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Atmospheric chemistry is a branch of atmospheric science that studies the chemistry of the Earth's atmosphere and that of other planets. This multidisciplinary approach of research draws on environmental chemistry, physics, meteorology, computer modeling, oceanography, geology and volcanology, climatology and other disciplines to understand both natural and human-induced changes in atmospheric ...
This allows the generation of stable cold plasma even in ambient air. In the simplest application, ambient air can be directly analyzed. Ionization in flow enables high ion transmission since ion loss is significantly reduced compared to the most commonly used spraying methods in mass spectrometry (cf. ESI, APCI). Consequently, this leads to an ...
In the late 1970s an APCI mass spectrometer system (the TAGA, for Trace Atmospheric Gas Analyzer), mounted in a van for mobile operation, was introduced by SCIEX, [19] [20] providing high sensitivity for monitoring polar organics in ambient air in real time. In 1981 a triple quadrupole mass spectrometer version was produced, allowing real-time ...
Typical usages are as a basis for pressure altimeter calibrations, aircraft performance calculations, aircraft and rocket design, ballistic tables, and meteorological diagrams." [1] For example, the U.S. Standard Atmosphere derives the values for air temperature, pressure, and mass density, as a function of altitude above sea level.
= molar mass of Earth's air: 0.0289644 kg/mol The value of subscript b ranges from 0 to 6 in accordance with each of seven successive layers of the atmosphere shown in the table below. The reference value for ρ b for b = 0 is the defined sea level value, ρ 0 = 1.2250 kg/m 3 or 0.0023768908 slug/ft 3 .
Atmospheric pressure, also known as air pressure or barometric pressure (after the barometer), is the pressure within the atmosphere of Earth. The standard atmosphere (symbol: atm) is a unit of pressure defined as 101,325 Pa (1,013.25 hPa ), which is equivalent to 1,013.25 millibars , [ 1 ] 760 mm Hg , 29.9212 inches Hg , or 14.696 psi . [ 2 ]
Reaction is only possible if energetically allowed, i.e. if the proton affinity of R is higher than the proton affinity of H 2 O (691 kJ/mol [3]).As most components of ambient air possess a lower proton affinity than H 2 O (e.g. N 2, O 2, Ar, CO 2, etc.) the H 3 O + ions only react with VOC trace components and the air itself acts as a buffer gas.
The measurement of pH can become difficult at extremely acidic or alkaline conditions, such as below pH 2.5 (ca. 0.003 mol/dm 3 acid) or above pH 10.5 (above ca. 0.0003 mol/dm 3 alkaline). This is due to the breakdown of the Nernst equation in such conditions when using a glass electrode.