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Atmospheric observations and trends are presented for the high molecular weight perfluorocarbons (PFCs): decafluorobutane (C 4F 10), dodecafluoropentane (C 5F 12), tetradecafluorohexane (C 6F 14), hexadecafluoroheptane (C 7F 16) and octadecafluorooctane (C 8F 18). Their atmospheric histories are based on measurements of 36 Northern Hemisphere and 46 Southern Hemisphere archived air samples collect
We present an analytical method for the in situ measurement of atmospheric nitrogen trifluoride (NF 3), an anthropogenic gas with a 100-year global warming potential of over 16 000. This potent greenhouse gas has a rising atmospheric abundance due to its emission from a growing number of manufacturing processes and an expanding end-use market. Here we present a modified version of the "Medusa" pre
High-frequency in situ measurements at Gosan (Jeju Island, Korea) during November 2007 to December 2008 have been combined with interspecies correlation analysis to estimate national emissions of halogenated compounds (HCs) in East Asia, including the chlorofluorocarbons (CFCs), halons, hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF6),
We report on ground-based atmospheric measurements and emission estimates of the four anthropogenic hydrofluorocarbons (HFCs) HFC-365mfc (CH 3CF2CH2CF3, 1,1,1,3,3- pentafluorobutane), HFC-245fa (CHF2CH2CF3, 1,1,1,3,3-pentafluoropropane), HFC-227ea (CF3CHFCF3, 1,1,1,2,3,3,3-heptafluoropropane), and HFC-236fa (CF3CH 2CF3, 1,1,1,3,3,3-hexafluoropropane). In situ measurements are from the global monit
High-frequency, in situ observations from the Advanced Global Atmospheric Gases Experiment (AGAGE), for the period 2003 to 2012, combined with archive flask measurements dating back to 1977, have been used to capture the rapid growth of HFC-143a (CH3CF3) and HFC- 32 (CH2F2) mole fractions and emissions into the atmosphere. Here we report the first in situ global measurements of these two gases. HF
The legendary cruise of H.M.S. Challenger (1872-1876) around the globe must always occupy an eminent place in the annals of oceanography, as being the first systematic attempt made on a global scale to explore the ocean. This expedition made fundamental discoveries in biology and geology which have not been surpassed by any later scientific cruise. Sediment with high content of metals (later calle
Analysis of naturally occurring isotopic variations is a promising tool for investigating Zn transport and cycling in geological and biological settings. Here, we present the recently installed double-spike (DS) technique at the MAGIC laboratories at Imperial College London. The procedure improves on previous published DS methods in terms of ease of measurement and precisions obtained. The analyti
In an earlier study, we found that rice (Oryza sativa) grown in nutrient solution well-supplied with Zn preferentially took up light 64Zn over 66Zn, probably as a result of kinetic fractionation in membrane transport processes. Here, we measure isotope fractionation by rice in a submerged Zn-deficient soil with and without Zn fertilizer. We grew the same genotype as in the nutrient solution study
We developed an analytical method and constrained procedural boundary conditions that enable accurate and precise Zn isotope ratio measurements in urban aerosols. We also demonstrate the potential of this new isotope system for air pollutant source tracing. The procedural blank is around 5 ng and significantly lower than published methods due to a tailored ion chromatographic separation. Accurate
Zinc isotope ratios were measured in the top sections of dated ombrotrophic peat cores in Finland to investigate their potential as proxies for atmospheric sources and to constrain post depositional processes affecting the geochemical record. The peat deposits were located in Hietajärvi, a background site well away from any point pollution source and representing 'background' conditions, in Outoku
Hydrogen in a hexapole collision cell is used with varying success in multi-collector Inductively Coupled Plasma Mass Spectrometry to reduce the plasma derived interferences 40Ar16O+ and 40Ar16OH+ that are isobaric with 56Fe+ and 57Fe+ respectively. The reactions of ArO+ and ArOH+ with H2 in the hexapole of a multi-collector Inductively Coupled Plasma Mass Spectrometer were studied practically and
PM2.5 low-cost sensors are a promising trend for low-income countries, where the PM2.5 associated burden of disease is high and few measurement instruments are available. Commercially available Sensor Systems (SSys) are relatively affordable and easy to use. They are, however, not designed for or evaluated in contexts characterized by much biomass burning, regular power interruptions and/or low in
Students in a country like Ethiopia face a double air pollution challenge: they are frequently exposed (both outdoors and indoors) to sources of incomplete combustion and therefore to unhealthy concentrations of particulate matter (PM2.5) and carbon monoxide (CO), while they also face increased carbon dioxide (CO2) concentrations in crowded dormitories and classrooms. Research on air pollution in
Exposure to PM2.5 poses one of the biggest health threats, with traffic and biomass burning as dominant sources in urban areas of low-income countries. In Ethiopia, the combination of these two sources suggests a high roadside exposure. Because of a lack of resources for data collection, only few studies were conducted on roadside exposure in Ethiopia. Using low-cost sensors and student science co
A science project as part of a student’s curriculum, which we call student science, might be the answer to two problems for a low-income country like Ethiopia: conventional science can be expensive and many students lack training in practical skills. Earlier studies have been conducted with respect to lay people (citizens or students) conducting (parts of) research (e.g. citizen science), but rare
This thesis studies the relationship between history and nationalism as expressed by the political parties the Sweden Democrats and the Danish People's Party. The study focuses on how the Sweden Democrats and the Danish People's Party convey historical narratives in their party magazines, SD-Kuriren and Dansk Folkeblad, respectively, and in central party documents. The narrative theory being imple
This chapter explores how the two contemporary political parties, the Sweden Democrats and the Danish People’s Party, use the Vikings and the Viking Age as symbols in their national mythmaking. It examines the political dimensions of public history and the way in which these parties draw historical parallels between the Viking Age and the present in order to call for action. The relationship betweThis chapter explores how the two contemporary political parties, the Sweden Democrats and the Danish People’s Party, use the Vikings and the Viking Age as symbols in their national mythmaking. It examines the political dimensions of public history and the way in which these parties draw historical parallels between the Viking Age and the present in order to call for action. The relationship betwe
