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Heisenberg’s Uncertainty Principle E t h/2 h = Plank’s constant E = particle energy t = time This is an important concept in explaining the wave/particle duality of light. Criteria Pollutants
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Heisenberg’s Uncertainty Principle Et h/2 h = Plank’s constant E = particle energy t = time This is an important concept in explaining the wave/particle duality of light.
Criteria Pollutants Those pollutants that have been deemed by EPA to be harmful to human health and/or welfare. SO2, NO2, O3, CO, Pb, PM-10, PM-2.5
Language of Air Pollution Ozone: O3, is a highly reactive gas that exists in the stratosphere and in the troposphere. In the stratosphere it protects us from the short UV wavelengths (very high energy, <280nm) UV-C. In the troposphere it is harmful in high concentrations damaging lungs and DNA. It is formed in the troposphere in reactions triggered by the presence of UV radiation, NOX, and hydrocarbons (mostly from automobile exhausts)
Oxides of Nitrogen: Nitrogen Dioxide (NO2), Nitric Oxide (NO), Nitrous Oxide, N2O, Nitrogen Trioxide (NO3) and Nitrogen Pentoxide (N2O5) all make up a family of nitrogen compounds which damage lung tissue at high concentrations and are major contributors to “smog”. Most are produced from the automobile exhaust and react with oxygen or ozone to produce more photo-reactive pollutants.
Carbon Monoxide: CO, is a colorless, odorless gas produced primarily from automobile exhausts. Can produce headaches, nausea, and in high concentrations death. Forms carboxyhemoglobin in the blood which ties up the oxygen and does not release it to the cells.
Sulfur Dioxide: SO2 is a colorless, acrid gas primarily produced by coal-fired power plants. It is harmful to the lungs and when mixed with water (clouds) can produce H2SO3 (sulfurous acid) which is converted to H2SO4 (sulfuric acid). Acid rain is primarily a sulfur compound reaction. Studies at Mt. Mitchell, NC have shown clouds with pH’s as low as 2.6.
Lead: Pb is a toxic metal that can cause brain damage, especially in children. Since 1992 Pb has been removed from all automotive gasolines. Many older homes can have lead-based paints and lead plumbing. The pipes themselves may be lead or as with copper tubing in older homes, the tubing connections are made with solder which used to contain lead. Pb is derived from the Latin word for lead, plumbum.
Volatile Organic Compounds: VOC’s are a large classification of gaseous organic compounds, which EPA has claimed to cause possible health problems. These compounds are gases at normal temperature and pressure.
Aerosols: These are particulate matter in size ranges from .001 to 100 micrometers (microns, ) that exist primarily in the troposphere and boundary layer. SO4= ions are small aerosols that gather water vapor and other positive ions and lead to acid rain.
PM-10 and PM-2.5: The two latest classifications that EPA has utilized in setting regulations for the amount of particulate matter that can be permitted in the air. The 10 and 2.5 designation refer to the size of the particles in microns(). Particles smaller that 2.5 can easily get into the inner portions of the lungs and cause respiratory problems. = 10 -6 meters
Gaseous Pollutant Monitoring Methodology History Latest methods currently in use are in RED
Carbon Monoxide: Long path IR spectroscopy, Gas Filter Correlation
Notice The Wheel Is Divided In Half. Each Half Has 3 Chambers. One Makes Up A CELL For The Nitrogen (Reference Gas) And The Other Makes Up A Cell For The Gas Of Interest (CO) Fill Port For Cell 2 3 1 Motor Shaft Set Screw 1 3 2 Fill Port For Cell Gas Filter Wheel
Ozone: NBKI, rotamine-B analysis, chemiluminescence, UV absorption, DOAS (Differential optical absorption spectrometry) See my paper!!
Nitrogen Dioxide: Bubblers, Hochheiser method, chemiluminescence, DOAS
Total Oxides of Nitrogen: Chromium trioxide scrubber (oxidized NO to NO2)– colorimetric, chemiluminescence
Sulfur Dioxide: Pararosaniline dye (hourly bubblers read in a photometer for color change), conductivity cell, flame photometric, fluorescence (pulsed, chopped).
Particulate Matter History (Aerosols) High Volume Sampler: Dichotomous Sampler: PM-10 Sampler: PM-2.5 Sampler: Denuders Aethalometer Nephelometer Specialized Samplers: Anderson Impactors