scholarly journals Studies on Photochemical Reactions of Air Pollutants. XIII. Formation of Nitrophenols by the Reactions of Three Toluene Oxides with Nitrogen Dioxide in Air.

1994 ◽  
Vol 42 (12) ◽  
pp. 2426-2429 ◽  
Author(s):  
Kazuhiro NOJIMA ◽  
Chiho ISOGAMI
Keyword(s):  
Nitrogen Dioxide ◽  
Air Pollutants ◽  
Photochemical Reactions

scholarly journals Observations of air composition in Brazil between the Equator and 20°s during the dry season.

1985 ◽  
Vol 15 (1-2) ◽  
pp. 77-120 ◽  
Author(s):  
P.J. Crutzen ◽  
M.T. Coffey ◽  
A.C. Delany ◽  
J. Greenberg ◽  
P. Haagenson ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Carbon Monoxide ◽  
Tropical Forests ◽  
Air Pollutants ◽  
Trace Gases ◽  
Dry Season ◽  
Photochemical Reactions ◽  
Ozone Concentrations ◽  
Air Chemistry ◽  
High Concentrations

Field measurement programs in Brazil during the dry season months of August and September in 1979 and 1980 have demonstrated the great importance of the continental tropics in global air chemistry. Especially in the mixed layer, the air composition over land is much different from that over the ocean and the land areas are clearly longe scale sources of many inportant trace gases. During the dry season much biomass, burning takes place especially in the cerrado regions leading to substantial emission of air pollutants, such as CO, NOx, N2O, CH4 and other hydrocarbons. Ozone concentrations are alsoenhanced due to photochemical reactions. Biogenic organic emissions from tropical forests play likewise an important role in the photochemistry of the atmosphere. Carbon monoxide was found to be present in high concentrations in the boundary layer of the tropical forest, but ozone concentrations were much lower than in the cerrado.

scholarly journals Improving local air quality in cities by reducing nitrogen dioxide pollution from road traffic

2019 ◽  
Vol 122 ◽  
pp. 05002
Author(s):  
Spiru Paraschiv
Keyword(s):  
Air Quality ◽  
Nitrogen Dioxide ◽  
Temporal Variation ◽  
Air Pollutants ◽  
Road Traffic ◽  
Traffic Monitoring ◽  
Monitoring Station ◽  
Daily Minimum

Trucks and buses play a major role in our lives, transporting goods and thousands of people to cities every day. But these vehicles, although in a much smaller number than the car generates a significant amount of air pollutants. The daily NO2 concentrations measured by a traffic monitoring station over a period of two years are used to identify the temporal variation of NO2 pollution as a result of measures to ban the circulation of trucks that do not meet the EURO 6 standard on Stresemannstrase Street in Hamburg. The data shows a decrease in NO2 concentration due to the measure taken so that in January 2017 the maximum daily NO2 concentration was 86 µg/m3 compared to 63 µg/m3 in 2019. There was also a difference between the daily minimum concentrations during the same period, being approximately 28 µg/m3 in 2017 and 10 µg/m3 in 2019. The daily NO2 observations show a significant decrease in concentration since May 2018 when the non-EURO 6 trucks were banned. The largest decrease in daily concentrations was recorded in March 2019 compared with levels in March 2018, with a lower concentration for 28 days. A different situation was observed in October 2018, when compared to October 2017, showed an increase in concentration for 23 days.

scholarly journals The Effects of Air Pollution on COVID-19 Infection and Mortality—A Review on Recent Evidence

2020 ◽  
Vol 8 ◽  
Author(s):  
Nurshad Ali ◽  
Farjana Islam
Keyword(s):  
Public Health ◽  
Air Pollution ◽  
Nitrogen Dioxide ◽  
Air Pollutants ◽  
Health Concern ◽  
Public Health Concern ◽  
Short Term ◽  
The World ◽  
Harmful Effects

The outbreak of COVID-19 has created a serious public health concern worldwide. Although, most of the regions around the globe have been affected by COVID-19 infections; some regions are more badly affected in terms of infections and fatality rates than others. The exact reasons for such variations are not clear yet. This review discussed the possible effects of air pollution on COVID-19 infections and mortality based on some recent evidence. The findings of most studies reviewed here demonstrate that both short-term and long-term exposure to air pollution especially PM2.5 and nitrogen dioxide (NO2) may contribute significantly to higher rates of COVID-19 infections and mortalities with a lesser extent also PM10. A significant correlation has been found between air pollution and COVID-19 infections and mortality in some countries in the world. The available data also indicate that exposure to air pollution may influence COVID-19 transmission. Moreover, exposure to air pollution may increase vulnerability and have harmful effects on the prognosis of patients affected by COVID-19 infections. Further research should be conducted considering some potential confounders such as age and pre-existing medical conditions along with exposure to NO2, PM2.5 and other air pollutants to confirm their detrimental effects on mortalities from COVID-19.

