Sökning: "Nitrogen dioxide"

Visar resultat 21 - 25 av 154 avhandlingar innehållade orden Nitrogen dioxide.

  1. 21. On Gas Contaminants, and Bipolar Plates in Proton Exchange Membrane Fuel Cells

    Författare :Yasna Acevedo Gomez; Carina Lagergren; Göran Lindbergh; Rakel Wreland Lindström; Qinfeng Li; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PEM fuel cell; contaminants; ammonia; nitrogen dioxide; degradation; recovery; bipolar plates; electroplating; Ni-Mo; Ni-Mo-P; internal contact resistance; PEM bränslecell; föroreningar; ammoniak; kvävedioxid; degradering; återhämtning; bipolära plattor; elektroplätering; Ni-Mo; Ni-Mo-P; interna kontaktmotståndet; Chemical Engineering; Kemiteknik;

    Sammanfattning : The proton exchange membrane (PEM) fuel cell is an electrochemical device that converts chemical energy into electrical energy through two electrocatalytic reactions. The most common catalyst used is platinum on carbon (Pt/C), which has shown the best performance in the fuel cell until now. LÄS MER

  3. 22. Cardiovascular effects of diesel exhaust : mechanistic and interventional studies

    Författare :Magnus Lundbäck; Anders Blomberg; Benoit Nemery; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; air pollution; diesel exhaust; nitrogen dioxide; endothelin-1; cardiovascular effects; exhaust particle trap; Lung diseases; Lungsjukdomar; lungmedicin; Lung Medicine;

    Sammanfattning : Background: Air pollution is associated with negative health effects. Exposure to combustion-derived particulate matter (PM) air pollution has been related to increased incidence of cardiovascular and respiratory morbidity and mortality, specifically in susceptible populations. Ambient particles, with a diameter of less than 2. LÄS MER

  4. 23. Oxidation of terpenes in indoor environments : A study of influencing factors

    Författare :Linda Pommer; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Environmental chemistry; Monoterpene; Ozone O3 ; Nitrogen dioxide NO2 ; Nitrogen oxide NO ; Relative humidity RH ; Modelling; Scrubber; Experimental design; Interaction; Volatile organic compounds VOC ; Sick buildings syndrome SBS ; Principal component analysis PCA ; Indoor air; Ventilation; Tenax TA; Sodium sulphite; Miljökemi; Environmental chemistry; Miljökemi; analytisk kemi; Analytical Chemistry;

    Sammanfattning : In this thesis the oxidation of monoterpenes by O3 and NO2 and factors that influenced the oxidation were studied. In the environment both ozone (O3) and nitrogen dioxide (NO2) are present as oxidising gases, which causes sampling artefacts when using Tenax TA as an adsorbent to sample organic compounds in the air. LÄS MER

  5. 24. Air Pollution Dependency on Climate Variability and Source Region : Past, Current and Future Air Pollution Scenarios over Europe

    Författare :Camilla Andersson; Hans-Christen Hansson; Christer Johansson; Joakim Langner; David Simpson; Peter Builtjes; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Acidification; Air Pollution; Climate Change; Europe; Numerical Model; Emission; Eutrophication; Key region; Nitrogen Dioxide; Particulate Matter; PM; Source region; Surface Ozone; Tropospheric Ozone; Earth sciences; Geovetenskap; Applied Environmental Science; tillämpad miljövetenskap;

    Sammanfattning : The main objectives of this thesis were to investigate the dependency of European air pollution on climate variability and emission source region. Calculations with a chemistry transport model (CTM) were conducted to investigate the influence of climate variability. LÄS MER

  7. 25. Environmental Factors in Relation to Asthma and Respiratory Symptoms among Schoolchildren in Sweden and Korea

    Författare :Jeong-Lim Kim; Gunilla Wieslander; Dan Norbäck; Lena Elfman; Nils Åberg; Uppsala universitet; []
    Nyckelord :Medical sciences; Allergen; allergy; asthma; dampness; diet; environment; formaldehyde; nitrogen dioxide; plasticizer; schoolchildren; ultrafine particles; MEDICIN OCH VÅRD;

    Sammanfattning : This thesis studied environmental factors in relation to asthma and respiratory symptoms among schoolchildren in two countries. In Sweden, 1014 pupils (5-14 year) in 8 schools participated. Wheeze was reported by 7.8%, current asthma by 5. LÄS MER