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General Introduction
Published in Juan Pablo Silva Vinasco, Greenhouse Gas Emissions from Ecotechnologies for Wastewater Treatment, 2021
The atmosphere is layer of gases surrounding the planet Earth. It contains three primary gases, nitrogen (78.09%), oxygen (20.95%), and argon (0.93%). Furthermore, the atmosphere contains trace gases like carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), nitrous oxide (N2O), nitric oxide (NO), chlorofluorocarbons (CFCs), water vapour (H2O) and ozone (O3).
Atmosphere
Published in Wayne T. Davis, Joshua S. Fu, Thad Godish, Air Quality, 2021
Wayne T. Davis, Joshua S. Fu, Thad Godish
Many of the variable trace gases are produced either biogenically or geogenically. Most important among these are NH3, CH4, H2S, CO, and SO2. Ammonia, CH4, and H2S are produced primarily by biological decomposition. Methane (CH4) is a thermal absorber and serves as a greenhouse gas, and while its global average concentration is only about 1.87 ppmv, its concentration is increasing at about 8 ppbv/year. It is significant that methane has a GWP value of 28. While its concentration in the environment is substantially lower than that of CO2, 1 kg of methane in the atmosphere has the GWP of 28 kg of CO2. Another way of expressing this is to state that 1 kg of methane is equal to 28 kg of carbon dioxide equivalency or 28 kg of CO2e.
Crops and the Atmosphere
Published in Yeqiao Wang, Terrestrial Ecosystems and Biodiversity, 2020
Jürgen Kreuzwieser, Heinz Rennenberg
The atmosphere mainly consists of nitrogen (78% by volume), oxygen (21% by volume) and the noble gas argon (0.93% by volume) together making up >99.9% of the atmosphere’s composition; the remainder is known as trace gases. Trace gases are typically present in the range of parts per trillion by volume (pptv) to parts per million by volume (ppmv); they include the greenhouse gases carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), ethane, water vapor, and ozone (O3); the air pollutants sulfur dioxide (SO2), ammonia (NH3), nitric oxide (NO), nitrogen dioxide (NO2), peroxyacylnitrates (PAN), nitric acid (HNO3), and carbon monoxide (CO); and a number of volatile organic compounds (VOCs) (Table 30.1). Among VOCs are isoprenoids (mainly isoprene and monoterpenes) and many oxygenated species such as alcohols, aldehydes, and organic acids.[2] Because of their reactivity, VOCs strongly affect the oxidation capacity of the troposphere and influence the concentration and distribution of several other trace gases, including CH4 or CO.[3] On a regional scale, VOCs significantly contribute to the formation of tropospheric O3.[4] The main source of VOCs (~90%) is natural emission by vegetation.[2]
Countermeasures against coal spontaneous combustion: a review
Published in International Journal of Coal Preparation and Utilization, 2022
There are relatively long atmospheric lifetimes of trace gases, that is elements and compounds such as water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), etc. which contribute to the greenhouse effect but make up less than 1% of the earth’s atmosphere (Carras et al. 2009). They can be carried over long distances when released from coal fires. Widespread dust and air pollution, also far from the original source could be the result. Transport of pollutant, especially of visible and odorous compounds, causes problem between coal mines and neighboring environments. Concerned residents frequently complain about the production of dust; they are concerned about the health effects of such emissions (Evans and Bennett 1998; Finkelman 2004).
Laboratory study of bioaerosols: Traditional test systems, modern approaches, and environmental control
Published in Aerosol Science and Technology, 2020
Joshua L. Santarpia, Shanna Ratnesar-Shumate, Allen Haddrell
Tropospheric trace gas species, both anthropogenic and biogenic, are known to play a significant role in atmospheric aerosol properties, including biological aerosol. Although some gas-phase species may interact directly with biological particles, it is often the products of gas-phase reactions and specifically reactions driven by sunlight that have the most significant affects. These chemical interactions can change not only the viability of the organisms in the biological particle, but other biological properties that can impact measurement of the particle by other modalities including PCR, protein assays and UV-excited auto fluorescence (e.g., Pan, Santarpia, et al. 2014; Ratnesar-Shumate et al. 2015; Kinahan et al. 2019).
FTIR spectrum of vinyl fluoride near 3.6 μm: rovibrational analysis of the ν4+ν7 band and modelling Coriolis resonances in a seven-level polyad
Published in Molecular Physics, 2018
P. Stoppa, A. De Lorenzi, A. Pietropolli Charmet, S. Giorgianni, N. Tasinato, A. Gambi
It is well known that infrared (IR) spectroscopy is a very powerful method for detecting trace gases, but in order to profit from the sensitivity of this technique, accurate spectroscopic parameters are needed. The molecular constants, obtained from the analysis of high-resolution spectra, are useful not only in detecting and modelling these atmospheric pollutants, but also to improve the theoretical studies on their reactivity and to understand the interaction mechanism for the observed perturbations among the neighbouring rovibrational levels.