a las enfermedades de su cuerpo; su uso del dolor, etc. Además, exploro cómo funcionó su programa espiritual en sus fundaciones. Al revisar las implicaciones que estos discursos espirituales tuvieron en la forma de determinar procesos vivenciales, dentro de su producción histórica, damos cuenta de algunas de las categorías y prácticas que configuraron un cierto sujeto moderno.

  5. El espíritu de la verdad en Teresa de Jesús y Edith Stein. Testimonio y mística

    Directory of Open Access Journals (Sweden)

    Silvia Julia Campana

    2015-04-01

    Full Text Available Teresa de Jesús y Edith Stein son testigos del Amor desbordante, embriagadas en el perfume de la Verdad que las reúne en una búsqueda común. “Cuando venga el Espíritu de la Verdad, él los introducirá en toda la verdad”. Ambas son transformadas, desde la hondura del Espíritu que las habita, en testimonio de la libertad que brota de la Verdad que sale al encuentro; en testimonio de la autenticidad de una vida entregada al Otro/otros; en testimonio de un secreto que las habita, las transforma y las conduce hasta la ofrenda de la propia vida. Porque el testimonio, como afirma Ricoeur, “es también el compromiso de un corazón puro y un compromiso hasta la muerte. Pertenece al destino trágico de la verdad”. Teresa de Jesús ingresa a la vida de la joven filósofa Edith Stein a través de la palabra, del “poema” que relata su propia vida y le descubre un mundo nuevo. Biografía que transforma otra biografía y nos permite hoy reunirlas en la comunidad del testimonio y la mística.

  6. Empowerment for Ladies: readings of Milady of Myself by Maria Teresa Horta and Milady of What? by Ana Luísa Amaral

    Directory of Open Access Journals (Sweden)

    Fabio Mario da Silva

    2013-10-01

    Full Text Available The reunion with the “self”, the “dressing up” of self, in an innermost representation of the “feminine/female soul”, bringing some aspects of everyday-life as important references, allows Maria Teresa Horta and Ana Luísa Amaral to construct poetry in which the feminine lyrical self takes not only possession of what she observes, but also the power to make decisions about her life, as “lady” and “owner” of herself, in a speech free of patriarchal oppression. In this article we will analyze how various “ladies” are built in these two works, underlining that Minha Senhora de Mim is configured as a milestone of Portuguese poetry by women, opening a rift to restore possession of the speech (and of the body to women without sociocultural impediments that might limit the work of the woman writer; and how Ana Luísa Amaral, paraphrasing Maria Teresa Horta in an obvious homage in Minha Senhora de Quê builds a work with its own identity within a different feminist perspective.

  7. Aerosol Dynamics – Mathematical Formulation, Numerical Solution

    OpenAIRE

    Pušman, Jan

    2012-01-01

    Mathematical and computer modeling of aerosols is used in a wide range of applications including atmospheric physics and chemistry, environmental protection, nuclear safety and industrial applications such as the production of nanomaterials. The aim of this work is twofold. We present a closer look at some aspects of mathematical modeling of aerosols as sub-discipline of continuum mechanics. We provide an overview of common methods and we discuss limitations on their applicability. The long-...

  8. A generalized formulation for downscaling data based on Fourier Transform and inversion: Mathematical rationale and application to the Max-Planck-Institute aerosol climatology data

    Science.gov (United States)

    Zhang, Taiping; Stackhouse, Paul W.; Gupta, Shashi K.; Cox, Stephen J.; Mikovitz, J. Colleen

    2017-02-01

    Occasionally, a need arises to downscale a time series of data from a coarse temporal resolution to a finer one, a typical example being from monthly means to daily means. For this case, daily means derived as such are used as inputs of climatic or atmospheric models so that the model results may exhibit variance on the daily time scale and retain the monthly mean of the original data set without an abrupt change from the end of one month to the beginning of the next. Different methods have been developed which often need assumptions, free parameters and the solution of simultaneous equations. Here we derive a generalized formulation by means of Fourier transform and inversion so that it can be used to directly compute daily means from a series of an arbitrary number of monthly means. The formulation can be used to transform any coarse temporal resolution to a finer one. From the derived results, the original data can be recovered almost identically. As a real application, we use this method to derive the daily counterpart of the MAC-v1 aerosol climatology that provides monthly mean aerosol properties for 18 shortwave bands and 12 longwave bands for the years from 1860 to 2100. The derived daily means are to be used as inputs of the shortwave and longwave algorithms of the NASA GEWEX SRB project.

  9. 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

  10. Issues in Data Fusion for Satellite Aerosol Measurements for Applications with GIOVANNI System at NASA GES DISC

    Science.gov (United States)

    Gopalan, Arun; Zubko, Viktor; Leptoukh, Gregory G.

    2008-01-01

    We look at issues, barriers and approaches for Data Fusion of satellite aerosol data as available from the GES DISC GIOVANNI Web Service. Daily Global Maps of AOT from a single satellite sensor alone contain gaps that arise due to various sources (sun glint regions, clouds, orbital swath gaps at low latitudes, bright underlying surfaces etc.). The goal is to develop a fast, accurate and efficient method to improve the spatial coverage of the Daily AOT data to facilitate comparisons with Global Models. Data Fusion may be supplemented by Optimal Interpolation (OI) as needed.

  11. 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.

  12. Fiel reproducción de Santa Teresa de Jesús y Cristo "El Amarrado" de Gregorio Fernández a base de Tecnologías 3D

    Directory of Open Access Journals (Sweden)

    Marteyn van Gasteren

    2013-05-01

    Saint Teresa at Ávila. The reproduction is carried out according a very innovative process of 3D digitization with two scanners combined with CNC robot milling, complemented by traditional techniques. This process results in a very high degree of faithfulness of the replicas.

  13. Aerosol assisted synthesis of hierarchical tin–carbon composites and their application as lithium battery anode materials

    KAUST Repository

    Guo, Juchen

    2013-01-01

    We report a method for synthesizing hierarchically structured tin-carbon (Sn-C) composites via aerosol spray pyrolysis. In this method, an aqueous precursor solution containing tin(ii) chloride and sucrose is atomized, and the resultant aerosol droplets carried by an inert gas are pyrolyzed in a high-temperature tubular furnace. Owing to the unique combination of high reaction temperature and short reaction time, this method is able to achieve a hetero-structure in which small Sn particles (15 nm) are uniformly embedded in a secondary carbon particle. This procedure allows the size and size distribution of the primary Sn particles to be tuned, as well as control over the size of the secondary carbon particles by addition of polymeric surfactant in the precursor solution. When evaluated as anode materials for lithium-ion batteries, the resultant Sn-C composites demonstrate attractive electrochemical performance in terms of overall capacity, electrochemical stability, and coulombic efficiency. © 2013 The Royal Society of Chemistry.

  14. A new comprehensive approach to characterizing carbonaceous aerosol with an application to wintertime Fresno, California PM2.5

    Science.gov (United States)

    Herckes, P.; Leenheer, J.A.; Collett, J.L.

    2007-01-01

    Fine particulate matter (PM2.5) samples were collected during a three week winter period in Fresno (CA). A composite sample was characterized by isolating several distinct fractions and characterizing them by infrared and nuclear magnetic resonance (NMR) spectroscopy. More than 80% of the organic matter in the aerosol samples was recovered and characterized. Only 35% of the organic matter was water soluble with another third soluble in dichloromethane and the remainder insoluble. Within the isolated water soluble material, hydrophobic acid and hydrophilic acids plus neutrals fractions contained the largest amounts of carbon. The hydrophobic acids fraction appears to contain significant amounts of lignin type structures, spectra of the hydrophilic acids plus neutrals fraction are indicative of carbohydrates and secondary organic material. The dichloromethane soluble fraction contains a variety of organic compound families typical of many previous studies of organic aerosol speciation, including alkanes, alkanols, alkanals and alkanoic acids. Finally the water and solvent insoluble fraction exhibits a strong aromaticity as one would expect from black or elemental carbon like material; however, these spectra also show a substantial amount of aliphaticity consistent with linear side chains on the aromatic structures.

  15. Application of ion chromatography to the determination of water-soluble inorganic and organic ions in atmospheric aerosols

    Institute of Scientific and Technical Information of China (English)

    YU Xue-chun; HE Ke-bin; MA Yong-liang; YANG Fu-mo; DUAN Feng-kui; ZHENG Ai-hua; ZHAO Cheng-yi

    2004-01-01

    A simple, sensitive and convenient ion chromatography(IC) method was established for the simultaneous determination of twelve water-soluble inorganic ions(F-, Cl-, NO2-, NO3-, SO32-, SO42-, PO43-, Na+, NH4+, K+, Mg2+) and sixteen water-soluble organic ions(formate, acetate, MSA, oxalate, malonate, succinate, phthalates, etc.) in atmospheric aerosols. The linear concentrations ranged from 0.005 μg/m3 to 500 μg/m3(r = 0.999-0.9999). The relative standard deviation(RSD) were 0.43%-2.00% and the detection limits were from 2.7 ng/m3 to 88 ng/m3. The proposed method was successfully applied to the simultaneous determination of those inorganic ions and organic ions in PM2.5 of Beijing.

  16. Application of the NARCM model to high-resolution aerosol simulations: Case study of Mexico City basin during the Investigación sobre Materia Particulada y Deterioro Atmosférico-Aerosol and Visibility Research measurements campaign

    Science.gov (United States)

    Munoz-Alpizar, Rodrigo; Blanchet, Jean-Pierre; Quintanar, Arturo I.

    2003-08-01

    The Northern Aerosol Regional Climate Model (NARCM) is used to study the visibility and three-dimensional (3-D) evolution of aerosol distributions within the Mexico City basin. NARCM simulates transport, diffusion, deposition, and size distributions of sulphur aerosol particles in the region. The model assumes only simple sulphur oxidation, not taking explicitly into account the urban air chemistry. Rather, it focuses on detailed aerosol microphysics and 3-D optical properties. The simulation performance is compared with upper air and ground-based observations for the following specific days of intensive measurement: 2, 4, and 14 March 1997. Time series at Mexico City airport shows lower values of visibility in the morning due to a shallow mixed layer and higher values in the afternoon following the evolution of the mixed layer depth. Modeled visibility shows large dependence on cardinal direction and size distribution of particles. It is found that better resolution of particle size leads to better representation of coagulation processes and to realistic size distributions which show a characteristic accumulation mode around 0.3 μm. As a result, visibility simulations are closer to those observed at the airport location. Comparing visibility is a stringent test for the model because it requires an accurate representation of 3-D meteorological fields together with a realistic aerosol simulation.

  17. María Teresa Ronderos. Guerras recicladas. Una historia periodística del paramilitarismo en Colombia.Bogotá: Aguilar, 2014. 402 páginas.

    OpenAIRE

    Madeleine Ahumada Casas

    2015-01-01

    El 2 de octubre de 2014 se realizó en Bogotá el lanzamiento del libro Guerras Recicladas. Una historia periodística del paramilitarismo en Colombia, de la periodista María Teresa Ronderos. Este texto es descrito por sus colegas de la Silla Vacía —medio periodístico de denuncia del cual es fundadora— como “una historia periodística del paramilitarismo en el país, que busca responder cómo nació, qué influencia nacional e internacional tuvo y cómo se legitimó este fenómeno por más...

  18. Ignacio de Loyola y Teresa de Ávila. Inspectores de Espíritus : Institución y Carisma en los albores da la Era confesional

    Directory of Open Access Journals (Sweden)

    Fabián Alejandro Campagne

    2014-01-01

    Full Text Available After During the late Middle Ages, the discernment of spirits went through a revolutionary transformation: from a wonderful charism invested by the Holy Ghost, it became a human science, based upon probabilities and conjectures, and under the tight control of the theological corporation. This new discretio spirituum paradigm is known as «gersonian revolution» (because of Jean Gerson’s role in its propagation. Were the great Sixteenth Century charismatic saints enemies or supporters of this process of clericalization of religious enthusiasm? The aim of this paper is to offer some clues to the resolution of this dilemma, using as a test-case the figures of Ignatius Loyola and Teresa of Avila, two of the major references of early Counter-Reformation

  19. Servando Teresa de Mier y sus polémicas cartas a la Ilustración española

    Directory of Open Access Journals (Sweden)

    Mariana Rosetti

    2016-11-01

    Full Text Available El presente artículo analiza la particular modulación de la figura del letrado criollo que desplegó Servando Teresa de Mier en sus cartas dirigidas al historiador Juan Bautista Muñoz y al periodista sevillano José María Blanco White. Estas cartas configuraron un moderno locus de enunciación letrado que le permitió a Mier editar el saber ilustrado español tanto sobre la tradición religiosa novohispana como sobre la capacidad política de los americanos frente a la crisis institucional suscitada en el año 1808. Mier recurrió al género epistolar para configurar una red cultural trasatlántica que resignificó el discurso reivindicatorio criollista producido por el sistema colonial peninsular.

  20. 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.

  1. The application of single particle aerosol mass spectrometry for the detection and identification of high explosives and chemical warfare agents

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Audrey Noreen [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2006-01-01

    Single Particle Aerosol Mass Spectrometry (SPAMS) was evaluated as a real-time detection technique for single particles of high explosives. Dual-polarity time-of-flight mass spectra were obtained for samples of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazinane (RDX), and pentaerythritol tetranitrate (PETN); peaks indicative of each compound were identified. Composite explosives, Comp B, Semtex 1A, and Semtex 1H were also analyzed, and peaks due to the explosive components of each sample were present in each spectrum. Mass spectral variability with laser fluence is discussed. The ability of the SPAMS system to identify explosive components in a single complex explosive particle (~1 pg) without the need for consumables is demonstrated. SPAMS was also applied to the detection of Chemical Warfare Agent (CWA) simulants in the liquid and vapor phases. Liquid simulants for sarin, cyclosarin, tabun, and VX were analyzed; peaks indicative of each simulant were identified. Vapor phase CWA simulants were adsorbed onto alumina, silica, Zeolite, activated carbon, and metal powders which were directly analyzed using SPAMS. The use of metal powders as adsorbent materials was especially useful in the analysis of triethyl phosphate (TEP), a VX stimulant, which was undetectable using SPAMS in the liquid phase. The capability of SPAMS to detect high explosives and CWA simulants using one set of operational conditions is established.

  2. Application of Finite Difference Technique to Raman Lidar Signals to Derive the Altitude Profiles of Atmospheric Aerosol Extinction

    Directory of Open Access Journals (Sweden)

    PURUSOTHAM S

    2015-06-01

    Full Text Available Lidars (Laser radars are the best suitable instruments to derive the range resolved parameters of atmosphere. Single wavelength and simple backscatter lidars have been widely used to study the height profiles of particle scattering and extinction in the atmosphere. However, atmospheric extinction derived using these lidars data undergo several assumptions and hence involve a significant amount of error in estimation of extinction. The Raman lidar methodology of deriving particle extinction in the atmosphere is a simplified straight-forward method that does not involve any assumptions. The Raman lidar method of atmospheric extinction computation employs derivative of logarithm of normalized range corrected Raman backscattered signal. Usually this causes gaps in the height profiles wherever there is a gradient in the signal under examination. In the present study, a new method is proposed to derive the particle extinction in the atmospheric boundary layer. In this new method, a scheme of alternative solution methodology has been proposed using “Finite Difference Technique”. The method has an advantage that, it does not involve the gradient as compared to conventional technique and hence reduces the error. Using this method, the height profiles of particle extinction has been derived. A code in MATLAB is developed to derive the altitude distribution of aerosol extinction. In this connection, the NOAA-REDY site data has been used as the reference data for calculating the molecular extinction in the lower atmosphere.

  3. Modeling long distance dispersal of airborne foot-and-mouth disease virus as a polydisperse aerosol - Application to the emergence of a new strain from Egypt to Israel

    Science.gov (United States)

    Klausner, Ziv; Klement, Eyal; Fattal, Eyal

    2015-12-01

    Long distance dispersal (LDD) of airborne aerosol of foot-and-mouth disease (FMD) virus was extensively modeled in the literature. Most studies modeled this aerosol in simplistic approach as a passive tracer, neglecting physical and biological mechanisms that affect bio-aerosols such as the FMD aerosol. This approach was justified either because under persistent wind these mechanisms lower the extant of downwind hazard or on the grounds that the effect of some of the physical mechanisms on particles as small as the FMD particles (0.015-20 μm) is supposed to be negligible compared to the effect of atmospheric turbulence. Even when the FMD aerosol was treated as aerosol, it was assumed that it is monodisperse, i.e., all its particles are of the same size. The aim of the study is to examine whether these simplistic approaches are indeed justified when dealing with LDD of a bio-aerosol under actual atmospheric conditions. In order to do so, the influence of a more realistic modeling of the FMD aerosol as a polydisperse aerosol was compared to passive tracer and to monodisperse aerosol. The comparison refers to a case of a widespread FMD outbreak that occurred in 2012 in Egypt. This outbreak involved the emergence of a new serotype in Egypt, SAT2 and concern was raised that this serotype will advance further to Asia and Europe. Israel is located on the land bridge between Africa, Asia and Europe, and shares a long desert border with Egypt as well as a long Mediterranean shore adjacent to Egypt's shore. This unique location as well as the fact that Israel does not have any cattle trade with its neighboring countries make Israel an interesting test case for the examination of the necessary conditions for the long distance dispersal (LDD) of a new FMD strains from Africa to Europe. The analysis in this study shows that under quasi-stationary wind conditions modeling FMD dispersal as a passive tracer results in a significantly longer hazard distance. Under non

  4. Aerosol distribution apparatus

    Science.gov (United States)

    Hanson, W.D.

    An apparatus for uniformly distributing an aerosol to a plurality of filters mounted in a plenum, wherein the aerosol and air are forced through a manifold system by means of a jet pump and released into the plenum through orifices in the manifold. The apparatus allows for the simultaneous aerosol-testing of all the filters in the plenum.

  5. Papers of the 15. french congress on the aerosols CFA 99; Actes du 15. congres francais sur les aerosols CFA 99

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This french congress on the aerosols took place in Paris the 8 and 9 december 1999. It was presented in four main themes: bio-aerosols and filtering; the aerosols metrology; the aerosols in the environment; aerosols physic and applications. Seven papers have been analyzed in INIS data base for their specific interest in the nuclear industry. They concern the aerosol capture simulation, the aerosols sampling in workplace environment, a ring-effect ion generator development for the charge and the neutralization of an aerosol cloud, the radon 222 characterization in a house, a particle re-entrainment, the electrical charge process of beta emitter radioactive aerosols, the simulation of air flows in many filters. The other ones are analyzed in the ETDE data base. (A.L.B.)

  6. Papers of the 14. french congress on the 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. Eight papers have been analyzed in ETDE data base showing the importance of the aerosols physic knowledge in the air quality and seven other in the INIS data base for their specific interest in the nuclear industry. (A.L.B.)

  7. CADS:Cantera Aerosol Dynamics Simulator.

    Energy Technology Data Exchange (ETDEWEB)

    Moffat, Harry K.

    2007-07-01

    This manual describes a library for aerosol kinetics and transport, called CADS (Cantera Aerosol Dynamics Simulator), which employs a section-based approach for describing the particle size distributions. CADS is based upon Cantera, a set of C++ libraries and applications that handles gas phase species transport and reactions. The method uses a discontinuous Galerkin formulation to represent the particle distributions within each section and to solve for changes to the aerosol particle distributions due to condensation, coagulation, and nucleation processes. CADS conserves particles, elements, and total enthalpy up to numerical round-off error, in all of its formulations. Both 0-D time dependent and 1-D steady state applications (an opposing-flow flame application) have been developed with CADS, with the initial emphasis on developing fundamental mechanisms for soot formation within fires. This report also describes the 0-D application, TDcads, which models a time-dependent perfectly stirred reactor.

  8. Una propuesta de antropología teológica en castillo interior de Santa Teresa de Ávila

    Directory of Open Access Journals (Sweden)

    Agustina Serrano Pérez

    2011-01-01

    Full Text Available El artículo presenta a Santa Teresa de Ávila (1515-1582 en un contexto histórico marcado por la apertura y el resurgimiento teológico, junto con un giro a posturas rígidas. En ese tiempo ella funda 17 conventos y escribe todas sus obras. Castillo Interior es el último eslabón de su proceso de autocomunicación, en que codifica su pensamiento teológico, estructurado en siete moradas que dan cuenta de la relación entre Dios y la respuesta humana. Este trabajo muestra la antropología de una Teología mística, como la autora deine su obra Castillo Interior, y trata de sintetizar la antropología teológica teresiana como un proceso salvíico desde el origen hasta la consumación. Finalmente se ofrecen unos rasgos característicos de la antropología teresiana en la que el misterio del ser humano se esclarece en Dios trinitario, es decir en la sabiduría amorosa del Espíritu.The a presents Saint Teresa of Ávila (1515-1582 in an historical context marked by theological resurgence and opening, together with a shift to rigid positions. In this period, she founds 17 convents and writes all her work. Interior Castle is the last link in her process of self-communication, and in which she encodes her theological thinking, structured in seven mansions that account for the relationship between God and the human response. This work shows the anthropology of a Mystical theology, as the author deines her work Interior Castle, and tries to synthesize Teresian theological anthropology as a salvific process from origin to consummation. Finally, the articles gives some characteristic features of Teresian anthropology, in which the mystery of human beings is illuminated in the Trinitarian God, i.e., in the loving wisdom of the Spirit.

  9. El jesuita y confesor de Santa Teresa de Jesús, Rodrigo Álvarez: características y genealogía de su espiritualidad

    Directory of Open Access Journals (Sweden)

    González Polvillo, Antonio

    2012-06-01

    Full Text Available We will study to one of the most influential personages of the Sevillan spirituality of first half of century XVI: the Jesuit confessor of Teresa de Avila Rodrigo Alvarez. In this period a group of evangelical spirituality, paulina, visionary and prophetic organizes itself that has its origin in the axis Jerez-Lebrija and that soon will connect, through Rodrigo de Valer, with the evangelical ideas and from return to a primitive Church of the skillful canon of the cathedral of Seville Egidio, and through Rodrigo Alvarez with the Congregation of Granada, a species of school of hermetic spirituality composed by artists (Juan Bautista Vázquez, Vasco Pereira, Juan Martínez Montañés, clergymen and nuns whom its descendants in important personages in the eventful journeys of the definition of the dogma of the Immaculate Conception will have as they were Hernando de Mata and Bernardo de Toro.

    Se estudia a uno de los personajes más influyentes de la espiritualidad sevillana de la primera mitad del siglo XVI: el jesuita confesor de Teresa de Ávila Rodrigo Álvarez. En este periodo se organiza un conventículo de espiritualidad evangélica, paulina, visionaria y profética que tiene su origen en el eje Jerez-Lebrija y que pronto entroncará, a través de Rodrigo de Valer, con las ideas evangélicas y de vuelta a una Iglesia primitiva del canónigo magistral de la catedral de Sevilla Egidio, y a través de Rodrigo Álvarez con la Congregación de la Granada, una especie de escuela de espiritualidad hermética compuesta por artistas (Juan Bautista Vázquez, Vasco Pereira, Juan Martínez Montañés, clérigos seculares y monjas que tendrá su descendencia en personajes importantes en las peripecias de la definición del dogma de la Inmaculada Concepción como fueron Hernando de Mata y Bernardo de Toro.

  10. Maple在气溶胶云下清除数值模拟中的应用%Application of Maple to numerical simulation of below-cloud scavenging of aerosols

    Institute of Scientific and Technical Information of China (English)

    方志华; 刘兆荣; 白郁华; 李金龙

    2009-01-01

    云下清除是大气气溶胶粒子一个重要的清除机制,清除效果与粒径大小及雨强等气象条件密切相关,一般采用质量平均清除系数和雨强的参数化关系来定量描述.本文采用数值计算方法模拟气溶胶粒子的云下清除过程,综合考虑布朗扩散、拦截作用和惯性碰撞等机制的贡献,结合不同模态气溶胶粒子的化学成分,在Maple平台上,通过对M-P雨滴谱、雨滴终速经验公式、气溶胶粒子对数正态分布谱、雨滴对气溶胶粒子捕获系数等,基于雨滴或气溶胶粒径的多个函数进行统一符号处理和数值计算,得到CaCO3、(NH4):SO4两种典型的大气气溶胶粒子质量平均清除系数和雨强的参数化关系:CaCO3粒子为 (h-1)=0.83·P00.74,(NH4)2SO4粒子为 (h-1)=1.8×10-3·P00.64.分析r降雨过程中大气气溶胶质量浓度和雨水中Ca2+,NH4+,SO42-离子浓度的变化趋势.%Below-cloud scavenging is an important deposition mechanism for airborne aerosol particles. The scavenging coefficient de-pends on the aerosol size and meteorological conditions, Especially the precipitation rate significantly. The traditional bulk parameter-ization represents the mean wet scavenging coefficient for the whole aerosol size range. This parameterization overestimates the scaven-ging of aerosol mass and ion concentration of rainwater during a heavy or medium precipitation. In this study, the scavenging of aerosol particles in the below-cloud scavenging process was simulated, considering the contribution of collection mechanisms due to Brownian diffusion, directional interception and inertial impaction and the chemical composition of different mode aerosols. With the application of Maple software, multi functions based on either rain drop diameter or aerosol diameter were mathematically simulated and symbol processed. Those included the Marshall-Palmer raindrop size distribution, the raindrop terminal velocity, the log-normal size distribu

  11. La racionalidad apasionada. Acercamiento a la relación razón y amor en la obra "Camino de Perfección" de Santa Teresa de ávila (1515-1582

    Directory of Open Access Journals (Sweden)

    Agustina Serrano P.

    2005-01-01

    Full Text Available Santa Teresa de ávila es una de las grandes figuras de la mística del Siglo de Oro Español. Pablo VI la declara Doctora de la Iglesia el 27 de septiembre de 1970. Este hecho supone que el puesto y la función de la mujer en la Iglesia quedaron afectados cuando se declaró a Santa Teresa Doctora de la Iglesia. Camino de Perfección es la primera obra impresa de Santa Teresa, en el año 1583 quiere ser un libro guía para las comunidades. Es un itinerario de conversión recorrido con una determinada "racionalidad apasionada" que desenmascara todo lo que no está al servicio del Reino. El presente estudio pretende ayudar a detectar la racionalidad teológica de Teresa desde la relación razón y amor en su obra Camino de perfección. En él se comienza a descubrir la propia sistematicidad del pensar de esta autora. Teresa ha ido vertiendo sus ideas respecto a la realidad de todo lo humano. Lo hace de un modo experiencial y sin atenerse, demasiado, a las normas de uso de los grandes conceptos en su épocaSt. Theresa of Avila is one of the great figures of the mysticism of the Spanish "Golden Age". Paul VI declared her a Doctor of the Church on September 27th, 1970. This fact presupposes that the place and function of women in the Church were influenced when St. Theresa was declared Doctor of the Church. Road of Perfection is the first printed work of St. Theresa's, in the year 1583, and was intended to be a guide for communities. It is an itinerary of conversion traveled through with a determined "passionate rationality" that unmasks everything not at the service of the Kingdom. The present study intends to help detect the theological rationality of Theresa from the reason-love relationship in her work Road of Perfection. In it the author's own systematic thought begins to be discovered, depositing her ideas in relation to the reality of all that is human. She does this in an experiential way and without overly depending upon the norms of the

  12. Papers of the 15. french congress on the aerosols CFA 99; Actes du 15. congres francais sur les aerosols CFA 99

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This french congress on the aerosols took place in Paris the 8 and 9 december 1999. It was presented in four main themes: bio-aerosols and filtering; the aerosols metrology; the aerosols in the environment; aerosols physic and applications. Seven papers have been analyzed in INIS data base for their specific interest in nuclear industry. The four papers selected for ETDE cover a larger domain: annular slot samplers in turbulent flow, the air quality monitoring in France, suspension particles characterization in an urban area, application of the remote sensing to the atmospheric pollution. (A.L.B.)

  13. Aerosol MTF revisited

    Science.gov (United States)

    Kopeika, Norman S.; Zilberman, Arkadi; Yitzhaky, Yitzhak

    2014-05-01

    Different views of the significance of aerosol MTF have been reported. For example, one recent paper [OE, 52(4)/2013, pp. 046201] claims that the aerosol MTF "contrast reduction is approximately independent of spatial frequency, and image blur is practically negligible". On the other hand, another recent paper [JOSA A, 11/2013, pp. 2244-2252] claims that aerosols "can have a non-negligible effect on the atmospheric point spread function". We present clear experimental evidence of common significant aerosol blur and evidence that aerosol contrast reduction can be extremely significant. In the IR, it is more appropriate to refer to such phenomena as aerosol-absorption MTF. The role of imaging system instrumentation on such MTF is addressed too.

  14. María Teresa Ronderos. Guerras recicladas. Una historia periodística del paramilitarismo en Colombia.Bogotá: Aguilar, 2014. 402 páginas.

    Directory of Open Access Journals (Sweden)

    Madeleine Ahumada Casas

    2015-01-01

    Full Text Available El 2 de octubre de 2014 se realizó en Bogotá el lanzamiento del libro Guerras Recicladas. Una historia periodística del paramilitarismo en Colombia, de la periodista María Teresa Ronderos. Este texto es descrito por sus colegas de la Silla Vacía —medio periodístico de denuncia del cual es fundadora— como “una historia periodística del paramilitarismo en el país, que busca responder cómo nació, qué influencia nacional e internacional tuvo y cómo se legitimó este fenómeno por más de tres décadas”. La autora subraya que su intención es responder, desde una mirada política, a cómo y por qué pasaron las cosas y contribuir al debate sobre las guerras recicladas en Colombia

  15. Conventualización de la escritura en las Vidas de Santa Teresa de Jesús y Francisca Josefa de Castillo

    Directory of Open Access Journals (Sweden)

    Diego Fabián Arévalo Viveros

    2017-01-01

    Full Text Available El presente trabajo explora la existencia de la larga duración de las expresiones de obediencia de las monjas, paralelas y simultáneas a expresiones de subversión de lo masculino, presentes tanto en El libro de su vida de Santa Teresa de Jesús como en Su vida de Francisca Josefa de Castillo. ¿Cómo entender este complejo despliegue de estrategias de obediencia y subversión de tal manera que las veamos inseparables? Proponemos que, junto con el perfil de la monja que elabora una imagen de sí misma basada en un yo-obedezco, se manifiesta un yo-subvierto-el-orden-impuesto por el confesor. Estas dos proyecciones del yo recorren el texto y lo pueblan; le dan una fluctuación ambigua. En sus obras se produce una conventualización de la escritura, en la que escribir en el convento implica obedecerlo pero a su vez implica manifestarlo en la escritura como espacio de autonomía para descubrir el lenguaje.

  16. 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.

  17. Application of the CALIOP Layer Product to Evaluate the Vertical Distribution of Aerosols Estimated by Global Models: AeroCom Phase I Results

    Science.gov (United States)

    Koffi, Brigitte; Schulz, Michael; Breon, Francois-Marie; Griesfeller, Jan; Winker, David; Balkanski, Yves; Bauer, Susanne; Berntsen, Terje; Chin, Mian; Collins, William D.; Dentener, Frank; Diehl, Thomas; Easter, Richard; Ghan, Steven; Gimoux, Paul; Gong, Sunling; Horowitz, Larry W.; Iversen, Trond; Kirkevag, Alf; Koch, Dorothy; Krol, Maarten; Myhre, Gunnar; Stier, Philip; Takemura, Toshihiko

    2012-01-01

    The CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) layer product is used for a multimodel evaluation of the vertical distribution of aerosols. Annual and seasonal aerosol extinction profiles are analyzed over 13 sub-continental regions representative of industrial, dust, and biomass burning pollution, from CALIOP 2007-2009 observations and from AeroCom (Aerosol Comparisons between Observations and Models) 2000 simulations. An extinction mean height diagnostic (Z-alpha) is defined to quantitatively assess the models' performance. It is calculated over the 0-6 km and 0-10 km altitude ranges by weighting the altitude of each 100 m altitude layer by its aerosol extinction coefficient. The mean extinction profiles derived from CALIOP layer products provide consistent regional and seasonal specificities and a low inter-annual variability. While the outputs from most models are significantly correlated with the observed Z-alpha climatologies, some do better than others, and 2 of the 12 models perform particularly well in all seasons. Over industrial and maritime regions, most models show higher Z-alpha than observed by CALIOP, whereas over the African and Chinese dust source regions, Z-alpha is underestimated during Northern Hemisphere Spring and Summer. The positive model bias in Z-alpha is mainly due to an overestimate of the extinction above 6 km. Potential CALIOP and model limitations, and methodological factors that might contribute to the differences are discussed.

  18. MATRIX (Multiconfiguration Aerosol TRacker of mIXing state): an aerosol microphysical module for global atmospheric models

    Energy Technology Data Exchange (ETDEWEB)

    Bauer,S.E.; Wright, D.L.; Koch, D.; Lewis, E.R.; McGraw, R.; Chang, L.-S.; Schwartz, S.E.; Ruedy, R.

    2008-10-21

    A new aerosol microphysical module MATRIX, the Multiconfiguration Aerosol TRacker of mIXing state, and its application in the Goddard Institute for Space Studies (GISS) climate model (ModelE) are described. This module, which is based on the quadrature method of moments (QMOM), represents nucleation, condensation, coagulation, internal and external mixing, and cloud-drop activation and provides aerosol particle mass and number concentration and particle size information for up to 16 mixed-mode aerosol populations. Internal and external mixing among aerosol components sulfate, nitrate, ammonium, carbonaceous aerosols, dust and sea-salt particles are represented. The solubility of each aerosol population, which is explicitly calculated based on its soluble and insoluble components, enables calculation of the dependence of cloud drop activation on the microphysical characterization of multiple soluble aerosol populations. A detailed model description and results of box-model simulations of various aerosol population configurations are presented. The box model experiments demonstrate the dependence of cloud activating aerosol number concentration on the aerosol population configuration; comparisons to sectional models are quite favorable. MATRIX is incorporated into the GISS climate model and simulations are carried out primarily to assess its performance/efficiency for global-scale atmospheric model application. Simulation results were compared with aircraft and station measurements of aerosol mass and number concentration and particle size to assess the ability of the new method to yield data suitable for such comparison. The model accurately captures the observed size distributions in the Aitken and accumulation modes up to particle diameter 1 {micro}m, in which sulfate, nitrate, black and organic carbon are predominantly located; however the model underestimates coarse-mode number concentration and size, especially in the marine environment. This is more likely due

  19. MATRIX (Multiconfiguration Aerosol TRacker of mIXing state: an aerosol microphysical module for global atmospheric models

    Directory of Open Access Journals (Sweden)

    S. E. Bauer

    2008-10-01

    Full Text Available A new aerosol microphysical module MATRIX, the Multiconfiguration Aerosol TRacker of mIXing state, and its application in the Goddard Institute for Space Studies (GISS climate model (ModelE are described. This module, which is based on the quadrature method of moments (QMOM, represents nucleation, condensation, coagulation, internal and external mixing, and cloud-drop activation and provides aerosol particle mass and number concentration and particle size information for up to 16 mixed-mode aerosol populations. Internal and external mixing among aerosol components sulfate, nitrate, ammonium, carbonaceous aerosols, dust and sea-salt particles are represented. The solubility of each aerosol population, which is explicitly calculated based on its soluble and insoluble components, enables calculation of the dependence of cloud drop activation on the microphysical characterization of multiple soluble aerosol populations.

    A detailed model description and results of box-model simulations of various aerosol population configurations are presented. The box model experiments demonstrate the dependence of cloud activating aerosol number concentration on the aerosol population configuration; comparisons to sectional models are quite favorable. MATRIX is incorporated into the GISS climate model and simulations are carried out primarily to assess its performance/efficiency for global-scale atmospheric model application. Simulation results were compared with aircraft and station measurements of aerosol mass and number concentration and particle size to assess the ability of the new method to yield data suitable for such comparison. The model accurately captures the observed size distributions in the Aitken and accumulation modes up to particle diameter 1 μm, in which sulfate, nitrate, black and organic carbon are predominantly located; however the model underestimates coarse-mode number concentration and size, especially in the marine environment

  20. 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

  1. Separating Dust Mixtures and Other External Aerosol Mixtures Using Airborne High Spectral Resolution Lidar Data

    Science.gov (United States)

    Burton, S. P.; Ferrare, R. A.; Vaughan, M.; Hostetler, C. A.; Rogers, R. R.; Hair, J. W.; Cook, A. L.; Harper, D. B.

    2013-12-01

    Knowledge of aerosol type is important for source attribution and for determining the magnitude and assessing the consequences of aerosol radiative forcing. The NASA Langley Research Center airborne High Spectral Resolution Lidar (HSRL-1) has acquired considerable datasets of both aerosol extensive parameters (e.g. aerosol optical depth) and intensive parameters (e.g. aerosol depolarization ratio, lidar ratio) that can be used to infer aerosol type. An aerosol classification methodology has been used extensively to classify HSRL-1 aerosol measurements of different aerosol types including dust, smoke, urban pollution, and marine aerosol. However, atmospheric aerosol is frequently not a single pure type, but instead occurs as a mixture of types, and this mixing affects the optical and radiative properties of the aerosol. Here we present a comprehensive and unified set of rules for characterizing external mixtures using several key aerosol intensive parameters: extinction-to-backscatter ratio (i.e. lidar ratio), backscatter color ratio, and depolarization ratio. Our mixing rules apply not just to the scalar values of aerosol intensive parameters, but to multi-dimensional normal distributions with variance in each measurement dimension. We illustrate the applicability of the mixing rules using examples of HSRL-1 data where mixing occurred between different aerosol types, including advected Saharan dust mixed with the marine boundary layer in the Caribbean Sea and locally generated dust mixed with urban pollution in the Mexico City surroundings. For each of these cases we infer a time-height cross section of mixing ratio along the flight track and we partition aerosol extinction into portions attributed to the two pure types. Since multiple aerosol intensive parameters are measured and included in these calculations, the techniques can also be used for cases without significant depolarization (unlike similar work by earlier researchers), and so a third example of a

  2. DARE : Dedicated Aerosols Retrieval Experiment

    NARCIS (Netherlands)

    Smorenburg, K.; Courrèges-Lacoste, G.B.; Decae, R.; Court, A.J.; Leeuw, G. de; Visser, H.

