Third, although many of the individual steps have been established experimentally (18), surprisingly, the mechanism of production of MSA from OSC gas phase oxidation
by hydroxyl radicals (OH, daytime) and nitrate radicals (nighttime) remains unclear (31).
The reactions are performed
by hydroxyl radicals (· OH) created by the decomposition of hydrogen peroxide, a powerful oxidizing agent that is used in both household and industrial settings.
Methane is normally held in check
by the hydroxyl radical (OH), which scrubs nearly all of it out of the atmosphere within a decade.
Not exact matches
«All three of these molecules are removed
by the same process — reaction with
hydroxyl,» a
radical formed from water in the atmosphere, explains Nobel Prize - winning chemist F. Sherwood Rowland, who participated in the research.
Methane can be destroyed, however,
by reactions involving an atmospheric «cleanser» called the
hydroxyl free
radical (OH).
A final possibility is that there has been increased formation of the
hydroxyl radical in the atmosphere — perhaps caused
by the thinning of the ozone layer, which allows more ultraviolet radiation to reach low levels.
But in recent years chemists have been increasingly concerned that the atmosphere's reservoir of the
hydroxyl radical, and hence the efficiency of its «cleansing service», has been overstretched
by the build - up of pollutants such as methane, carbon monoxide and sulphur dioxide.
Specifically, the scientists measured the yields of
hydroxyl radicals and nitrite ions produced
by the so - called acoustic cavitation of the bubbles.
Lower in the atmosphere, oxygen atoms and
hydroxyl radicals (OH), which form when water molecules are broken apart
by ultraviolet photons, oxidize methane.
These experiments will first quantify the poorly - known production rates of a) nitric oxide (NO) and b)
hydroxyl radicals (OH)
by cosmic radiation.
One theory is that a small amount of silver goes into solution
by forming a compound of AgOH with the free
hydroxyl radicals in the water.
The two most common ways of creating what is a false alkalinity are use of bicarbonates or drinking water from machines that make alkaline water
by chemically splitting water into a retained
hydroxyl radical that is alkaline and an acid proton that is flushed away.
These free
radicals (such as: superoxide,
hydroxyl radical, and peroxynitrite) are controlled
by antioxidant systems and when these systems can't cope with the amount of free
radicals produced these free
radicals scavenge for electrons from proteins, cell membranes, and DNA.
and 1998 snippets Methane now contributes about 20 % to the increased direct radiative forcing
by greenhouse gases compared to preindustrial times [Shine et al., 1995] Oxidation of CH4 in the troposphere produces carbon monoxide (CO), can lead production of ozone (03), and involves atmospheric oxidant, the
hydroxyl radical (OH).