Oxygenated molecules

When investigating time parameters it was shown, that a storage time in Xe of spectral purity was 10 mcs, while a restoring time was 10 ms with subsequent decrease in the case of addition of small amounts of air (less than 1%). As basic processes influencing time parameters, both dissociative recombination and three-particle adhesion of electrons to oxygen molecules have been considered. 

Cheung A S C, Yoshino K, Freeman D E, Friedman R S, Dalgarno A and Parkinson W H 1989 The Schumann-Runge absorption-bands of 0 0 in the wavelength region 175-205 nm and spectroscopic constants of isotopic oxygen molecules J. Mol. Speotroso. 134 362-89... 

A recent study of the vibrational-to-vibrational (V-V) energy transfer between highly-excited oxygen molecules and ozone combines laser-flash photolysis and chemical activation with detection by time-resolved LIF [ ]. Partial laser-flash photolysis at 532 mn of pure ozone in the Chappuis band produces translationally-... 

This greater reactivity of the silanes may be due to several factors, for example, the easier approach of an oxygen molecule (which may attach initially to the silane by use of the vacant silicon d orbitals) and the formation of strong Si—O bonds (stronger than C—O). 

Ozone, O3, is found in trace quantities in the upper atmosphere where it is believed to be formed by the photochemical dissociation of oxygen molecules by the intense ultra-violet light from the sun ... 

High Peroxide Process. An alternative to maximizing selectivity to KA in the cyclohexane oxidation step is a process which seeks to maximize cyclohexyUiydroperoxide, also called P or CHHP. This peroxide is one of the first intermediates produced in the oxidation of cyclohexane. It is produced when a cyclohexyl radical reacts with an oxygen molecule (78) to form the cyclohexyUiydroperoxy radical. This radical can extract a hydrogen atom from a cyclohexane molecule, to produce CHHP and another cyclohexyl radical, which extends the free-radical reaction chain. 

Ozone can be generated by a variety of methods, the most common of which involves the dissociation of molecular oxygen electrically (silent discharge) or photochemicaHy (uv). The short-Hved oxygen atoms (lifetime s) react rapidly with oxygen molecules to form ozone. The widely employed technique... 

Ozone can be destroyed thermally, by electron impact, by reaction with oxygen atoms, and by reaction with electronically and vibrationaHy excited oxygen molecules (90). Rate constants for these reactions are given ia References 11 and 93. Processes involving ions such as 0/, 0/, 0 , 0 , and 0/ are of minor importance. The reaction O3 + 0( P) — 2 O2, is exothermic and can contribute significantly to heat evolution. Efftcientiy cooled ozone generators with typical short residence times (seconds) can operate near ambient temperature where thermal decomposition is small. 

When one of the elements is solid, as in tire case of carbon in the calculation of the partial pressures of tire gaseous species in the reaction between methane and air, CO(g) can be used as a basic element together widr hydrogen and oxygen molecules, and thus the calculation of the final partial pressure of methane must be evaluated using the equilibrium constant for CH4 formation... 

Turbulence is necessary to ensure that the reacting fuel and oxygen molecules in the combustion process are in intimate contact at the proper... 

Stratospheric ozone is in a dynamic equilibrium with a balance between the chemical processes of formation and destruchon. The primary components in this balance are ultraviolet (UV) solar radiation, oxygen molecules (O2), and oxygen atoms (O) and may be represented by the following reactions ... 

The presence of oxygen can modify the course of a fiee-radical chain reaction if a radical intermediate is diverted by reaction with molecular oxygen. The oxygen molecule, with its two unpaired electrons, is extremely reactive toward most free-radical intermediates. The product which is formed is a reactive peroxyl radical, which can propagate a chain reaction leading to oxygen-containing products. 

Sulfur oxides (SO,) are compounds of sulfur and oxygen molecules. Sulfur dioxide (SO2) is the predominant form found in the lower atmosphere. It is a colorless gas that can be detected by taste and smell in the range of 1, (X)0 to 3,000 uglm. At concentrations of 10,000 uglm , it has a pungent, unpleasant odor. Sulfur dioxide dissolves readily in water present in the atmosphere to form sulfurous acid (H SOj). About 30% of the sulfur dioxide in the atmosphere is converted to sulfate aerosol (acid aerosol), which is removed through wet or dry deposition processes. Sulfur trioxide (SO3), another oxide of sulfur, is either emitted directly into the atmosphere or produced from sulfur dioxide and is readily converted to sulfuric acid (H2SO4). 

The decomposition of the nitrates produces oxygen molecules, and we have verified that if a mixture of silver nitrates and closed tubes is submitted to a thermal treatment (400°C) decomposing the salt, it is possible to observe filled CNTs (Ag, Co, Cu [34]). It appears that oxygen liberated during the thermal decomposition of the metal salt erodes the CNT tip and the yet un-decomposed salt then enters by capillarity (see Fig. 8). We have also observed during the electron-irradiation decomposition of enclosed nitrate that the liberated gases erodes the CNT cavity [22] (see the innermost tubes in Fig. 5). 

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