    2004-01-01

    At present there is an increasing interest in remote sensing of aerosols from space because of the large impact of aerosols on climate, earth observation and health. TNO has performed a study aimed at improving aerosol characterisation using a space based instrument and state-of-the-art aerosol retr

  3. Spatial Correlations of Aerosol Optical Depth Over Land

    Science.gov (United States)

    Radkevich, A. V.; Trishchenko, A. P.

    2009-05-01

    The accurate atmospheric correction of historical satellite long-term data is required to make them suitable for climate change application. This is essential to properly identify the impacts caused by changing surface properties, such as vegetation, soil and snow cover, rather than atmospheric effects, cloud contamination and artefacts. The correction of satellite data over land for aerosol effect constitutes the most challenging part of the processing. While a good progress in aerosol retrievals has been achieved in recent years using the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Multi-angle Imaging Spectroradiometer (MISR), the aerosol properties and their associated impact on atmospheric correction for historical data over land from the Advanced Very High Resolution Radiometer (AVHRR) onboard NOAA satellites for pre-MODIS period is still not adequately addressed. It seems promising to develop the AVHRR atmospheric correction algorithm based on the synthesis of aerosol retrievals over dark targets and optimum interpolation technique based on aerosol spatio-temporal statistics. The implementation of this approach requires the knowledge of aerosol spatial correlation function. The estimates of aerosol optical depth (AOD) spatial correlation function were obtained in this study using different data sources: MODIS level 2 and level 3 aerosol products, daily averages of ground sun photometer aerosol retrievals from Aerosol Robotic Network (AERONET) and the global chemistry and aerosol atmospheric transport model results from NASA's GOCART. The AOD correlation properties obtained from different types of MODIS aerosol products were found in reasonably good agreement with each other. The AOD correlation radius for different types of MODIS data varied from 418 km to 900 km. The AOD correlation radius obtained from AERONET data was found to be close to 500km. Substantial differences were detected between AOD spatial correlation function derived from

  4. Una biografía novelada de María Teresa León: «Cervantes, el soldado que nos enseñó a hablar»

    Directory of Open Access Journals (Sweden)

    Carla Perugini

    2013-11-01

    Full Text Available En la biografía novelada se juntan, aparentemente contradictorios, el aspecto documental y científico de la historia con el subjetivismo y lo imaginativo de la ficción.Las cinco biografías noveladas de María Teresa León son, en el orden: El gran amor de Gustavo Adolfo Bécquer (Buenos Aires 1946; Rodrigo Díaz de Vivar el Cid Campeador (Buenos Aires 1954; Doña Jimena Díaz del Vivar. Gran señora de todos los deberes (Buenos Aires 1960; Menesteos, marinero de abril (México 1965; Cervantes, el soldado que nos enseñó a hablar (Madrid 1978. Llaman la atención inmediatamente dos elementos comunes: el haber sido escritas todas en el exilio, incluso la de Cervantes, última obra de la autora todavía exiliada en Roma, y su dedicación a figuras marcadas por un destino malhadado y heróico, y, cada una a su manera, ejemplares.La atención hacia los clásicos, y hacia Cervantes en particular, fue una constante en la generación de intelectuales que salieron de España después de la derrota. En la biografía de María Teresa se nota una fuerte compenetración entre escritores, la moderna y el antiguo, que llegará hasta la invención de detalles existenciales del biografiado, al que la autora ofrece su voz, su manera de pensar, sus ideales.Palabras clave: María Teresa León, biografía novelada, Cervantes

  5. Aqueous-phase mechanism for secondary organic aerosol formation from isoprene: application to the Southeast United States and co-benefit of SO2 emission controls

    Directory of Open Access Journals (Sweden)

    E. A. Marais

    2015-11-01

    Full Text Available Isoprene emitted by vegetation is an important precursor of secondary organic aerosol (SOA, but the mechanism and yields are uncertain. Aerosol is prevailingly aqueous under the humid conditions typical of isoprene-emitting regions. Here we develop an aqueous-phase mechanism for isoprene SOA formation coupled to a detailed gas-phase isoprene oxidation scheme. The mechanism is based on aerosol reactive uptake probabilities (γ for water-soluble isoprene oxidation products, including sensitivity to aerosol acidity and nucleophile concentrations. We apply this mechanism to simulation of aircraft (SEAC4RS and ground-based (SOAS observations over the Southeast US in summer 2013 using the GEOS-Chem chemical transport model. Emissions of nitrogen oxides (NOx ≡ NO + NO2 over the Southeast US are such that the peroxy radicals produced from isoprene oxidation (ISOPO2 react significantly with both NO (high-NOx pathway and HO2 (low-NOx pathway, leading to different suites of isoprene SOA precursors. We find a mean SOA mass yield of 3.3 % from isoprene oxidation, consistent with the observed relationship of OA and formaldehyde (a product of isoprene oxidation. The yield is mainly contributed by two immediate gas-phase precursors, isoprene epoxydiols (IEPOX, 58 % of isoprene SOA from the low-NOx pathway and glyoxal (28 % from both low- and high-NOx pathways. This speciation is consistent with observations of IEPOX SOA from SOAS and SEAC4RS. Observations show a strong relationship between IEPOX SOA and sulfate aerosol that we explain as due to the indirect effect of sulfate on aerosol acidity and volume, rather than a direct mechanistic role for sulfate. Isoprene SOA concentrations increase as NOx emissions decrease (favoring the low-NOx pathway for isoprene oxidation, but decrease as SO2 emissions decrease (due to the effect of sulfate on aerosol acidity and volume. The US EPA projects 2013–2025 decreases in anthropogenic emissions of 34 % for NOx

  6. Aqueous-phase mechanism for secondary organic aerosol formation from isoprene: application to the Southeast United States and co-benefit of SO2 emission controls

    Science.gov (United States)

    Marais, E. A.; Jacob, D. J.; Jimenez, J. L.; Campuzano-Jost, P.; Day, D. A.; Hu, W.; Krechmer, J.; Zhu, L.; Kim, P. S.; Miller, C. C.; Fisher, J. A.; Travis, K.; Yu, K.; Hanisco, T. F.; Wolfe, G. M.; Arkinson, H. L.; Pye, H. O. T.; Froyd, K. D.; Liao, J.; McNeill, V. F.

    2015-11-01

    Isoprene emitted by vegetation is an important precursor of secondary organic aerosol (SOA), but the mechanism and yields are uncertain. Aerosol is prevailingly aqueous under the humid conditions typical of isoprene-emitting regions. Here we develop an aqueous-phase mechanism for isoprene SOA formation coupled to a detailed gas-phase isoprene oxidation scheme. The mechanism is based on aerosol reactive uptake probabilities (γ) for water-soluble isoprene oxidation products, including sensitivity to aerosol acidity and nucleophile concentrations. We apply this mechanism to simulation of aircraft (SEAC4RS) and ground-based (SOAS) observations over the Southeast US in summer 2013 using the GEOS-Chem chemical transport model. Emissions of nitrogen oxides (NOx ≡ NO + NO2) over the Southeast US are such that the peroxy radicals produced from isoprene oxidation (ISOPO2) react significantly with both NO (high-NOx pathway) and HO2 (low-NOx pathway), leading to different suites of isoprene SOA precursors. We find a mean SOA mass yield of 3.3 % from isoprene oxidation, consistent with the observed relationship of OA and formaldehyde (a product of isoprene oxidation). The yield is mainly contributed by two immediate gas-phase precursors, isoprene epoxydiols (IEPOX, 58 % of isoprene SOA) from the low-NOx pathway and glyoxal (28 %) from both low- and high-NOx pathways. This speciation is consistent with observations of IEPOX SOA from SOAS and SEAC4RS. Observations show a strong relationship between IEPOX SOA and sulfate aerosol that we explain as due to the indirect effect of sulfate on aerosol acidity and volume, rather than a direct mechanistic role for sulfate. Isoprene SOA concentrations increase as NOx emissions decrease (favoring the low-NOx pathway for isoprene oxidation), but decrease as SO2 emissions decrease (due to the effect of sulfate on aerosol acidity and volume). The US EPA projects 2013-2025 decreases in anthropogenic emissions of 34 % for NOx (leading to 7

  7. Vertical variations of aerosols and the effects responded to the emission control: application of lidar ceilometer in Beijing during APEC, 2014

    Directory of Open Access Journals (Sweden)

    G. Tang

    2015-05-01

    Full Text Available During the 2014 Asia-Pacific Economic Cooperation (APEC summit, a reduction of air pollution sources was coordinated to ensure good air quality in Beijing and the surrounding provinces and cities. By investigating variations in air pollution during this period, the effects of local emissions and regional transport can be better understood and the information can be used to evaluate the effectiveness of emission reduction strategies and provide a theoretical basis to guide future emission reduction strategies. From 15 October to 30 November 2014, the height of the atmospheric mixing layer and the aerosol attenuated backscattering coefficient profile were observed online using a lidar ceilometer. By investigating the correlation between fine particulate matter (PM2.5 data near the surface and attenuated backscattering coefficients measured by the lidar ceilometer as well as the correlation between aerosol optical depth (AOD and attenuated backscattering coefficients of the 0 to 4500 m column, we found that the attenuated backscattering coefficient measured by the lidar ceilometer is highly correlated with the PM2.5 concentration and AOD (correlation coefficients of 0.89 and 0.86, respectively. This result demonstrates the reliability of the vertical profile of aerosols measured by the lidar ceilometer. By analyzing the atmospheric backscattering profile, we found that during the initial stage of pollution accumulation, which is affected by transport of southerly jet flows at low altitude, the attenuated backscattering coefficient of atmospheric aerosols from 0 to 1500 m was greatly enhanced by approximately 1.4 Mm-1 sr-1 (140%. At the peak pollution stage, the height of the mixing layer gradually decreased, the ratio of CO/SO2 gradually increased and emissions were dominated by local emissions. The attenuated backscattering coefficient of aerosols from 0 to 300 m suddenly increased, and the aerosols near surface had the highest value

  8. MSA in Beijing aerosol

    Institute of Scientific and Technical Information of China (English)

    YUAN Hui; WANG Ying; ZHUANG Guoshun

    2004-01-01

    Methane sulphonate (MSA) and sulfate (SO42-), the main oxidation products of dimethyl sulfide (DMS), are the target of atmospheric chemistry study, as sulfate aerosol would have important impact on the global climate change. It is widely believed that DMS is mainly emitted from phytoplankton production in marine boundary layer (MBL), and MSA is usually used as the tracer of non-sea-salt sulfate (nss- SO42-) in marine and coastal areas (MSA/SO42- = 1/18). Many observations of MSA were in marine and coastal aerosols. To our surprise, MSA was frequently (>60%) detected in Beijing TSP, PM10, and PM2.5 aerosols, even in the samples collected during the dust storm period. The concentrations of MSA were higher than those measured in marine aerosols. Factor analysis, correlation analysis and meteorology analysis indicated that there was no obvious marine influence on Beijing aerosols. DMS from terrestrial emissions and dimethyl sulphoxide (DMSO) from industrial wastes could be the two possible precursors of MSA. Warm and low-pressure air masses and long time radiation were beneficial to the formation of MSA. Anthropogenic pollution from regional and local sources might be the dominant contributor to MSA in Beijing aerosol. This was the first report of MSA in aerosols collected in an inland site in China. This new finding would lead to the further study on the balance of sulfur in inland cities and its global biogeochemical cycle.

  9. MATRIX (Multiconfiguration Aerosol TRacker of mIXing state: an aerosol microphysical module for global atmospheric models

    Directory of Open Access Journals (Sweden)

    S. E. Bauer

    2008-05-01

    Full Text Available A new aerosol microphysical module MATRIX, the Multiconfiguation Aerosol TRacker of mIXing state, and its application in the Goddard Institute for Space Studies (GISS climate model (ModelE is described. This module, which is based on the quadrature method of moments (QMOM, represents nucleation, condensation, coagulation, internal and external mixing, and cloud-drop activation and provides aerosol particle mass and number concentration and particle size information for up to 16 mixed-mode aerosol populations. Internal and external mixing among aerosol components sulfate, nitrate, ammonium, carbonaceous aerosols, dust and sea-salt particles are represented. The solubility of each aerosol mode, which is explicitly calculated based on its soluble and insoluble components, enables calculation of the dependence of cloud drop activation on the microphysical characterization of multiple soluble modes. A detailed model description and results of box-model simulations of various mode configurations are presented. The number concentration of aerosol particles activated to cloud drops depends on the mode configuration. Simulations on the global scale with the GISS climate model are evaluated against aircraft and station measurements of aerosol mass and number concentration and particle size. The model accurately captures the observed size distributions in the aitken and accumulation modes up to particle diameter 1 μm, in which sulfate, nitrate, black and organic carbon are predominantly located; however the model underestimates coarse-mode number concentration and size, especially in the marine environment.

  10. Glyoxal and methylglyoxal in Atlantic seawater and marine aerosol particles: method development and first application during the Polarstern cruise ANT XXVII/4

    Science.gov (United States)

    van Pinxteren, M.; Herrmann, H.

    2013-12-01

    An analytical method for the determination of the alpha dicarbonyls glyoxal (GLY) and methylglyoxal (MGLY) from seawater and marine aerosol particles is presented. The method is based on derivatization with o-(2,3,4,5,6-Pentafluorobenzyl)-hydroxylamine (PFBHA) reagent, solvent extraction and GC-MS (SIM) analysis. The method showed good precision (RSD Capetown to Bremerhaven in spring 2011. GLY and MGLY were determined in the sea surface microlayer (SML) of the ocean and corresponding bulk water (BW) with average concentrations of 228 ng L-1 (GLY) and 196 ng L-1 (MGLY). The results show a significant enrichment (factor of 4) of GLY and MGLY in the SML. Furthermore, marine aerosol particles (PM1) were sampled during the cruise and analyzed for GLY (average concentration 0.19 ng m-3) and MGLY (average concentration 0.15 ng m-3). On aerosol particles, both carbonyls show a very good correlation with oxalate, supporting the idea of a secondary formation of oxalic acid via GLY and MGLY. Concentrations of GLY and MGLY in seawater and on aerosol particles were correlated to environmental parameters such as global radiation, temperature, distance to the coastline and biological activity. There are slight hints for a photochemical production of GLY and MGLY in the SML (significant enrichment in the SML, higher enrichment at higher temperature). However, a clear connection of GLY and MGLY to global radiation as well as to biological activity cannot be concluded from the data. A slight correlation between GLY and MGLY in the SML and in aerosol particles could be a hint for interactions, in particular of GLY, between seawater and the atmosphere.

  11. Coagulation effect on the activity size distributions of long lived radon progeny aerosols and its application to atmospheric residence time estimation techniques.

    Science.gov (United States)

    Anand, S; Mayya, Y S

    2015-03-01

    The long lived naturally occurring radon progeny species in the atmosphere, namely (210)Pb, (210)Bi and (210)Po, have been used as important tracers for understanding the atmospheric mixing processes and estimating aerosol residence times. Several observations in the past have shown that the activity size distribution of these species peaks at larger particle sizes as compared to the short lived radon progeny species - an effect that has been attributed to the process of coagulation of the background aerosols to which they are attached. To address this issue, a mathematical equation is derived for the activity-size distribution of tracer species by formulating a generalized distribution function for the number of tracer atoms present in coagulating background particles in the presence of radioactive decay and removal. A set of these equations is numerically solved for the progeny chain using Fuchs coagulation kernel combined with a realistic steady-state aerosol size spectrum that includes nucleation, accumulation and coarse mode components. The important findings are: (i) larger shifts in the modal sizes of (210)Pb and (210)Po at higher aerosol concentrations such as that found in certain Asian urban regions (ii) enrichment of tracer specific activity on particles as compared to that predicted by pure attachment laws (iii) sharp decline of daughter-to-parent activity ratios for decreasing particle sizes. The implication of the results to size-fractionated residence time estimation techniques is highlighted. A coagulation corrected graphical approach is presented for estimating the residence times from the size-segregated activity ratios of (210)Bi and (210)Po with respect to (210)Pb. The discrepancy between the residence times predicted by conventional formula and the coagulation corrected approach for specified activity ratios increases at higher atmospheric aerosol number concentrations (>10(10) #/m(3)) for smaller sizes (<1 μm). The results are further

  12. Glyoxal and methylglyoxal in Atlantic seawater and marine aerosol particles: method development and first application during the Polarstern cruise ANT XXVII/4

    Directory of Open Access Journals (Sweden)

    M. van Pinxteren

    2013-06-01

    Full Text Available An analytical method for the determination of the alpha dicarbonyls glyoxal (GLY and methylglyoxal (MGLY from seawater and marine aerosol samples is presented. The method is based on derivatisation with o-(2,3,4,5,6-Pentafluorobenzyl-hydroxylamine (PFBHA reagent, solvent extraction and GC-MS (SIM analysis. The method showed good precision (RSD −1 range, and accuracy (good agreement between external calibration and standard addition. The method was applied to determine GLY and MGLY in oceanic water sampled during the POLARSTERN cruise ANT XXVII/4 from Capetown to Bremerhaven in spring 2011. GLY and MGLY were determined in the sea surface microlayer (SML of the ocean and corresponding bulkwater (BW with average concentrations of 228 ng L−1 (GLY and 196 ng L−1 (MGLY. The results show a significant enrichment (factor of 4 of GLY and MGLY in the SML. Furthermore, marine aerosol particles (PM1 were sampled during the cruise and analyzed for GLY (average concentration 0.19 ng m−3 and MGLY (average concentration 0.15 ng m−3. On aerosol particles, both carbonyls show a very good correlation with oxalate, supporting the idea of a secondary formation of oxalic acid via GLY and MGLY. Concentrations of GLY and MGLY in seawater and on aerosol particles were correlated to environmental parameters such as global radiation, temperature, distance to the coastline and biological activity. There are slight hints for a photochemical production of GLY and MGLY in the SML (significant enrichment in the SML, higher enrichment at higher temperature. However, a clear connection of GLY and MGLY to global radiation as well as to biological activity cannot be concluded from the data. A slight correlation between GLY and MGLY in the SML and in aerosols could be a hint for interactions of especially GLY between seawater and the atmosphere.

  13. Chama da fé, luz da razão : o ideário de frei Servando Teresa de Mier no contexto das independências hispano-americanas

    OpenAIRE

    Rocha, Carolina da Cunha

    2011-01-01

    Esta dissertação visa a compreensão da realocação de ideários europeus e norte-americanos para o contexto hispano-americano de formação dos estados nacionais independentes, na passagem do século XVIII para o início do século XIX, momento em que as correntes de pensamento do Iluminismo fluíam para o universo colonial, tomando-se por base os trabalhos do frei dominicano mexicano Servando Teresa de Mier (1763-1827). Por ter sido testemunha privilegiada, ao percorrer lugares de onde emanavam as o...

  14. OLIVAR, Revista de Literatura y Cultura Españolas, Memoria de la Guerra Civil española, Raquel Macciuci y María Teresa Pochat (eds.

    Directory of Open Access Journals (Sweden)

    Rose Duroux

    2010-07-01

    Full Text Available Las editoras, Raquel Macciuci (Universidad Nacional de La Plata y María Teresa Pochat (Universidad de Buenos Aires, dicen en el texto de introducción que al dedicar a la Guerra Civil española el octavo número de Olivar, a los setenta años de su comienzo, aceptaron un «reto dificultoso» pues la carga conmemorativa aumentaba las prevenciones contra los lugares comunes. Tenían claro que la experiencia traumática debe ser un legado activo no una retórica conmemorativa destinada a desaparecer co...

  15. “Mujeres en el Brasil Colonial: El caso del Recogimiento de la Santa Casa de la Misericórdia de Bahia a través de la Depositada Teresa de Jesus”

    OpenAIRE

    Beites Manso, Maria de Deus

    2007-01-01

    Dado el elevado número de fuentes posibles, hemos seleccionado para este trabajo el núcleo documental relacionado con D. Teresa de Jesús María que, en el seguimiento del proceso de divorcio (1751) fue “encarcelada” en el recogimiento de la Santa Casa de la Misericordia, contra su voluntad. Durante años, aunque encarcelada, mantuvo un contencioso contra su marido y los poderes locales que la quisieron castigar y alejar de la sociedad en la que siempre había vivido. La documen...

  16. Evaluation of liquid aerosol transport through porous media

    Science.gov (United States)

    Hall, R.; Murdoch, L.; Falta, R.; Looney, B.; Riha, B.

    2016-07-01

    Application of remediation methods in contaminated vadose zones has been hindered by an inability to effectively distribute liquid- or solid-phase amendments. Injection as aerosols in a carrier gas could be a viable method for achieving useful distributions of amendments in unsaturated materials. The objectives of this work were to characterize radial transport of aerosols in unsaturated porous media, and to develop capabilities for predicting results of aerosol injection scenarios at the field-scale. Transport processes were investigated by conducting lab-scale injection experiments with radial flow geometry, and predictive capabilities were obtained by developing and validating a numerical model for simulating coupled aerosol transport, deposition, and multi-phase flow in porous media. Soybean oil was transported more than 2 m through sand by injecting it as micron-scale aerosol droplets. Oil saturation in the sand increased with time to a maximum of 0.25, and decreased with radial distance in the experiments. The numerical analysis predicted the distribution of oil saturation with only minor calibration. The results indicated that evolution of oil saturation was controlled by aerosol deposition and subsequent flow of the liquid oil, and simulation requires including these two coupled processes. The calibrated model was used to evaluate field applications. The results suggest that amendments can be delivered to the vadose zone as aerosols, and that gas injection rate and aerosol particle size will be important controls on the process.

  17. Toward a Combined SAGE II-HALOE Aerosol Climatology: An Evaluation of HALOE Version 19 Stratospheric Aerosol Extinction Coefficient Observations

    Science.gov (United States)

    Thomason, L. W.

    2012-01-01

    Herein, the Halogen Occultation Experiment (HALOE) aerosol extinction coefficient data is evaluated in the low aerosol loading period after 1996 as the first necessary step in a process that will eventually allow the production of a combined HALOE/SAGE II (Stratospheric Aerosol and Gas Experiment) aerosol climatology of derived aerosol products including surface area density. Based on these analyses, it is demonstrated that HALOE's 3.46 microns is of good quality above 19 km and suitable for scientific applications above that altitude. However, it is increasingly suspect at lower altitudes and should not be used below 17 km under any circumstances after 1996. The 3.40 microns is biased by about 10% throughout the lower stratosphere due to the failure to clear NO2 but otherwise appears to be a high quality product down to 15 km. The 2.45 and 5.26 micron aerosol extinction coefficient measurements are clearly biased and should not be used for scientific applications after the most intense parts of the Pinatubo period. Many of the issues in the aerosol data appear to be related to either the failure to clear some interfering gas species or doing so poorly. For instance, it is clear that the 3.40micronaerosol extinction coefficient measurements can be improved through the inclusion of an NO2 correction and could, in fact, end up as the highest quality overall HALOE aerosol extinction coefficient measurement. It also appears that the 2.45 and 5.26 micron channels may be improved by updating the Upper Atmosphere Pilot Database which is used as a resource for the removal of gas species otherwise not available from direct HALOE measurements. Finally, a simple model to demonstrate the promise of mixed visible/infrared aerosol extinction coefficient ensembles for the retrieval of bulk aerosol properties demonstrates that a combined HALOE/SAGE II aerosol climatology is feasible and may represent a substantial improvement over independently derived data sets.

  18. Teatro infantil, gênero e direitos humanos: um olhar crítico sobre as peças Felizardo e O menino Teresa Child theatre, gender and Human Rights: an analysis of the plays Felizardo and O menino Teresa

    Directory of Open Access Journals (Sweden)

    Jorge Knijnik

    2011-12-01

    Full Text Available A cultura infantil está cada vez mais permeada por um cotidiano generificado, isto é, a maior parte dos processos e produtos culturais possui conteúdos nos quais a questão de gênero é tratada, insistentemente, de forma binária e, consequentemente, excludente. O objetivo deste trabalho, assim, foi estudar o teatro infantil de Marcelo Romagnoli e da Banda Mirim, cujas peças possuem uma proposta de desmontar e questionar os estereótipos que dicotomizam a vida de meninos e meninas. Assistindo às encenações de Felizardo e de O menino Teresa, e analisando o conteúdo dos textos das peças, concluiu-se que as personagens propõem um modelo para meninas e meninos que está na contramão da cultura padronizada e oficial, estimulando novas relações sociais de gênero entre as crianças, contribuindo desse modo para a consecução dos "objetivos do milênio" propostos pela ONU e encampados pelo Brasil, sobretudo no que tange à igualdade entre os sexos.Child culture is increasingly more permeated by a gendered quotidian, i.e., most of the cultural processes and products portray content where the gender issue is insistently treated in a binary form and, consequently, excluding. The purpose of this paper, therefore, was to study Marcelo Romagnoli's children's theater and the Children's Band (Banda Mirim, whose plays are designed to take apart and question the stereotypes that dichotomize boys´ and girls´ lives. Watching the staging of Felizardo and O menino Teresa and analyzing the context of the texts, it was found that the characters propose a model for boys and girls that goes against the standard and official culture, encouraging new gender social relations among children, contributing, therefore, to the achievement of the "goals of the millennium" as proposed by the UN and adopted by Brazil, especially as equality between the sexes is regarded.

  19. 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.

  20. 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.

  1. RACORO aerosol data processing

    Energy Technology Data Exchange (ETDEWEB)

    Elisabeth Andrews

    2011-10-31

    The RACORO aerosol data (cloud condensation nuclei (CCN), condensation nuclei (CN) and aerosol size distributions) need further processing to be useful for model evaluation (e.g., GCM droplet nucleation parameterizations) and other investigations. These tasks include: (1) Identification and flagging of 'splash' contaminated Twin Otter aerosol data. (2) Calculation of actual supersaturation (SS) values in the two CCN columns flown on the Twin Otter. (3) Interpolation of CCN spectra from SGP and Twin Otter to 0.2% SS. (4) Process data for spatial variability studies. (5) Provide calculated light scattering from measured aerosol size distributions. Below we first briefly describe the measurements and then describe the results of several data processing tasks that which have been completed, paving the way for the scientific analyses for which the campaign was designed. The end result of this research will be several aerosol data sets which can be used to achieve some of the goals of the RACORO mission including the enhanced understanding of cloud-aerosol interactions and improved cloud simulations in climate models.

  2. LES of Laminar-to-Turbulent Particle-Fluid Dynamics in Human and Nonhuman Primate Airways: Applications to Aerosolized Drug Delivery Animal Testing

    Science.gov (United States)

    Geisler, Taylor; Padhy, Sourav; Shaqfeh, Eric; Iaccarino, Gianluca

    2016-11-01

    Both the human health benefit and risk from the inhalation of aerosolized medications is often predicted by extrapolating experimental data taken using nonhuman primates to human inhalation. In this study, we employ Large Eddy Simulation to simulate particle-fluid dynamics in realistic upper airway models of both humans and rhesus monkeys. We report laminar-to-turbulent flow transitions triggered by constrictions in the upper trachea and the persistence of unsteadiness into the low Reynolds number bifurcating lower airway. Micro-particle deposition fraction and locations are shown to depend significantly on particle size. In particular, particle filtration in the nasal airways is shown to approach unity for large aerosols (8 microns) or high-rate breathing. We validate the accuracy of LES mean flow predictions using MRV imaging results. Additionally, particle deposition fractions are validated against experiments in 3 model airways.

  3. Patient's Guide to Aerosol Drug Delivery

    Science.gov (United States)

    ... Table of Contents Page Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 ................................................................ 1. Aerosol Drug Delivery: The Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Aerosol Drugs: The Major Categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12 3. Aerosol Drug Delivery Devices: Small-Volume Nebulizers . . . . . . . . . . . . .17 4. Aerosol Drug ...

  4. Classification of Aerosol Retrievals from Spaceborne Polarimetry Using a Multiparameter Algorithm

    Science.gov (United States)

    Russell, Philip B.; Kacenelenbogen, Meloe; Livingston, John M.; Hasekamp, Otto P.; Burton, Sharon P.; Schuster, Gregory L.; Johnson, Matthew S.; Knobelspiesse, Kirk D.; Redemann, Jens; Ramachandran, S.; Holben, Brent

    2013-01-01

    In this presentation, we demonstrate application of a new aerosol classification algorithm to retrievals from the POLDER-3 polarimter on the PARASOL spacecraft. Motivation and method: Since the development of global aerosol measurements by satellites and AERONET, classification of observed aerosols into several types (e.g., urban-industrial, biomass burning, mineral dust, maritime, and various subtypes or mixtures of these) has proven useful to: understanding aerosol sources, transformations, effects, and feedback mechanisms; improving accuracy of satellite retrievals and quantifying assessments of aerosol radiative impacts on climate.

  5. Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Timothy Onasch

    2009-09-09

    due to coatings on soot particles). The successfully completed Phase I project included construction of a prototype design for the TD with detailed physical modeling, testing with laboratory and ambient aerosol particles, and the initiation of a detailed microphysical model of the aerosol particles passing through the TD to extract vapor pressure distributions. The objective of the microphysical model is to derive vapor pressure distributions (i.e. vapor pressure ranges, including single chemical compounds, mixtures of known compounds, and complex ‘real-world’ aerosols, such as SOA, and soot particles with absorbing and nonabsorbing coatings) from TD measurements of changes in particle size, mass, and chemical composition for known TD temperatures and flow rates (i.e. residence times). The proposed Phase II project was designed to optimize several TD systems for different instrument applications and to combine the hardware and modeling into a robust package for commercial sales.

  6. 聚乙二醇沉淀法在流感病毒气溶胶检测中的应用%Application of PEG precipitation method in detection of influenza virus aerosol

    Institute of Scientific and Technical Information of China (English)

    刘凡; 张宝莹; 叶丹; 葛覃兮; 刘航

    2013-01-01

    目的 初步探讨聚乙二醇(PEG)沉淀法对流感病毒气溶胶的浓缩效果.方法 于2012年12月-2013年1月随机选取南京市5家商场超市和3家综合医院,采集室内可能含流感病毒的气溶胶样品,气溶胶经过不同的吸收液浓缩量、PEG-6000和NaCI加入量进行浓缩后提取RNA,以一步法逆转录巢式PCR检测甲型流感病毒.结果 当PEG-6000和NaCI终浓度为7%和2.9%(m/V)浓缩10、20 ml吸收液以及PEG-6000和NaC1终浓度为14%和5.8%(m/V)浓缩10ml吸收液时,甲型流感病毒的阳性检出率分别为17.5%,60%,30%,差异有统计学意义(P=0.008).结论 PEG沉淀法可应用于流感病毒气溶胶的浓缩,并利于流感病毒的检出.%Objective To explore concentrate effect of PEG-6000 precipitation for influenza virus aerosol.Methods The influenza virus aerosol was collected from five supermarkets and three general hospitals of Jiangsu in Dec.,2012 and Jan.,2013.The collection medium of influenza virus aerosol was concentrated by PEG-6000-NaCl precipitation and then influenza virus A was detected by Nested-PCR.Results The positive rates of influenza A virus were 17.5%,60% and 30% when the final concentration of PEG-6000/NaCl were 7%/2.9%(m/V) for 10ml and 20ml collection medium,14%/5.8%(m/V) for 10ml collection medium.There was significant difference in the positive rate of influenza virus in three concentrate conditions (P=0.008).Conclusion The PEG-6000 precipitation is applicable to the concentration of influenza virus aerosol.

  7. Generation of aerosolized drugs.

    Science.gov (United States)

    Wolff, R K; Niven, R W

    1994-01-01

    The expanding use of inhalation therapy has placed demands on current aerosol generation systems that are difficult to meet with current inhalers. The desire to deliver novel drug entities such as proteins and peptides, as well as complex formulations including liposomes and microspheres, requires delivery systems of improved efficiency that will target the lung in a reproducible manner. These efforts have also been spurred by the phase out of chlorofluorocarbons (CFCs) and this has included a directed search for alternative propellants. Consequently, a variety of new aerosol devices and methods of generating aerosols are being studied. This includes the use of freon replacement propellants, dry powder generation systems, aqueous unit spray systems and microprocessor controlled technologies. Each approach has advantages and disadvantages depending upon each principle of action and set of design variables. In addition, specific drugs may be better suited for one type of inhaler device vs. another. The extent to which aerosol generation systems achieve their goals is discussed together with a summary of selected papers presented at the recent International Congress of Aerosols in Medicine.

  8. Comparison of aerosol and bioaerosol collection on air filters

    OpenAIRE

    Miaskiewicz-Peska, Ewa; Lebkowska, Maria

    2011-01-01

    Air filters efficiency is usually determined by non-biological test aerosols, such as potassium chloride particles, Arizona dust or di-ethyl-hexyl-sebacate (DEHS) oily liquid. This research was undertaken to asses, if application of non-biological aerosols reflects air filters capacity to collect particles of biological origin. The collection efficiency for non-biological aerosol was tested with the PALAS set and ISO Fine Test Dust. Flow rate during the filtration process was 720 l/h, and par...

  9. Chemical aerosol Raman detector

    Science.gov (United States)

    Aggarwal, R. L.; Farrar, L. W.; Di Cecca, S.; Amin, M.; Perkins, B. G.; Clark, M. L.; Jeys, T. H.; Sickenberger, D. W.; D'Amico, F. M.; Emmons, E. D.; Christesen, S. D.; Kreis, R. J.; Kilper, G. K.

    2017-03-01

    A sensitive chemical aerosol Raman detector (CARD) has been developed for the trace detection and identification of chemical particles in the ambient atmosphere. CARD includes an improved aerosol concentrator with a concentration factor of about 40 and a CCD camera for improved detection sensitivity. Aerosolized isovanillin, which is relatively safe, has been used to characterize the performance of the CARD. The limit of detection (SNR = 10) for isovanillin in 15 s has been determined to be 1.6 pg/cm3, which corresponds to 6.3 × 109 molecules/cm3 or 0.26 ppb. While less sensitive, CARD can also detect gases. This paper provides a more detailed description of the CARD hardware and detection algorithm than has previously been published.

  10. Stratospheric Aerosol Measurements

    Science.gov (United States)

    Pueschel, Rudolf, F.; Gore, Warren J. (Technical Monitor)

    1998-01-01

    Stratospheric aerosols affect the atmospheric energy balance by scattering and absorbing solar and terrestrial radiation. They also can alter stratospheric chemical cycles by catalyzing heterogeneous reactions which markedly perturb odd nitrogen, chlorine and ozone levels. Aerosol measurements by satellites began in NASA in 1975 with the Stratospheric Aerosol Measurement (SAM) program, to be followed by the Stratospheric Aerosol and Gas Experiment (SAGE) starting in 1979. Both programs employ the solar occultation, or Earth limb extinction, techniques. Major results of these activities include the discovery of polar stratospheric clouds (PSCs) in both hemispheres in winter, illustrations of the impacts of major (El Chichon 1982 and Pinatubo 1991) eruptions, and detection of a negative global trend in lower stratospheric/upper tropospheric aerosol extinction. This latter result can be considered a triumph of successful worldwide sulfur emission controls. The SAGE record will be continued and improved by SAGE III, currently scheduled for multiple launches beginning in 2000 as part of the Earth Observing System (EOS). The satellite program has been supplemented by in situ measurements aboard the ER-2 (20 km ceiling) since 1974, and from the DC-8 (13 km ceiling) aircraft beginning in 1989. Collection by wire impactors and subsequent electron microscopic and X-ray energy-dispersive analyses, and optical particle spectrometry have been the principle techniques. Major findings are: (1) The stratospheric background aerosol consists of dilute sulfuric acid droplets of around 0.1 micrometer modal diameter at concentration of tens to hundreds of monograms per cubic meter; (2) Soot from aircraft amounts to a fraction of one percent of the background total aerosol; (3) Volcanic eruptions perturb the sulfuric acid, but not the soot, aerosol abundance by several orders of magnitude; (4) PSCs contain nitric acid at temperatures below 195K, supporting chemical hypotheses

  11. Automated aerosol Raman spectrometer for semi-continuous sampling of atmospheric aerosol

    Science.gov (United States)

    Doughty, David C.; Hill, Steven C.

    2017-02-01

    Raman spectroscopy (RS) is useful in characterizing atmospheric aerosol. It is not commonly used in studying ambient particles partly because automated instrumentation for aerosol RS has not been available. Battelle (Columbus, Ohio, USA) has developed the Resource Effective Bioidentification System (REBS) for automated detection of airborne bioagents based on RS. We use a version of the REBS that measures Raman spectra of one set of particles while the next set of particles is collected from air, then moves the newly collected particles to the analysis region and repeats. Here we investigate the use of the REBS as the core of a general-purpose automated Aerosol Raman Spectrometer (ARS) for atmospheric applications. This REBS-based ARS can be operated as a line-scanning Raman imaging spectrometer. Spectra measured by this ARS for single particles made of polystyrene, black carbon, and several other materials are clearly distinguishable. Raman spectra from a 15 min ambient sample (approximately 35-50 particles, 158 spectra) were analyzed using a hierarchical clustering method to find that the cluster spectra are consistent with soot, inorganic aerosol, and other organic compounds. The ARS ran unattended, collecting atmospheric aerosol and measuring spectra for a 7 hr period at 15-min intervals. A total of 32,718 spectra were measured; 5892 exceeded a threshold and were clustered during this time. The number of particles exhibiting the D-G bands of amorphous carbon plotted vs time (at 15-min intervals) increases during the morning commute, then decreases. This data illustrates the potential of the ARS to measure thousands of time resolved aerosol Raman spectra in the ambient atmosphere over the course of several hours. The capability of this ARS for automated measurements of Raman spectra should lead to more extensive RS-based studies of atmospheric aerosols.