Synergistic effect on field-grown soybeans from combinations of sulfur dioxide and nitrogen dioxide

1984 ◽  
Vol 62 (4) ◽  
pp. 840-846 ◽  
Author(s):  
Patricia M. Irving ◽  
Joseph E. Miller
Keyword(s):  
Sulfur Dioxide ◽  
Synergistic Effect ◽  
Nitrogen Dioxide ◽  
Air Pollutants ◽  
Interactive Effects ◽  
Premature Senescence ◽  
Glycine Max L ◽  
Seed Yields ◽  
Dose Levels ◽  
Field Plots

Gaseous air pollutants are frequently present together in the environment downwind from industrial developments and thus have the potential to cause interactive effects on biological receptors. Accordingly, an investigation was conducted to determine how combinations of the gaseous pollutants, sulfur dioxide (SO2) and nitrogen dioxide (NO2) affect a major crop. Open-air field plots of soybeans (Glycine max L.) were exposed to eight different dose levels of SO2 and NO2, alone and in combination, in the presence of ambient ozone (O3) during 1980 and 1981. The soybean plots were fumigated on 10 occasions in both years of the study during the pod-filling period for an average exposure time during fumigation of approximately 3 h. Mean concentrations during fumigation periods ranged from 0.13 to 0.42 ppm SO2 and 0.06 to 0.40 ppm NO2. Premature senescence, as measured by chlorophyll degradation, was observed in the combined pollutant plots in both years of the experiment. Fumigations with NO2 alone had no effect on seed yields in either year. Exposures with SO2 alone had no effect on yields in 1980 and decreased yields by up to 6% in 1981, possibly as a result of greater concentration peaks. Combinations of SO2 and NO2 had a synergistic effect in both years of the study and resulted in yield decreases ranging from 9 to 25%, depending on pollutant dose.

scholarly journals Atmospheric protein chemistry influenced by anthropogenic air pollutants: nitration and oligomerization upon exposure to ozone and nitrogen dioxide

2017 ◽  
Vol 200 ◽  
pp. 413-427 ◽  
Author(s):  
Fobang Liu ◽  
Pascale S. J. Lakey ◽  
Thomas Berkemeier ◽  
Haijie Tong ◽  
Anna Theresa Kunert ◽  
...  
Keyword(s):  
Nitrogen Dioxide ◽  
Air Pollutants ◽  
Molecular Mechanisms ◽  
Solid Phase ◽  
Bulk Solution ◽  
Protein Oligomerization ◽  
Protein Chemistry ◽  
Post Translational Modification ◽  
Simultaneous Exposure ◽  
Semi Solid

The allergenic potential of airborne proteins may be enhanced via post-translational modification induced by air pollutants like ozone (O3) and nitrogen dioxide (NO2). The molecular mechanisms and kinetics of the chemical modifications that enhance the allergenicity of proteins, however, are still not fully understood. Here, protein tyrosine nitration and oligomerization upon simultaneous exposure of O3 and NO2 were studied in coated-wall flow-tube and bulk solution experiments under varying atmospherically relevant conditions (5–200 ppb O3, 5–200 ppb NO2, 45–96% RH), using bovine serum albumin as a model protein. Generally, more tyrosine residues were found to react via the nitration pathway than via the oligomerization pathway. Depending on reaction conditions, oligomer mass fractions and nitration degrees were in the ranges of 2.5–25% and 0.5–7%, respectively. The experimental results were well reproduced by the kinetic multilayer model of aerosol surface and bulk chemistry (KM-SUB). The extent of nitration and oligomerization strongly depends on relative humidity (RH) due to moisture-induced phase transition of proteins, highlighting the importance of cloud processing conditions for accelerated protein chemistry. Dimeric and nitrated species were major products in the liquid phase, while protein oligomerization was observed to a greater extent for the solid and semi-solid phase states of proteins. Our results show that the rate of both processes was sensitive towards ambient ozone concentration, but rather insensitive towards different NO2 levels. An increase of tropospheric ozone concentrations in the Anthropocene may thus promote pro-allergic protein modifications and contribute to the observed increase of allergies over the past decades.

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