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1.
Sci Total Environ ; 445-446: 155-64, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23333511

RESUMEN

Halogenated gases potentially harmful to the stratospheric ozone layer are monitored worldwide in order to assess compliance with the Montreal Protocol requiring a phase out of these compounds on a global scale. We present the results of long term (2002-2011) continuous observation conducted at the Mt. Cimone GAW Global Station located on the highest peak of the Italian Northern Apennines, at the border of two important regions: the Po Valley (and the Alps) to the North and the Mediterranean Basin to the South. Bi-hourly air samples of CFC-12, CFC-11, CFC-114, CFC-115, H-1211, H-1301, methyl chloroform, carbon tetrachloride, HCFC-22, HCFC-142b, HCFC-124 and methyl bromide are collected and analysed using a gas chromatograph-mass spectrometer, providing multi annual time series. In order to appreciate the effectiveness of the Montreal Protocol from a regional perspective, trends and annual growth rates of halogenated species have been calculated after identification of their baseline values. A comparison with results from other international observation programmes is also presented. Our data show that the peak in the atmospheric mixing ratios of four chlorofluorocarbons, two halons and two chlorocarbons has been reached and all these species now show a negative atmospheric trend. Pollution episodes are still occurring for species like halon-1211, methyl chloroform and carbon tetrachloride, indicating fresh emissions from the site domain which could be ascribed both to fugitive un-reported uses of the compounds and/or emissions from banks. For the hydrofluorocarbons changes in the baseline are affected by emissions from fast developing Countries in East Asia. Fresh emissions from the site domain are clearly declining. Methyl bromide, for which the Mediterranean area is an important source region, shows, in a generally decreasing trend, an emission pattern that is not consistent with the phase-out schedule of this compound, with a renewed increase in the last two years of pollution episodes.


Asunto(s)
Contaminantes Atmosféricos/análisis , Atmósfera/química , Monitoreo del Ambiente , Contaminación Ambiental/análisis , Pérdida de Ozono , Contaminantes Atmosféricos/química , Clorofluorocarburos/análisis , Clorofluorocarburos/química , Contaminación Ambiental/legislación & jurisprudencia , Contaminación Ambiental/prevención & control , Cromatografía de Gases y Espectrometría de Masas , Calentamiento Global , Halogenación , Hidrocarburos Halogenados/análisis , Hidrocarburos Halogenados/química , Italia
2.
Sci Total Environ ; 391(2-3): 232-40, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18054996

RESUMEN

Ground-based in situ measurements of hydrofluorocarbons HFC-125, HFC-134a, and HFC-152a, which are regulated under the Kyoto Protocol, are carried out at four European sites within the SOGE (System of Observation of Halogenated Greenhouse Gases in Europe) program. Concentrations measured at the high mountain stations of Jungfraujoch (Switzerland) and Mte Cimone (Italy) together with back-trajectory statistical analysis are used in order to identify potential source regions on a European scale. Combining concentration data recorded at the two sites allows to reduce one of the problem which is inherent to the back-trajectory approach, i.e. the localisation of "ghost" sources in the wake of real sources. In this way, a more reliable picture of the location of European potential source regions is given.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Hidrocarburos Fluorados/análisis , Altitud , Europa (Continente)
3.
Sci Total Environ ; 391(2-3): 252-61, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18061647

RESUMEN

In this work we present the new ABC-Pyramid Atmospheric Research Observatory (Nepal, 27.95 N, 86.82 E) located in the Himalayas, specifically in the Khumbu valley at 5079 m a.s.l. This measurement station has been set-up with the aim of investigating natural and human-induced environmental changes at different scales (local, regional and global). After an accurate instrumental set-up at ISAC-CNR in Bologna (Italy) in autumn 2005, the ABC-Pyramid Observatory for aerosol (physical, chemical and optical properties) and trace gas measurements (ozone and climate altering halocarbons) was installed in the high Khumbu valley in February 2006. Since March 2006, continuous measurements of aerosol particles (optical and physical properties), ozone (O3) and meteorological parameters as well as weekly samplings of particulate matter (for chemical analyses) and grab air samples for the determination of 27 halocarbons, have been carried out. These measurements provide data on the typical atmospheric composition of the Himalayan area between India and China and make investigations of the principal differences and similarities between the monsoon and pre-monsoon seasons possible. The study is carried out within the framework of the Ev-K2-CNR "SHARE-Asia" (Stations at High Altitude for Research on the Environment in Asia) and UNEP-"ABC" (Atmospheric Brown Clouds) projects. With the name of "Nepal Climate Observatory-Pyramid" the station is now part of the Observatory program of the ABC project.


Asunto(s)
Contaminantes Atmosféricos/análisis , Hidrocarburos Halogenados/análisis , Ozono/análisis , Material Particulado/análisis , Hollín/análisis , Aerosoles , Altitud , Monitoreo del Ambiente , Nepal , Estaciones del Año , Tiempo (Meteorología)
4.
Arch. argent. dermatol ; 52(2): 77-82, mar-abr. 2002. ilus
Artículo en Español | BINACIS | ID: bin-7885

RESUMEN

Se presenta un paciente de 60 años, argentino, con antecedentes de púrpura hipergammaglobulinémica, afectando miembros inferiores y abdomen, desde hace 19 años, con vasculitis leucocitoclástica, factor reumatoideo positivo y crioglobulinemia, asociada con cirrosis por hepatitis crónica por virus C. Es posible que pacientes diagnosticados como púrpura crioglobulinémica estén afectados de hipergammaglobulinas séricas y ambas púrpuras representen una misma enfermedad (AU)


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Púrpura Hiperglobulinémica/diagnóstico , Hepatitis C Crónica/complicaciones , Púrpura Hiperglobulinémica/complicaciones , Púrpura Hiperglobulinémica/clasificación , /complicaciones , Lupus Eritematoso Sistémico/complicaciones , Artritis Reumatoide/complicaciones , Cirrosis Hepática/complicaciones , Mieloma Múltiple/complicaciones , Enfermedad de Mikulicz/complicaciones
5.
Arch. argent. dermatol ; 52(2): 77-82, mar-abr. 2002. ilus
Artículo en Español | LILACS | ID: lil-316235

RESUMEN

Se presenta un paciente de 60 años, argentino, con antecedentes de púrpura hipergammaglobulinémica, afectando miembros inferiores y abdomen, desde hace 19 años, con vasculitis leucocitoclástica, factor reumatoideo positivo y crioglobulinemia, asociada con cirrosis por hepatitis crónica por virus C. Es posible que pacientes diagnosticados como púrpura crioglobulinémica estén afectados de hipergammaglobulinas séricas y ambas púrpuras representen una misma enfermedad


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , Hepatitis C Crónica/complicaciones , Púrpura Hiperglobulinémica/diagnóstico , Artritis Reumatoide , Cirrosis Hepática/complicaciones , Lupus Eritematoso Sistémico/complicaciones , Mieloma Múltiple/complicaciones , Enfermedad de Mikulicz , Púrpura Hiperglobulinémica/clasificación , Púrpura Hiperglobulinémica/complicaciones , Síndrome de Sjögren/complicaciones
7.
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