  12. Aerosol generation by blower motors as a bias in assessing aerosol penetration into cabin filtration systems.

    Science.gov (United States)

    Heitbrink, William A; Collingwood, Scott

    2005-01-01

    In cabin filtration systems, blower motors pressurize a vehicle cabin with clean filtered air and recirculate air through an air-conditioning evaporator coil and a heater core. The exposure reduction offered by these cabins is evaluated by optical particle counters that measure size-dependent aerosol concentration inside and outside the cabin. The ratio of the inside-to-outside concentration is termed penetration. Blower motors use stationary carbon brushes to transmit an electrical current through a rotating armature that abrades the carbon brushes. This creates airborne dust that may affect experimental evaluations of aerosol penetration. To evaluate the magnitude of these dust emissions, blower motors were placed in a test chamber and operated at 12 and 13.5 volts DC. A vacuum cleaner drew 76 m3/hour (45 cfm) of air through HEPA filters, the test chamber, and through a 5 cm diameter pipe. An optical particle counter drew air through an isokinetic sampling probe and measured the size-dependent particle concentrations from 0.3 to 15 microm. The concentration of blower motor aerosol was between 2 x 10(5) and 1.8 x 10(6) particles/m3. Aerosol penetration into three stationary vehicles, two pesticide application vehicles and one tractor were measured at two conditions: low concentration (outside in the winter) and high concentration (inside repair shops and burning incense sticks used as a supplemental aerosol source). For particles smaller than 1 microm, the in-cabin concentrations can be explained by the blower motor emissions. For particles larger than 1 microm, other aerosol sources, such as resuspended dirt, are present. Aerosol generated by the operation of the blower motor and by other sources can bias the exposure reduction measured by optical particle counters.

  13. Reallocation in modal aerosol models: impacts on predicting aerosol radiative effects

    Directory of Open Access Journals (Sweden)

    T. Korhola

    2013-08-01

    Full Text Available 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 climatologically relevant parameters: cloud droplet number concentration, aerosol-cloud interaction coefficient and light extinction coefficient. We compared these parameters between a modal model with and without reallocation routines, and a high resolution sectional model that was considered as a reference model. We analysed the relative differences of the parameters in different experiments that were designed to cover a wide range of dynamic aerosol processes occurring in the atmosphere. According to our results, limiting the allowed size ranges of the modes and the following numerical remapping of the distribution by reallocation, leads on average to underestimation of cloud droplet number concentration (up to 100% and overestimation of light extinction (up to 20%. The analysis of aerosol first indirect effect is more complicated as the ACI parameter can be either over- or underestimated by the reallocating model, depending on the conditions. However, for example in the case of atmospheric new particle formation events followed by rapid particle growth, the reallocation can cause around average 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.

  14. Use of the CALIOP vertical feature mask for evaluating global aerosol models

    Directory of Open Access Journals (Sweden)

    E. P. Nowottnick

    2015-01-01

    Full Text Available Global aerosol distributions provided by the NASA Modern Era Retrospective Analysis for Research and Applications aerosol reanalysis (MERRAero are evaluated using the aerosol types identified by the CALIOP vertical feature mask (VFM algorithm, focusing especially on Saharan dust distributions during July 2009. MERRAero is comprised of an aerosol simulation produced in the Goddard Earth Observing System version 5 (GEOS-5 Earth system model and incorporates assimilation of MODIS-derived aerosol optical thickness to constrain column aerosol loadings. For comparison to the CALIOP VFM we construct two synthetic VFMs using the MERRAero aerosol distributions: a Level 2 VFM in which simulated MERRAero total attenuated backscatter and estimated particulate depolarization ratios are input directly to the CALIOP VFM typing algorithm, and a Level 3 VFM in which we map the aerosol species in MERRAero to the CALIOP VFM types. By comparing the simulated MERRAero-Level 2 VFM to CALIOP VFM we can diagnose the aerosol transport and speciation in MERRAero. By comparing the MERRAero-Level 2 and MERRAero-Level 3 simulated VFMs we perform a simple Observing System Simulation Experiment (OSSE, which is useful for identifying shortcomings in the CALIOP VFM algorithm itself. We find that despite having our column AOT constrained by MODIS, comparison to the CALIOP VFM reveals a greater occurrence of dusty aerosol layers in our MERRAero-Level 2 VFM, due to errors in MERRAero aerosol speciation. Additionally, we find that the CALIOP VFM algorithm classification for desert dust and polluted dust should be reconsidered for aerosol features that contain dust mixtures in low aerosol loadings, as our application of the CALIOP VFM to MERRAero distributions flagged a greater presence of dusty vs. marine aerosols when our two MERRAero VFMs were compared.

  15. SoFi, an Igor based interface for the efficient use of the generalized multilinear engine (ME-2 for source apportionment: application to aerosol mass spectrometer data

    Directory of Open Access Journals (Sweden)

    F. Canonaco

    2013-07-01

    Full Text Available Source apportionment using the bilinear model through the multilinear engine (ME-2 was successfully applied to non-refractory organic aerosol (OA mass spectra collected during winter 2011 and 2012 in Zurich, Switzerland using the aerosol chemical speciation monitor ACSM. Five factors were identified: low-volatility oxygenated OA (LV-OOA, semivolatile oxygenated OA (SV-OOA, hydrocarbon-like OA (HOA, cooking OA (COA and biomass burning OA (BBOA. A graphical user interface SoFi (Source Finder was developed at PSI in order to facilitate the testing of different rotational techniques available within the ME-2 engine by providing a priori factor profiles for some or all of the expected factors. ME-2 was used to test the positive matrix factorization (PMF model, the fully constrained chemical mass balance (CMB model, and partially constrained models utilizing a values and pulling equations. Within the set of model solutions determined to be environmentally reasonable, BBOA and SV-OOA factor mass spectra and time series showed the greatest variability. This variability represents uncertainty in the model solution and indicates that analysis of model rotations provides a useful approach for assessing the uncertainty of bilinear source apportionment models.

  16. CU AMAX-DOAS applications in cloud-free and cloudy atmospheres: innovative Scattered Sun Light observations of trace gases and aerosol extinction

    Science.gov (United States)

    Volkamer, R.; Baidar, S.; Coburn, S.; Dix, B. K.; Oetjen, H.; Ortega, I.; Sinreich, R.; Atmospeclab

    2011-12-01

    An innovative airborne scanning multi-axis differential optical absorption spectroscopy (CU AMAX-DOAS) instrument has been developed at the University of Colorado, Boulder. The instrument collects scattered sunlight spectra in a sequence of discrete viewing angles, and employs the DOAS method (inherently calibrated, and selective) to simultaneously retrieve multiple trace gases, e.g., nitrogen dioxide (NO2), nitrous acid (HONO), formaldehyde (HCHO), glyoxal (CHOCHO), bromine oxide (BrO), iodine oxide (IO), chlorine dioxide (OClO), water vapor (H2O), and oxygen dimers (O4, at 360nm, 477nm, and 632nm) differential slant column densities (dSCD). Vertical profiles of these gases and multi-spectral aerosol extinction are inferred by combining Monte-Carlo Radiative Transfer Modelling (RTM) and optimal estimation techniques to construct a model atmosphere that can in principle represent 3D clouds and aerosols. The atmospheric state of this model atmosphere is constrained by observations of O4 dSCDs, Raman Scattering Probability (RSP), and intensity ratios, i.e., quantities that depend solely on relative intensity changes, without need for a direct sun view, or absolute radiance calibration. We show results from ongoing validation efforts (NOAA TwinOtter aircraft during CalNex and CARES), and demonstrate vertical profile retrievals (NSF/NCAR GV over the tropical Pacific Ocean) in both cloud-free and cloudy atmospheres.

  17. Detection of biological aerosols by luminescence techniques

    Science.gov (United States)

    Stopa, Peter J.; Tieman, Darlene; Coon, Phillip A.; Paterno, Dorothea A.; Milton, Maurice M.

    1999-12-01

    Luciferin-Luciferase (L-L) luminescence techniques were used to successfully measure adenosine triphosphate (ATP) (pg/ml) in concentrated aerosol samples containing either vegetative bacterial cells or spores. Aerosols were collected with wet and dry sampling devices. Evaluation for the presence of total bio-mass from bacterial and non-bacterial sources of ATP was achieved by suspending the collected aerosol samples in phosphate buffered saline (PBS), pipeting a 50-(mu) l aliquot of the PBS suspension into a FiltravetteTM, and then adding bacterial releasing agent (BRA). The sample was then reacted with L-L, and the resulting Relative Luminescence Units (RLU's), indicative of ATP from all sources, were measured. Bacterial cells were enumerated with the additional application of a wash with somatic cell releasing agent (SRA) to remove any interferences and non-bacterial sources of ATP prior to BRA application. This step removes interfering substances and non-bacterial sources of ATP. For spore analysis, an equi-volume sample of the PBS suspension was added to an equi-volume of trypticase soy broth (TSB), incubated at 37 C for 15 minutes, and processed using methods identical to bacterial cell analysis. Using these technique we were able to detect Bacillus subtilin variation niger, formerly known as Bacillus globigii (BG), in aerosol samples at concentrations greater than or equal to 105 colony forming units (CFU) per ml. Results of field and chamber trials show that one can detect the presence of bacterial and non-bacterial sources of ATP. One can also differentiate spore and vegetative bacterial cells. These techniques may be appropriate to situations where the measurement of bacterial aerosols is needed.

  18. Aerosol absorption measurement with a sinusoidal phase modulating fiber optic photo thermal interferometer

    Science.gov (United States)

    Li, Shuwang; Shao, Shiyong; Mei, Haiping; Rao, Ruizhong

    2016-10-01

    Aerosol light absorption plays an important role in the earth's atmosphere direct and semi-direct radiate forcing, simultaneously, it also has a huge influence on the visibility impairment and laser engineering application. Although various methods have been developed for measuring aerosol light absorption, huge challenge still remains in precision, accuracy and temporal resolution. The main reason is that, as a part of aerosol light extinction, aerosol light absorption always generates synchronously with aerosol light scattering, and unfortunately aerosol light scattering is much stronger in most cases. Here, a novel photo-thermal interferometry is proposed only for aerosol absorption measurement without disturbance from aerosol scattering. The photo-thermal interferometry consists of a sinusoidal phase-modulating single mode fiber-optic interferometer. The thermal dissipation, caused by aerosol energy from photo-thermal conversion when irritated by pump laser through interferometer, is detected. This approach is completely insensitive to aerosol scattering, and the single mode fiber-optic interferometer is compact, low-cost and insensitive to the polarization shading. The theory of this technique is illustrated, followed by the basic structure of the sinusoidal phase-modulating fiber-optic interferometer and demodulation algorithms. Qualitative and quantitative analysis results show that the new photo-thermal interference is a potential approach for aerosol absorption detection and environmental pollution detection.

  19. Theoretical studies on aerosol agglomeration processes

    Energy Technology Data Exchange (ETDEWEB)

    Lehtinen, K.E.J. [VTT Energy, Espoo (Finland). Energy Use

    1997-12-31

    In this thesis, theoretical modeling of certain aerosol systems has been presented. At first, the aerosol general dynamic equation is introduced, along with a discretization routine for its numerical solution. Of the various possible phenomena affecting aerosol behaviour, this work is mostly focused on aerosol agglomeration. The fundamentals of aerosol agglomeration theory are thus briefly reviewed. The two practical applications of agglomeration studied in this thesis are flue gas cleaning using an electrical agglomerator and nanomaterial synthesis with a free jet reactor. In an electrical agglomerator the aerosol particles are charged and brought into an alternating electric field. The aim is to remove submicron particles from flue gases by collisions with larger particles before conventional gas cleaning devices that have a clear penetration window in the problematic 0.1-1{mu}m size range. A mathematical model was constructed to find out the effects of the different system parameters on the agglomerator`s performance. A crucial part of this task was finding out the collision efficiencies of particles of varying size and charge. The original idea was to use unipolar charging of the particles, and a laboratory scale apparatus was constructed for this purpose. Both theory and experiments clearly show that significant removal of submicron particles can not be achieved by such an arrangement. The theoretical analysis further shows that if the submicron particles and the large collector particles were charged with opposite polarity, significant removal of the submicron particles could be obtained. The second application of agglomeration considered in this thesis is predicting/controlling nanoparticle size in the gas-to-particle aerosol route to material synthesis. In a typical material reactor, a precursor vapor reacts to form molecules of the desired material. In a cooling environment, a particulate phase forms, the dynamics of which are determined by the rates of

  20. Global 2-D intercomparison of sectional and modal aerosol modules

    Directory of Open Access Journals (Sweden)

    D. K. Weisenstein

    2007-01-01

    Full Text Available We present an intercomparison of several aerosol modules, sectional and modal, in a global 2-D model in order to differentiate their behavior for tropospheric and stratospheric applications. We model only binary sulfuric acid-water aerosols in this study. Three versions of the sectional model and three versions of the modal model are used to test the sensitivity of background aerosol mass and size distribution to the number of bins or modes and to the prescribed width of the largest mode. We find modest sensitivity to the number of bins (40 vs. 150 used in the sectional model. Aerosol mass is found to be reduced in a modal model if care is not taken in selecting the width of the largest lognormal mode, reflecting differences in sedimentation in the middle stratosphere. The size distributions calculated by the sectional model can be better matched by a modal model with four modes rather than three modes in most but not all situations. A simulation of aerosol decay following the 1991 eruption of Mt. Pinatubo shows that the representation of the size distribution can have a signficant impact on model-calculated aerosol decay rates in the stratosphere. Between 1991 and 1995, aerosol extinction and surface area density calculated by two versions of the modal model adequately match results from the sectional model. Calculated effective radius for the same time period shows more intermodel variability, with a 20-bin sectional model performing much better than any of the modal models.

  1. ISS Ambient Air Quality: Updated Inventory of Known Aerosol Sources

    Science.gov (United States)

    Meyer, Marit

    2014-01-01

    Spacecraft cabin air quality is of fundamental importance to crew health, with concerns encompassing both gaseous contaminants and particulate matter. Little opportunity exists for direct measurement of aerosol concentrations on the International Space Station (ISS), however, an aerosol source model was developed for the purpose of filtration and ventilation systems design. This model has successfully been applied, however, since the initial effort, an increase in the number of crewmembers from 3 to 6 and new processes on board the ISS necessitate an updated aerosol inventory to accurately reflect the current ambient aerosol conditions. Results from recent analyses of dust samples from ISS, combined with a literature review provide new predicted aerosol emission rates in terms of size-segregated mass and number concentration. Some new aerosol sources have been considered and added to the existing array of materials. The goal of this work is to provide updated filtration model inputs which can verify that the current ISS filtration system is adequate and filter lifetime targets are met. This inventory of aerosol sources is applicable to other spacecraft, and becomes more important as NASA considers future long term exploration missions, which will preclude the opportunity for resupply of filtration products.

  2. Characterization of secondary aerosol and its extinction effects on visibility over the Pearl River Delta Region, China.

    Science.gov (United States)

    Deng, Xuejiao; Wu, Dui; Yu, Jianzhen; Lau, Alexis K H; Li, Fei; Tan, Haobo; Yuan, Zibing; Ng, Wai Man; Deng, Tao; Wu, Cheng; Zhou, Xiuji

    2013-09-01

    Aerosol samples collected from July 2007 to March 2008 were used to obtain major aerosol constituents in an urban location in the Pearl River Delta Region (PRD), China. The minimum organic carbon (OC)/elemental carbon (EC) ratio was used to calculate the primary and secondary organic carbon and the extinction effect of the secondary aerosol on visibility was estimated. As indicated in the analysis, the mass of secondary aerosol takes up 50% of the total mass of PM2.5; the OC/EC ratio is larger than 2 and there are significant characteristics of secondary aerosol generation; the levels of secondary OC are comparable with those of sulfate; and there is obvious enrichment of secondary aerosol on more polluted days. In a dry environment, the extinction weight is 59% for the secondary aerosol, while it is as high as 82% if the environment is highly humid (relative humidity [RH] = 95%). The hygroscopic growth of the aerosol can reduce visibility greatly; the secondary aerosol shares much larger quotas on more polluted days. For the Pearl River Delta (PRD), secondary aerosol and carbonaceous aerosol, especially secondary organic carbon (SOC), are a very acute problem; the study of the generating mechanism and sources for secondary aerosol is the key to the effort of controlling visibility in this region. The equation set forth in IMPROVE experiments can only be referenced but is not applicable to evaluate the extinction effect of individual aerosol components on visibility in the PRD region.

  3. La educación física femenina en el período Isabelino (1833-1868) : Teresa Castellanos de Mesa, primera profesora española de gimnástica.

    OpenAIRE

    Torrebadella Flix, Xavier

    2013-01-01

    En el olvido de la educación física de la mujer del siglo XIX se destacó la heroína Teresa Castellanos de Mesa, maestra de esgrimistas y primera profesora española de la educación física. Desde esta posición particular, Castellanos reivindicó ante el reinado de Isabel II (1833-1868) el derecho de las mujeres a robustecerse, hito que la sitúa como pionera en la reivindicación feminista de los ejercicios gimnásticos y deportivos en España. In the oblivion of women's physical education during...

  4. Implementation of road and soil dust emission parameterizations in the aerosol model CAMx: Applications over the greater Athens urban area affected by natural sources

    Science.gov (United States)

    Athanasopoulou, E.; Tombrou, M.; Russell, A. G.; Karanasiou, A.; Eleftheriadis, K.; Dandou, A.

    2010-09-01

    A detailed dust emission parameterization was developed for aerosol production by human and natural activity. The road dust scheme includes tire wear, break wear, road abrasion and vehicle-induced re-suspension. The natural dust scheme includes wind (Aeolian) erosion from soil surfaces and land disturbances, and considers the effects of soil and atmospheric parameters on dust productivity. Emission rates are chemically and size-resolved and are incorporated in the CAMx aerosol model coupled with the ISORROPIA II inorganic module. Emissions and concentrations are predicted for five simulation periods, using a domain covering Greece with a fine mesh over the greater Athens area. Re-suspended mass is the main dust component, calculated 4-5 times higher than exhaust emissions. Soil dust emissions are much greater than road dust during high winds but are of less importance inside the city with maximums located at the periphery of the urban core. Comparison with observations suggests that the road dust component seems adequately estimated in traffic-affected areas and accounts for 15-40% of the total PM10. Calcium, regarded as a soil dust tracer, is calculated to be 2-4 μg m-3 in areas with high Aeolian emission rates, similar to measured values. Sodium and magnesium predictions show their marine origin, and reasonably replicate the observed mass and size distribution during well-established onshore flows. Nitrates are predicted as measured during lower winds, but are underestimated when stronger winds prevail from the west. This is caused by an overestimated industrial influence of Athens. As a result, ammonia is bound to the excess of sulfate, rather than reacting with nitric acid. Secondary species are influenced slightly by heterogeneous chemistry on dust particles.

  5. Toward a combined SAGE II-HALOE aerosol climatology: an evaluation of HALOE version 19 stratospheric aerosol extinction coefficient observations

    Directory of Open Access Journals (Sweden)

    L. W. Thomason

    2012-09-01

    Full Text Available Herein, the Halogen Occultation Experiment (HALOE aerosol extinction coefficient data is evaluated in the low aerosol loading period after 1996 as the first necessary step in a process that will eventually allow the production of a combined HALOE/SAGE II (Stratospheric Aerosol and Gas Experiment aerosol climatology of derived aerosol products including surface area density. Based on these analyses, it is demonstrated that HALOE's 3.46 μm is of good quality above 19 km and suitable for scientific applications above that altitude. However, it is increasingly suspect at lower altitudes and should not be used below 17 km under any circumstances after 1996. The 3.40 μm is biased by about 10% throughout the lower stratosphere due to the failure to clear NO2 but otherwise appears to be a high quality product down to 15 km. The 2.45 and 5.26 μm aerosol extinction coefficient measurements are clearly biased and should not be used for scientific applications after the most intense parts of the Pinatubo period. Many of the issues in the aerosol data appear to be related to either the failure to clear some interfering gas species or doing so poorly. For instance, it is clear that the 3.40 μm aerosol extinction coefficient measurements can be improved through the inclusion of an NO2 correction and could, in fact, end up as the highest quality overall HALOE aerosol extinction coefficient measurement. It also appears that the 2.45 and 5.26 μm channels may be improved by updating the Upper Atmosphere Pilot Database which is used as a resource for the removal of gas species otherwise not available from direct HALOE measurements. Finally, a simple model to demonstrate the promise of mixed visible/infrared aerosol extinction coefficient ensembles for the retrieval of bulk aerosol properties demonstrates that a combined HALOE/SAGE II aerosol climatology is feasible and may represent a substantial improvement over independently derived

  6. Infrared remote sensing of atmospheric aerosols; Apports du sondage infrarouge a l'etude des aerosols atmospheriques

    Energy Technology Data Exchange (ETDEWEB)

    Pierangelo, C.

    2005-09-15

    The 2001 report from the Intergovernmental Panel on Climate Change emphasized the very low level of understanding of atmospheric aerosol effects on climate. These particles originate either from natural sources (dust, volcanic aerosols...) or from anthropogenic sources (sulfates, soot...). They are one of the main sources of uncertainty on climate change, partly because they show a very high spatio-temporal variability. Observation from space, being global and quasi-continuous, is therefore a first importance tool for aerosol studies. Remote sensing in the visible domain has been widely used to obtain a better characterization of these particles and their effect on solar radiation. On the opposite, remote sensing of aerosols in the infrared domain still remains marginal. Yet, not only the knowledge of the effect of aerosols on terrestrial radiation is needed for the evaluation of their total radiative forcing, but also infrared remote sensing provides a way to retrieve other aerosol characteristics (observations are possible at night and day, over land and sea). In this PhD dissertation, we show that aerosol optical depth, altitude and size can be retrieved from infrared sounder observations. We first study the sensitivity of aerosol optical properties to their micro-physical properties, we then develop a radiative transfer code for scattering medium adapted to the very high spectral resolution of the new generation sounder NASA-Aqua/AIRS, and we finally focus on the inverse problem. The applications shown here deal with Pinatubo stratospheric volcanic aerosol, observed with NOAA/HIRS, and with the building of an 8 year climatology of dust over sea and land from this sounder. Finally, from AIRS observations, we retrieve the optical depth at 10 {mu}m, the average altitude and the coarse mode effective radius of mineral dust over sea. (author)

  7. Sea Spray Aerosols

    DEFF Research Database (Denmark)

    Butcher, Andrew Charles

    a relationship between plunging jet particle ux, oceanic particle ux, and energy dissipation rate in both systems. Previous sea spray aerosol studies dissipate an order of magnitude more energy for the same particle ux production as the open ocean. A scaling factor related to the energy expended in air...... 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...... jet in high concentrations of surface active organics and brackish water salinities. The jet produces particles with less cloud condensation activity, implying an increase in organic material in aerosol particles produced by the plunging jet over the frit. In the second paper we determine...

  8. 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.

  9. 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.

  10. Acidic aerosol in urban air

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, M.; Yamaoka, S.; Miyazaki, T.; Oka, M.

    1982-01-01

    The distribution and chemical composition of acidic aerosol in Osaka City were investigated. Samples were collected at five sites in the city from June to September, 1979. Acidic aerosol was determined by the acid-base titration method, sulfate ion by barium chloride turbidimetry, nitrate ion by the xylenol method, and chloride ion by the mercury thiocyanate method. The concentration of acidic aerosol at five sites ranged from 7.7 micrograms per cubic meter to 10.0 micrograms per cubic meter, but mean concentrations in the residential area were slightly higher than those in the industrial area. When acidic aerosol concentrations were compared with concentrations of sulfate, nitrate, and chloride ions, a significant correlation was found between acidic aerosol and sulfate ion. The sum of the ion equivalents of the three types showed good correlation with the acidic aerosol equivalent during the whole period.

  11. Comprehensive tool for calculation of radiative fluxes: illustration of shortwave aerosol radiative effect sensitivities to the details in aerosol and underlying surface characteristics

    Science.gov (United States)

    Derimian, Yevgeny; Dubovik, Oleg; Huang, Xin; Lapyonok, Tatyana; Litvinov, Pavel; Kostinski, Alex B.; Dubuisson, Philippe; Ducos, Fabrice

    2016-05-01

    of SZAs, the errors vary with latitude and season. In summary, the present analysis showed that use of simplified assumptions causes systematic biases, rather than random uncertainties, in calculation of both instantaneous and daily average aerosol radiative effect. Finally, we illustrate application of the rigorous aerosol radiative effect calculations performed as part of GRASP aerosol retrieval from real POLDER/PARASOL satellite observations.

  12. Lagrangian Displacement Ensembles for Aerosol Data Assimilation (Invited)

    Science.gov (United States)

    da Silva, A.; Colarco, P. R.; Govindaraju, R. C.

    2010-12-01

    A challenge common to many constituent data assimilation applications is the fact that one observes a much smaller fraction of the phase space that one wishes to estimate. For example, remotely-sensed estimates of the column average concentrations are available, while one is faced with the problem of estimating 3D concentractions for initializing a prognostic model. This problem is exarcebated in the the case of aerosols because the observable Aerosol Optical Depth (AOD) is not only a column integrated quantity, but it also sums over a large number of species (dust, sea-salt, carbonaceous and sulfate aerosols). An aerosol transport model when driven by high-resolution, state-of-the-art analysis of meterorological fields and realistc emissions can produce skillful forecasts even when no aerosol data is assimilated. The main task of aerosol data assimilation is to address the bias arising from innacurate emissions, and the Lagrangian misplacement of plumes induced by errors in the driving meterorological fields. As long as one decouples the meteorological and aerosol assimilation as we do here, the classic baroclinic growth of errors is no longer the main order of business. We will describe and aerosol data assimilation scheme in which the anaysis update step is conducted in observation space, using an adaptive maximum-likelihood scheme for estimating background errors in AOD space. This scheme includes explicit sequential bias estimation as in Dee and da Silva (1998). Unlikely existing aerosol data assimiltion schemes we do not obtain analysis increments of the 3D concentrations by scalling the background profiles. Instead, we explore the Langrangian characteristics of the problem for generating local displacement ensembles. These high-resolution, state-dependent ensembles are then used to parameterize the background errors and generate 3D aerosol increments. The algorithm has computational complexity comparable to the forecasting step by the aerosol transport model

  13. AERONET-based microphysical and optical properties of smoke-dominated aerosol near source regions and transported over oceans, and implications for satellite retrievals of aerosol optical depth

    Science.gov (United States)

    Sayer, A. M.; Hsu, N. C.; Eck, T. F.; Smirnov, A.; Holben, B. N.

    2013-09-01

    Smoke aerosols from biomass burning are an important component of the global aerosol cycle. Analysis of Aerosol Robotic Network (AERONET) retrievals of size distribution and refractive index reveals variety between biomass burning aerosols in different global source regions, in terms of aerosol particle size and single scatter albedo (SSA). Case studies of smoke transported to coastal/island AERONET sites also mostly lie within the range of variability at near-source sites. Two broad ''families'' of aerosol properties are found, corresponding to sites dominated by boreal forest burning (larger, broader fine mode, with midvisible SSA ∼0.95), and those influenced by grass, shrub, or crop burning with additional forest contributions (smaller, narrower particles with SSA ∼0.88-0.9 in the midvisible). The strongest absorption is seen in southern African savannah at Mongu (Zambia), with average SSA ∼0.85 in the midvisible. These can serve as candidate sets of aerosol microphysical/optical properties for use in satellite aerosol optical depth (AOD) retrieval algorithms. The models presently adopted by these algorithms over ocean are often insufficiently absorbing to represent these biomass burning aerosols. A corollary of this is an underestimate of AOD in smoke outflow regions, which has important consequences for applications of these satellite datasets.

  14. 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

  15. Single-tracer technique to evaluate pulmonary edema and its application to detect the effect of hexamethylene diisocyanate trimer aerosol exposures

    Energy Technology Data Exchange (ETDEWEB)

    Valentini, J.E.; Wong, K.L.; Alarie, Y.

    1983-07-01

    Two hours after a four-hour exposure to hexamethylene diisocyanate trimer (HDIt) aerosol between 2.5 and 39 mg/m3, mice were injected iv with /sup 51/Cr-EDTA (chromium ethylenediaminetetraacetate). Ten minutes later the lung was lavaged. A larger amount of /sup 51/Cr-EDTA was detected in the lung lavage of HDIt mice than of controls in a concentration-related fashion. The concentration-response curve was shifted to the left compared with that constructed using lung weight increase as response. Kinetic studies of the plasma level of /sup 51/Cr-EDTA revealed a three-exponential profile in normal mice, and similar plasma levels were obtained with mice exposed to 18-24 mg/m3 HDIt. However, both the amount of /sup 51/Cr-EDTA in the alveolar space and concentration in the pulmonary extravascular compartment were higher in HDIt-exposed mice than in controls. The data of /sup 51/Cr-EDTA distribution in the lung were fitted with a three-compartment model. According to the model, HDIt exposures increase the permeability constants of /sup 51/Cr-EDTA transport into the alveolar space from blood which accounts for the larger amount of /sup 51/Cr-EDTA in lung lavage of HDIt-exposed mice. This /sup 51/Cr-EDTA injection and lung lavage technique is a sensitive method for detecting pulmonary edema.

  16. Laboratory and field measurements of organic aerosols with the photoionization aerosol mass spectrometer

    Science.gov (United States)

    Dreyfus, Matthew A.

    Analytical methods developed to sample and characterize ambient organic aerosols often face the trade-off between long sampling times and the loss of detailed information regarding specific chemical species present. The soft, universal ionization scheme of the Photoionization Aerosol Mass Spectrometer (PIAMS) allows for identification of various chemical compounds by a signature ion, often the molecular ion. The goal of this thesis work is to apply PIAMS to both laboratory and field experiments to answer questions regarding the formation, composition, and behavior of organic aerosols. To achieve this goal, a variety of hardware and software upgrades were administered to PIAMS to optimize the instrument. Data collection and processing software were either refined or built from the ground up to simplify difficult or monotonous tasks. Additional components were added to PIAMS with the intent to automate the instrument, enhance the results, and make the instrument more rugged and user-friendly. These changes, combined with the application of an external particle concentration system (mini-Versatile Aerosol Concentration Enrichment System, m-VACES), allowed PIAMS to be suitable for field measurements of organic aerosols. Two such field campaigns were completed, both at the State of Delaware Air Quality Monitoring Site in Wilmington, Delaware: a one week period in June, 2006, and an 18 day period in October and November of 2007. A sampling method developed was capable of collecting sufficient ambient organic aerosol and analyzing it with a time resolution of 3.5 minutes. Because of this method, short term concentration changes of individual species can be tracked. Combined with meteorological data, the behavior of these species can be analyzed as a function of time or wind direction. Many compounds are found at enhanced levels during the evening/night-time hours; potentially due to the combined effects of temperature inversion, and fresh emissions in a cooler environment

  17. The online chemical analysis of single particles using aerosol beams and time of flight mass spectroscopy

    NARCIS (Netherlands)

    Kievit, O.; Weiss, M.; Verheijen, P.J.T.; Marijnissen, J.C.M.; Scarlett, B.

    This paper describes an on-line instrument, capable of measuring the size and chemical composition of single aerosol particles. Possible applications include monitoring aerosol reactors and studying atmospheric chemistry. The main conclusion is that a working prototype has been built and tested. It

  18. Aerosol absorption and radiative forcing

    Directory of Open Access Journals (Sweden)

    P. Stier

    2007-05-01

    Full Text Available We present a comprehensive examination of aerosol absorption with a focus on evaluating the sensitivity of the global distribution of aerosol absorption to key uncertainties in the process representation. For this purpose we extended the comprehensive aerosol-climate model ECHAM5-HAM by effective medium approximations for the calculation of aerosol effective refractive indices, updated black carbon refractive indices, new cloud radiative properties considering the effect of aerosol inclusions, as well as by modules for the calculation of long-wave aerosol radiative properties and instantaneous aerosol forcing. The evaluation of the simulated aerosol absorption optical depth with the AERONET sun-photometer network shows a good agreement in the large scale global patterns. On a regional basis it becomes evident that the update of the BC refractive indices to Bond and Bergstrom (2006 significantly improves the previous underestimation of the aerosol absorption optical depth. In the global annual-mean, absorption acts to reduce the short-wave anthropogenic aerosol top-of-atmosphere (TOA radiative forcing clear-sky from –0.79 to –0.53 W m−2 (33% and all-sky from –0.47 to –0.13 W m−2 (72%. Our results confirm that basic assumptions about the BC refractive index play a key role for aerosol absorption and radiative forcing. The effect of the usage of more accurate effective medium approximations is comparably small. We demonstrate that the diversity in the AeroCom land-surface albedo fields contributes to the uncertainty in the simulated anthropogenic aerosol radiative forcings: the usage of an upper versus lower bound of the AeroCom land albedos introduces a global annual-mean TOA forcing range of 0.19 W m−2 (36% clear-sky and of 0.12 W m−2 (92% all-sky. The consideration of black carbon inclusions on cloud radiative properties results in a small global annual-mean all-sky absorption of 0.05 W

  19. Hand calculations for transport of radioactive aerosols through sampling systems.

    Science.gov (United States)

    Hogue, Mark; Thompson, Martha; Farfan, Eduardo; Hadlock, Dennis

    2014-05-01

    Workplace air monitoring programs for sampling radioactive aerosols in nuclear facilities sometimes must rely on sampling systems to move the air to a sample filter in a safe and convenient location. These systems may consist of probes, straight tubing, bends, contractions and other components. Evaluation of these systems for potential loss of radioactive aerosols is important because significant losses can occur. However, it can be very difficult to find fully described equations to model a system manually for a single particle size and even more difficult to evaluate total system efficiency for a polydispersed particle distribution. Some software methods are available, but they may not be directly applicable to the components being evaluated and they may not be completely documented or validated per current software quality assurance requirements. This paper offers a method to model radioactive aerosol transport in sampling systems that is transparent and easily updated with the most applicable models. Calculations are shown with the R Programming Language, but the method is adaptable to other scripting languages. The method has the advantage of transparency and easy verifiability. This paper shows how a set of equations from published aerosol science models may be applied to aspiration and transport efficiency of aerosols in common air sampling system components. An example application using R calculation scripts is demonstrated. The R scripts are provided as electronic attachments.

  20. Estimation of aerosol optical properties from all-sky imagers

    Science.gov (United States)

    Kazantzidis, Andreas; Tzoumanikas, Panagiotis; Salamalikis, Vasilios; Wilbert, Stefan; Prahl, Christoph

    2015-04-01

    Aerosols are one of the most important constituents in the atmosphere that affect the incoming solar radiation, either directly through absorbing and scattering processes or indirectly by changing the optical properties and lifetime of clouds. Under clear skies, aerosols become the dominant factor that affect the intensity of solar irradiance reaching the ground. It has been shown that the variability in direct normal irradiance (DNI) due to aerosols is more important than the one induced in global horizontal irradiance (GHI), while the uncertainty in its calculation is dominated by uncertainties in the aerosol optical properties. In recent years, all-sky imagers are used for the detection of cloud coverage, type and velocity in a bouquet of applications including solar irradiance resource and forecasting. However, information about the optical properties of aerosols could be derived with the same instrumentation. In this study, the aerosol optical properties are estimated with the synergetic use of all-sky images, complementary data from the Aerosol Robotic Network (AERONET) and calculations from a radiative transfer model. The area of interest is Plataforma Solar de Almería (PSA), Tabernas, Spain and data from a 5 month period are analyzed. The proposed methodology includes look-up-tables (LUTs) of diffuse sky radiance of Red (R), Green (G) and Blue (B) channels at several zenith and azimuth angles and for different atmospheric conditions (Angström α and β, single scattering albedo, precipitable water, solar zenith angle). Based on the LUTS, results from the CIMEL photometer at PSA were used to estimate the RGB radiances for the actual conditions at this site. The methodology is accompanied by a detailed evaluation of its robustness, the development and evaluation of the inversion algorithm (derive aerosol optical properties from RGB image values) and a sensitivity analysis about how the pre-mentioned atmospheric parameters affect the results.

  1. Production of satellite-derived aerosol climate data records: current status of the ESA Aerosol_cci project

    Science.gov (United States)

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

    2015-04-01

    and the Aerosol_cci team Within the ESA Climate Change Initiative (CCI) project Aerosol_cci (Phase 1: 2010 -2014; Phase 2: 2014-2017) intensive work has been conducted to improve algorithms for the retrieval of aerosol information from European sensors ATSR (3 algorithms), PARASOL, MERIS (3 algorithms), synergetic AATSR/SCIAMACHY, OMI and GOMOS. Whereas OMI and GOMOS were used to derive absorbing aerosol index and stratospheric extinction profiles, respectively, Aerosol Optical Depth (AOD) and Ångström coefficient were retrieved from the other sensors. The cooperation between the project partners, including both the retrieval teams and independent validation teams, has resulted in a strong improvement of most algorithms. In particular the AATSR retrieved AOD is qualitatively similar to that from MODIS, usually taken as the standard, MISR and SeaWiFS. This conclusion has been reached form several different ways of validation of the L2 and L3 products, using AERONET sun photometer data as the common ground-truth for the application of both 'traditional' statistical techniques and a 'scoring' technique using spatial and temporal correlations. Quantitatively, the limited AATSR swath width of 500km results in a smaller amount of data. Nevertheless, the assimilation of AATSR-retrieved AOD, together with MODIS data, contributes to improving the in the ECMWF climate model results. In addition to the multi-spectral AOD, and thus the Ångström Exponent, also a per-pixel uncertainty is provided and validated. By the end of Aerosol_cci Phase 1 the ATSR algorithms have been applied to both ATSR-2 and AATSR resulting in an AOD time series of 17 years. In phase 2 this work is continued with a focus on the further improvement of the ATSR algorithms as well as those for the other instruments and algorithms, mentioned above, which in phase 1 were considered less mature. The first efforts are on the further characterization of the uncertainties and on better understanding of the

  2. Dust aerosol impact on North Africa climate: a GCM investigation of aerosol-cloud-radiation interactions using A-Train satellite data

    Directory of Open Access Journals (Sweden)

    Y. Gu

    2012-02-01

    Full Text Available The climatic effects of dust aerosols in North Africa have been investigated using the atmospheric general circulation model (AGCM developed at the University of California, Los Angeles (UCLA. The model includes an efficient and physically based radiation parameterization scheme developed specifically for application to clouds and aerosols. Parameterization of the effective ice particle size in association with the aerosol first indirect effect based on ice cloud and aerosol data retrieved from A-Train satellite observations have been employed in climate model simulations. Offline simulations reveal that the direct solar, IR, and net forcings by dust aerosols at the top of the atmosphere (TOA generally increase with increasing aerosol optical depth. When the dust semi-direct effect is included with the presence of ice clouds, positive IR radiative forcing is enhanced since ice clouds trap substantial IR radiation, while the positive solar forcing with dust aerosols alone has been changed to negative values due to the strong reflection of solar radiation by clouds, indicating that cloud forcing associated with aerosol semi-direct effect could exceed direct aerosol forcing. With the aerosol first indirect effect, the net cloud forcing is generally reduced in the case for an ice water path (IWP larger than 20 g m−2. The magnitude of the reduction increases with IWP.

