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Benzo[a]pyrene (BaP or B[a]P) is a polycyclic aromatic hydrocarbon and the result of incomplete combustion of organic matter at temperatures between 300 °C (572 °F) and 600 °C (1,112 °F). The ubiquitous compound can be found in coal tar, tobacco smoke and many foods, especially grilled meats.
This gas is the product of incomplete combustion in a controlled environment. An example mixture is hydrogen gas (H 2 ), nitrogen gas (N 2 ), and carbon monoxide (CO). The hydrogen and carbon monoxide are reducing agents , so they work together to shield surfaces from oxidation.
Black carbon is in the air and circulates the globe. Black carbon travels along wind currents from Asian cities and accumulates over the Tibetan Plateau and Himalayan foothills. Black carbon (BC) is the light-absorbing refractory form of elemental carbon remaining after pyrolysis (e.g., charcoal) or produced by incomplete combustion (e.g., soot).
For example, in piston engines, some of the fuel-air mixture "hides" from the flame in the crevices provided by the piston ring grooves. [1] Further, some regions of the combustion chamber may have a very weak flame, that is, they have either very fuel-lean or very fuel-rich conditions and consequently they have a low combustion temperature.
Soot, particularly diesel exhaust pollution, accounts for over one-quarter of the total hazardous pollution in the air. [ 12 ] [ 22 ] Among these diesel emission components, particulate matter has been a serious concern for human health due to its direct and broad impact on the respiratory organs.
Internal combustion engines such as reciprocating internal combustion engines produce air pollution emissions, due to incomplete combustion of carbonaceous fuel. The main derivatives of the process are carbon dioxide CO 2, water and some soot—also called particulate matter (PM). [55]
Air pollution can cause diseases, allergies, and even death; it can also cause harm to animals and crops and damage the natural environment (for example, climate change, ozone depletion or habitat degradation) or built environment (for example, acid rain). [3] Air pollution can occur naturally or be caused by human activities. [4]
The constant volume adiabatic flame temperature is the temperature that results from a complete combustion process that occurs without any work, heat transfer or changes in kinetic or potential energy. Its temperature is higher than in the constant pressure process because no energy is utilized to change the volume of the system (i.e., generate ...