    AGCM simulations show that the reduced ice crystal mean effective size due to the aerosol first indirect effect results in less OLR and net solar flux at TOA over the cloudy area of the North Africa region because ice clouds with smaller size trap more IR radiation and reflect more solar radiation. The precipitation in the same area, however, increases due to the aerosol indirect effect on ice clouds, corresponding to the enhanced convection as indicated by reduced OLR. Adding the aerosol direct effect into the model simulation reduces the precipitation in the

  3. Annual cycle of Antarctic baseline aerosol: controlled by photooxidation-limited aerosol formation

    Directory of Open Access Journals (Sweden)

    M. Fiebig

    2013-09-01

    Full Text Available This article investigates the annual cycle observed in the Antarctic baseline aerosol scattering coefficient, total particle number concentration, and particle number size distribution (PNSD as measured at Troll Atmospheric Observatory. Mie-theory shows that the annual cycles in microphysical and optical aerosol properties have a common cause. By comparison with observations at other Antarctic stations, it is shown that the annual cycle is not a local phenomenon, but common to Central Antarctic baseline air masses. Observations of ground-level ozone at Troll as well as backward plume calculations for the air masses arriving at Troll demonstrate that the baseline air masses originate from the free troposphere and lower stratosphere region, and descend over the Central Antarctic continent. The Antarctic summer PNSD is dominated by particles with diameters 3/(MJ m. Further research is proposed to investigate the applicability of this number to other atmospheric reservoirs, and to use the observed annual cycle in Antarctic baseline aerosol properties as a benchmark for the representation of natural atmospheric aerosol processes in climate models.

  4. Modeling the formation and properties of traditional and non-traditional secondary organic aerosol: problem formulation and application to aircraft exhaust

    Directory of Open Access Journals (Sweden)

    S. H. Jathar

    2012-10-01

    Full Text Available We present a methodology to model secondary organic aerosol (SOA formation from the photo-oxidation of unspeciated low-volatility organics (semi-volatile and intermediate volatile organic compounds emitted by combustion systems. It is formulated using the volatility basis-set approach. Unspeciated low-volatility organics are classified by volatility and then allowed to react with the hydroxyl radical. The new methodology allows for larger reductions in volatility with each oxidation step than previous volatility basis set models, which is more consistent with the addition of common functional groups and similar to those used by traditional SOA models. The methodology is illustrated using data collected during two field campaigns that characterized the atmospheric evolution of dilute gas-turbine engine emissions using a smog chamber. In those experiments, photo-oxidation formed a significant amount of SOA, much of which could not be explained based on the emissions of traditional speciated precursors; we refer to the unexplained SOA as non-traditional SOA (NT-SOA. The NT-SOA can be explained by emissions of unspeciated low-volatility organics measured using sorbents. We show that the parameterization proposed by Robinson et al. (2007 is unable to explain the timing of the NT-SOA formation in the aircraft experiments because it assumes a very modest reduction in volatility of the precursors with every oxidation reaction. In contrast the new method better reproduces the NT-SOA formation. The NT-SOA yields estimated for the unspeciated low-volatility organic emissions in aircraft exhaust are similar to literature data for large n-alkanes and other low-volatility organics. The estimated yields vary with fuel composition (Jet Propellent-8 versus Fischer-Tropsch and engine load (ground idle versus non-ground idle. The framework developed here is suitable for modeling SOA formation from emissions from other combustion systems.

  5. Modeling the formation and properties of traditional and non-traditional secondary organic aerosol: problem formulation and application to aircraft exhaust

    Directory of Open Access Journals (Sweden)

    S. H. Jathar

    2012-04-01

    Full Text Available We present a methodology to model secondary organic aerosol (SOA formation from the photo-oxidation of low-volatility organics (semi-volatile and intermediate volatility organic compounds. The model is parameterized and tested using SOA data collected during two field campaigns that characterized the atmospheric evolution of dilute gas-turbine engine emissions using a smog chamber. Photo-oxidation formed a significant amount of SOA, much of which cannot be explained based on the emissions of traditional, speciated precursors; we refer to this as non-traditional SOA (NT-SOA. The NT-SOA can be explained by emissions of low-volatility organic vapors measured using sorbents. Since these vapors could not be speciated, we employ a volatility-based approach to model NT-SOA formation. We show that the method proposed by Robinson et al. (2007 is unable to explain the timing of NT-SOA formation because it assumes a very modest reduction in volatility of the precursors with every oxidation reaction. In contrast, a Hybrid method, similar to models of traditional SOA formation, assumes a larger reduction in volatility with each oxidation step and results in a better reproduction of NT-SOA formation. The NT-SOA yields estimated for the low-volatility organic vapor emissions are similar to literature data for large n-alkanes and other low-volatility organics. The yields vary with fuel composition (JP8 versus Fischer-Tropsch and engine load (idle versus non-idle. These differences are consistent with the expected contribution of high (aromatics and n-alkanes and low (branched alkanes and oxygenated species SOA forming species to the exhaust.

  6. Application of WRF/Chem-MADRID and WRF/Polyphemus in Europe – Part 2: Evaluation of chemical concentrations, sensitivity simulations, and aerosol-meteorology interactions

    Directory of Open Access Journals (Sweden)

    C. Seigneur

    2013-02-01

    better the observations of PM10 concentrations at all sites. The differences between model predictions and observations are mostly caused by inaccurate representations of emissions of gaseous precursors and primary PM species, as well as biases in the meteorological predictions. The differences in model predictions are caused by differences in the heights of the first model layers and thickness of each layer that affect vertical distributions of emissions, model treatments such as dry/wet deposition, heterogeneous chemistry, and aerosol and cloud, as well as model inputs such as emissions of soil dust and sea-salt and chemical boundary conditions of CO and O3 used in both models. WRF/Chem-MADRID shows a higher sensitivity to grid resolution than WRF/Polyphemus at all sites. For both models, the use of a finer grid resolution generally leads to an overall better statistical performance for most variables, with greater spatial details and an overall better agreement in temporal variations and magnitudes at most sites. The use of online BVOC emissions gives better statistical performance for hourly and max 8-h O3 and PM2.5 and generally better agreement with their observed temporal variations at most sites. Because it is an online model, WRF/Chem-MADRID offers the advantage to account for various feedbacks between meteorology and chemical species. The simulations show that aerosol leads to reduced net shortwave radiation fluxes, 2-m temperature, 10-m wind speed, PBL height, and precipitation and increases aerosol optical depth, cloud condensation nuclei, cloud optical depth, and cloud droplet number concentrations over most of the domain. However, this model comparison suggests that atmospheric pollutant concentrations are most sensitive in state-of-the-science air quality models to vertical structure, inputs, and parameterizations for dry/wet removal of gases and particles in the model.

  7. Aerosol dynamics in porous media

    NARCIS (Netherlands)

    Ghazaryan, Lilya

    2014-01-01

    In this thesis, a computational model was developed for the simulation of aerosol formation through nucleation, followed by condensation and evaporation and filtration by porous material. Understanding aerosol dynamics in porous media can help improving engineering models that are used in various in

  8. Development of an aerosol microphysical module: Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS

    Directory of Open Access Journals (Sweden)

    H. Matsui

    2014-04-01

    Full Text Available Number concentrations, size distributions, and mixing states of aerosols are essential parameters for accurate estimation of aerosol direct and indirect effects. In this study, we develop an aerosol module, designated Aerosol Two-dimensional bin module for foRmation and Aging Simulation (ATRAS, that can represent these parameters explicitly by considering new particle formation (NPF, black carbon (BC aging, and secondary organic aerosol (SOA processes. A two-dimensional bin representation is used for particles with dry diameters from 40 nm to 10 μm to resolve both aerosol size (12 bins and BC mixing state (10 bins for a total of 120 bins. The particles with diameters from 1 to 40 nm are resolved using an additional 8 size bins to calculate NPF. The ATRAS module is implemented in the WRF-chem model and applied to examine the sensitivity of simulated mass, number, size distributions, and optical and radiative parameters of aerosols to NPF, BC aging and SOA processes over East Asia during the spring of 2009. BC absorption enhancement by coating materials is about 50% over East Asia during the spring, and the contribution of SOA processes to the absorption enhancement is estimated to be 10–20% over northern East Asia and 20–35% over southern East Asia. A clear north-south contrast is also found between the impacts of NPF and SOA processes on cloud condensation nuclei (CCN concentrations: NPF increases CCN concentrations at higher supersaturations (smaller particles over northern East Asia, whereas SOA increases CCN concentrations at lower supersaturations (larger particles over southern East Asia. Application of ATRAS to East Asia also shows that the impact of each process on each optical and radiative parameter depends strongly on the process and the parameter in question. The module can be used in the future as a benchmark model to evaluate the accuracy of simpler aerosol models and examine interactions between NPF, BC aging, and SOA

  9. 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.

  10. 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.

  11. Assimilation of Polder aerosol optical thickness into LMD2-Inca model in order to study aerosol-climate interactions; Etude des interactions entre aerosols et climat: assimilation des observations spatiales de Polder dans LMDz-Inca

    Energy Technology Data Exchange (ETDEWEB)

    Generoso, S.

    2004-12-15

    Aerosols influence the Earth radiative budget both through their direct (scattering and absorption of solar radiation) and indirect (impacts on cloud microphysics) effects. The anthropogenic perturbation due to aerosol emissions is of the same order of magnitude than the one due to greenhouse gases, but less well known. To improve our knowledge, we need to better know aerosol spatial and temporal distributions. Indeed, aerosol modeling still suffers from large uncertainties in sources and transport, while satellite observations are incomplete (no detection in the presence of clouds, no information on the vertical distribution or on the chemical nature). Moreover, field campaigns are localized in space and time. This study aims to reduce uncertainties in aerosol distributions, developing assimilation of satellite data into a chemical transport model. The basic idea is to combine information obtained from spatial observation (optical thickness) and modeling studies (aerosol types, vertical distribution). In this study, we assimilate data from the POLDER space-borne instrument into the LMDz-INCA model. The results show the advantage of merging information from different sources. In many regions, the method reduces uncertainties on aerosol distribution (reduction of RMS error). An application of the method to the study of aerosol impact on cloud microphysics is shown. (author)

  12. Growing up MODIS: Towards a mature aerosol climate data record

    Science.gov (United States)

    Levy, Robert C.

    2013-05-01

    Aerosols are major players within the Earth's climate system, affecting the radiation budget, clouds and the hydrological cycle. In high concentrations near the surface, aerosols (or particulate matter, PM) affect visibility, impact air quality, and can contribute to poor health. Among others, Yoram Kaufman recognized the importance of aerosols to climate, and helped to design new instrumentation and algorithms to retrieve and quantify global aerosol properties. One instrument, known as the Moderate Imaging Resolution Spectro-radiometer (MODIS), was deployed on the AM-1 satellite (later known as Terra), part of NASA's Earth Observing System (EOS). In 1998, armed with an M.S. and job experience in neither aerosols nor satellites, I was looking for a new job. I somehow found my way to the MODIS Aerosol team. It was only a year before Terra launch, and most major decisions about the MODIS aerosol retrieval algorithms had been finalized. Since then, we worked through launch, initial evaluation of the product with AERONET and field deployments, and continued efforts to understand the product and refine retrieval algorithms. I have had opportunities to participate in field experiments, write papers, and earn my PhD. The "second generation" algorithm for aerosol retrieval over land has been hugely successful. We have collected nearly a half-million collocations with AERONET and other dataseis, made new discoveries, and have contributed to research and operational projects globally. Due to the dedication of the entire team, the MODIS aerosol product now is one of the highlights of NASA's EOS program. It is used for climate research and air quality forecasting, as well for applications not even considered before the MODIS era. More recently, a focus is on stitching the MODIS aerosol product into the "climate data record" (CDR) for global aerosol, determining whether the product has sufficient length, consistency and continuity to determine climate variability and change

  13. Application of spectral analysis techniques to the intercomparison of aerosol data - Part 4: Combined maximum covariance analysis to bridge the gap between multi-sensor satellite retrievals and ground-based measurements

    Science.gov (United States)

    Li, J.; Carlson, B. E.; Lacis, A. A.

    2014-04-01

    The development of remote sensing techniques has greatly advanced our knowledge of atmospheric aerosols. Various satellite sensors and the associated retrieval algorithms all add to the information of global aerosol variability, while well-designed surface networks provide time series of highly accurate measurements at specific locations. In studying the variability of aerosol properties, aerosol climate effects, and constraining aerosol fields in climate models, it is essential to make the best use of all of the available information. In the previous three parts of this series, we demonstrated the usefulness of several spectral decomposition techniques in the analysis and comparison of temporal and spatial variability of aerosol optical depth using satellite and ground-based measurements. Specifically, Principal Component Analysis (PCA) successfully captures and isolates seasonal and interannual variability from different aerosol source regions, Maximum Covariance Analysis (MCA) provides a means to verify the variability in one satellite dataset against Aerosol Robotic Network (AERONET) data, and Combined Principal Component Analysis (CPCA) realized parallel comparison among multi-satellite, multi-sensor datasets. As the final part of the study, this paper introduces a novel technique that integrates both multi-sensor datasets and ground observations, and thus effectively bridges the gap between these two types of measurements. The Combined Maximum Covariance Analysis (CMCA) decomposes the cross covariance matrix between the combined multi-sensor satellite data field and AERONET station data. We show that this new method not only confirms the seasonal and interannual variability of aerosol optical depth, aerosol source regions and events represented by different satellite datasets, but also identifies the strengths and weaknesses of each dataset in capturing the variability associated with sources, events or aerosol types. Furthermore, by examining the spread of

  14. Atmospheric and aerosol chemistry

    Energy Technology Data Exchange (ETDEWEB)

    McNeill, V. Faye [Columbia Univ., New York, NY (United States). Dept. of Chemical Engineering; Ariya, Parisa A. (ed.) [McGill Univ. Montreal, QC (Canada). Dept. of Chemistry; McGill Univ. Montreal, QC (Canada). Dept. of Atmospheric and Oceanic Sciences

    2014-09-01

    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.

  15. Nanocrystalline functional materials and nanocomposites synthesis through aerosol routes

    Directory of Open Access Journals (Sweden)

    Milošević Olivera B.

    2003-01-01

    Full Text Available This paper represents the results of the design of functional nanocrystalline powders and nanocomposites using chemical reactions in aerosols. The process involves ultrasonic aerosol formation (mist generators with the resonant frequencies of 800 kHz, 1.7 and 2.5 MHz from precursor salt solutions and control over the aerosol decomposition in a high-temperature tubular flow reactor. During decomposition, the aerosol droplets undergo evaporation/drying, precipitation and thermolysis in a single-step process. Consequently, spherical, solid, agglomerate-free submicronic particles are obtained. The particle morphology, revealed as a composite structure consisting of primary crystallites smaller than 20 nm was analysed by several methods (XRD, DSC/DTA, SEM, TEM and discussed in terms of precursor chemistry and process parameters. Following the initial attempts, a more detailed aspect of nanocrystalline particle synthesis was demonstrated for the case of nanocomposites based on ZnO-MeO (MeO=Bi Cr+, suitable for electronic applications, as well as an yttrium-aluminum base complex system, suitable for phosphorus applications. The results imply that parts of the material structure responsible for different functional behaviour appear through in situ aerosol synthesis by processes of intraparticle agglomeration, reaction and sintering in the last synthesis stage.

  16. NANOPARTICLE AEROSOL SCIENCE AND TECHNOLOGY:AN OVERVIEW

    Institute of Scientific and Technical Information of China (English)

    Chiu-sen Wang; Sheldon K. Friedlander; Lutz M(a)dler

    2005-01-01

    As a new scientific discipline, nanoparticle aerosol science and technology (NAST) deals with the formation, properties and behavior of nanoparticles in gases. Driven by its practical applications in many different fields, NAST has been undergoing rapid development. A conceptual framework of the discipline, with its own basic principles, experimental methods and computational techniques, is now taking shape. This paper presents an overview of the current status and research needs of the new discipline. The presentation begins with a discourse on the relationship among various particle systems, which occur frequently in nature and industry. The properties and behavior of nanoparticle aerosols are then discussed, with emphasis on the key roles played by particle size and morphology. Similar to fluid dynamics, NAST is an enabling discipline in the sense that it has provided the concepts and methodology needed for the development of many other fields. Applications of nanoparticle aerosol science and technology are highlighted in three important areas: (1) aerosol processes for synthesis of nanoparticles, (2) atmospheric nanoparticles and global climate,and (3) dosimetry of inhaled nanoparticles. These fields have features in common insofar as nanoparticle aerosols follow the same basic laws of physics and chemistry.

  17. Impact of aerosols on precipitation from deep convective clouds in eastern China

    Science.gov (United States)

    Jiang, Mengjiao; Li, Zhanqing; Wan, Bingcheng; Cribb, Maureen

    2016-08-01

    We analyzed the impact of aerosols on precipitation based on 3 years of 3-hourly observations made in heavily polluted eastern China. The probability of precipitation from different cloud types was calculated using International Satellite Cloud Climatology Project cloud data and gauge-based hourly precipitation data. Because deep convective clouds have the largest precipitation probability, the influence of aerosols on the precipitation from such clouds was studied in particular. Aerosol properties were taken from the Modern-Era Retrospective Analysis for Research and Applications Aerosol Reanalysis data set. As aerosol optical depth increased, rainfall amounts from deep convective clouds increased at first and then decreased. The descending part of the trend is likely due to the aerosol radiative effect. Downwelling solar radiative fluxes at the surface decreased as aerosol optical depth increased. The decrease in solar radiation led to a decrease in ground heat fluxes and convective available potential energy, which is unfavorable for development of convective clouds and precipitation. The tendencies for lower cloud top temperatures, lower cloud top pressures, and higher cloud optical depths as a response to larger aerosol optical depths suggest the invigoration effect. Vertical velocity, relative humidity, and air temperature from the National Centers for Environmental Prediction Climate Forecast System Reanalysis were sorted to help investigate if the trends are dependent on any environmental conditions. How dynamic and microphysical factors strengthen or mitigate the impact of aerosols on clouds and precipitation and more details about their interplay should be studied further using more observations and model simulations.

  18. Direct Simulation Monte Carlo exploration of charge effects on aerosol evolution

    Science.gov (United States)

    Palsmeier, John F.

    Aerosols are potentially generated both during normal operations in a gas cooled Generation IV nuclear reactor and in all nuclear reactors during accident scenarios. These aerosols can become charged due to aerosol generation processes, radioactive decay of associated fission products, and ionizing atmospheres. Thus the role of charge on aerosol evolution, and hence on the nuclear source term, has been an issue of interest. There is a need for both measurements and modeling to quantify this role as these effects are not currently accounted for in nuclear reactor modeling and simulation codes. In this study the role of charge effects on the evolution of a spatially homogenous aerosol was explored via the application of the Direct Simulation Monte Carlo (DSMC) technique. The primary mechanisms explored were those of coagulation and electrostatic dispersion. This technique was first benchmarked by comparing the results obtained from both monodisperse and polydisperse DSMC evolution of charged aerosols with the results obtained by respectively deterministic and sectional techniques. This was followed by simulation of several polydisperse charged aerosols. Additional comparisons were made between the evolutions of charged and uncharged aerosols. The results obtained using DSMC in simple cases were comparable to those obtained from other techniques, without the limitations associated with more complex cases. Multicomponent aerosols of different component densities were also evaluated to determine the charge effects on their evolution. Charge effects can be significant and further explorations are warranted.

  19. Size measurement of radioactive aerosol particles in intense radiation fields using wire screens and imaging plates

    Energy Technology Data Exchange (ETDEWEB)

    Oki, Yuichi; Tanaka, Toru; Takamiya, Koichi; Ishi, Yoshihiro; UesugI, Tomonori; Kuriyama, Yasutoshi; Sakamoto, Masaaki; Ohtsuki, Tsutomu [Kyoto University Research Reactor Institute, Osaka (Japan); Nitta, Shinnosuke [Graduate School of Engineering, Kyoto University, Kyoto (Japan); Osada, Naoyuki [Advanced Science Research Center, Okayama University, Okayama (Japan)

    2016-09-15

    Very fine radiation-induced aerosol particles are produced in intense radiation fields, such as high-intensity accelerator rooms and containment vessels such as those in the Fukushima Daiichi nuclear power plant (FDNPP). Size measurement of the aerosol particles is very important for understanding the behavior of radioactive aerosols released in the FDNPP accident and radiation safety in high-energy accelerators. A combined technique using wire screens and imaging plates was developed for size measurement of fine radioactive aerosol particles smaller than 100 nm in diameter. This technique was applied to the radiation field of a proton accelerator room, in which radioactive atoms produced in air during machine operation are incorporated into radiation-induced aerosol particles. The size of 11C-bearing aerosol particles was analyzed using the wire screen technique in distinction from other positron emitters in combination with a radioactive decay analysis. The size distribution for 11C-bearing aerosol particles was found to be ca. 70 μm in geometric mean diameter. The size was similar to that for 7Be-bearing particles obtained by a Ge detector measurement, and was slightly larger than the number-based size distribution measured with a scanning mobility particle sizer. The particle size measuring method using wire screens and imaging plates was successfully applied to the fine aerosol particles produced in an intense radiation field of a proton accelerator. This technique is applicable to size measurement of radioactive aerosol particles produced in the intense radiation fields of radiation facilities.

  20. Notícia d’una mística catalana de principi del segle XVIII: Teresa Mir i March i la seva autobiografia espiritual Rahó de l’esperit.

    Directory of Open Access Journals (Sweden)

    Anna Garcia Busquets

    2013-06-01

    Full Text Available Resum: En aquest article es presenta l’autobiografia espiritual en català Rahó de l’esperit (1709-1714 de la mística d’Olot Teresa Mir i March (1681-1764 i la Relació introductòria del seu pare espiritual, Esteve Gay, conservades en un testimoni únic, el manuscrit número 6 de la Biblioteca de Reserva de la Universitat de Barcelona. Se’n detalla l’estat de la qu?estió, la descripció i estructura del còdex, així com una anàlisi sumària dels diferents elements que el componen. S’aprofundeix en les dades biogràfiques de la beata a partir de la recerca arxivística. Es detallen les lectures de Mir durant els anys de redacció de Rahó de l’esperit (devocionaris i tractats espirituals, i es fa esment de com, a vegades, les representacions pictòriques i la imatgeria que tenia al seu abast l’ajudaven a formar les visions amb el seu poder evocador.Paraules clau: Estudis de gènere, Literatura catalana moderna, Autobiografia, MísticaAbstract: The article presents the spiritual autobiography in Catalan Rahó de l’esperit (1709-1714 by Teresa Mir i March (1681-1764, the mystic from Olot, and the introductory panegyric text by Esteve Gay, her spiritual father. The source is the unique documented testimonial: the manuscript number 6, Rare Book and Manuscript Library of the University of Barcelona. Further details on the issue are a description and the codex structure as well as a summary analysis of its different elements and a further learning of the blessed young lady‘s biography through archive research. A listing of Mir’s readings at the time Rahó de l’esperit (prayer books and spiritual treatises was written and details of how sometimes the powerful evocative pictorial representations and imagery she had access to, helped her conform her visions.Keywords: Gender studies, Modern Catalan literature, Autobiography, Mysticism

  1. International Cooperative for Aerosol Prediction Workshop on Aerosol Forecast Verification

    Science.gov (United States)

    Benedetti, Angela; Reid, Jeffrey S.; Colarco, Peter R.

    2011-01-01

    The purpose of this workshop was to reinforce the working partnership between centers who are actively involved in global aerosol forecasting, and to discuss issues related to forecast verification. Participants included representatives from operational centers with global aerosol forecasting requirements, a panel of experts on Numerical Weather Prediction and Air Quality forecast verification, data providers, and several observers from the research community. The presentations centered on a review of current NWP and AQ practices with subsequent discussion focused on the challenges in defining appropriate verification measures for the next generation of aerosol forecast systems.

  2. Could aerosol emissions be used for regional heat wave mitigation?

    Directory of Open Access Journals (Sweden)

    D. N. Bernstein

    2013-07-01

    Full Text Available Geoengineering applications by injection of sulfate aerosols into the stratosphere are under consideration as a measure of last resort to counter global warming. Here a potential regional-scale application to offset the impacts of heat waves is critically examined. Using the Weather Research and Forecasting model with fully coupled chemistry (WRF-Chem, the effect of regional-scale sulfate aerosol emission over California in each of two days of the July 2006 heat wave is used to quantify potential reductions in surface temperature as a function of emission rates in a layer at 12 km altitude. Local meteorological factors yield geographical differences in surface air temperature sensitivity. For emission rates of approximately 30 μg m−2 s−1 of sulfate aerosols (with standard WRF-Chem size distribution over the region, temperature decreases of around 7 °C result during the middle part of the day over the Central Valley, one of the areas hardest hit by the heat wave. Regions more ventilated with oceanic air such as Los Angeles have slightly smaller reductions. The length of the hottest part of the day is also reduced. Advection effects on the aerosol cloud must be more carefully forecast for smaller injection regions. Verification of the impacts could be done via measurements of differences in reflected and surface downward shortwave. Such regional geoengineering applications with specific near-term target effects but smaller cost and side effects could potentially provide a means of testing larger scale applications. However, design considerations for regional applications, such as a preference for injection at a level of relatively low wind speed, differ from those for global applications. The size of the required injections and the necessity of injection close to the target region raise substantial concerns. The evaluation of this regional-scale application is thus consistent with global model evaluations, emphasizing that mitigation via

  3. 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.

  4. 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.

  5. Aerosol measurement program strategy for global aerosol backscatter model development

    Science.gov (United States)

    Bowdle, David A.

    1985-01-01

    The purpose was to propose a balanced program of aerosol backscatter research leading to the development of a global model of aerosol backscatter. Such a model is needed for feasibility studies and systems simulation studies for NASA's prospective satellite-based Doppler lidar wind measurement system. Systems of this kind measure the Doppler shift in the backscatter return from small atmospheric aerosol wind tracers (of order 1 micrometer diameter). The accuracy of the derived local wind estimates and the degree of global wind coverage for such a system are limited by the local availability and by the global scale distribution of natural aerosol particles. The discussions here refer primarily to backscatter model requirements at CO2 wavelengths, which have been selected for most of the Doppler lidar systems studies to date. Model requirements for other potential wavelengths would be similar.

  6. The Dynamics of Aerosols in Condensational Scrubbers

    DEFF Research Database (Denmark)

    Johannessen, Jens Tue; Christensen, Jan A.; Simonsen, Ole;

    1997-01-01

    A mathematical model for the simulation of the dynamics of aerosol change in condensational scrubbers and scrubbing condensers is proposed. The model is applicable for packed column gas/liquid contact when plug flow can be assumed. The model is compared with experimental data for particle removal...... in a pilot plant condensational scrubber. The model can satisfactorily predict particle growth and particle deposition by diffusional, convective and inertial mechanisms for a wide range of conditions. The parameters of principal importance for the model precision are identified and a procedure...

  7. Determination of Marine Aerosol Properties Using a Bistatic Nephelometer

    Science.gov (United States)

    2016-06-07

    effective polarimetric strategy to improve visibility and target discrimination . Measurements of scattering in the MABL, particularly in the coastal...refined, greater insights into the nature of the contents of the marine atmosphere should be achieved. IMPACTS/APPLICATIONS Because the marine...will establish the significance of the nature of the aerosols to visibility and image enhancement. TRANSITIONS Scanning polarization-modulation

  8. AMARSI: Aerosol modeling and retrieval from multi-spectral imagers

    NARCIS (Netherlands)

    Leeuw, G. de; Curier, R.L.; Staroverova, A.; Kokhanovsky, A.; Hoyningen-Huene, W. van; Rozanov, V.V.; Burrows, J.P.; Hesselmans, G.; Gale, L.; Bouvet, M.

    2008-01-01

    The AMARSI project aims at the development and validation of aerosol retrieval algorithms over ocean. One algorithm will be developed for application with data from the Multi Spectral Imager (MSI) on EarthCARE. A second algorithm will be developed using the combined information from AATSR and MERIS,

  9. Laboratory Testing of Aerosol for Enclosure Air Sealing

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, Curtis [Building Industry Research Alliance (BIRA), Stockton, CA (United States); Modera, Mark [Building Industry Research Alliance (BIRA), Stockton, CA (United States)

    2012-05-01

    This report presents a process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

  10. The NASA Decadal Survey Aerosol, Cloud, Ecosystems Mission

    Science.gov (United States)

    McClain, Charles R.; Bontempi, Paula; Maring, Hal

    2011-01-01

    In 2007, the National Academy of Sciences delivered a Decadal Survey (Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond) for NASA, NOAA, and USGS, which is a prioritization of future satellite Earth observations. The recommendations included 15 missions (13 for NASA, two for NOAA), which were prioritized into three groups or tiers. One of the second tier missions is the Aerosol, Cloud, (ocean) Ecosystems (ACE) mission, which focuses on climate forcing, cloud and aerosol properties and interactions, and ocean ecology, carbon cycle science, and fluxes. The baseline instruments recommended for ACE are a cloud radar, an aerosol/cloud lidar, an aerosol/cloud polarimeter, and an ocean radiometer. The instrumental heritage for these measurements are derived from the Cloudsat, CALIPSO, Glory, SeaWiFS and Aqua (MODIS) missions. In 2008, NASA HQ, lead by Hal Maring and Paula Bontempi, organized an interdisciplinary science working group to help formulate the ACE mission by refining the science objectives and approaches, identifying measurement (satellite and field) and mission (e.g., orbit, data processing) requirements, technology requirements, and mission costs. Originally, the disciplines included the cloud, aerosol, and ocean biogeochemistry communities. Subsequently, an ocean-aerosol interaction science working group was formed to ensure the mission addresses the broadest range of science questions possible given the baseline measurements, The ACE mission is a unique opportunity for ocean scientists to work closely with the aerosol and cloud communities. The science working groups are collaborating on science objectives and are defining joint field studies and modeling activities. The presentation will outline the present status of the ACE mission, the science questions each discipline has defined, the measurement requirements identified to date, the current ACE schedule, and future opportunities for broader community

  11. Using Satellite Aerosol Retrievals to Monitor Surface Particulate Air Quality

    Science.gov (United States)

    Levy, Robert C.; Remer, Lorraine A.; Kahn, Ralph A.; Chu, D. Allen; Mattoo, Shana; Holben, Brent N.; Schafer, Joel S.

    2011-01-01

    The MODIS and MISR aerosol products were designed nearly two decades ago for the purpose of climate applications. Since launch of Terra in 1999, these two sensors have provided global, quantitative information about column-integrated aerosol properties, including aerosol optical depth (AOD) and relative aerosol type parameters (such as Angstrom exponent). Although primarily designed for climate, the air quality (AQ) community quickly recognized that passive satellite products could be used for particulate air quality monitoring and forecasting. However, AOD and particulate matter (PM) concentrations have different units, and represent aerosol conditions in different layers of the atmosphere. Also, due to low visible contrast over brighter surface conditions, satellite-derived aerosol retrievals tend to have larger uncertainty in urban or populated regions. Nonetheless, the AQ community has made significant progress in relating column-integrated AOD at ambient relative humidity (RH) to surface PM concentrations at dried RH. Knowledge of aerosol optical and microphysical properties, ambient meteorological conditions, and especially vertical profile, are critical for physically relating AOD and PM. To make urban-scale maps of PM, we also must account for spatial variability. Since surface PM may vary on a finer spatial scale than the resolution of standard MODIS (10 km) and MISR (17km) products, we test higher-resolution versions of MODIS (3km) and MISR (1km research mode) retrievals. The recent (July 2011) DISCOVER-AQ campaign in the mid-Atlantic offers a comprehensive network of sun photometers (DRAGON) and other data that we use for validating the higher resolution satellite data. In the future, we expect that the wealth of aircraft and ground-based measurements, collected during DISCOVER-AQ, will help us quantitatively link remote sensed and ground-based measurements in the urban region.

  12. Deposition of graphene nanomaterial aerosols in human upper airways.

    Science.gov (United States)

    Su, Wei-Chung; Ku, Bon Ki; Kulkarni, Pramod; Cheng, Yung Sung

    2016-01-01

    Graphene nanomaterials have attracted wide attention in recent years on their application to state-of-the-art technology due to their outstanding physical properties. On the other hand, the nanotoxicity of graphene materials also has rapidly become a serious concern especially in occupational health. Graphene naomaterials inevitably could become airborne in the workplace during manufacturing processes. The inhalation and subsequent deposition of graphene nanomaterial aerosols in the human respiratory tract could potentially result in adverse health effects to exposed workers. Therefore, investigating the deposition of graphene nanomaterial aerosols in the human airways is an indispensable component of an integral approach to graphene occupational health. For this reason, this study carried out a series of airway replica deposition experiments to obtain original experimental data for graphene aerosol airway deposition. In this study, graphene aerosols were generated, size classified, and delivered into human airway replicas (nasal and oral-to-lung airways). The deposition fraction and deposition efficiency of graphene aerosol in the airway replicas were obtained by a novel experimental approach. The experimental results acquired showed that the fractional deposition of graphene aerosols in airway sections studied were all less than 4%, and the deposition efficiency in each airway section was generally lower than 0.03. These results indicate that the majority of the graphene nanomaterial aerosols inhaled into the human respiratory tract could easily penetrate through the head airways as well as the upper part of the tracheobronchial airways and then transit down to the lower lung airways, where undesired biological responses might be induced.

  13. Stratospheric aerosol geoengineering

    Science.gov (United States)

    Robock, Alan

    2015-03-01

    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.

  14. 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.

  15. Stratospheric aerosol geoengineering

    Energy Technology Data Exchange (ETDEWEB)

    Robock, Alan [Department of Environmental Sciences, Rutgers University, 14 College Farm Road, New Brunswick, NJ 08901 (United States)

    2015-03-30

    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.

  16. Espécies de cigarrinhas em cultivo de café no Município de Santa Teresa, Espírito Santo, Brasil (Hemiptera, Cicadellidae, Cicadellinae

    Directory of Open Access Journals (Sweden)

    Rachel A. Carvalho

    2015-01-01

    Full Text Available As cigarrinhas da subfamília Cicadellinae são importantes vetores de patógenos de plantas cultivadas, dentre eles, a bactéria Xylella fastidiosa, que, no Brasil, ataca cultivos de citros, café e também de ameixa. Pouca informação é conhecida sobre a ocorrência, distribuição e biologia de cicadelíneos em plantações de café. Este trabalho apresenta uma lista de 141 espécimes, coletados em meses alternados, no período entre junho de 2009 e abril de 2010, em plantação de café no Município de Santa Teresa no Estado do Espírito Santo, Brasil. Esses espécimes estão distribuídos em 16 gêneros e 21 espécies pertencentes às duas tribos de Cicadellinae: Cicadellini e Proconiini. Dentre os Cicadellini listados, o gênero Graphocephala é, pela primeira vez, registrado para o Brasil.

  17. La recuperació de la tradició femenina de la novel·la policíaca clàssica en l'obra criminal de Teresa Solana

    Directory of Open Access Journals (Sweden)

    Stewart King

    2015-10-01

    Full Text Available Aquest article explora la recuperació de la tradició femenina de la novel·la policíaca clàssica en tres novel·les criminals de l'autora catalana Teresa Solana: Un crim imperfecte (2006, Drecera al paradís (2007 i L'hora zen. Un crim refinat (2011. En prendre com a punt de partida la reinterpretació de l'obra de Christie, Sayers i altres escriptores de la novel·la policíaca clàssica que les crítiques feministes han portat a terme els últims anys, l'article manté que Solana recupera i reivindica la tradició femenina per fer una crítica política i cultural de la societat barcelonina contemporània. A més a més, l'obra de Solana fa possible una nova lectura i una nova apreciació d’aquest subgènere tradicionalment menyspreat pels escriptors i crítics masculins.

  18. Do atmospheric aerosols form glasses?

    OpenAIRE

    Zobrist, B.; Marcolli, C.; Pedernera, D. A.; Koop, T.

    2008-01-01

    A new process is presented by which water soluble organics might influence ice nucleation, ice growth, chemical reactions and water uptake of aerosols in the upper troposphere: the formation of glassy aerosol particles. Glasses are disordered amorphous (non-crystalline) solids that form when a liquid is cooled without crystallization until the viscosity increases exponentially and molecular diffusion practically ceases. The glass transition temperatures, Tg

  19. Retrievals of Effective Aerosol Layer Height and Single Scattering Albedo for Biomass-Burning Smoke and Mineral Dust Aerosols from A-Train Observations

    Science.gov (United States)

    Jeong, M.; Hsu, C.

    2010-12-01

    Launches of state-of-the-art satellite sensors dedicated to aerosol remote sensing in recent years marked the beginning of a new era in aerosol-related studies by virtue of the well-coordinated observing system consisting of an array of satellites flown in formation, so called A-Train (Afternoon satellites constellation). The capabilities of the individual sensors aboard the A-Train satellites are complementary and overlapping in terms of retrievable aerosol parameters, sensitivity, spatial resolution and coverage. Thus, there is a great potential to gain value-added information about aerosols by merging observations from the A-Train sensors. In this study, we introduce a new algorithm, which can be utilized to derive aerosol layer height (ALH) and single scattering albedo (SSA) for biomass-burning smoke and airborne mineral dust aerosols by synthesizing observations from three A-Train satellite sensors: CALIOP, MODIS, and OMI. By using this algorithm, it is presented that ALH and SSA of biomass-burning smoke aerosols over North America, Southeast Asia, and Europe can be derived successfully. We show the retrieved values of SSA bear reasonable agreements with those from AERONET. The results of this study also reveal that the algorithm has a basic skill to estimate ALH by combining only MODIS and OMI observations, allowing us to separate smoke aerosols residing within the boundary layer from those elevated in the free troposphere. Currently, another version of the algorithm to be applicable for mineral dust aerosols is under development, and earlier results will be presented. Results from this study are expected to provide a better understanding of transport and radiative effects of biomass-burning smoke and mineral dust aerosols.

  20. Atmospheric aerosol layers over Bangkok Metropolitan Region from CALIPSO observations

    Science.gov (United States)

    Bridhikitti, Arika

    2013-06-01

    Previous studies suggested that aerosol optical depth (AOD) from the Earth Observing System satellite retrievals could be used for inference of ground-level air quality in various locations. This application may be appropriate if pollution in elevated atmospheric layers is insignificant. This study investigated the significance of elevated air pollution layers over the Bangkok Metropolitan Region (BMR) from all available aerosol layer scenes taken from Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) for years 2007 to 2011. The results show that biomass burning smoke layers alone were the most frequently observed. The smoke layers accounted for high AOD variations and increased AOD levels. In the dry seasons, the smoke layers alone with high AOD levels were likely brought to the BMR via northeasterly to easterly prevailing winds and found at altitudes above the typical BMR mixing heights of approximately 0.7 to 1.5 km. The smoke should be attributed to biomass burning emissions outside the BMR.

  1. Modeling of Aerosol Vertical Profiles Using GIS and Remote Sensing

    Directory of Open Access Journals (Sweden)

    Kwon Ho Lee

    2009-06-01

    Full Text Available The use of Geographic Information Systems (GIS and Remote Sensing (RS by climatologists, environmentalists and urban planners for three dimensional modeling and visualization of the landscape is well established. However no previous study has implemented these techniques for 3D modeling of atmospheric aerosols because air quality data is traditionally measured at ground points, or from satellite images, with no vertical dimension. This study presents a prototype for modeling and visualizing aerosol vertical profiles over a 3D urban landscape in Hong Kong. The method uses a newly developed technique for the derivation of aerosol vertical profiles from AERONET sunphotometer measurements and surface visibility data, and links these to a 3D urban model. This permits automated modeling and visualization of aerosol concentrations at different atmospheric levels over the urban landscape in near-real time. Since the GIS platform permits presentation of the aerosol vertical distribution in 3D, it can be related to the built environment of the city. Examples are given of the applications of the model, including diagnosis of the relative contribution of vehicle emissions to pollution levels in the city, based on increased near-surface concentrations around weekday rush-hour times. The ability to model changes in air quality and visibility from ground level to the top of tall buildings is also demonstrated, and this has implications for energy use and environmental policies for the tall mega-cities of the future.

  2. Synthesis of nanosized metal particles from an aerosol

    Directory of Open Access Journals (Sweden)

    Srećko R. Stopić

    2013-10-01

    Full Text Available The synthesis of metallic nanoparticles from the precursor solution of salts using the ultrasonic spray pyrolysis method was considered in this work. During the control of process parameters (surface tension and density, the concentration of solution, residence time of aerosol in the reactor, presence of additives, gas flow rate, decomposition temperature of aerosol, type of precursor and working atmosphere it is possible to guide the process in order to obtain powders with such a morphology which satisfies more complex requirements for the desired properties of advanced engineering materials.  Significant advance in the improvement of powder characteristics (lower particles sizes, better spheroidity, higher surface area was obtained by the application of the ultrasonic generator for the preparation of aerosols. Ultrasonic spray pyrolysis is performed by the action of a powerful source of ultrasound on the corresponding precursor solution forming the aerosol with a constant droplet size, which depends on the characteristics of liquid and the frequency of ultrasound. The produced aerosols were transported into the hot reactor, which enables the reaction to occur in a very small volume of a particle and formation of  nanosized powder. Spherical, nanosized particles of metals (Cu, Ag, Au, Co were produced with new and improved physical and chemical characteristics at the IME, RWTH Aachen University. The high costs associated with small quantities of produced nanosized particles represent a limitation of the USP-method. Therefore, scale up of the ultrasonic spray pyrolysis was performed as a final target in the synthesis of nanosized powder.

  3. Cloud-Aerosol-Radiation (CAR ensemble modeling system

    Directory of Open Access Journals (Sweden)

    X.-Z. Liang

    2013-04-01

    Full Text Available A Cloud-Aerosol-Radiation (CAR ensemble modeling system has been developed to incorporate the largest choices of alternative parameterizations for cloud properties (cover, water, radius, optics, geometry, aerosol properties (type, profile, optics, radiation transfers (solar, infrared, and their interactions. These schemes form the most comprehensive collection currently available in the literature, including those used by the world leading general circulation models (GCMs. The CAR provides a unique framework to determine (via intercomparison across all schemes, reduce (via optimized ensemble simulations, and attribute specific key factors for (via physical process sensitivity analyses the model discrepancies and uncertainties in representing greenhouse gas, aerosol and cloud radiative forcing effects. This study presents a general description of the CAR system and illustrates its capabilities for climate modeling applications, especially in the context of estimating climate sensitivity and uncertainty range caused by cloud-aerosol-radiation interactions. For demonstration purpose, the evaluation is based on several CAR standalone and coupled climate model experiments, each comparing a limited subset of the full system ensemble with up to 896 members. It is shown that the quantification of radiative forcings and climate impacts strongly depends on the choices of the cloud, aerosol and radiation schemes. The prevailing schemes used in current GCMs are likely insufficient in variety and physically biased in a significant way. There exists large room for improvement by optimally combining radiation transfer with cloud property schemes.

  4. Satellite-Derived Aerosol Climate Data Records in the ESA Aerosol_Cci Project: From ERS-2, Envisat to Sentinel-3

    Science.gov (United States)

    de Leeuw, Gerrit; Holzer-Popp, Thomas; North, Peter R. J.; Heckel, Andreas; Pinnock, Simon

    2015-12-01

    With the focus of Sentinel-3 on ocean applications and services, important parts of the payload are the Sea and Land Surface Temperature Radiometer (SLSTR) and the Ocean Land Colour Instrument (OLCI). Apart from Ocean applications, these instruments are also very important for atmospheric observations and in particular for aerosol retrieval. This is the reason why the predecessor instruments AATSR and MERIS have extensively been used in the ESA Climate Change Initiative project Aerosol_cci. In this contribution a brief overview of the current status of the Aerosol_cci project is presented. Full-mission time series of ATSR-2 and AATSR have been processed to provide 17 years of global aerosol information. Selected examples of recent achievements are presented. The experience with ATSR-2, AATSR and MERIS will be used to continue the current time series with SLSTR and OLCI.

  5. CALIPSO Observations of Aerosol Properties Near Clouds

    Science.gov (United States)

    Marshak, Alexander; Varnai, Tamas; Yang, Weidong

    2010-01-01

    Clouds are surrounded by a transition zone of rapidly changing aerosol properties. Characterizing this zone is important for better understanding aerosol-cloud interactions and aerosol radiative effects as well as for improving satellite measurements of aerosol properties. We present a statistical analysis of a global dataset of CALIPSO (Cloud-Aerosol Lidar and infrared Pathfinder Satellite Observation) Lidar observations over oceans. The results show that the transition zone extends as far as 15 km away from clouds and it is ubiquitous over all oceans. The use of only high confidence level cloud-aerosol discrimination (CAD) data confirms the findings. However, the results underline the need for caution to avoid biases in studies of satellite aerosol products, aerosol-cloud interactions, and aerosol direct radiative effects.

  6. 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.

  7. The Multi-Dimensional Challenge of Validating Remote-Sensing Aerosol-Type Retrievals

    Science.gov (United States)

    Kahn, R. A.; Gaitley, B. J.; Limbacher, J.

    2014-12-01

    In addition to aerosol optical depth (AOD), aerosol type is required globally for climate-forcing calculations, constraining aerosol transport models, and other applications. However, validating satellite aerosol type retrievals is much more challenging than testing AOD results, because aerosol type is a more complex quantity, and ground-truth data are far less numerous and generally not as robust. We employ a combination of assessment relative to climatological expectation, statistical comparisons with surface-based observations, and near-coincident field campaign measurements, to evaluate MISR aerosol-type retrieval results. Although the retrievals are not constrained by a priori expectations, there is general regional coherence in the dominant retrieved aerosol types, indicating consistency in the retrieval process. Comparisons with expectation, on a regional, seasonal basis, demonstrate qualitative consistency with regard to particle size (three-to-five bins), shape (spherical vs. non-spherical), and single-scattering albedo (SSA; two-to-four bins) when mid-visible AOD exceeds about 0.15 or 0.2. Statistical comparisons with surface-based sun and sky-scanning photometer retrievals provide both qualitative and quantitative illustration of retrieval sensitivity, identifying strengths and limitations of the MISR Standard Version 22 aerosol product, and pointing to specific areas where improvements could be made. Field campaign results offer the most detailed and robust aerosol-type constraints. They allow us, with the help of the MISR Research aerosol retrieval algorithm, to test the limits of the MISR data information content, which in specific cases substantially exceeds the general sensitivity. This presentation will briefly review the statistical techniques employed and summarize the key MISR aerosol-type retrieval validation results of this work.

  8. Multi-sensor cloud and aerosol retrieval simulator and remote sensing from model parameters - Part 2: Aerosols

    Science.gov (United States)

    Wind, Galina; da Silva, Arlindo M.; Norris, Peter M.; Platnick, Steven; Mattoo, Shana; Levy, Robert C.

    2016-07-01

    operational remote-sensing algorithms.Specifically, the MCARS-computed radiances are input into the processing chain used to produce the MODIS Data Collection 6 aerosol product (M{O/Y}D04). The M{O/Y}D04 product is of course normally produced from M{O/Y}D021KM MODIS Level-1B radiance product directly acquired by the MODIS instrument. MCARS matches the format and metadata of a M{O/Y}D021KM product. The resulting MCARS output can be directly provided to MODAPS (MODIS Adaptive Processing System) as input to various operational atmospheric retrieval algorithms. Thus the operational algorithms can be tested directly without needing to make any software changes to accommodate an alternative input source.We show direct application of this synthetic product in analysis of the performance of the MOD04 operational algorithm. We use biomass-burning case studies over Amazonia employed in a recent Working Group on Numerical Experimentation (WGNE)-sponsored study of aerosol impacts on numerical weather prediction (Freitas et al., 2015). We demonstrate that a known low bias in retrieved MODIS aerosol optical depth appears to be due to a disconnect between actual column relative humidity and the value assumed by the MODIS aerosol product.

  9. Implementation of a Markov Chain Monte Carlo method to inorganic aerosol modeling of observations from the MCMA-2003 campaign – Part I: Model description and application to the La Merced site

    Directory of Open Access Journals (Sweden)

    F. M. San Martini

    2006-01-01

    Full Text Available The equilibrium inorganic aerosol model ISORROPIA was embedded in a Markov Chain Monte Carlo algorithm to develop a powerful tool to analyze aerosol data and predict gas phase concentrations where these are unavailable. The method directly incorporates measurement uncertainty, prior knowledge, and provides a formal framework to combine measurements of different quality. The method was applied to particle- and gas-phase precursor observations taken at La Merced during the Mexico City Metropolitan Area (MCMA 2003 Field Campaign and served to discriminate between diverging gas-phase observations of ammonia and predict gas-phase concentrations of hydrochloric acid. The model reproduced observations of particle-phase ammonium, nitrate, and sulfate well. The most likely concentrations of ammonia were found to vary between 4 and 26 ppbv, while the range for nitric acid was 0.1 to 55 ppbv. During periods where the aerosol chloride observations were consistently above the detection limit, the model was able to reproduce the aerosol chloride observations well and predicted the most likely gas-phase hydrochloric acid concentration varied between 0.4 and 5 ppbv. Despite the high ammonia concentrations observed and predicted by the model, when the aerosols were assumed to be in the efflorescence branch they are predicted to be acidic (pH~3.

  10. Stratospheric aerosol acidity, density, and refractive index deduced from SAGE 2 and NMC temperature data

    Science.gov (United States)

    Yue, G. K.; Poole, L. R.; Wang, P.-H.; Chiou, E. W.

    1994-01-01

    Water vapor concentrations obtained by the Stratospheric Aerosol and Gas Experiment 2 (SAGE 2) and collocated temperatures provided by the National Meteorological Center (NMC) from 1986 to 1990 are used to deduce seasonally and zonally averaged acidity, density, and refractive index of stratospheric aerosols. It is found that the weight percentage of sulfuric acid in the aerosols increases from about 60 just above the tropopause to about 86 at 35 km. The density increases from about 1.55 to 1.85 g/cu cm between the same altitude limits. Some seasonal variations of composition and density are evident at high latitudes. The refractive indices at 1.02, 0.694, and 0.532 micrometers increase, respectively, from about 1.425, 1.430, and 1.435 just above the tropopause to about 1.445, 1.455, and 1.458 at altitudes above 27 km, depending on the season and latitude. The aerosol properties presented can be used in models to study the effectiveness of heterogeneous chemistry, the mass loading of stratospheric aerosols, and the extinction and backscatter of aerosols at different wavelengths. Computed aerosol surface areas, rate coefficients for the heterogeneous reaction ClONO2 + H2O yields HOCl + HNO3 and aerosol mass concentrations before and after the Pinatubo eruption in June 1991 are shown as sample applications.

  11. Air detoxification with nanosize TiO2 aerosol tested on mice.

    Science.gov (United States)

    Besov, A S; Krivova, N A; Vorontsov, A V; Zaeva, O B; Kozlov, D V; Vorozhtsov, A B; Parmon, V N; Sakovich, G V; Komarov, V F; Smirniotis, P G; Eisenreich, N

    2010-01-15

    A method for fast air purification using high concentration aerosol of TiO(2) nanoparticles is evaluated in a model chemical catastrophe involving toxic vapors of diisopropyl fluorophosphate (DFP). Mice are used as human model in a closed 100 dm(3) chamber. Exposure of mice to 37 ppm of DFP vapor for 15 min resulted in acute poisoning. Spraying TiO(2) aerosol in 2 min after the start of exposure to DFP vapors resulted in quick removal of DFP vapors from the chamber's air. Animals did not show signs of poisoning after the decontamination experiment and exposure to TiO(2) aerosol alone. Reactive oxygen species (ROS) and antioxidant activity (AOA) of mice blood plasma were measured for animals exposed to sound of aerosol generator, DFP vapors, TiO(2) aerosol and DFP vapors+TiO(2) aerosol. Reduced ROS and increased AOA were found for mice exposure to sound, DFP and TiO(2) aerosol. Exposure to DFP and decontamination with TiO(2) nanoparticles resulted in decreased AOA in 48 h following the exposure. The results suggest that application of TiO(2) aerosol is a powerful method of air purification from toxic hydrolysable compounds with moderate health aftermaths and requires further study and optimization.

  12. Evaluation of synergized pyrethrin aerosol for control of Tribolium castaneum and Tribolium confusum (Coleoptera: Tenebrionidae).

    Science.gov (United States)

    Kharel, Kabita; Arthur, Frank H; Zhu, Kun Yan; Campbell, James F; Subramanyam, Bhadriraju

    2014-02-01

    Aerosol insecticides are being used in flour mill pest management programs, but there is limited information on their efficacy on different insect life stages. In this study, we evaluated the efficacy of synergized pyrethrin applied as an aerosol against eggs, larvae, pupae, and adults of the red flour beetle, Tribolium castaneum (Herbst), and the confused flour beetle, Tribolium confusum Jacquelin du Val. Effects of direct and indirect exposure were evaluated by exposing each life stage to the aerosol and then transferring to untreated flour, transferring untreated insects to treated flour, or exposing both the insects and the flour to the aerosol. The aerosol produced >88% mortality of both species and all life stages when insects were directly treated and transferred to either treated or untreated flour. Mortality was significantly reduced when insects were either treated together with flour or untreated insects were transferred to treated flour (indirect exposure to the aerosol). Larvae and adults of both species were more tolerant compared with eggs and pupae. Recovery of moribund adults in the indirect exposure treatments was greater compared with recovery of moribund insects in the direct exposure treatments. Good sanitation before aerosol application could facilitate direct exposure of insects and thus increase aerosol efficacy inside flour mills.

  13. Study of Aerosol Chemical Composition Based on Aerosol Optical Properties

    Science.gov (United States)

    Berry, Austin; Aryal, Rudra

    2015-03-01

    We investigated the variation of aerosol absorption optical properties obtained from the CIMEL Sun-Photometer measurements over three years (2012-2014) at three AERONET sites GSFC; MD Science_Center and Tudor Hill, Bermuda. These sites were chosen based on the availability of data and locations that can receive different types of aerosols from land and ocean. These absorption properties, mainly the aerosol absorption angstrom exponent, were analyzed to examine the corresponding aerosol chemical composition. We observed that the retrieved absorption angstrom exponents over the two sites, GSFC and MD Science Center, are near 1 (the theoretical value for black carbon) and with low single scattering albedo values during summer seasons indicating presence of black carbon. Strong variability of aerosol absorption properties were observed over Tudor Hill and will be analyzed based on the air mass embedded from ocean side and land side. We will also present the seasonal variability of these properties based on long-range air mass sources at these three sites. Brent Holben, NASA GSFC, AERONET, Jon Rodriguez.

  14. Photochemical processing of organic aerosol at nearby continental sites: contrast between urban plumes and regional aerosol

    Directory of Open Access Journals (Sweden)

    J. G. Slowik

    2010-10-01

    Full Text Available As part of the BAQS-Met 2007 field campaign, Aerodyne time-of-flight aerosol mass spectrometers (ToF-AMS were deployed at two sites in southwestern Ontario from 17 June to 11 July, 2007. One instrument was located at Harrow, ON, a rural, agriculture-dominated area approximately 40 km southeast of the Detroit/Windsor/Windsor urban area and 5 km north of Lake Erie. The second instrument was located at Bear Creek, ON, a rural site approximately 70 km northeast of the Harrow site and 50 km east of Detroit/Windsor. Positive matrix factorization analysis of the combined organic mass spectral dataset yields factors related to secondary organic aerosol (SOA, direct emissions, and uptake processes. This is the first application of PMF to simultaneous AMS measurements at different sites, an approach which allows for self-consistent, direct comparison of the datasets. Case studies are utilized to investigate processing of SOA from (1 fresh emissions from Detroit/Windsor and (2 regional aerosol during periods of inter-site flow. A strong correlation is observed between SOA/excess CO and photochemical age as represented by the NOx/NOy ratio for Detroit/Windsor outflow. Although this correlation is not evident for more aged air, measurements at the two sites during inter-site transport nevertheless show evidence of continued atmospheric processing by SOA production.

  15. Global simulations of aerosol processing in clouds

    Directory of Open Access Journals (Sweden)

    C. Hoose

    2008-12-01

    Full Text Available An explicit and detailed representation of in-droplet and in-crystal aerosol particles in stratiform clouds has been introduced in the global aerosol-climate model ECHAM5-HAM. The new scheme allows an evaluation of the cloud cycling of aerosols and an estimation of the relative contributions of nucleation and collision scavenging, as opposed to evaporation of hydrometeors in the global aerosol processing by clouds. On average an aerosol particle is cycled through stratiform clouds 0.5 times. The new scheme leads to important changes in the simulated fraction of aerosol scavenged in clouds, and consequently in the aerosol wet deposition. In general, less aerosol is scavenged into clouds with the new prognostic treatment than what is prescribed in standard ECHAM5-HAM. Aerosol concentrations, size distributions, scavenged fractions and cloud droplet concentrations are evaluated and compared to different observations. While the scavenged fraction and the aerosol number concentrations in the marine boundary layer are well represented in the new model, aerosol optical thickness, cloud droplet number concentrations in the marine boundary layer and the aerosol volume in the accumulation and coarse modes over the oceans are overestimated. Sensitivity studies suggest that a better representation of below-cloud scavenging, higher in-cloud collision coefficients, or a reduced water uptake by seasalt aerosols could reduce these biases.

  16. Global simulations of aerosol processing in clouds

    Directory of Open Access Journals (Sweden)

    C. Hoose

    2008-07-01

    Full Text Available An explicit and detailed representation of in-droplet and in-crystal aerosol particles in stratiform clouds has been introduced in the global aerosol-climate model ECHAM5-HAM. The new scheme allows an evaluation of the cloud cycling of aerosols and an estimation of the relative contributions of nucleation and collision scavenging, as opposed to evaporation of hydrometeors in the global aerosol processing by clouds. On average an aerosol particle is cycled through stratiform clouds 0.5 times. The new scheme leads to important changes in the simulated fraction of aerosol scavenged in clouds, and consequently in the aerosol wet deposition. In general, less aerosol is scavenged into clouds with the new prognostic treatment than what is prescribed in standard ECHAM5-HAM. Aerosol concentrations, size distributions, scavenged fractions and cloud droplet concentrations are evaluated and compared to different observations. While the scavenged fraction and the aerosol number concentrations in the marine boundary layer are well represented in the new model, aerosol optical thickness, cloud droplet number concentrations in the marine boundary layer and the aerosol volume in the accumulation and coarse modes over the oceans are overestimated. Sensitivity studies suggest that a better representation of below-cloud scavenging, higher in-cloud collision coefficients, or a reduced water uptake by seasalt aerosols could reduce these biases.

  17. Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the UK

    Science.gov (United States)

    McMeeking, G. R.; Morgan, W. T.; Flynn, M.; Highwood, E. J.; Turnbull, K.; Haywood, J.; Coe, H.

    2011-05-01

    Black carbon (BC) aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2) measurements of refractory BC (rBC) mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the UK. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA) operated by the Facility for Airborne Atmospheric Measurements (FAAM). We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS) and used positive matrix factorization to separate hydrocarbon-like (HOA) and oxygenated organic aerosols (OOA). We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx) ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA) did change for different air masses, with lower SSA observed in

  18. Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the United Kingdom

    Science.gov (United States)

    McMeeking, G. R.; Morgan, W. T.; Flynn, M.; Highwood, E. J.; Turnbull, K.; Haywood, J.; Coe, H.

    2011-09-01

    Black carbon (BC) aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2) measurements of refractory BC (rBC) mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the United Kingdom. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA) operated by the Facility for Airborne Atmospheric Measurements (FAAM). We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS) and used positive matrix factorization to separate hydrocarbon-like (HOA) and oxygenated organic aerosols (OOA). We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx) ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA) did change for different air masses, with lower SSA

  19. Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the United Kingdom

    Directory of Open Access Journals (Sweden)

    G. R. McMeeking

    2011-09-01

    Full Text Available Black carbon (BC aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2 measurements of refractory BC (rBC mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the United Kingdom. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA operated by the Facility for Airborne Atmospheric Measurements (FAAM. We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS and used positive matrix factorization to separate hydrocarbon-like (HOA and oxygenated organic aerosols (OOA. We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA did change for

  20. 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

  1. 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...

  2. CATS Aerosol Typing and Future Directions

    Science.gov (United States)

    McGill, Matt; Yorks, John; Scott, Stan; Palm, Stephen; Hlavka, Dennis; Hart, William; Nowottnick, Ed; Selmer, Patrick; Kupchock, Andrew; Midzak, Natalie; Trepte, Chip; Vaughan, Mark; Colarco, Peter; da Silva, Arlindo

    2016-01-01

    The Cloud Aerosol Transport System (CATS), launched in January of 2015, is a lidar remote sensing instrument that will provide range-resolved profile measurements of atmospheric aerosols and clouds from the International Space Station (ISS). CATS is intended to operate on-orbit for at least six months, and up to three years. Status of CATS Level 2 and Plans for the Future:Version. 1. Aerosol Typing (ongoing): Mode 1: L1B data released later this summer; L2 data released shortly after; Identify algorithm biases (ex. striping, FOV (field of view) biases). Mode 2: Processed Released Currently working on correcting algorithm issues. Version 2 Aerosol Typing (Fall, 2016): Implementation of version 1 modifications Integrate GEOS-5 aerosols for typing guidance for non spherical aerosols. Version 3 Aerosol Typing (2017): Implementation of 1-D Var Assimilation into GEOS-5 Dynamic lidar ratio that will evolve in conjunction with simulated aerosol mixtures.

  3. 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...

  4. Charging of aerosol and nucleation in atmospheric pressure electrical discharges

    Science.gov (United States)

    Borra, J. P.

    2008-12-01

    The paper focuses on applications of atmospheric pressure plasmas (dc corona, streamer, spark and ac dielectric barrier discharges (DBDs)) in aerosol processes for materials and environment. Since aerosol kinematics depends mainly on electric forces acting on charged particles, the two mechanisms of aerosol charging by the collection of ions are presented in corona, post-corona and DBDs. In such defined charging conditions, field and diffusion charging laws are depicted, with respect to applications of controlled kinematics of charged aerosol. Then key parameters controlling the formation by nucleation and the growth by coagulation of particles in plasmas are presented. Sources of vapor leading to nucleated nanoparticles are depicted in atmospheric pressure electrical discharges: (i) when filamentary dc streamer and spark as well as ac-DBDs interact with metal or dielectric surfaces and (ii) when discharges induce reactions with gaseous precursors in volume. In both cases, condensable gaseous species are produced, leading to nano-sized particles by physical and chemical routes of nucleation. The composition, size and structure of primary nanoparticles as well as the final size of agglomerates are related to plasma parameters (energy, number per unit surface and time and thermal gradients around each filament as well as the transit time).

  5. Aerosol Emission during Human Speech

    Science.gov (United States)

    Asadi, Sima; Ristenpart, William

    2016-11-01

    The traditional emphasis for airborne disease transmission has been on coughing and sneezing, which are dramatic expiratory events that yield easily visible droplets. Recent research suggests that normal speech can release even larger quantities of aerosols that are too small to see with the naked eye, but are nonetheless large enough to carry a variety of pathogens (e.g., influenza A). This observation raises an important question: what types of speech emit the most aerosols? Here we show that the concentration of aerosols emitted during healthy human speech is positively correlated with both the amplitude (loudness) and fundamental frequency (pitch) of the vocalization. Experimental measurements with an aerodynamic particle sizer (APS) indicate that speaking in a loud voice (95 decibels) yields up to fifty times more aerosols than in a quiet voice (75 decibels), and that sounds associated with certain phonemes (e.g., [a] or [o]) release more aerosols than others. We interpret these results in terms of the egressive airflow rate associated with each phoneme and the corresponding fundamental frequency, which is known to vary significantly with gender and age. The results suggest that individual speech patterns could affect the probability of airborne disease transmission.

  6. The aerosol-climate model ECHAM5-HAM

    Directory of Open Access Journals (Sweden)

    P. Stier

    2005-01-01

    Full Text Available The aerosol-climate modelling system ECHAM5-HAM is introduced. It is based on a flexible microphysical approach and, as the number of externally imposed parameters is minimised, allows the application in a wide range of climate regimes. ECHAM5-HAM predicts the evolution of an ensemble of microphysically interacting internally- and externally-mixed aerosol populations as well as their size-distribution and composition. The size-distribution is represented by a superposition of log-normal modes. In the current setup, the major global aerosol compounds sulfate (SU, black carbon (BC, particulate organic matter (POM, sea salt (SS, and mineral dust (DU are included. The simulated global annual mean aerosol burdens (lifetimes for the year 2000 are for SU: 0.80 Tg(S (3.9 days, for BC: 0.11 Tg (5.4 days, for POM: 0.99 Tg (5.4 days, for SS: 10.5 Tg (0.8 days, and for DU: 8.28 Tg (4.6 days. An extensive evaluation with in-situ and remote sensing measurements underscores that the model results are generally in good agreement with observations of the global aerosol system. The simulated global annual mean aerosol optical depth (AOD is with 0.14 in excellent agreement with an estimate derived from AERONET measurements (0.14 and a composite derived from MODIS-MISR satellite retrievals (0.16. Regionally, the deviations are not negligible. However, the main patterns of AOD attributable to anthropogenic activity are reproduced.

  7. 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

  8. Dynamika aerosolů - matematická formulace, numerické řešení

    OpenAIRE

    Pušman, J. (Jan); Ždímal, V.

    2012-01-01

    Mathematical and computer modeling of aerosols is used in a wide range of applications including atmospheric physics and chemistry, environmental protection, nuclear safety and industrial applications such as the production of nanomaterials. The aim of this work is twofold. We present a closer look at some aspects of mathematical modeling of aerosols as sub-discipline of continuum mechanics. We provide an overview of common methods and we discuss limitations on their applicability. The long-...

  9. Identification of origin of single aerosol particles using polycapillary X-ray lens

    Energy Technology Data Exchange (ETDEWEB)

    Sun Tianxi [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China) and Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China) and Beijing Radiation Center, Beijing 100875 (China)], E-mail: stxbeijing@163.com; Liu Zhiguo; Zhu Guanghua; Liu Hui [Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China); Xu Qing [Institute of High Energy Physics, Chinese Academy of Science, Beijing 100039 (China); Li Yude; Wang Guangpu; Sun Hongbo; Luo Ping; Pan Qiuli; Ding Xunliang [The Key Laboratory of Beam Technology and Materials Modification of Ministry of Education, Beijing Normal University, Beijing 100875 (China); Institute of Low Energy Nuclear Physics, Beijing Normal University, Beijing 100875 (China); Beijing Radiation Center, Beijing 100875 (China)

    2009-01-15

    A micro X-ray fluorescence (Micro-XRF) spectrometer based on a polycapillary focusing X-ray lens (PFXRL) and a laboratory X-ray source was designed to carry out the XRF analysis of single aerosol particles. The minimum detection limit (MDL) of this Micro-XRF spectrometer was 9 ppm for the Fe-K{alpha}. The percentage of the particles of vehicle exhaust among aerosol particles was studied in Beijing, Chinese capital, during the test of odd-even driving restrictions for Beijing 2008 Olympics Games. This Micro-XRF spectrometer had potential applications in the analysis of single aerosol particles.

  10. Enhanced Fullerene Yield in Plasma-Aerosol Reactor at Cryogenic Boundary Temperature

    CERN Document Server

    Jouravlev, Mikhail

    2011-01-01

    We demonstrate remarkably enhanced yield of C60 fullerenes in an aerosol discharge chamber due to the additional presence of a strong spatial temperature gradient. The role of the temperature gradients in the increased yield of C60 and fullerene-like structures is discussed. The reaction is not fully reversible and carbon soot matter is formed as a secondary product in the form of carbon aerosol particles. The increasing concentration of C60 was easily recognized from the characteristic UV-spectra. The result of this paper will be useful for improvement of fullerene synthesis technology and for application to constructing new types of aerosol-plasma reactors.

  11. ATI TDA 5A aerosol generator evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Gilles, D.A.

    1998-07-27

    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.

  12. DARE: a dedicated aerosols retrieval instrument

    NARCIS (Netherlands)

    Court, A.J.; Smorenburg, K.; Courrèges-Lacoste, G.B.; Visser, H.; Leeuw, G. de; Decae, R.

    2004-01-01

    Satellite remote sensing of aerosols is a largely unresolved problem. A dedicated instrument aimed at aerosols would be able to reduce the large uncertainties connected to this kind of remote sensing. TNO is performing a study of a space based instrument for aerosol measurements, together with the s

  13. Highly Resolved Paleoclimatic Aerosol Records

    DEFF Research Database (Denmark)

    Kettner, Ernesto

    In ice cores a plethora of proxies for paleoclimatic conditions is archived. Air trapped in the ice during firnification allows for direct measurements of the concentrations and isotope ratios of paleoatmospheric gases while, the isotopic composition of the ice matrix itself is related...... 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...

  14. Wind reduction by aerosol particles

    Science.gov (United States)

    Jacobson, Mark Z.; Kaufman, Yoram J.

    2006-12-01

    Aerosol particles are known to affect radiation, temperatures, stability, clouds, and precipitation, but their effects on spatially-distributed wind speed have not been examined to date. Here, it is found that aerosol particles, directly and through their enhancement of clouds, may reduce near-surface wind speeds below them by up to 8% locally. This reduction may explain a portion of observed ``disappearing winds'' in China, and it decreases the energy available for wind-turbine electricity. In California, slower winds reduce emissions of wind-driven soil dust and sea spray. Slower winds and cooler surface temperatures also reduce moisture advection and evaporation. These factors, along with the second indirect aerosol effect, may reduce California precipitation by 2-5%, contributing to a strain on water supply.

  15. 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

  16. Aerosol retrieval experiments in the ESA Aerosol_cci project

    Science.gov (United States)

    Holzer-Popp, T.; de Leeuw, G.; Griesfeller, J.; Martynenko, D.; Klüser, L.; Bevan, S.; Davies, W.; Ducos, F.; Deuzé, J. L.; Graigner, R. G.; Heckel, A.; von Hoyningen-Hüne, W.; Kolmonen, P.; Litvinov, P.; North, P.; Poulsen, C. A.; Ramon, D.; Siddans, R.; Sogacheva, L.; Tanre, D.; Thomas, G. E.; Vountas, M.; Descloitres, J.; Griesfeller, J.; Kinne, S.; Schulz, M.; Pinnock, S.

    2013-08-01

    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 photometer

  17. Aerosol profile information from high resolution oxygen A-Band measurements from space

    Directory of Open Access Journals (Sweden)

    A. Geddes

    2014-06-01

    Full Text Available Aerosols are an important factor of the Earth climatic system and they play a key role for air quality and public health. Observations of the oxygen A-Band at 760 nm can provide information on the vertical distribution of aerosols from passive satellite sensors, that can be of great interest for operational monitoring applications with high coverage if the aerosol information is obtained with sufficient precision, accuracy and vertical resolution. To address this issue, retrieval simulations of the aerosol vertical profile retrieval from O2 A Band observations by GOSAT, the upcoming OCO-2 and Sentinel 5-P mission and the proposed CarbonSat mission have been carried out. Precise retrievals of AOD within the boundary layer were found to favour low resolution, high SNR instruments such as Sentinel-5 P, whereas higher resolution instruments such as OCO-2 showed greater performance at higher altitudes and in information content above the boundary layer. Accurate retrievals of the AOD in the 0–2 km range appears difficult from all studied instruments and the retrieval errors typically exceed a value of 0.05. Constraining the surface albedo is a promising and effective way of improving the retrieval of aerosol, but the required level of a priori knowledge is very high. Due to the limited information content of the aerosol profile retrieval, the use of a parameterised aerosol distribution has been assessed and we show that the AOD and height of an aerosol layer can be retrieved well if the aerosol layer is uplifted to the free troposphere but errors are often large for aerosol layers in the boundary layer. Additional errors will be introduced by incorrect assumptions on surface pressure and aerosol type which can both bias retrieved AOD and height by up to 40%. We conclude the aerosol profile retrievals from O2 A Band using existing or upcoming satellite sensors will only provide limited information on aerosols in the boundary layer but such

  18. Resolution and Content Improvements to MISR Aerosol and Land Surface Products

    Science.gov (United States)

    Garay, M. J.; Bull, M. A.; Diner, D. J.; Hansen, E. G.; Kalashnikova, O. V.

    2015-12-01

    Since early 2000, the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite has been providing operational Level 2 (swath-based) aerosol optical depth (AOD) and particle property retrievals at 17.6 km spatial resolution and atmospherically corrected land surface products at 1.1 km resolution. The performance of the aerosol product has been validated against ground-based Aerosol Robotic Network (AERONET) observations, model comparisons, and climatological assessments. This product has played a major role in studies of the impacts of aerosols on climate and air quality. The surface product has found a variety of uses, particularly at regional scales for assessing vegetation and land surface change. A major development effort has led to the release of an update to the operational (Version 22) MISR Level 2 aerosol and land surface retrieval products, which has been in production since December 2007. The new release is designated Version 23. The resolution of the aerosol product has been increased to 4.4 km, allowing more detailed characterization of aerosol spatial variability, especially near local sources and in urban areas. The product content has been simplified and updated to include more robust measures of retrieval uncertainty and other fields to benefit users. The land surface product has also been updated to incorporate the Version 23 aerosol product as input and to improve spatial coverage, particularly over mountainous terrain and snow/ice-covered surfaces. We will describe the major upgrades incorporated in Version 23 and present validation of the aerosol product against both the standard AERONET historical database, as well as high spatial density AERONET-DRAGON deployments. Comparisons will also be shown relative to the Version 22 aerosol and land surface products. Applications enabled by these product updates will be discussed.

  19. A simplified model of aerosol removal by natural processes in reactor containments

    Energy Technology Data Exchange (ETDEWEB)

    Powers, D.A.; Washington, K.E.; Sprung, J.L. [Sandia National Labs., Albuquerque, NM (United States); Burson, S.B. [Nuclear Regulatory Commission, Washington, DC (United States)

    1996-07-01

    Simplified formulae are developed for estimating the aerosol decontamination that can be achieved by natural processes in the containments of pressurized water reactors and in the drywells of boiling water reactors under severe accident conditions. These simplified formulae were derived by correlation of results of Monte Carlo uncertainty analyses of detailed models of aerosol behavior under accident conditions. Monte Carlo uncertainty analyses of decontamination by natural aerosol processes are reported for 1,000, 2,000, 3,000, and 4,000 MW(th) pressurized water reactors and for 1,500, 2,500, and 3,500 MW(th) boiling water reactors. Uncertainty distributions for the decontamination factors and decontamination coefficients as functions of time were developed in the Monte Carlo analyses by considering uncertainties in aerosol processes, material properties, reactor geometry and severe accident progression. Phenomenological uncertainties examined in this work included uncertainties in aerosol coagulation by gravitational collision, Brownian diffusion, turbulent diffusion and turbulent inertia. Uncertainties in aerosol deposition by gravitational settling, thermophoresis, diffusiophoresis, and turbulent diffusion were examined. Electrostatic charging of aerosol particles in severe accidents is discussed. Such charging could affect both the coagulation and deposition of aerosol particles. Electrostatic effects are not considered in most available models of aerosol behavior during severe accidents and cause uncertainties in predicted natural decontamination processes that could not be taken in to account in this work. Median (50%), 90 and 10% values of the uncertainty distributions for effective decontamination coefficients were correlated with time and reactor thermal power. These correlations constitute a simplified model that can be used to estimate the decontamination by natural aerosol processes at 3 levels of conservatism. Applications of the model are described.

  20. 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

  1. Reseña de: Pedro C. Cerrillo y M.ª Teresa Miaja, Sobre 'zazaniles' y 'quisicosas': estudio del género de la adivinanza, Colección Arcadia, n.º 20, Cuenca, Universidad de Castilla-La Mancha, 2011, 142 pp.

    OpenAIRE

    Beltrán Llavador, Rafael

    2013-01-01

    Los autores de la obra que reseñamos cuentan con una dilatada trayectoria de tra-bajo en torno a la literatura y la tradición oral: Pedro Cerrillo, como un infatigable in-vestigador y reivindicador de la literatura infantil y juvenil, de la tradición oral y de la educación literaria, tanto desde la Universidad como desde el CEPLI (Centro de Estu-dios de Promoción de la Lectura y Literatura Infantil), que dirige; M.ª Teresa Miaja, como estudiosa de la literatura española en especial la mediev...

  2. Aerosol effects on deep convective clouds: impact of changes in aerosol size distribution and aerosol activation parameterization

    Science.gov (United States)

    Ekman, A. M. L.; Engström, A.; Söderberg, A.

    2010-03-01

    A cloud-resolving model including explicit aerosol physics and chemistry is used to study the impact of aerosols on deep convective strength. More specifically, by conducting six sensitivity series we examine how the complexity of the aerosol model, the size of the aerosols and the aerosol activation parameterization influence the aerosol-induced deep convective cloud sensitivity. Only aerosol effects on liquid droplet formation are considered. We find that an increased aerosol concentration generally results in stronger convection, which for the simulated case is in agreement with the conceptual model presented by Rosenfeld et al. (2008). However, there are two sensitivity series that do not display a monotonic increase in updraft velocity with increasing aerosol concentration. These exceptions illustrate the need to: 1) account for changes in evaporation processes and subsequent cooling when assessing aerosol effects on deep convective strength, 2) better understand graupel impaction scavenging of aerosols which may limit the number of CCN at a critical stage of cloud development and thereby dampen the convection, 3) increase our knowledge of aerosol recycling due to evaporation of cloud droplets. Furthermore, we find a significant difference in the aerosol-induced deep convective cloud sensitivity when using different complexities of the aerosol model and different aerosol activation parameterizations. For the simulated case, a 100% increase in aerosol concentration results in a difference in average updraft between the various sensitivity series which is as large as the average updraft increase itself. The model simulations also show that the change in graupel and rain formation is not necessarily directly proportional to the change in updraft velocity. For example, several of the sensitivity series display a decrease of the rain amount at the lowest model level with increasing updraft velocity. Finally, an increased number of aerosols in the Aitken mode (here

  3. Aerosol effects on deep convective clouds: impact of changes in aerosol size distribution and aerosol activation parameterization

    Directory of Open Access Journals (Sweden)

    A. M. L. Ekman

    2010-03-01

    Full Text Available A cloud-resolving model including explicit aerosol physics and chemistry is used to study the impact of aerosols on deep convective strength. More specifically, by conducting six sensitivity series we examine how the complexity of the aerosol model, the size of the aerosols and the aerosol activation parameterization influence the aerosol-induced deep convective cloud sensitivity. Only aerosol effects on liquid droplet formation are considered. We find that an increased aerosol concentration generally results in stronger convection, which for the simulated case is in agreement with the conceptual model presented by Rosenfeld et al. (2008. However, there are two sensitivity series that do not display a monotonic increase in updraft velocity with increasing aerosol concentration. These exceptions illustrate the need to: 1 account for changes in evaporation processes and subsequent cooling when assessing aerosol effects on deep convective strength, 2 better understand graupel impaction scavenging of aerosols which may limit the number of CCN at a critical stage of cloud development and thereby dampen the convection, 3 increase our knowledge of aerosol recycling due to evaporation of cloud droplets. Furthermore, we find a significant difference in the aerosol-induced deep convective cloud sensitivity when using different complexities of the aerosol model and different aerosol activation parameterizations. For the simulated case, a 100% increase in aerosol concentration results in a difference in average updraft between the various sensitivity series which is as large as the average updraft increase itself. The model simulations also show that the change in graupel and rain formation is not necessarily directly proportional to the change in updraft velocity. For example, several of the sensitivity series display a decrease of the rain amount at the lowest model level with increasing updraft velocity. Finally, an increased number of aerosols in the

  4. Systematic aerosol characterization by combining GOME-2 UV Aerosol Indices with trace gas concentrations

    Science.gov (United States)

    Penning de Vries, M.; Stammes, P.; Wagner, T.

    2012-04-01

    The task of determining aerosol type using passive remote sensing instruments is a daunting one. First, because the variety in aerosol (optical) properties is very large; and second, because the effect of aerosols on the detected top-of-atmosphere reflectance spectrum is smooth and mostly featureless. In addition, spectrometers like GOME-2 have a coarse spatial resolution, which makes aerosol characterization even more difficult due to interferences with clouds. On account of these problems, we do not attempt to derive aerosol properties from single measurements: instead, we combine time series of UV Aerosol Index and trace gas concentrations to derive the dominating aerosol type for each season. Aside from the Index values and trace gas concentrations themselves, the correlation between UV Aerosol Indices (which are indicative of aerosol absorption) with NO2, HCHO, and CHOCHO columns - or absence of it - provides clues to the (main) source of the aerosols in the investigated region and time range. For example: a high correlation of HCHO and Absorbing Aerosol Index points to aerosols from biomass burning, highly correlated CHOCHO, HCHO, and SCattering Index indicate biogenic secondary organic aerosols, and coinciding high NO2 concentrations with high SCattering Index values are associated with industrial and urban aerosols. We here present case studies for several regions to demonstrate the suitability of our approach. Then, we introduce a method to systematically derive the dominating aerosol type on a global scale on time scales varying from monthly to yearly.

  5. Analysis of the Interaction and Transport of Aerosols with Cloud or Fog in East Asia from AERONET and Satellite Remote Sensing: 2012 DRAGON Campaigns and Climatological Data

    Science.gov (United States)

    Eck, T. F.; Holben, B. N.; Reid, J. S.; Lynch, P.; Schafer, J.; Giles, D. M.; Kim, J.; Kim, Y. J.; Sano, I.; Arola, A. T.; Munchak, L. A.; O'Neill, N. T.; Lyapustin, A.; Sayer, A. M.; Hsu, N. Y. C.; Randles, C. A.; da Silva, A. M., Jr.; Govindaraju, R.; Hyer, E. J.; Pickering, K. E.; Crawford, J. H.; Sinyuk, A.; Smirnov, A.

    2015-12-01

    Ground-based remote sensing observations from Aerosol Robotic Network (AERONET) sun-sky radiometers have recently shown several instances where cloud-aerosol interaction had resulted in modification of aerosol properties and/or in difficulty identifying some major pollution transport events due to aerosols being imbedded in cloud systems. Major Distributed Regional Aerosol Gridded Observation Networks (DRAGON) field campaigns involving multiple AERONET sites in Japan and South Korea during Spring of 2012 have yielded observations of aerosol transport associated with clouds and/or aerosol properties modification as a result of fog interaction. Analysis of data from the Korean and Japan DRAGON campaigns shows that major fine-mode aerosol transport events are sometimes associated with extensive cloud cover and that cloud-screening of observations often filter out significant pollution aerosol transport events. The Spectral De-convolution Algorithm (SDA) algorithm was utilized to isolate and analyze the fine-mode aerosol optical depth (AODf) signal from AERONET data for these cases of persistent and extensive cloud cover. Satellite retrievals of AOD from MODIS sensors (from Dark Target, Deep Blue and MAIAC algorithms) were also investigated to assess the issue of detectability of high AOD events associated with high cloud fraction. Underestimation of fine mode AOD by the Navy Aerosol Analysis and Prediction System (NAAPS) and by the NASA Modern-Era Retrospective Analysis For Research And Applications Aerosol Re-analysis (MERRAaero) models at very high AOD at sites in China and Korea was observed, especially for observations that are cloud screened by AERONET (Level 2 data). Additionally, multi-year monitoring at several AERONET sites are examined for climatological statistics of cloud screening of fine mode aerosol events. Aerosol that has been affected by clouds or the near-cloud environment may be more prevalent than AERONET data suggest due to inherent difficulty in

  6. AERONET-based models of smoke-dominated aerosol near source regions and transported over oceans, and implications for satellite retrievals of aerosol optical depth

    Science.gov (United States)

    Sayer, A. M.; Hsu, N. C.; Eck, T. F.; Smirnov, A.; Holben, B. N.

    2014-10-01

    Smoke aerosols from biomass burning are an important component of the global aerosol system. Analysis of Aerosol Robotic Network (AERONET) retrievals of aerosol microphysical/optical parameters at 10 sites reveals variety between biomass burning aerosols in different global source regions, in terms of aerosol particle size and single scatter albedo (SSA). Case studies of smoke observed at coastal/island AERONET sites also mostly lie within the range of variability at the near-source sites. Differences between sites tend to be larger than variability at an individual site, although optical properties for some sites in different regions can be quite similar. Across the sites, typical midvisible SSA ranges from ~ 0.95-0.97 (sites dominated by boreal forest or peat burning, typically with larger fine-mode particle radius and spread) to ~ 0.88-0.9 (sites most influenced by grass, shrub, or crop burning, typically smaller fine-mode particle radius and spread). The tropical forest site Alta Floresta (Brazil) is closer to this second category, although with intermediate SSA ~ 0.92. The strongest absorption is seen in southern African savannah at Mongu (Zambia), with average midvisible SSA ~ 0.85. Sites with stronger absorption also tend to have stronger spectral gradients in SSA, becoming more absorbing at longer wavelengths. Microphysical/optical models are presented in detail so as to facilitate their use in radiative transfer calculations, including extension to UV (ultraviolet) wavelengths, and lidar ratios. One intended application is to serve as candidate optical models for use in satellite aerosol optical depth (AOD) retrieval algorithms. The models presently adopted by these algorithms over ocean often have insufficient absorption (i.e. too high SSA) to represent these biomass burning aerosols. The underestimates in satellite-retrieved AOD in smoke outflow regions, which have important consequences for applications of these satellite data sets, are consistent with

  7. Novel aerosol analysis approach for characterization of nanoparticulate matter in snow.

    Science.gov (United States)

    Nazarenko, Yevgen; Rangel-Alvarado, Rodrigo B; Kos, Gregor; Kurien, Uday; Ariya, Parisa A

    2016-12-10

    Tropospheric aerosols are involved in several key atmospheric processes: from ice nucleation, cloud formation, and precipitation to weather and climate. The impact of aerosols on these atmospheric processes depends on the chemical and physical characteristics of aerosol particles, and these characteristics are still largely uncertain. In this study, we developed a system for processing and aerosolization of melted snow in particle-free air, coupled with a real-time measurement of aerosol size distributions. The newly developed technique involves bringing snow-borne particles into an airborne state, which enables application of high-resolution aerosol analysis and sampling techniques. This novel analytical approach was compared to a variety of complementary existing analytical methods as applied for characterization of snow samples from remote sites in Alert (Canada) and Barrow (USA), as well as urban Montreal (Canada). The dry aerosol measurements indicated a higher abundance of particles of all sizes, and the 30 nm size dominated in aerosol size distributions for the Montreal samples, closely followed by Barrow, with about 30% fewer 30 nm particles, and about four times lower 30 nm particle abundance in Alert samples, where 15 nm particles were most abundant instead. The aerosolization technique, used together with nanoparticle tracking analysis and electron microscopy, allowed measurement of a wide size range of snow-borne particles in various environmental snow samples. Here, we discuss the application of the new technique to achieve better physicochemical understanding of atmospheric and snow processes. The results showed high sensitivity and reduction of particle aggregation, as well as the ability to measure a high-resolution snow-borne particle size distribution, including nanoparticulate matter in the range of 10 to 100 nm.

  8. 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

  9. 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...

  10. Technical Report Series on Global Modeling and Data Assimilation. Volume 32; Estimates of AOD Trends (2002 - 2012) Over the World's Major Cities Based on the MERRA Aerosol Reanalysis

    Science.gov (United States)

    Provencal, Simon; Kishcha, Pavel; Elhacham, Emily; daSilva, Arlindo M.; Alpert, Pinhas; Suarez, Max J.

    2014-01-01

    NASA's Global Modeling and Assimilation Office has extended the Modern-Era Retrospective Analysis for Research and Application (MERRA) tool with five atmospheric aerosol species (sulfates, organic carbon, black carbon, mineral dust and sea salt). This inclusion of aerosol reanalysis data is now known as MERRAero. This study analyses a ten-year period (July 2002 - June 2012) MERRAero aerosol reanalysis applied to the study of aerosol optical depth (AOD) and its trends for the aforementioned aerosol species over the world's major cities (with a population of over 2 million inhabitants). We found that a proportion of various aerosol species in total AOD exhibited a geographical dependence. Cities in industrialized regions (North America, Europe, central and eastern Asia) are characterized by a strong proportion of sulfate aerosols. Organic carbon aerosols are dominant over cities which are located in regions where biomass burning frequently occurs (South America and southern Africa). Mineral dust dominates other aerosol species in cities located in proximity to the major deserts (northern Africa and western Asia). Sea salt aerosols are prominent in coastal cities but are dominant aerosol species in very few of them. AOD trends are declining over cities in North America, Europe and Japan, as a result of effective air quality regulation. By contrast, the economic boom in China and India has led to increasing AOD trends over most cities in these two highly-populated countries. Increasing AOD trends over cities in the Middle East are caused by increasing desert dust.

  11. Ceilometer for aerosol profiling: comparison with the multiwavelength in the frame of INTERACT (INTERcomparison of Aerosol and Cloud Tracking)

    Science.gov (United States)

    Madonna, Fabio; Vande Hey, Joshua; Rosoldi, Marco; Amato, Francesco; Pappalardo, Gelsomina

    2015-04-01

    Observations of cloud base height are important for meteorology, observations of aerosols are important for air quality applications, observations of cloud cover and aerosols address key uncertainties in climate study. To improve parameterization and uncertainties of numerical models, observations provided by high resolution networks of ground-based instruments are needed. In order to achieve broad, high resolution coverage, low-cost instruments are preferable, though it is essential that the sensitivity, stability, biases and uncertainties of these instruments are well-understood. Despite of their differences from more advanced and more powerful lidars, low construction and operation cost of ceilometer, originally designed for cloud base height monitoring, has fostered their use for the quantitative study of aerosol properties. The large number of ceilometers available worldwide represent a strong motivation to investigate to which extent they can be used to fill the geographical gaps between advanced lidar stations and how their continuous data flow can be linked to existing networks of the advanced lidars, like EARLINET (European Aerosol research LIdar NETwork). In order to make the best use of existing and future ceilometer deployments, ceilometer must be better characterized. This is the purpose of the INTERACT campaign carried out in the frame of ACTRIS Transnational Access activities at CNR-IMAA Atmospheric Observatory (CIAO - 760 m a.s.l., 40.60 N, 15.72 E). In this paper, an overview of the results achieved during the campaign is provided. In particular multi-wavelength Raman lidar measurements are used to investigate the capability of ceilometers to provide reliable information about atmospheric aerosol content through the INTERACT (INTERcomparison of Aerosol and Cloud Tracking) campaign carried out at the CNR-IMAA Atmospheric Observatory (760 m a.s.l., 40.60N, 15.72E), in the framework of ACTRIS (Aerosol Clouds Trace gases Research InfraStructure) FP7

  12. High Concentration Standard Aerosol Generator.

    Science.gov (United States)

    1985-07-31

    materials. In addition to material problems, many liquids are extremely flammable or explosive when aerosolized. This can be checked by putting a small...Hochriner. D. (1975) Stub 3A 440-445. St6ber, W. Flachsbart, H. and Hochramn, D. (1970) Staub 3^, 277. Yoshida. H. Fujii, K. Yomimoto, Y. Masuda. H. and

  13. Aerosol Microphysics and Radiation Integration

    Science.gov (United States)

    2016-06-07

    1. REPORT DATE 30 SEP 2003 2. REPORT TYPE 3. DATES COVERED 00-00-2003 to 00-00-2003 4. TITLE AND SUBTITLE Aerosol Microphysics and Radiation...Airborne Radiometric Measurements.’ Bucholtz, A. (as member of CRYSTAL-FACE Science Team), NASA 2003 Group Achievement Award to CRYSTAL-FACE

  14. 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

  15. Airborne Atmospheric Aerosol Measurement System

    Science.gov (United States)

    Ahn, K.; Park, Y.; Eun, H.; Lee, H.

    2015-12-01

    It is important to understand the atmospheric aerosols compositions and size distributions since they greatly affect the environment and human health. Particles in the convection layer have been a great concern in global climate changes. To understand these characteristics satellite, aircraft, and radio sonde measurement methods have usually been used. An aircraft aerosol sampling using a filter and/or impactor was the method commonly used (Jay, 2003). However, the flight speed particle sampling had some technical limitations (Hermann, 2001). Moreover, the flight legal limit, altitude, prohibited airspace, flight time, and cost was another demerit. To overcome some of these restrictions, Tethered Balloon Package System (T.B.P.S.) and Recoverable Sonde System(R.S.S.) were developed with a very light optical particle counter (OPC), impactor, and condensation particle counter (CPC). Not only does it collect and measure atmospheric aerosols depending on altitudes, but it also monitors the atmospheric conditions, temperature, humidity, wind velocity, pressure, GPS data, during the measurement (Eun, 2013). In this research, atmospheric aerosol measurement using T.B.P.S. in Ansan area is performed and the measurement results will be presented. The system can also be mounted to an unmanned aerial vehicle (UAV) and create an aerial particle concentration map. Finally, we will present measurement data using Tethered Balloon Package System (T.B.P.S.) and R.S.S (Recoverable Sonde System).

  16. Aerosol and monsoon climate interactions over Asia: AEROSOL AND MONSOON CLIMATE INTERACTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhanqing [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Lau, W. K. -M. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Ramanathan, V. [Department of Atmospheric and Climate Sciences, University of California, San Diego California USA; Wu, G. [Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing China; Ding, Y. [National Climate Center, China Meteorological Administration, Beijing China; Manoj, M. G. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Liu, J. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Qian, Y. [Pacific Northwest National Laboratory, Richland Washington USA; Li, J. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Zhou, T. [Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing China; Fan, J. [Pacific Northwest National Laboratory, Richland Washington USA; Rosenfeld, D. [Institute of Earth Sciences, Hebrew University, Jerusalem Israel; Ming, Y. [Geophysical Fluid Dynamic Laboratory, NOAA, Princeton New Jersey USA; Wang, Y. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena California USA; Huang, J. [College of Atmospheric Sciences, Lanzhou University, Lanzhou China; Wang, B. [Department of Atmospheric Sciences, University of Hawaii, Honolulu Hawaii USA; School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing China; Xu, X. [Chinese Academy of Meteorological Sciences, Beijing China; Lee, S. -S. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Cribb, M. [Department of Atmospheric and Oceanic Science and ESSIC, University of Maryland, College Park Maryland USA; Zhang, F. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Yang, X. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Zhao, C. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Takemura, T. [Research Institute for Applied Mechanics, Kyushu University, Fukuoka Japan; Wang, K. [State Key Laboratory of Earth Surface Processes and Resource Ecology and College of Global Change and Earth System Science, Beijing Normal University, Beijing China; Xia, X. [Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing China; Yin, Y. [School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing China; Zhang, H. [National Climate Center, China Meteorological Administration, Beijing China; Guo, J. [Chinese Academy of Meteorological Sciences, Beijing China; Zhai, P. M. [Chinese Academy of Meteorological Sciences, Beijing China; Sugimoto, N. [National Institute for Environmental Studies, Tsukuba Japan; Babu, S. S. [Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram India; Brasseur, G. P. [Max Planck Institute for Meteorology, Hamburg Germany

    2016-11-15

    Asian monsoons and aerosols have been studied extensively which are intertwined in influencing the climate of Asia. This paper provides a comprehensive review of ample studies on Asian aerosol, monsoon and their interactions. The region is the primary source of aerosol emissions of varies species, influenced by distinct weather and climatic regimes. On continental scale, aerosols reduce surface insolation and weaken the land-ocean thermal contrast, thus inhibiting the development of monsoons. Locally, aerosol radiative effects alter the thermodynamic stability and convective potential of the lower atmosphere leading to reduced temperatures, increased atmospheric stability, and weakened wind and atmospheric circulation. The atmospheric thermodynamic state may also be altered by the aerosol serving as cloud condensation nuclei or ice nuclei. Many mechanisms have been put forth regarding how aerosols modulate the amplitude, frequency, intensity, and phase of numerous monsoon climate variables. A wide range of theoretical, observational, and modeling findings on the Asian monsoon, aerosols, and their interactions are synthesized. A new paradigm is proposed on investigating aerosol-monsoon interactions, in which natural aerosols such as desert dust, black carbon from biomass burning, and biogenic aerosols from vegetation are considered integral components of an intrinsic aerosol-monsoon climate system, subject to external forcings of global warming, anthropogenic aerosols, and land use and change. Future research on aerosol-monsoon interactions calls for an integrated approach and international collaborations based on long-term sustained observations, process measurements, and improved models, as well as using observations to constrain model simulations and projections.

  17. Biofilm Removal Using Carbon Dioxide Aerosols without Nitrogen Purge.

    Science.gov (United States)

    Hong, Seongkyeol; Jang, Jaesung

    2016-11-06

    Biofilms can cause serious concerns in many applications. Not only can they cause economic losses, but they can also present a public health hazard. Therefore, it is highly desirable to remove biofilms from surfaces. Many studies on CO2 aerosol cleaning have employed nitrogen purges to increase biofilm removal efficiency by reducing the moisture condensation generated during the cleaning. However, in this study, periodic jets of CO2 aerosols without nitrogen purges were used to remove Pseudomonas putida biofilms from polished stainless steel surfaces. CO2 aerosols are mixtures of solid and gaseous CO2 and are generated when high-pressure CO2 gas is adiabatically expanded through a nozzle. These high-speed aerosols were applied to a biofilm that had been grown for 24 hr. The removal efficiency ranged from 90.36% to 98.29% and was evaluated by measuring the fluorescence intensity of the biofilm as the treatment time was varied from 16 sec to 88 sec. We also performed experiments to compare the removal efficiencies with and without nitrogen purges; the measured biofilm removal efficiencies were not significantly different from each other (t-test, p > 0.55). Therefore, this technique can be used to clean various bio-contaminated surfaces within one minute.

  18. Amphiphobic Polytetrafluoroethylene Membranes for Efficient Organic Aerosol Removal.

    Science.gov (United States)

    Feng, Shasha; Zhong, Zhaoxiang; Zhang, Feng; Wang, Yong; Xing, Weihong

    2016-04-06

    Polytetrafluoroethylene (PTFE) membrane is an extensively used air filter, but its oleophilicity leads to severe fouling of the membrane surface due to organic aerosol deposition. Herein, we report the fabrication of a new amphiphobic 1H,1H,2H,2H-perfluorodecyl acrylate (PFDAE)-grafted ZnO@PTFE membrane with enhanced antifouling functionality and high removal efficiency. We use atomic-layer deposition (ALD) to uniformly coat a layer of nanosized ZnO particles onto porous PTFE matrix to increase surface area and then subsequently graft PFDAE with plasma. Consequently, the membrane surface showed both superhydrophobicity and oleophobicity with a water contact angle (WCA) and an oil contact angle (OCA) of 150° and 125°, respectively. The membrane air permeation rate of 513 (m(3) m(-2) h(-1) kPa(-1)) was lower than the pristine membrane rate of 550 (m(3) m(-2) h(-1) kPa(-1)), which indicates the surface modification slightly decreased the membrane air permeation. Significantly, the filtration resistance of this amphiphobic membrane to the oil aerosol system was much lower than the initial one. Moreover, the filter exhibited exceptional organic aerosol removal efficiencies that were greater than 99.5%. These results make the amphiphobic PTFE membranes very promising for organic aerosol-laden air-filtration applications.

  19. Atmospheric pressure plasmas for aerosols processes in materials and environment

    Science.gov (United States)

    Borra, J. P.; Jidenko, N.; Bourgeois, E.

    2009-08-01

    The paper highlights applications of some atmospheric pressure plasmas (dc-corona, streamer and spark and ac-Dielectric Barrier Discharges) to aerosol processes for Materials and Environment (filtration, diagnostics). The production of vapor i.e. condensable gaseous species, leads to nano-sized particles by physical and chemical routes of nucleation in these AP plasmas: (i) when dc streamer and spark filamentary discharges as well as ac filamentary dielectric barrier discharges interact with metal or dielectric surfaces, and (ii) when discharges induce reactions with gaseous precursors in volume. It is shown how composition, size and structure of primary nano-particles are related to plasma parameters (energy, number per unit surface and time and thermal gradients). Then the growth by coagulation controls the final size of agglomerates versus plasma parameters and transit time in and after the plasma. Charging and electro-thermal collection are depicted to account for the related potential applications of controlled kinematics of charged aerosol.

  20. 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

  1. Dust aerosol impact on North Africa climate: a GCM investigation of aerosol-cloud-radiation interactions using A-Train satellite data

    Directory of Open Access Journals (Sweden)

    Y. Gu

    2011-12-01

    Full Text Available The climatic effects of dust aerosols in North Africa have been investigated using the atmospheric general circulation model (AGCM developed at the University of California, Los Angeles (UCLA. The model includes an efficient and physically based radiation parameterization scheme developed specifically for application to clouds and aerosols. Parameterization of the effective ice particle size in association with the aerosol first indirect effect based on ice cloud and aerosol data retrieved from A-Train satellite observations have been employed in climate model simulations. Offline simulations reveal that the direct solar, IR, and net forcings by dust aerosols at the top of the atmosphere (TOA generally increase with increasing aerosol optical depth (AOD. When the dust semi-direct effect is included with the presence of ice clouds, positive IR radiative forcing is enhanced since ice clouds trap substantial IR radiation, while the positive solar forcing with dust aerosols alone has been changed to negative values due to the strong reflection of solar radiation by clouds, indicating that cloud forcing associated with aerosol semi-direct effect could exceed direct aerosol forcing. With the aerosol first indirect effect, the net cloud forcing is generally reduced for an ice water path (IWP larger than 20 g m−2. The magnitude of the reduction increases with IWP.

    AGCM simulations show that the reduced ice crystal mean effective size due to the aerosol first indirect effect results in less OLR and net solar flux at the top of the atmosphere over the cloudy area of the North Africa region because ice clouds with smaller size trap more IR radiation and reflect more solar radiation. The precipitation in the same area, however, increases due to the aerosol indirect effect on ice clouds, corresponding to the enhanced convection as indicated by reduced OLR. The increased precipitation appears to be associated with enhanced ice water

  2. Basic phenomena utilised in aerosol particle measurement techniques; Hiukkasmittaustekniikoiden perusilmioet

    Energy Technology Data Exchange (ETDEWEB)

    Janka, K. [Dekati Oy, Tampere (Finland)

    2006-10-15

    The project deals with development of basic phenomena and mechanism utilised in aerosol particle measurement techniques. The areas under development are: particle-charging techniques, photoelectric charging, particle concentrating using virtual-impactor technique, and optical characterising techniques of particles. Results will be applied on detection techniques of bioaerosol attract, particle emission sensors for diesel exhaust gases, and widening the application areas of existing measurement techniques. (orig.)

  3. Laboratory Testing of Aerosol for Enclosure Air Sealing

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, C.; Modera, M.

    2012-05-01

    Space conditioning energy use can be significantly reduced by addressing uncontrolled infiltration and exfiltration through the envelope of a building. A process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology is presented. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

  4. MAC-v1: A new global aerosol climatology for climate studies

    Science.gov (United States)

    Kinne, Stefan; O'Donnel, Declan; Stier, Philip; Kloster, Silvia; Zhang, Kai; Schmidt, Hauke; Rast, Sebastian; Giorgetta, Marco; Eck, Tom F.; Stevens, Bjorn

    2013-12-01

    The Max-Planck-Institute Aerosol Climatology version 1 (MAC-v1) is introduced. It describes the optical properties of tropospheric aerosols on monthly timescales and with global coverage at a spatial resolution of 1° in latitude and longitude. By providing aerosol radiative properties for any wavelength of the solar (or shortwave) and of the terrestrial (or longwave) radiation spectrum, as needed in radiative transfer applications, this MAC-v1 data set lends itself to simplified and computationally efficient representations of tropospheric aerosol in climate studies. Estimates of aerosol radiative properties are provided for both total and anthropogenic aerosol in annual time steps from preindustrial times (i.e., starting with year 1860) well into the future (until the year 2100). Central to the aerosol climatology is the merging of monthly statistics of aerosol optical properties for current (year 2000) conditions. Hereby locally sparse but trusted high-quality data by ground-based sun-photometer networks are merged onto complete background maps defined by central data from global modeling with complex aerosol modules. This merging yields 0.13 for the global annual midvisible aerosol optical depth (AOD), with 0.07 attributed to aerosol sizes larger than 1 µm in diameter and 0.06 of attributed to aerosol sizes smaller than 1 µm in diameter. Hereby larger particles are less absorbing with a single scattering albedo (SSA) of 0.98 compared to 0.93 for smaller sizes. Simulation results of a global model are applied to prescribe the vertical distribution and to estimate anthropogenic contributions to the smaller size AOD as a function of time, with a 0.037 value for current conditions. In a demonstration application, the associated aerosol direct radiative effects are determined. For current conditions, total aerosol is estimated to reduce the combined shortwave and longwave net-flux balance at the top of the atmosphere by about -1.6 W/m2 from which -0.5 W/m2 (with

  5. Direct Measurement of Aerosol Absorption Using Photothermal Interferometry

    Science.gov (United States)

    Sedlacek, A. J.; Lee, J. A.

    2007-12-01

    Efforts to bound the contribution of light absorption in aerosol radiative forcing is still very much an active area of research in large part because aerosol extinction is dominated by light scattering. In response to this and other technical issues, the aerosol community has actively pursued the development of new instruments to measure aerosol absorption (e.g., photoacoustic spectroscopy (PAS) and multi-angle absorption photometer (MAAP)). In this poster, we introduce the technique of photothermal interferometry (PTI), which combines the direct measurement capabilities of photothermal spectroscopy (PTS) with high-sensitivity detection of the localized heating brought about by the PT process through interferometry. At its most fundamental level, the PTI technique measures the optical pathlength change that one arm of an interferometer (referred to as the 'probe' arm) experiences relative to the other arm of the interferometer (called the 'reference' arm). When the two arms are recombined at a beamsplitter, an interference pattern is created. If the optical pathlength in one arm of the interferometer changes, a commensurate shift in the interference pattern will take place. For the specific application of measuring light absorption, the heating of air surrounding the light- absorbing aerosol following laser illumination induces the optical pathlength change. This localized heating creates a refractive index gradient causing the probe arm of the interferometer to take a slightly different optical pathlength relative to the unperturbed reference arm. This effect is analogous to solar heating of a road causing mirages. As discussed above, this altered optical pathlength results in a shift in the interference pattern that is then detected as a change in the signal intensity by a single element detector. The current optical arrangement utilizes a folded Jamin interferometer design (Sedlacek, 2006) that provides a platform that is robust with respect to sensitivity

  6. 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.

  7. Argon offline-AMS source apportionment of organic aerosol over yearly cycles for an urban, rural, and marine site in northern Europe

    OpenAIRE

    Bozzetti, Carlo; Sosedova, Yuliya; Xiao, Mao; Daellenbach, Kaspar R.; Ulevicius, Vidmantas; Dudoitis, Vadimas; Mordas, Genrik; Byčenkienė, Steigvilė; Plauškaitė, Kristina; Vlachou, Athanasia; Golly, Benjamin; Chazeau, Benjamin; Besombes, Jean-Luc; Baltensperger, Urs; Jaffrezo, Jean-Luc

    2017-01-01

    The widespread use of Aerodyne aerosol mass spectrometers (AMS) has greatly improved real-time organic aerosol (OA) monitoring, providing mass spectra that contain sufficient information for source apportionment. However, AMS field deployments remain expensive and demanding, limiting the acquisition of long-term datasets at many sampling sites. The offline application of aerosol mass spectrometry entailing the analysis of nebulized water extracted filter samples (offline-AMS...

  8. Aerosol and monsoon climate interactions over Asia

    Science.gov (United States)

    Li, Zhanqing; Lau, W. K.-M.; Ramanathan, V.; Wu, G.; Ding, Y.; Manoj, M. G.; Liu, J.; Qian, Y.; Li, J.; Zhou, T.; Fan, J.; Rosenfeld, D.; Ming, Y.; Wang, Y.; Huang, J.; Wang, B.; Xu, X.; Lee, S.-S.; Cribb, M.; Zhang, F.; Yang, X.; Zhao, C.; Takemura, T.; Wang, K.; Xia, X.; Yin, Y.; Zhang, H.; Guo, J.; Zhai, P. M.; Sugimoto, N.; Babu, S. S.; Brasseur, G. P.

    2016-12-01

    The increasing severity of droughts/floods and worsening air quality from increasing aerosols in Asia monsoon regions are the two gravest threats facing over 60% of the world population living in Asian monsoon regions. These dual threats have fueled a large body of research in the last decade on the roles of aerosols in impacting Asian monsoon weather and climate. This paper provides a comprehensive review of studies on Asian aerosols, monsoons, and their interactions. The Asian monsoon region is a primary source of emissions of diverse species of aerosols from both anthropogenic and natural origins. The distributions of aerosol loading are strongly influenced by distinct weather and climatic regimes, which are, in turn, modulated by aerosol effects. On a continental scale, aerosols reduce surface insolation and weaken the land-ocean thermal contrast, thus inhibiting the development of monsoons. Locally, aerosol radiative effects alter the thermodynamic stability and convective potential of the lower atmosphere leading to reduced temperatures, increased atmospheric stability, and weakened wind and atmospheric circulations. The atmospheric thermodynamic state, which determines the formation of clouds, convection, and precipitation, may also be altered by aerosols serving as cloud condensation nuclei or ice nuclei. Absorbing aerosols such as black carbon and desert dust in Asian monsoon regions may also induce dynamical feedback processes, leading to a strengthening of the early monsoon and affecting the subsequent evolution of the monsoon. Many mechanisms have been put forth regarding how aerosols modulate the amplitude, frequency, intensity, and phase of different monsoon climate variables. A wide range of theoretical, observational, and modeling findings on the Asian monsoon, aerosols, and their interactions are synthesized. A new paradigm is proposed on investigating aerosol-monsoon interactions, in which natural aerosols such as desert dust, black carbon from

  9. 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.

  10. Marine Aerosols: Hygroscopocity and Aerosol-Cloud Relationships

    Science.gov (United States)

    2012-09-30

    large eddy simulation (LES) and field measurements, the latter including Twin Otter missions such as MASE I and MASE II and those involving other...continuous spectral aerosol-droplet microphysics model is presented and implemented into the Weather Research and Forecasting (WRF) model for large- eddy ...Dey, A. Sorooshian, F. J. Brechtel, Z. Wang, A. Metcalf , M. Coggon, J. Mulmenstadt, L. M. Russell, H. H. Jonsson, and J. H. Seinfeld, Atmos. Meas

  11. María Teresa Calderón y Clément Thibaud. La majestad de los pueblos en la Nueva Granada y Venezuela, 1780-1832

    Directory of Open Access Journals (Sweden)

    Daniel Gutiérrez Ardila

    2012-11-01

    Full Text Available Normal 0 21 false false false ES-CO X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} El libro de María Teresa Calderón y Clément Thibaud intenta responder a una cuestión que no por ser formulada en términos sencillos tiene un fácil desarrollo: si existe una historia del Estado, debe existir una historia de la soberanía. En otros términos, si resulta del todo inconveniente proyectar el Estado weberiano sobre el pasado como una entelequia ahistórica, no puede sostenerse sin graves consecuencias (el relato de la decepción democrática que hay un tránsito inmediato de la soberanía del rey a la soberanía de la nación o del pueblo. Entre ambos paradigmas se desliza un periodo híbrido en el que la majestad real contribuye a la comprensión y a la elaboración por parte de los revolucionarios de la nueva baza de la legitimidad.

  12. Do atmospheric aerosols form glasses?

    Science.gov (United States)

    Zobrist, B.; Marcolli, C.; Pedernera, D. A.; Koop, T.

    2008-09-01

    A new process is presented by which water soluble organics might influence ice nucleation, ice growth, chemical reactions and water uptake of aerosols in the upper troposphere: the formation of glassy aerosol particles. Glasses are disordered amorphous (non-crystalline) solids that form when a liquid is cooled without crystallization until the viscosity increases exponentially and molecular diffusion practically ceases. The glass transition temperatures, Tg, homogeneous ice nucleation temperatures, Thom, and ice melting temperatures, Tm, of various aqueous inorganic, organic and multi-component solutions are investigated with a differential scanning calorimeter. The investigated solutes are: various polyols, glucose, raffinose, levoglucosan, an aromatic compound, sulfuric acid, ammonium bisulfate and mixtures of dicarboxylic acids (M5), of dicarboxylic acids and ammonium sulfate (M5AS), of two polyols, of glucose and ammonium nitrate, and of raffinose and M5AS. The results indicate that aqueous solutions of the investigated inorganic solutes show Tg values that are too low to be of atmospheric importance. In contrast, aqueous organic and multi-component solutions readily form glasses at low but atmospherically relevant temperatures (≤230 K). To apply the laboratory data to the atmospheric situation, the measured phase transition temperatures were transformed from a concentration to a water activity scale by extrapolating water activities determined between 252 K and 313 K to lower temperatures. The obtained state diagrams reveal that the higher the molar mass of the aqueous organic or multi-component solutes, the higher Tg of their respective solutions at a given water activity. To a lesser extent, Tg also depends on the hydrophilicity of the organic solutes. Therefore, aerosol particles containing larger (≳150 g mol-1) and more hydrophobic organic molecules are more likely to form glasses at intermediate to high relative humidities in the upper troposphere

  13. Do atmospheric aerosols form glasses?

    Directory of Open Access Journals (Sweden)

    D. A. Pedernera

    2008-09-01

    Full Text Available A new process is presented by which water soluble organics might influence ice nucleation, ice growth, chemical reactions and water uptake of aerosols in the upper troposphere: the formation of glassy aerosol particles. Glasses are disordered amorphous (non-crystalline solids that form when a liquid is cooled without crystallization until the viscosity increases exponentially and molecular diffusion practically ceases. The glass transition temperatures, Tg, homogeneous ice nucleation temperatures, Thom, and ice melting temperatures, Tm, of various aqueous inorganic, organic and multi-component solutions are investigated with a differential scanning calorimeter. The investigated solutes are: various polyols, glucose, raffinose, levoglucosan, an aromatic compound, sulfuric acid, ammonium bisulfate and mixtures of dicarboxylic acids (M5, of dicarboxylic acids and ammonium sulfate (M5AS, of two polyols, of glucose and ammonium nitrate, and of raffinose and M5AS. The results indicate that aqueous solutions of the investigated inorganic solutes show Tg values that are too low to be of atmospheric importance. In contrast, aqueous organic and multi-component solutions readily form glasses at low but atmospherically relevant temperatures (≤230 K. To apply the laboratory data to the atmospheric situation, the measured phase transition temperatures were transformed from a concentration to a water activity scale by extrapolating water activities determined between 252 K and 313 K to lower temperatures. The obtained state diagrams reveal that the higher the molar mass of the aqueous organic or multi-component solutes, the higher Tg of their respective solutions at a given water activity. To a lesser extent, Tg also depends on the hydrophilicity of the organic solutes. Therefore, aerosol particles containing larger (≳150 g mol−1 and

  14. Do atmospheric aerosols form glasses?

    Directory of Open Access Journals (Sweden)

    B. Zobrist

    2008-05-01

    Full Text Available A new process is presented by which water-soluble organics might influence ice nucleation, ice growth, chemical reactions and water uptake of aerosols in the upper troposphere: the formation of glassy aerosol particles. Glasses are disordered amorphous (non-crystalline solids that form when a liquid is cooled without crystallization until the viscosity increases exponentially and molecular diffusion practically ceases. The glass transition temperatures, Tg, homogeneous ice nucleation temperatures, Thom, and ice melting temperatures, Tm, of various aqueous inorganic, organic and multi-component solutions are investigated with a differential scanning calorimeter. The investigated solutes are: various polyols, glucose, raffinose, levoglucosan, an aromatic compound, sulfuric acid, ammonium bisulphate and mixtures of dicarboxylic acids (M5, of dicarboxylic acids and ammonium sulphate (M5AS, of two polyols, of glucose and ammonium nitrate, and of raffinose and M5AS. The results indicate that aqueous solutions of the investigated inorganic solutes show Tg-values that are too low to be of atmospheric importance. In contrast, aqueous organic and multi-component solutions readily form glasses at low but atmospherically relevant temperatures (≤230 K. To apply the laboratory data to the atmospheric situation, the measured phase transition temperatures were transformed from a concentration to a water activity scale by extrapolating water activities determined between 252 K and 313 K to lower temperatures. The obtained state diagrams reveal that the higher the molar mass of the aqueous organic or multi-component solutes, the higher Tg of their respective solutions at a given water activity. To a lesser extent, Tg also depends on the hydrophilicity of the organic solutes. Therefore, aerosol particles containing larger and more hydrophobic organic

  15. Comparison of aerosol and bioaerosol collection on air filters.

    Science.gov (United States)

    Miaskiewicz-Peska, Ewa; Lebkowska, Maria

    2012-06-01

    Air filters efficiency is usually determined by non-biological test aerosols, such as potassium chloride particles, Arizona dust or di-ethyl-hexyl-sebacate (DEHS) oily liquid. This research was undertaken to asses, if application of non-biological aerosols reflects air filters capacity to collect particles of biological origin. The collection efficiency for non-biological aerosol was tested with the PALAS set and ISO Fine Test Dust. Flow rate during the filtration process was 720 l/h, and particles size ranged 0.246-17.165 μm. The upstream and downstream concentration of the aerosol was measured with a laser particle counter PCS-2010. Tested bioaerosol contained 4 bacterial strains of different shape and size: Micrococcus luteus,Micrococcus varians, Pseudomonas putida and Bacillus subtilis. Number of the biological particles was estimated with a culture-based method. Results obtained with bioaerosol did not confirmed 100% filters efficiency noted for the mineral test dust of the same aerodynamic diameter. Maximum efficiency tested with bacterial cells was 99.8%. Additionally, cells reemission from filters into air was also studied. Bioaerosol contained 3 bacterial strains: Micrococcus varians, Pseudomonas putida and Bacillus subtilis. It was proved that the highest intensity of the reemission process was during the first 5 min. and reached maximum 0.63% of total number of bacteria retained in filters. Spherical cells adhered stronger to the filter fibres than cylindrical ones. It was concluded that non-biological aerosol containing particles of the same shape and surface characteristics (like DEHS spherical particles) can not give representative results for all particles present in the filtered air.

  16. Field and Laboratory Studies of Atmospheric Organic Aerosol

    Science.gov (United States)

    Coggon, Matthew Mitchell

    This thesis is the culmination of field and laboratory studies aimed at assessing processes that affect the composition and distribution of atmospheric organic aerosol. An emphasis is placed on measurements conducted using compact and high-resolution Aerodyne Aerosol Mass Spectrometers (AMS). The first three chapters summarize results from aircraft campaigns designed to evaluate anthropogenic and biogenic impacts on marine aerosol and clouds off the coast of California. Subsequent chapters describe laboratory studies intended to evaluate gas and particle-phase mechanisms of organic aerosol oxidation. The 2013 Nucleation in California Experiment (NiCE) was a campaign designed to study environments impacted by nucleated and/or freshly formed aerosol particles. Terrestrial biogenic aerosol with > 85% organic mass was observed to reside in the free troposphere above marine stratocumulus. This biogenic organic aerosol (BOA) originated from the Northwestern United States and was transported to the marine atmosphere during periodic cloud-clearing events. Spectra recorded by a cloud condensation nuclei counter demonstrated that BOA is CCN active. BOA enhancements at latitudes north of San Francisco, CA coincided with enhanced cloud water concentrations of organic species such as acetate and formate. Airborne measurements conducted during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE) were aimed at evaluating the contribution of ship emissions to the properties of marine aerosol and clouds off the coast of central California. In one study, analysis of organic aerosol mass spectra during periods of enhanced shipping activity yielded unique tracers indicative of cloud-processed ship emissions (m/z 42 and 99). The variation of their organic fraction (f42 and f 99) was found to coincide with periods of heavy (f 42 > 0.15; f99 > 0.04), moderate (0.05 < f42 < 0.15; 0.01 < f99 < 0.04), and negligible (f42 < 0.05; f99 < 0.01) ship influence. Application of

  17. 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

  18. MATRIX-VBS: implementing an evolving organic aerosol volatility in an aerosol microphysics model

    OpenAIRE

    Gao, Chloe Y.; Tsigaridis, Kostas; Bauer, Susanne E.

    2016-01-01

    We have implemented an existing aerosol microphysics scheme into a box model framework and extended it to represent gas-particle partitioning and chemical ageing of semi-volatile organic aerosols. We then applied this new research tool to investigate the effects of semi-volatile organic species on the growth, composition and mixing state of aerosol particles in case studies representing several different environments. The volatility-basis set (VBS) framework is implemented into the aerosol mi...

  19. First Evaluation of the CCAM Aerosol Simulation over Africa: Implications for Regional Climate Modeling

    Science.gov (United States)

    Horowitz, H.; Garland, R. M.; Thatcher, M. J.; Naidoo, M.; van der Merwe, J.; Landman, W.; Engelbrecht, F.

    2015-12-01

    regional climate modeling and the potential impact on climate predictions, and is the first large scale climate model-measurement verification of aerosols over Africa that we are aware of. CCAM is widely used for regional climate modeling applications, and we also discuss further improvements to the aerosol parameterizations based on our results.

  20. Requirements For Lidar Aerosol and Ozone Measurements

    Science.gov (United States)

    Frey, S.; Woeste, L.

    borne and ground based Aerosol and Ozone measure- ments, to give an idea, what kind of technique and input data is required to get reliable results. As an example for an application I oppose experimentally retrieved planetary boundary layer height and ozone concentrations with results of a chemical dispersion model for the region Berlin/Brandenburg. One mayor task for the future is to apply the advanced laser remote sensing techniques on all continents at as much location as possible, to get a first impression about the variability and correlation of optical parameters of the atmosphere and to gather databases, which allow to find the right input values for evaluation of space borne data.

  1. Aerosol classification by airborne high spectral resolution lidar observations

    Science.gov (United States)

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

    2013-03-01

    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 mixture, 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 supported by backward trajectory analysis and validated with in-situ measurements. Our results demonstrate that the developed aerosol mask is capable to identify complex stratifications with different aerosol types throughout the atmosphere.

  2. Aerosols in and Above the Bornean Rainforest

    OpenAIRE

    Robinson, Niall Hamilton

    2011-01-01

    Atmospheric aerosols affect climate directly by scattering and absorbing solar radiation, and indirectly by affecting the albedo and lifetime of clouds through their role as cloud condensation nuclei. Aerosol sources, and the processes that govern their evolution in the atmosphere are not well understood, making the aerosol effects a significant source of uncertainty in future climate predictions. The tropics experience a large solar flux meaning that any radiative forcing in this region is p...

  3. The European aerosol budget in 2006

    Directory of Open Access Journals (Sweden)

    J. M. J. Aan de Brugh

    2011-02-01

    Full Text Available This paper presents the aerosol budget over Europe in 2006 calculated with the global transport model TM5 coupled to the size-resolved aerosol module M7. Comparison with ground observations indicates that the model reproduces the observed concentrations quite well with an expected slight underestimation of PM10 due to missing emissions (e.g. resuspension. We model that a little less than half of the anthropogenic aerosols emitted in Europe are exported and the rest is removed by deposition. The anthropogenic aerosols are removed mostly by rain (95% and only 5% is removed by dry deposition. For the larger natural aerosols, especially sea salt, a larger fraction is removed by dry processes (sea salt: 70%, mineral dust: 35%. We model transport of aerosols in the jet stream in the higher atmosphere and an import of Sahara dust from the south at high altitudes. Comparison with optical measurements shows that the model reproduces the Ångström parameter very well, which indicates a correct simulation of the aerosol size distribution. However, we underestimate the aerosol optical depth. Because the surface concentrations are close to the observations, the shortage of aerosol in the model is probably at higher altitudes. We show that the discrepancies are mainly caused by an overestimation of wet-removal rates. To match the observations, the wet-removal rates have to be scaled down by a factor of about 5. In that case the modelled ground-level concentrations of sulphate and sea salt increase by 50% (which deteriorates the match, while other components stay roughly the same. Finally, it is shown that in particular events, improved fire emission estimates may significantly improve the ability of the model to simulate the aerosol optical depth. We stress that discrepancies in aerosol models can be adequately analysed if all models would provide (regional aerosol budgets, as presented in the current study.

  4. Confined Aerosol Jet in Fiber Classification and Dustiness Measurement

    Science.gov (United States)

    Dubey, Prahit

    The focus of this dissertation is the numerical analysis of confined aerosol jets used in fiber classification and dustiness measurement. Of relevance to the present work are two devices, namely, the Baron Fiber Classifier (BFC), and the Venturi Dustiness Tester (VDT). The BFC is a device used to length-separate fibers, important for toxicological research. The Flow Combination Section (FCS) of this device consists of an upstream region, where an aerosol of uncharged fibers is introduced in the form of an annular jet, in-between two sheath flows. Length-separation occurs by dielectrophoresis, downstream of the FCS in the Fiber Classification Section (FClS). In its standard operation, BFC processes only small quantities of fibers. In order to increase its throughput, higher aerosol flow rates must be considered. The goal of the present investigation is to understand the interaction of sheath and aerosol flows inside the FCS, and to identify possible limits to increasing aerosol flow rates using Computational Fluid Dynamics (CFD). Simulations involve solution of Navier-Stokes equations for axisymmetric and 3D models of the FCS for six different flow rates, and a pure aerodynamic treatment of the aerosol jet. The results show that the geometry of the FCS, and the two sheath flows, are successful in preventing the emergence of vortices in the FCS for aerosol-to-sheath flow inlet velocity ratios below ≈ 50. For larger aerosol-to-sheath flow inlet velocity ratios, two vortices are formed, one near the inner cylinder and one near the outer cylinder. The VDT is a novel device for measuring the dustiness of powders, relevant for dust management and controlling hazardous exposure. It uses just 10 mg of the test powder for its operation, during which the powder is aerosolized and turbulently dispersed (Re = 19,900) for 1.5s into a 5.7 liter chamber; the aerosol is then gently sampled (Re = 2050) for 240s through two filters located at the chamber top. Pump-driven suction at

  5. Infrared Absorption by Atmospheric Aerosols in Mexico City during MILAGRO.

    Science.gov (United States)

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

    2007-12-01

    found as colloidal materials in surface and groundwaters (4). Examples of the IR spectra obtained and variance as a function of time at the two sites will be presented. The spectra are taken in Kubelka - Munk format, which also allows the infrared absorption strengths to be evaluated as function of wavelength. The wavelength dependence of the aerosol complex refractive index (m = n + ik) in the infrared spectral region is determined by application of the Kramers Kronig function. The importance of the aerosol absorption in the infrared spectral region to radiative forcing will be discussed. 1. N.A. Marley, J.S. Gaffney, and M.M. Cunningham,Environ. Sci. Technol. 27 2864-2869 (1993). 2. N.A. Marley, J.S. Gaffney, and M.M. Cunningham, Spectroscopy 7 44-53 (1992). 3. J.S. Gaffney and N.A. Marley, Atmospheric Environment, New Directions contribution, 32, 2873-2874 (1998). 4. N.A. Marley, J.S. Gaffney, and K.A. Orlandini, Chapter 7 in Humic/Fulvic Acids and Organic Colloidal Materials in the Environment, ACS Symposium Series 651, American Chemical Society, Washington, D.C., pp. 96-107, 1996. This work was performed as part of the Department of Energy's Megacity Aerosol Experiment - Mexico City (MAX- Mex) under the support of the Atmospheric Science Program. This research was supported by the Office of Science (BER), U.S. Department of Energy, Grant No. DE-FG02-07ER64328.

  6. Large differences in aerosol optical properties over the north-west Atlantic Ocean during the TCAP field campaign

    Science.gov (United States)

    Chand, D.; Berg, L. K.; Comstock, J. M.; Fast, J. D.; Flynn, C. J.; Hubbe, J. M.; Kassianov, E.; Mei, F.; Pekour, M. S.; Schmid, B.; Sedlacek, A. J., III; Tomlinson, J. M.; Shilling, J. E.; Wilson, J. M.; Zelenyuk, A.; Berkowitz, C. M.

    2014-12-01

    Aerosol radiative forcing is an important parameter in the Earth's radiation budget and can be an important driver of atmospheric circulation and the hydrological cycle. Accurate estimation of aerosol radiative forcing requires measurement of both the extensive and intensive optical properties of aerosols. While the intensive optical properties are independent of aerosol mass or number, they are critical inputs when calculating radiative forcing with applications to climate research, satellite remote sensing and model validations. The key aerosol intensive properties that need to be evaluated include single scattering albedo (SSA), the angstrom exponent, the asymmetry parameter, the radiative forcing efficiency, and the hygroscopic scattering factor. We report here on values of these variables over the Cape Cod and nearby northwest Atlantic Ocean during the Two Column Aerosol Project (TCAP). The average SSA shows a distinct profile having higher SSA values below the top of well-mixed residual layer (RL) and lower SSA above it. Aerosol in the free troposphere (FT) were found to have less spectral dependence in their optical properties, lower back scatter fraction and higher hygroscopic growth relative to aerosols found in the RL. Analysis of individual particle composition suggests that that ratio of aged to fresh aerosol numbers in the FT is 70% higher compared to aerosols measured in the RL, and that smoke from biomass burning contributed ~10% to this number. Single particle analysis also reveals that the fraction and variability of coated black carbon (BC) aerosol is higher in the FT relative to that measured in the residual layer. The daily radiative forcing efficiency of these aerosols in the FT is factor 2 higher than below RL. Seven years (2007-2013) of CALIPSO satellite observations show that the mean altitude of the top of smoke layers (~3.3 km) consistent with these in situ observations from TCAP. Overall, the long term CALIPSO observations characterizes

  7. Enhancement of aerosol characterization using synergy of lidar and sun - photometer coincident observations: the GARRLiC algorithm

    Science.gov (United States)

    Lopatin, A.; Dubovik, O.; Chaikovsky, A.; Goloub, Ph.; Lapyonok, T.; Tanré, D.; Litvinov, P.

    2013-03-01

    concentration but it also differentiates between the contributions of fine and coarse modes of aerosol. The detailed microphysical properties are assumed height independent and different for each mode and expected to be derived as a part of the retrieval. Thus, the GARRLiC inversion algorithm retrieves vertical distribution of both fine and coarse aerosol concentrations as well as the size distribution, complex refractive index and single scattering albedo for each mode. The potential and limitations of the method are demonstrated by the series of sensitivity tests. The practical outcome of the approach is illustrated by applications of the algorithm to the real lidar and radiometer observations obtained over selected AERONET site.

  8. 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

  9. 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.

  10. 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...

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    M. J. M. Penning de Vries

    2015-09-01

    Full Text Available 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

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

    Directory of Open Access Journals (Sweden)

    M. J. M. Penning de Vries

    2015-05-01

    Full Text Available Detecting the optical properties of aerosols using passive satellite-borne measurements alone is a difficult task due to the broad-band 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

  14. Significant atmospheric aerosol pollution caused by world food cultivation

    Science.gov (United States)

    Bauer, Susanne E.; Tsigaridis, Kostas; Miller, Ron

    2016-05-01

    Particulate matter is a major concern for public health, causing cancer and cardiopulmonary mortality. Therefore, governments in most industrialized countries monitor and set limits for particulate matter. To assist policy makers, it is important to connect the chemical composition and severity of particulate pollution to its sources. Here we show how agricultural practices, livestock production, and the use of nitrogen fertilizers impact near-surface air quality. In many densely populated areas, aerosols formed from gases that are released by fertilizer application and animal husbandry dominate over the combined contributions from all other anthropogenic pollution. Here we test reduction scenarios of combustion-based and agricultural emissions that could lower air pollution. For a future scenario, we find opposite trends, decreasing nitrate aerosol formation near the surface while total tropospheric loads increase. This suggests that food production could be increased to match the growing global population without sacrificing air quality if combustion emission is decreased.

  15. Significant Atmospheric Aerosol Pollution Caused by World Food Cultivation

    Science.gov (United States)

    Bauer, Susanne E.; Tsigaridis, Kostas; Miller, Ron

    2016-01-01

    Particulate matter is a major concern for public health, causing cancer and cardiopulmonary mortality. Therefore, governments in most industrialized countries monitor and set limits for particulate matter. To assist policy makers, it is important to connect the chemical composition and severity of particulate pollution to its sources. Here we show how agricultural practices, livestock production, and the use of nitrogen fertilizers impact near-surface air quality. In many densely populated areas, aerosols formed from gases that are released by fertilizer application and animal husbandry dominate over the combined contributions from all other anthropogenic pollution. Here we test reduction scenarios of combustion-based and agricultural emissions that could lower air pollution. For a future scenario, we find opposite trends, decreasing nitrate aerosol formation near the surface while total tropospheric loads increase. This suggests that food production could be increased to match the growing global population without sacrificing air quality if combustion emission is decreased.

  16. Estimating aerosol emissions by assimilating observed aerosol optical depth in a global aerosol model

    Directory of Open Access Journals (Sweden)

    N. Huneeus

    2012-01-01

    Full Text Available This study estimates the emission fluxes of a range of aerosol species and aerosol precursor at the global scale. These fluxes are estimated by assimilating daily total and fine mode aerosol optical depth (AOD at 550 nm from the Moderate Resolution Imaging Spectroradiometer (MODIS into a global aerosol model of intermediate complexity. Monthly emissions are fitted homogenously for each species over a set of predefined regions. The performance of the assimilation is evaluated by comparing the AOD after assimilation against the MODIS observations and against independent observations. The system is effective in forcing the model towards the observations, for both total and fine mode AOD. Significant improvements for the root mean square error and correlation coefficient against both the assimilated and independent datasets are observed as well as a significant decrease in the mean bias against the assimilated observations. The assimilation is more efficient over land than over ocean. The impact of the assimilation of fine mode AOD over ocean demonstrates potential for further improvement by including fine mode AOD observations over continents. The Angström exponent is also improved in African, European and dusty stations. The estimated emission flux for black carbon is 14.5 Tg yr−1, 119 Tg yr−1 for organic matter, 17 Pg yr−1 for sea salt, 82.7 TgS yr−1 for SO2 and 1383 Tg yr−1 for desert dust. They represent a difference of +45%, +40%, +26%, +13% and −39% respectively, with respect to the a priori values. The initial errors attributed to the emission fluxes are reduced for all estimated species.

  17. Estimating aerosol emissions by assimilating observed aerosol optical depth in a global aerosol model

    Directory of Open Access Journals (Sweden)

    N. Huneeus

    2012-05-01

    Full Text Available This study estimates the emission fluxes of a range of aerosol species and one aerosol precursor at the global scale. These fluxes are estimated by assimilating daily total and fine mode aerosol optical depth (AOD at 550 nm from the Moderate Resolution Imaging Spectroradiometer (MODIS into a global aerosol model of intermediate complexity. Monthly emissions are fitted homogenously for each species over a set of predefined regions. The performance of the assimilation is evaluated by comparing the AOD after assimilation against the MODIS observations and against independent observations. The system is effective in forcing the model towards the observations, for both total and fine mode AOD. Significant improvements for the root mean square error and correlation coefficient against both the assimilated and independent datasets are observed as well as a significant decrease in the mean bias against the assimilated observations. These improvements are larger over land than over ocean. The impact of the assimilation of fine mode AOD over ocean demonstrates potential for further improvement by including fine mode AOD observations over continents. The Angström exponent is also improved in African, European and dusty stations. The estimated emission flux for black carbon is 15 Tg yr−1, 119 Tg yr−1 for particulate organic matter, 17 Pg yr−1 for sea salt, 83 TgS yr−1 for SO2 and 1383 Tg yr−1 for desert dust. They represent a difference of +45 %, +40 %, +26 %, +13 % and −39 % respectively, with respect to the a priori values. The initial errors attributed to the emission fluxes are reduced for all estimated species.

  18. 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.

  19. 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.

  20. Elevated aerosols and role of circulation parameters in aerosol vertical distribution

    Science.gov (United States)

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

    2016-01-01

    The study examines aerosol loading in different vertical layers of the atmosphere and explores the role of atmospheric circulation parameters in vertical distribution of aerosols and in its seasonal variability. Aerosol vertical distribution over the globe is examined, using long term satellite observations, by considering aerosol loading in different layers of atmosphere upto ∼6 km altitudes from surface and fractional contribution of each of these layers to total columnar aerosol loading. Aerosols are observed residing close to the surface in most of the oceanic environments, except over certain regions which are in the close proximity of continents where upper level winds are conducive for long range aerosol transport. In contrast, considerable vertical spread in aerosol distribution with strong seasonal variability, minimum occurring in winter months and maximum in summer, is observed over the continental regions. Vertical spread in aerosol distribution is observed highest over north eastern and north western parts of Africa during northern hemispheric summer, when the convection activity peaks over these regions due to large solar insolation and associated surface heating. Seasonal variation of aerosol vertical spread over both of these regions is observed in phase with variation in atmospheric convergence and vorticity. During summer months, when the aerosol vertical spread is highest, strong surface level convergence and associated cyclonic vorticity is observed along with an upper level (700-600 hPa) divergence. The surface level convergence and upper level divergence together induce an upward flow of air which carries aerosols from ground to higher altitudes. This mechanism of aerosol vertical transport is further corroborated through the correlation and regression relations of surface convergence/vorticity with aerosol loading above different elevations and hence the study reveals role of circulation parameters in aerosol vertical distribution.

  1. Efficacy of an Esfenvalerate plus Methoprene Aerosol for the Control of Eggs and Fifth Instars of the Plodia interpunctella (Lepidoptera: Pyralidae)

    Science.gov (United States)

    Aerosol insecticides may provide an alternative to fumigants for control of the Indianmeal moth, Plodia interpunctella (Hübner), a major insect pest of stored processed food. In this study, eggs and larvae (5th instars) of P. interpunctella were exposed to aerosol applications of the pyrethroid esf...

  2. The Cloud-Aerosol Transport System (CATS): A New Lidar for Aerosol and Cloud Profiling from the International Space Station

    Science.gov (United States)

    Welton, Ellsworth J.; McGill, Mathew J.; Yorks. John E.; Hlavka, Dennis L.; Hart, William D.; Palm, Stephen P.; Colarco, Peter R.

    2012-01-01

    Spaceborne lidar profiling of aerosol and cloud layers has been successfully implemented during a number of prior missions, including LITE, ICESat, and CALIPSO. Each successive mission has added increased capability and further expanded the role of these unique measurements in wide variety of applications ranging from climate, to air quality, to special event monitoring (ie, volcanic plumes). Many researchers have come to rely on the availability of profile data from CALIPSO, especially data coincident with measurements from other A-Train sensors. The CALIOP lidar on CALIPSO continues to operate well as it enters its fifth year of operations. However, active instruments have more limited lifetimes than their passive counterparts, and we are faced with a potential gap in lidar profiling from space if the CALIOP lidar fails before a new mission is operational. The ATLID lidar on EarthCARE is not expected to launch until 2015 or later, and the lidar component of NASA's proposed Aerosols, Clouds, and Ecosystems (ACE) mission would not be until after 2020. Here we present a new aerosol and cloud lidar that was recently selected to provide profiling data from the International Space Station (ISS) starting in 2013. The Cloud-Aerosol Transport System (CATS) is a three wavelength (1064,532,355 nm) elastic backscatter lidar with HSRL capability at 532 nm. Depolarization measurements will be made at all wavelengths. The primary objective of CATS is to continue the CALIPSO aerosol and cloud profile data record, ideally with overlap between both missions and EarthCARE. In addition, the near real time (NRT) data capability ofthe ISS will enable CATS to support operational applications such as aerosol and air quality forecasting and special event monitoring. The HSRL channel will provide a demonstration of technology and a data testbed for direct extinction retrievals in support of ACE mission development. An overview of the instrument and mission will be provided, along with a

  3. 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.

  4. Estimation of aerosol type from airborne hyperspectral data: a new technique designed for industrial plume characterization

    Science.gov (United States)

    Deschamps, A.; Marion, R.; Foucher, P.-Y.; Briottet, X.

    2012-11-01

    The determination of the aerosol type in a plume from remotely sensed data without any a priori knowledge is a challenging task. If several methods have already been developed to characterize the aerosols from multi or hyperspectral data, they are not suited for industrial particles, which have specific physical and optical properties, changing quickly and in a complex way with the distance from the source emission. From radiative transfer equations, we have developed an algorithm, based on a Look-Up Table approach, enabling the determination of the type of this kind of particles from hyperspectral data. It consists in the selection of pixels pairs, located at the transitions between two kinds of grounds (or between an illuminated and a shadow area), then in the comparison between normalized estimated Aerosol Optical Thicknesses (AOTs) and pre-calculated AOTs. The application of this algorithm to simulated data leads to encouraging results: the selection of only six pixels pairs allows the algorithm to differentiate aerosols emitted by a metallurgical plant from biomass burning particles, urban aerosols and particles from an oil depot explosion, regardless the size and the aerosol concentration. The algorithm performances are better for a relatively high AOT but the single scattering approximation does not enable the characterization of thick plumes (AOT above 2.0). However, the choice of transitions (type of grounds) does not seem to significantly affect the results.

  5. Real-time measurement of aerosol particle concentration at high temperatures; Hiukkaspitoisuuden reaaliaikainen mittaaminen korkeassa laempoetilassa

    Energy Technology Data Exchange (ETDEWEB)

    Keskinen, J.; Hautanen, J.; Laitinen, A. [Tampere Univ. of Technology (Finland). Physics

    1997-10-01

    The aim of this project is to develop a new method for continuous aerosol particle concentration measurement at elevated temperatures (up to 800-1000 deg C). The measured property of the aerosol particles is the so called Fuchs surface area. This quantity is relevant for diffusion limited mass transfer to particles. The principle of the method is as follows. First, aerosol particles are charged electrically by diffusion charging process. The charging takes place at high temperature. After the charging, aerosol is diluted and cooled. Finally, aerosol particles are collected and the total charge carried by the aerosol particles is measured. Particle collection and charge measurement take place at low temperature. Benefits of this measurement method are: particles are charged in-situ, charge of the particles is not affected by the temperature and pressure changes after sampling, particle collection and charge measurement are carried out outside the process conditions, and the measured quantity is well defined. The results of this study can be used when the formation of the fly ash particles is studied. Another field of applications is the study and the development of gasification processes. Possibly, the method can also be used for the monitoring the operation of the high temperature particle collection devices. (orig.)

  6. Spectro-microscopy of Ambient Aerosol Particles: Observational Constraints on Mixing State Parameterization

    Science.gov (United States)

    OBrien, R. E.; Wang, B.; Laskin, A.; West, M.; Riemer, N. S.; Gilles, M. K.; Moffet, R.

    2014-12-01

    Individual aerosol particles are often mixtures of multiple components such as inorganic salts, soot or elemental carbon, and organic molecules. The amounts of the different components in each particle and the particle morphologies will impact the CCN activity and the radiative properties of the aerosol population. A recent parameterization of the mixing state developed by Nicole Riemer and Matthew West provides a clear transition between ambient measurements of aerosol components and particle mixing states employed in climate models. Single particle spectro-microscopy techniques including scanning transmission x-ray microscopy/near-edge x-ray absorption fine structure spectroscopy (STXM/NEXAFS) and computer controlled scanning electron microscopy/energy dispersive x-ray spectroscopy (CCSEM/EDX) are used to measure the composition of aerosol particles from the CARES campaign at both T0 and T1. Here, we present results from the application of the per particle composition to a parameterization of the mixing state and provide constraints on the mixing state of ambient aerosol particles. The two microscopy techniques yield complementary information on the mixing state of the aerosol populations; STXM/NEXAFS provides information on the mixing state of the organic fraction while CCSEM/EDX provides information on the inorganic fraction.

  7. 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.

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

    Science.gov (United States)

    Wahab, A. M.; Sarker, M. L. R.

    2014-02-01

    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.

  9. Persistent improvement of gas exchange and lung mechanics by aerosolized perfluorocarbon.

    Science.gov (United States)

    Kandler, M A; von der Hardt, K; Schoof, E; Dötsch, J; Rascher, W

    2001-07-01

    The effect of aerosolized perfluorocarbon (PFC) (FC77) on pulmonary gas exchange and lung mechanics was studied in a surfactant depleted piglet model. Sixty minutes after induction of lung injury by bronchoalveolar lavage, 20 piglets were randomized to receive aerosolized PFC (Aerosol-PFC, 10 ml/kg/h, n = 5), partial liquid ventilation (PLV) at FRC capacity volume (FRC-PLV, 30 ml/kg, n = 5) or low volume (LV-PLV, 10 ml/kg/h, n = 5), or intermittent mandatory ventilation (IMV) (Control, n = 5). After 2 h, perfluorocarbon application was stopped and IMV was continued for 6 h. Sixty minutes after the onset of therapy, PaO2 was significantly higher and PaCO2 was significantly lower in the Aerosol-PFC and the FRC-PLV groups than in the LV-PLV and the Control groups; p Aerosol-PFC group: 406.4 +/- 26.9 mm Hg, FRC-PLV: 217.3 +/- 50.5 mm Hg, LV-PLV: 96.3 +/- 18.9 mm Hg, Control: 67.6 +/- 8.4 mm Hg; p Aerosol-PFC group: 24.2 +/- 1.7 mm Hg, FRC-PLV: 35.9 +/- 2.8 mm Hg, LV-PLV: 56.7 +/- 12.4 mm Hg, Control: 60.6 +/- 5.1 mm Hg; p Aerosol-PFC group; p Aerosolized perfluorocarbon improved pulmonary gas exchange and lung mechanics as effectively as PLV did in surfactant-depleted piglets, and the improvement was sustained longer.

  10. Recovery of surface reflectance spectra and evaluation of the optical depth of aerosols in the near-IR using a Monte-Carlo approach: Application to the OMEGA observations of high latitude regions of Mars

    CERN Document Server

    Vincendon, Mathieu; Poulet, François; Bibring, Jean-Pierre; Gondet, Brigitte; 10.1029/2006JE002845

    2011-01-01

    We present a model of radiative transfer through atmospheric particles based on Monte Carlo methods. This model can be used to analyze and remove the contribution of aerosols in remote sensing observations. We have developed a method to quantify the contribution of atmospheric dust in near-IR spectra of the Martian surface obtained by the OMEGA imaging spectrometer on board Mars Express. Using observations in the nadir pointing mode with significant differences in solar incidence angles, we can infer the optical depth of atmospheric dust, and we can retrieve the surface reflectance spectra free of aerosol contribution. Martian airborne dust properties are discussed and constrained from previous studies and OMEGA data. We have tested our method on a region at 90{\\deg}E and 77{\\deg}N extensively covered by OMEGA, where significant variations of the albedo of ice patches in the visible have been reported. The consistency between reflectance spectra of ice-covered and ice-free regions recovered at different incid...

  11. 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.

  12. Aerosol MALDI mass spectrometry for bioaerosol analysis

    NARCIS (Netherlands)

    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

  13. 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.

  14. The European aerosol budget in 2006

    NARCIS (Netherlands)

    Aan de Brugh, J.M.J.; Schaap, M.; Vignati, E.; Dentener, F.J.; Kahnert, M.; Sofiev, M.A.; Huijnen, V.; Krol, M.C.

    2011-01-01

    This paper presents the aerosol budget over Europe in 2006 calculated with the global transport model TM5 coupled to the size-resolved aerosol module M7. Comparison with ground observations indicates that the model reproduces the observed concentrations quite well with an expected slight underestima

  15. Inversion Techniques for Retrieving Detailed Aerosol Properties from Remote Sensing Observations: Achievements and Perspectives

    Science.gov (United States)

    Dubovik, O.

    2010-12-01

    applications. Specifically, the retrieval of detailed information about aerosol particle sizes, shape, absorption and composition (refractive index) from the observations by sun/sky-scanning radiometers has been developed and employed by worldwide AERONET network of ground-based radiometers. One of first retrievals of global aerosol emission sources from MODIS satellite observations have been suggested and realized using the same concept. Finally, the most recent results show a high potential of applying the methodology for deriving aerosol properties over bright land surfaces from POLDER multi-angle spectral polarimetric satellite observations using a new approach of simultaneous inversion of large groups of satellite pixels.

  16. Organic Composition and Morphology of Sea Spray Aerosols as a Function of Biological Life during IMPACTS

    Science.gov (United States)

    Pham, D.; Moffet, R.; Fraund, M. W.; O'Brien, R.; Laskina, O.; Prather, K. A.; Grassian, V. H.; Beall, C.; Wang, X.; Forestieri, S.; Cappa, C. D.

    2015-12-01

    Aerosols influence climate by directly reflecting or absorbing sunlight, or indirectly by affecting clouds. A major source of aerosols is from oceanic wave breaking. Due to their complexity, the effects of marine aerosol on climate are uncertain. To provide more detailed measurements of the chemical composition of marine aerosols, Scanning Transmission X-Ray Microscopy coupled with Near Edge X-Ray Absorption Fine Structure (SXTM-NEXAFS) was used to give spatially resolved molecular information for carbon and oxygen. Application of STXM/NEXAFS to particles collected during a mesocosm study using a unique wave channel facility to generate aerosols shows that the organic volume fraction of aerosols at the aerodynamic diameter size range of 0.18-0.32 μm are a direct function of the biological activity in the sea water. Aerosol organic volume fraction increased from 0.32 for particles generated from seawater containing low biolife to 0.49 and 0.40 for particles produced during phytoplankton blooms. However, the organic volume fraction of aerosols at the aerodynamic diameter size range of 0.56-1 μm did not change with biological activity. Measurements also show that different types of organics can concentrate into aerosols depending on the enzyme activity expressed at the time. Enhanced spectral signatures for aliphatic hydrocarbons were observed during the first phytoplankton bloom compared to a second phytoplankton bloom occurring directly thereafter. The decreased signature of aliphatic organics in the second phytoplankton bloom was correlated with increased lipase activity from heterobacteria. Organic aggregates having similar morphology also differ in composition from their carbon spectra from the two blooms. For July 17, organic aggregates were much richer in hydrocarbons, which showed a remarkably intense C-H absorbance and a broad C-C absorbance. Organic aggregates observed for July 26-27, did not have the C-H and C-C signatures, but contained more polar

  17. Selection of quasi-monodisperse super-micron aerosol particles

    Science.gov (United States)

    Rösch, Michael; Pfeifer, Sascha; Wiedensohler, Alfred; Stratmann, Frank

    2014-05-01

    : Knutson, E. O. and Whitby, K. T.: Aerosol classification by electric mobility: apparatus, theory, and applications. Aerosol Science, 6:443--451, 1975 Raddatz, M., Wiedensohler, A., Wex, H., and Stratmann, F.: Size selection of sub- and super-micron clay mineral kaolinite particles using a custom-built Maxi-DMA. Nucleation and Atmospheric Aerosols, Vol. 1527, AIP Conference Proceedings, pages 457-460. AMER INST PHYSICS, 2013 Boulter, J. E., Cziczo, D. J., Middlebrook, A. M., Thomson, D. S., and Murphy, D. M.: Design and performance of a Pumped Counterflow Virtual Impactor. Aerosol Science and Technology, 40(11): 969-976, 2006 Kulkarni, G., Pekour, M., Afchine, A., Murphy, D. M., and Cziczo, D. J.: Comparison of experimental and numerical studies of the performance characteristics of a pumped counterflow virtual impactor. Aerosol Science and Technology, 45:382-392, 2011

  18. Computational fluid dynamics analysis of aerosol deposition in pebble beds

    Science.gov (United States)

    Mkhosi, Margaret Msongi

    2007-12-01

    The Pebble Bed Modular Reactor is a high temperature gas cooled reactor which uses helium gas as a coolant. The reactor uses spherical graphite pebbles as fuel. The fuel design is inherently resistant to the release of the radioactive material up to high temperatures; therefore, the plant can withstand a broad spectrum of accidents with limited release of radionuclides to the environment. Despite safety features of the concepts, these reactors still contain large inventories of radioactive materials. The transport of most of the radioactive materials in an accident occurs in the form of aerosol particles. In this dissertation, the limits of applicability of existing computational fluid dynamics code FLUENT to the prediction of aerosol transport have been explored. The code was run using the Reynolds Averaged Navier-Stokes turbulence models to determine the effects of different turbulence models on the prediction of aerosol particle deposition. Analyses were performed for up to three unit cells in the orthorhombic configuration. For low flow conditions representing natural circulation driven flow, the laminar flow model was used and the results were compared with existing experimental data for packed beds. The results compares well with experimental data in the low flow regime. For conditions corresponding to normal operating of the reactor, analyses were performed using the standard k-ɛ turbulence model. From the inertial deposition results, a correlation that can be used to estimate the deposition of aerosol particles within pebble beds given inlet flow conditions has been developed. These results were converted into a dimensionless form as a function of a modified Stokes number. Based on results obtained in the laminar regime and for individual pebbles, the correlation developed for the inertial impaction component of deposition is believed to be credible. The form of the correlation developed also allows these results to be applied to pebble beds of different

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

    Energy Technology Data Exchange (ETDEWEB)

    DePaoli, D.W.

    2003-01-22

    -scale system tests. An additional finding from this work is that low-amplitude oscillation may provide an alternative, non-invasive, non-contact means of controlling settling and/or suspension of solids. Further investigation would be necessary to evaluate its utility for radioactive waste treatment applications. This project did not uncover a new technology for radioactive waste treatment. While it may be possible that an efficient electrically driven technology for aerosol treatment could be developed, it appears that other technologies, such as steel and ceramic HEPA filters, can suitably solve this problem. If further studies are to be undertaken, additional fundamental experimentation and modeling is necessary to fully capture the physics; in addition, larger-scale tests are needed to demonstrate the treatment of flowing gas streams through the coupling of acoustic agglomeration with electrocoalescence.

  20. Glyoxal and Methylglyoxal in Atlantic Seawater and marine Aerosol Particles

    Science.gov (United States)

    van Pinxteren, Manuela; Herrmann, Hartmut

    2014-05-01

    )). References: Sinreich et al., Ship-based detection of glyoxal over the remote tropical Pacific Ocean. Atmos. Chem. Phys. 10(23), 11359-11371 (2010). van Pinxteren and Herrmann, Glyoxal and Methylglyoxal in Atlantic Seawater and marine Aerosol Particles: Method development and first application during the Polarstern cruise ANT XXVII/4. Atmos. Chem. Phys. 13, 11791-11802 (2013).

  1. Urban aerosol number size distributions

    Directory of Open Access Journals (Sweden)

    T. Hussein

    2004-01-01

    Full Text Available Aerosol number size distributions have been measured since 5 May 1997 in Helsinki, Finland. The presented aerosol data represents size distributions within the particle diameter size range 8-400nm during the period from May 1997 to March 2003. The daily, monthly and annual patterns of the aerosol particle number concentrations were investigated. The temporal variation of the particle number concentration showed close correlations with traffic activities. The highest total number concentrations were observed during workdays; especially on Fridays, and the lowest concentrations occurred during weekends; especially Sundays. Seasonally, the highest total number concentrations were observed during winter and spring and lower concentrations were observed during June and July. More than 80% of the number size distributions had three modes: nucleation mode (30nm, Aitken mode (20-100nm and accumulation mode (}$'>90nm. Less than 20% of the number size distributions had either two modes or consisted of more than three modes. Two different measurement sites were used; in the first (Siltavuori, 5.5.1997-5.3.2001, the arithmetic means of the particle number concentrations were 7000cm, 6500cm, and 1000cm respectively for nucleation, Aitken, and accumulation modes. In the second site (Kumpula, 6.3.2001-28.2.2003 they were 5500cm, 4000cm, and 1000cm. The total number concentration in nucleation and Aitken modes were usually significantly higher during workdays than during weekends. The temporal variations in the accumulation mode were less pronounced. The lower concentrations at Kumpula were mainly due to building construction and also the slight overall decreasing trend during these years. During the site changing a period of simultaneous measurements over two weeks were performed showing nice correlation at both sites.

  2. Amino acids in Arctic aerosols

    Directory of Open Access Journals (Sweden)

    E. Scalabrin

    2012-07-01

    Full Text Available Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS to analyze 20 amino acids to quantify compounds at fmol m−3 levels. Mean total FAA concentration was 1070 fmol m−3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45–60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m−3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (<0.49 μm and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanics.

  3. An 11-year global gridded aerosol optical thickness reanalysis (v1.0) for atmospheric and climate sciences

    Science.gov (United States)

    Lynch, Peng; Reid, Jeffrey S.; Westphal, Douglas L.; Zhang, Jianglong; Hogan, Timothy F.; Hyer, Edward J.; Curtis, Cynthia A.; Hegg, Dean A.; Shi, Yingxi; Campbell, James R.; Rubin, Juli I.; Sessions, Walter R.; Turk, F. Joseph; Walker, Annette L.

    2016-04-01

    While stand alone satellite and model aerosol products see wide utilization, there is a significant need in numerous atmospheric and climate applications for a fused product on a regular grid. Aerosol data assimilation is an operational reality at numerous centers, and like meteorological reanalyses, aerosol reanalyses will see significant use in the near future. Here we present a standardized 2003-2013 global 1 × 1° and 6-hourly modal aerosol optical thickness (AOT) reanalysis product. This data set can be applied to basic and applied Earth system science studies of significant aerosol events, aerosol impacts on numerical weather prediction, and electro-optical propagation and sensor performance, among other uses. This paper describes the science of how to develop and score an aerosol reanalysis product. This reanalysis utilizes a modified Navy Aerosol Analysis and Prediction System (NAAPS) at its core and assimilates quality controlled retrievals of AOT from the Moderate Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua and the Multi-angle Imaging SpectroRadiometer (MISR) on Terra. The aerosol source functions, including dust and smoke, were regionally tuned to obtain the best match between the model fine- and coarse-mode AOTs and the Aerosol Robotic Network (AERONET) AOTs. Other model processes, including deposition, were tuned to minimize the AOT difference between the model and satellite AOT. Aerosol wet deposition in the tropics is driven with satellite-retrieved precipitation, rather than the model field. The final reanalyzed fine- and coarse-mode AOT at 550 nm is shown to have good agreement with AERONET observations, with global mean root mean square error around 0.1 for both fine- and coarse-mode AOTs. This paper includes a discussion of issues particular to aerosol reanalyses that make them distinct from standard meteorological reanalyses, considerations for extending such a reanalysis outside of the NASA A-Train era, and examples of how

  4. Simulating aerosol microphysics with the ECHAM/MADE GCM – Part I: Model description and comparison with observations

    Directory of Open Access Journals (Sweden)

    A. Lauer

    2005-01-01

    Full Text Available The aerosol dynamics module MADE has been coupled to the general circulation model ECHAM4 to simulate the chemical composition, number concentration, and size distribution of the global submicrometer aerosol. The present publication describes the new model system ECHAM4/MADE and presents model results in comparison with observations. The new model is able to simulate the full life cycle of particulate matter and various gaseous particle precursors including emissions of primary particles and trace gases, advection, convection, diffusion, coagulation, condensation, nucleation of sulfuric acid vapor, aerosol chemistry, cloud processing, and size-dependent dry and wet deposition. Aerosol components considered are sulfate (SO4, ammonium (NH4, nitrate (NO3, black carbon (BC, particulate organic matter (POM, sea salt, mineral dust, and aerosol liquid water. The model is numerically efficient enough to allow long term simulations, which is an essential requirement for application in general circulation models. Since the current study is focusing on the submicrometer aerosol, a coarse mode is not being simulated. The model is run in a passive mode, i.e. no feedbacks between the MADE aerosols and clouds or radiation are considered yet. This allows the investigation of the effect of aerosol dynamics, not interfered by feedbacks of the altered aerosols on clouds, radiation, and on the model dynamics. In order to evaluate the results obtained with this new model system, calculated mass concentrations, particle number concentrations, and size distributions are compared to observations. The intercomparison shows, that ECHAM4/MADE is able to reproduce the major features of the geographical patterns, seasonal cycle, and vertical distributions of the basic aerosol parameters. In particular, the model performs well under polluted continental conditions in the northern hemispheric lower and middle troposphere. However, in comparatively clean remote areas, e

  5. A review of atmospheric aerosol measurements

    Science.gov (United States)

    McMurry, Peter H.

    Recent developments in atmospheric aerosol measurements are reviewed. The topics included complement those covered in the recent review by Chow (JAWMA 45: 320-382, 1995) which focuses on regulatory compliance measurements and filter measurements of particulate composition. This review focuses on measurements of aerosol integral properties (total number concentration, CCN concentration, optical coefficients, etc.), aerosol physical chemical properties (density, refractive index, equilibrium water content, etc.), measurements of aerosol size distributions, and measurements of size-resolved aerosol composition. Such measurements play an essential role in studies of secondary aerosol formation by atmospheric chemical transformations and enable one to quantify the contributions of various species to effects including light scattering/absorption, health effects, dry deposition, etc. Aerosol measurement evolved from an art to a science in the 1970s following the development of instrumentation to generate monodisperse calibration aerosols of known size, composition, and concentration. While such calibration tools permit precise assessments of instrument responses to known laboratory-generated aerosols, unquantifiable uncertainties remain even when carefully calibrated instruments are used for atmospheric measurements. This is because instrument responses typically depend on aerosol properties including composition, shape, density, etc., which, for atmospheric aerosols, may vary from particle-to-particle and are often unknown. More effort needs to be made to quantify measurement accuracies that can be achieved for realistic atmospheric sampling scenarios. The measurement of organic species in atmospheric particles requires substantial development. Atmospheric aerosols typically include hundreds of organic compounds, and only a small fraction (˜10%) of these can be identified by state-of-the-art analytical methodologies. Even the measurement of the total particulate organic

  6. 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.

  7. Characterization of Cooking-Related Aerosols

    Science.gov (United States)

    Niedziela, R. F.; Blanc, L. E.

    2010-12-01

    The temperatures at which food is cooked are usually high enough to drive oils and other organic compounds out of materials which are being prepared for consumption. As these compounds move away from the hot cooking surface and into the atmosphere, they can participate in chemical reactions or condense to form particles. Given the high concentration of cooking in urban areas, cooking-related aerosols likely contribute to the overall amount of particulate matter on a local scale. Reported here are results for the mid-infrared optical characterization of aerosols formed during the cooking of several meat and vegetable samples in an inert atmosphere. The samples were heated in a novel aerosol generator that is designed to collect particles formed immediately above the cooking surface and inject them into a laminar aerosol flow cell. Preliminary results for the chemical processing of cooking-related aerosols in synthetic air will also be presented.

  8. Cloud, Aerosol, and Volcanic Ash Retrievals Using ASTR and SLSTR with ORAC

    Science.gov (United States)

    McGarragh, Gregory; Poulsen, Caroline; Povey, Adam; Thomas, Gareth; Christensen, Matt; Sus, Oliver; Schlundt, Cornelia; Stapelberg, Stefan; Stengel, Martin; Grainger, Don

    2015-12-01

    The Optimal Retrieval of Aerosol and Cloud (ORAC) is a generalized optimal estimation system that retrieves cloud, aerosol and volcanic ash parameters using satellite imager measurements in the visible to infrared. Use of the same algorithm for different sensors and parameters leads to consistency that facilitates inter-comparison and interaction studies. ORAC currently supports ATSR, AVHRR, MODIS and SEVIRI. In this proceeding we discuss the ORAC retrieval algorithm applied to ATSR data including the retrieval methodology, the forward model, uncertainty characterization and discrimination/classification techniques. Application of ORAC to SLSTR data is discussed including the additional features that SLSTR provides relative to the ATSR heritage. The ORAC level 2 and level 3 results are discussed and an application of level 3 results to the study of cloud/aerosol interactions is presented.

  9. Combined observational and modeling efforts of aerosol-cloud-precipitation interactions over Southeast Asia

    Science.gov (United States)

    Loftus, Adrian; Tsay, Si-Chee; Nguyen, Xuan Anh

    2016-04-01

    droplet size and number concentration, but also the spectral width of the cloud droplet size distribution, the 3M scheme is well suited to simulate aerosol-cloud-precipitation interactions within a three-dimensional regional cloud model. Moreover, the additional variability predicted on the hydrometeor distributions provides beneficial input for forward models to link the simulated microphysical processes with observations as well as to assess both ground-based and satellite retrieval methods. In this presentation, we provide an overview of the 7 South East Asian Studies / Biomass-burning Aerosols and Stratocumulus Environment: Lifecycles and Interactions Experiment (7-SEAS/BASELInE) operations during the spring of 2013. Preliminary analyses of pre-monsoon Sc system lifecycles observed during the first-ever deployment of a ground-based cloud radar to northern Vietnam will be also be presented. Initial results from GCE model simulations of these Sc using double-moment and the new 3M bulk microphysics schemes under various aerosol loadings will be used to showcase the 3M scheme as well as provide insight into how the impact of aerosols on cloud and precipitation processes in stratocumulus over land may manifest themselves in simulated remote-sensing signals. Applications and future work involving ongoing 7-SEAS campaigns aimed at improving our understanding of aerosol-cloud-precipitation interactions of will also be discussed.

  10. Classification of Aerosol Retrievals from Spaceborne Polarimetry Using a Multi-Parameter Algorithm

    Science.gov (United States)

    Russell, P. B.; Kacenelenbogen, M. S.; Livingston, J. M.; Hasekamp, O.; Burton, S. P.; Schuster, G. L.; Redemann, J.; Ramachandran, S.; Holben, B. N.

    2013-12-01

    In this presentation we demonstrate application of a new aerosol classification algorithm to retrievals from the POLDER-3 polarimeter on the PARASOL spacecraft. Motivation and method: Since the development of global aerosol measurements by satellites and AERONET, classification of observed aerosols into several types (e,g., urban-industrial, biomass burning, mineral dust, maritime, and various subtypes or mixtures of these) has proven useful to: understanding aerosol sources, transformations, effects, and feedback mechanisms; improving accuracy of satellite retrievals; and quantifying assessments of aerosol radiative impacts on climate. With ongoing improvements in satellite measurement capability, the number of aerosol parameters retrieved from spaceborne sensors has been growing, from the initial aerosol optical depth at one or a few wavelengths to a list that now includes complex refractive index, single scattering albedo (SSA), and depolarization of backscatter, each at several wavelengths; wavelength dependences of extinction, scattering, absorption, SSA, and backscatter; and several particle size and shape parameters. Making optimal use of these varied data products requires objective, multi-dimensional analysis methods. We describe such a method, which uses a modified Mahalanobis distance to quantify how far a data point described by N aerosol parameters is from each of several prespecified classes. The method makes explicit use of uncertainties in input parameters, treating a point and its N-dimensional uncertainty as an extended data point or pseudo-cluster E. It then uses a modified Mahalanobis distance, DEC, to assign that observation to the class (cluster) C that has minimum DEC from the point (equivalently, the class to which the point has maximum probability of belonging). The method also uses Wilks' overall lambda to indicate how well the input data lend themselves to separation into classes and Wilks' partial lambda to indicate the relative

  11. Reformulating atmospheric aerosol thermodynamics and hygroscopic growth into haze and clouds

    Directory of Open Access Journals (Sweden)

    S. Metzger

    2007-01-01

    of mixed solutes. Various applications and a model inter-comparison indicate that a the application is not limited to dilute binary solutions, b sensitive aerosol properties such as the pH of binary and mixed inorganic/organic salt solutions up to saturation can be computed accurately, and c aerosol associated water is important for atmospheric chemistry, visibility, weather and climate.

  12. Reformulating atmospheric aerosol thermodynamics and hygroscopic growth into fog, haze and clouds

    Directory of Open Access Journals (Sweden)

    S. Metzger

    2007-06-01

    computing aerosol properties such as single solute molalities, molal based activities, including activity coefficients for volatile compounds, efflorescence and deliquescence relative humidities of single solute and mixed solutions. Various applications and a model inter-comparison indicate that a the application is not limited to dilute binary solutions, b sensitive aerosol properties such as hygroscopic growth and the pH of binary and mixed inorganic/organic salt solutions up to saturation can be computed accurately, and c aerosol water is central in modeling atmospheric chemistry, visibility, weather and climate.

  13. Atmospheric responses to stratospheric aerosol geoengineering

    Science.gov (United States)

    Ferraro, Angus; Highwood, Eleanor; Charlton-Perez, Andrew

    2013-04-01

    Stratospheric aerosol geoengineering, also called solar radiation management (SRM), involves the injection of aerosol into the stratosphere to increase the planetary albedo. It has been conceieved as a policy option in response to human-induced global warming. It is well-established from modelling studies and observations following volcanic eruptions that stratospheric sulphate aerosols cause global cooling. Some aspects of the climate response, especially those involving large-scale dynamical changes, are more uncertain. This work attempts to identify the physical mechanisms operating in the climate response to stratospheric aerosol geoengineering using idealised model experiments. The radiative forcing produced by the aerosol depends on its type (species) and size. Aerosols absorb terrestrial and solar radiation, which drives stratospheric temperature change. The stratospheric temperature change also depends on aerosol type and size. We calculate the stratospheric temperature change due to geoengineering with sulphate, titania, limestone and soot in a fixed-dynamical-heating radiative model. Sulphate produces tropical heating of up to ~6 K. Titania produces much less heating, whereas soot produces much more. Most aerosols increase the meridional temperature gradient in the lower stratosphere which, by thermal wind balance, would be expected to intensify the zonal winds in the polar vortex. An intermediate-complexity general circulation model is used to investigate the dynamical response to geoengineering aerosols. Atmospheric carbon dioxide concentrations are quadrupled. The carbon dioxide forcing is then balanced using stratospheric sulphate aerosol. We assess dynamical changes in the stratosphere, for example, the frequency of stratospheric sudden warmings and the strength of the Brewer-Dobson overturning circulation. We also assess changes in the strength and position of the tropospheric jets. We compare results for sulphate with those for titania.

  14. Composition and Particle Size Retrievals for Homogeneous Binary Aerosols

    Science.gov (United States)

    Niedziela, R. F.; Argon, P.; Bejcek, L.

    2014-12-01

    Tropospheric aerosols have widely varying compositions, shapes, and sizes. The ability to measure these physical characteristics, coupled with knowledge about their optical properties, can provide insight as to how these particles might participate in atmospheric processes, including their interaction with light. Over the past several years, our laboratory has been involved in developing methods to determine basic physical properties of laboratory-generated particles based on the analysis of infrared extinction spectra of multi-component aerosols. Here we report the results of a complete study on the applicability of well-known refractive index mixing rules to homogeneous binary liquid organic aerosols in an effort to yield in situ measurements of particle size and composition. In particular, we present results for terpenoid (carvone/nopinone) and long-chain hydrocarbon (squalane/squalene) mixtures. The included image shows model carvone/nopinone extinction spectra that were computed using the Lorentz-Lorenz mixing rule on complex refractive index data for the pure components.

  15. Yunnan baiyao aerosol in preventing the application of mechanical phlebitis after PICC catheter%云南白药气雾剂在预防PICC置管后机械性静脉炎的应用

    Institute of Scientific and Technical Information of China (English)

    曾凯瑾

    2015-01-01

    Objective to study the yunnan baiyao aerosol (yunnan baiyao group production) to prevent mechanical phlebitis after PICC catheter.Methods 400 patients with PICC catheter after, based on the principles of voluntary patients were divided into experimental group and control group, 200 cases in each group. Nursing after conventional two groups have to accept, the experimental group on the basis of this combined with yunnan baiyao aerosol spray the puncture point (0.5 cm) to avoid the puncture point 3 cm above the upper arm 1/3 place on the skin.Results: The experimental group phlebitis occurred in 4 cases (2%), 13 cases (6.5%) in the control group, the difference was statistically significant (P< 0.05).Conclusion PICC catheter use yunnan baiyao aerosol prevent phlebitis after effect is better.%目的:探讨云南白药气雾剂(云南白药集团生产)预防PICC置管后机械性静脉炎作用。方法将400例PICC置管后患者按患者自愿原则分为实验组和对照组,每组200例。两组均接受置管后常规护理,实验组在此基础上加用云南白药气雾剂喷穿刺点(避开穿刺点0.5cm)以上宽3cm至上臂上1/3段处皮肤。结果实验组发生静脉炎4例(2%),对照组13例(6.5%),差异有统计学意义(P<0.05)。结论 PICC置管后使用云南白药气雾剂预防静脉炎效果较好。

  16. Investigation on the application status of aerosol inhalation by suburban patients with chronic obstructive pulmonary disease%北京远郊区县某二级医院慢性阻塞性肺疾病患者气雾剂使用情况调查

    Institute of Scientific and Technical Information of China (English)

    马瑞兰; 李伟; 孙玉梅

    2013-01-01

    目的:调查北京郊区医院住院的慢性阻塞性肺疾病( COPD )患者气雾剂的使用情况。方法采用方便抽样法选取82例COPD患者,采用自制问卷对入住呼吸科及非呼吸科患者气雾剂的使用情况进行问卷调查。结果共发放调查问卷82份,回收有效问卷82份,有效回收率为100%。入住呼吸科的COPD患者气雾剂使用得分(5.85±1.35)明显高于入住非呼吸科的患者(2.70±1.65)分,两组比较差异有统计学意义(t=9.27,P<0.01)。直线相关分析结果显示,COPD患者气雾剂使用得分与文化程度、是否入住呼吸科、复诊时是否给予检查呈正相关(r值分别为0.350,0.728,0.511;P<0.05);多元回归分析显示,是否入住呼吸科及患者的文化程度进入沙丁胺醇得分的回归方程(R2=0.58),仅是否入住呼吸科进入舒利迭得分的回归方程( R2=0.37)。结论二级医院应进一步加强非呼吸科医护人员气雾剂使用的专业培训,以提高入住非呼吸科的COPD患者气雾剂正确使用率。%Objective To investigate the application status of aerosol inhalation by suburban patients with chronic obstructive pulmonary disease ( COPD) .Methods A total of 82 patients with COPD were chosen by convenience sampling , and self-designed questionnaires were used to investigate their application of aerosol inhalation .Results Eighty-two questionnaires were handed out and 82 were recovered , with the effective rate of 100%.Patients hospitalized in respiratory department had statistically higher score in application of aerosol inhalation than those who were hospitalized in non-respiratory department ( t =9.27, P <0.01 ).Linear correlation analysis showed that the score was in positive correlation with the patients ’ educational background , whether hospitalized in respiratory department , and whether examined upon further interview with doctors ( r=0

  17. New apparatus of single particle trap system for aerosol visualization

    Science.gov (United States)

    Higashi, Hidenori; Fujioka, Tomomi; Endo, Tetsuo; Kitayama, Chiho; Seto, Takafumi; Otani, Yoshio

    2014-08-01

    Control of transport and deposition of charged aerosol particles is important in various manufacturing processes. Aerosol visualization is an effective method to directly observe light scattering signal from laser-irradiated single aerosol particle trapped in a visualization cell. New single particle trap system triggered by light scattering pulse signal was developed in this study. The performance of the device was evaluated experimentally. Experimental setup consisted of an aerosol generator, a differential mobility analyzer (DMA), an optical particle counter (OPC) and the single particle trap system. Polystylene latex standard (PSL) particles (0.5, 1.0 and 2.0 μm) were generated and classified according to the charge by the DMA. Singly charged 0.5 and 1.0 μm particles and doubly charged 2.0 μm particles were used as test particles. The single particle trap system was composed of a light scattering signal detector and a visualization cell. When the particle passed through the detector, trigger signal with a given delay time sent to the solenoid valves upstream and downstream of the visualization cell for trapping the particle in the visualization cell. The motion of particle in the visualization cell was monitored by CCD camera and the gravitational settling velocity and the electrostatic migration velocity were measured from the video image. The aerodynamic diameter obtained from the settling velocity was in good agreement with Stokes diameter calculated from the electrostatic migration velocity for individual particles. It was also found that the aerodynamic diameter obtained from the settling velocity was a one-to-one function of the scattered light intensity of individual particles. The applicability of this system will be discussed.

  18. Aerosol hygroscopic growth parameterization based on a solute specific coefficient

    Science.gov (United States)

    Metzger, S.; Steil, B.; Xu, L.; Penner, J. E.; Lelieveld, J.

    2011-09-01

    Water is a main component of atmospheric aerosols and its amount depends on the particle chemical composition. We introduce a new parameterization for the aerosol hygroscopic growth factor (HGF), based on an empirical relation between water activity (aw) and solute molality (μs) through a single solute specific coefficient νi. Three main advantages are: (1) wide applicability, (2) simplicity and (3) analytical nature. (1) Our approach considers the Kelvin effect and covers ideal solutions at large relative humidity (RH), including CCN activation, as well as concentrated solutions with high ionic strength at low RH such as the relative humidity of deliquescence (RHD). (2) A single νi coefficient suffices to parameterize the HGF for a wide range of particle sizes, from nanometer nucleation mode to micrometer coarse mode particles. (3) In contrast to previous methods, our analytical aw parameterization depends not only on a linear correction factor for the solute molality, instead νi also appears in the exponent in form x · ax. According to our findings, νi can be assumed constant for the entire aw range (0-1). Thus, the νi based method is computationally efficient. In this work we focus on single solute solutions, where νi is pre-determined with the bisection method from our analytical equations using RHD measurements and the saturation molality μssat. The computed aerosol HGF and supersaturation (Köhler-theory) compare well with the results of the thermodynamic reference model E-AIM for the key compounds NaCl and (NH4)2SO4 relevant for CCN modeling and calibration studies. The equations introduced here provide the basis of our revised gas-liquid-solid partitioning model, i.e. version 4 of the EQuilibrium Simplified Aerosol Model (EQSAM4), described in a companion paper.

  19. Physical characterization of incense aerosols.

    Science.gov (United States)

    Mannix, R C; Nguyen, K P; Tan, E W; Ho, E E; Phalen, R F

    1996-12-20

    Experiments were performed to study the physical characteristics of smoke aerosols generated by burning three types of stick incense in a 4 m3 clean room. Sidestream cigarette smoke was also examined under the same conditions to provide a comparison. Among the parameters measured were (a) masses of aerosol, carbon monoxide and nitrogen oxides generated by burning the incense or cigarettes, (b) rates of decay of the particles from the air, and (c) estimates of count median particle size during a 7 h period post-burning. There was variability among the types of incense studied with respect to many of the parameters. Also, as a general trend, the greater the initial particulate mass concentration, the more rapid the rate of decay of the smoke. In relation to the quantity of particulate generated, cigarette smoke was found to produce proportionally larger quantities of carbon monoxide and nitrogen oxides than did incense. Due to the fact that burning incense was found to generate large quantities of particulate (an average of greater than 45 mg/g burned, as opposed to about 10 mg/g burned for the cigarettes), it is likely, in cases in which incense is habitually burned in indoor settings, that such a practice would produce substantial airborne particulate concentrations.

  20. Organic Aerosol Production from Methylglyoxal

    Science.gov (United States)

    de Haan, D. O.; de Witt, H. L.; Tolbert, M. A.; Jimenez, J. L.

    2009-05-01

    Recent modeling suggests that methylglyoxal may form 27 percent of atmospheric SOA (8 Tg C/yr) if it is irreversibly taken up by clouds and aerosol with an uptake coefficient of 0.0029 (Fu et al. 2008 JGR 113 D15303), less than that measured in two lab studies. Once in a cloud, methylglyoxal may be chemically transformed via oxidation, self-reaction, or reaction with other compounds. All of these processes can combine to prevent re-evaporation. We describe the ability of methylglyoxal to form oligomers with itself, with methylamine, and with ammonium salts in evaporating droplets in lab simulations of cloud processing. Products and reaction kinetics are analyzed by high-resolution time-of-flight aerosol mass spectrometry (HR- ToF-AMS), electrospray ionization mass spectrometry (ESI-MS) and proton nuclear magnetic resonance (1H- NMR). Product molecules are non-volatile, and their formation is irreversible and accompanied by browning. These reactions suggest that SOA formation by methylglyoxal may be very significant.

  1. CCN activity of aliphatic amine secondary aerosol

    Science.gov (United States)

    Tang, X.; Price, D.; Praske, E.; Vu, D.; Purvis-Roberts, K.; Silva, P. J.; Cocker, D. R., III; Asa-Awuku, A.

    2014-01-01

    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 systems.

  2. Aerosol Size Distribution in the marine regions

    Science.gov (United States)

    Markuszewski, Piotr; Petelski, Tomasz; Zielinski, Tymon; Pakszys, Paulina; Strzalkowska, Agata; Makuch, Przemyslaw; Kowalczyk, Jakub

    2014-05-01

    We would like to present the data obtained during the regular research cruises of the S/Y Oceania over a period of time between 2009 - 2012. The Baltic Sea is a very interesting polygon for aerosol measurements, however, also difficult due to the fact that mostly cases of a mixture of continental and marine aerosols are observed. It is possible to measure clear marine aerosol, but also advections of dust from southern Europe or even Africa. This variability of data allows to compare different conditions. The data is also compared with our measurements from the Arctic Seas, which have been made during the ARctic EXperiment (AREX). The Arctic Seas are very suitable for marine aerosol investigations since continental advections of aerosols are far less frequent than in other European sea regions. The aerosol size distribution was measured using the TSI Laser Aerosol Spectrometer model 3340 (99 channels, measurement range 0.09 μm to 7 μm), condensation particle counter (range 0.01 μm to 3 μm) and laser particle counter PMS CSASP-100-HV-SP (range 0.5 μm to 47 μm in 45 channels). Studies of marine aerosol production and transport are important for many Earth sciences such as cloud physics, atmospheric optics, environmental pollution studies and interaction between ocean and atmosphere. All equipment was placed on one of the masts of S/Y Oceania. Measurements using the laser aerosol spectrometer and condensation particle counter were made on one level (8 meters above sea level). Measurements with the laser particle counter were performed at five different levels above the sea level (8, 11, 14, 17 and 20 m). Based on aerosol size distribution the parameterizations with a Log-Normal and a Power-Law distributions were made. The aerosol source functions, characteristic for the region were also determined. Additionally, poor precision of the sea spray emission determination was confirmed while using only the aerosol concentration data. The emission of sea spray depends

  3. 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

  4. Modeling the formation of secondary organic aerosol. 1. Application of theoretical principles to measurements obtained in the alpha-pinene/, beta-pinene/, sabinene/, delta3-carene/, and cyclohexane/ozone systems.

    Science.gov (United States)

    Pankow, J F; Seinfeld, J H; Asher, W E; Erdakos, G B

    2001-03-15

    Secondary organic aerosol (SOA) forms in the atmosphere when volatile parent compounds are oxidized to form low-volatility products that condense to yield organic particulate matter (PM). Under conditions of intense photochemical smog, from 40 to 80% of the particulate organic carbon can be secondary in origin. Because describing multicomponent condensation requires a compound-by-compound identification and quantification of the condensable compounds, the complexity of ambient SOA has made it difficult to test the ability of existing gas/particle (G/P) partitioning theory to predict SOA formation in urban air. This paper examines that ability using G/P data from past laboratory chamber experiments carried out with five parent hydrocarbons (HCs) (four monoterpenes at 308 K and cyclohexene at 298 K) in which significant fractions (61-100%) of the total mass of SOA formed from those HCs were identified and quantified by compound. The model calculations were based on a matrix representation of the multicomponent, SOA G/P distribution process. The governing equations were solved by an iterative method. Input data forthe model included (i) deltaHC (microg m(-3)), the amount of reacted parent hydrocarbon; (ii) the alpha values that give the total concentration T (gas + particle phase, ng m(-3)) values for each product i according to Ti = 10(3) alphaideltaHC; (iii) estimates of the pure compound liquid vapor pressure pL(degrees) values (at the reaction temperature) for the products; and (iv) UNIFAC parameters for estimating activity coefficients in the SOA phase for the products as a function of SOA composition. The model predicts the total amount Mo (microg m(-3)) of organic aerosol that will form from the reaction of deltaHC, the total aerosol yield Y(= Mo/deltaHC), and the compound-by-compound yield values Yi. An impediment in applying the model is the lack of literature data on PL(degrees) values for the compounds of interest or even on pL(degrees) values for other

  5. Smoke and Pollution Aerosol Effect on Cloud Cover

    Science.gov (United States)

    Kaufman, Yoram J.; Koren, Ilan

    2006-01-01

    Pollution and smoke aerosols can increase or decrease the cloud cover. This duality in the effects of aerosols forms one of the largest uncertainties in climate research. Using solar measurements from Aerosol Robotic Network sites around the globe, we show an increase in cloud cover with an increase in the aerosol column concentration and an inverse dependence on the aerosol absorption of sunlight. The emerging rule appears to be independent of geographical location or aerosol type, thus increasing our confidence in the understanding of these aerosol effects on the clouds and climate. Preliminary estimates suggest an increase of 5% in cloud cover.

  6. Potential emission flux to aerosol pollutants over Bengal Gangetic plain through combined trajectory clustering and aerosol source fields analysis

    Science.gov (United States)

    Kumar, D. Bharath; Verma, S.

    2016-09-01

    A hybrid source-receptor analysis was carried out to evaluate the potential emission flux to winter monsoon (WinMon) aerosols over Bengal Gangetic plain urban (Kolkata, Kol) and semi-urban atmospheres (Kharagpur, Kgp). This was done through application of fuzzy c-mean clustering to back-trajectory data combined with emission flux and residence time weighted aerosols analysis. WinMon mean aerosol optical depth (AOD) and angstrom exponent (AE) at Kol (AOD: 0.77; AE: 1.17) were respectively slightly higher than and nearly equal to that at Kgp (AOD: 0.71; AE: 1.18). Out of six source region clusters over Indian subcontinent and two over Indian oceanic region, the cluster mean AOD was the highest when associated with the mean path of air mass originating from the Bay of Bengal and the Arabian sea clusters at Kol and that from the Indo-Gangetic plain (IGP) cluster at Kgp. Spatial distribution of weighted AOD fields showed the highest potential source of aerosols over the IGP, primarily over upper IGP (e.g. Punjab, Haryana), lower IGP (e.g. Uttarpradesh) and eastern region (e.g. west Bengal, Bihar, northeast India) clusters. The emission flux contribution potential (EFCP) of fossil fuel (FF) emissions at surface (SL) of Kol/Kgp, elevated layer (EL) of Kol, and of biomass burning (BB) emissions at SL of Kol were primarily from upper, lower, upper/lower IGP clusters respectively. The EFCP of FF/BB emissions at Kgp-EL/SL, and that of BB at EL of Kol/Kgp were mainly from eastern region and Africa (AFR) clusters respectively. Though the AFR cluster was constituted of significantly high emission flux source potential of dust emissions, the EFCP of dust from northwest India (NWI) was comparable to that from AFR at Kol SL/EL.

  7. Modelling Aerosol Dispersion in Urban Street Canyons

    Science.gov (United States)

    Tay, B. K.; Jones, D. P.; Gallagher, M. W.; McFiggans, G. B.; Watkins, A. P.

    2009-04-01

    Flow patterns within an urban street canyon are influenced by various micrometeorological factors. It also represents an environment where pollutants such as aerosols accumulate to high levels due to high volumes of traffic. As adverse health effects are being attributed to exposure to aerosols, an investigation of the dispersion of aerosols within such environments is of growing importance. In particular, one is concerned with the vertical structure of the aerosol concentration, the ventilation characteristics of the street canyon and the influence of aerosol microphysical processes. Due to the inherent heterogeneity of the aerosol concentrations within the street canyon and the lack of spatial resolution of measurement campaigns, these issues are an on-going debate. Therefore, a modelling tool is required to represent aerosol dispersion patterns to provide insights to results of past measurement campaigns. Computational Fluid Dynamics (CFD) models are able to predict detailed airflow patterns within urban geometries. This capability may be further extended to include aerosol dispersion, by an Euler-Euler multiphase approach. To facilitate the investigation, a two-dimensional, multiphase CFD tool coupled with the k-epsilon turbulence model and with the capa