Nitrates, peroxyacetyl

Representation of Atmospheric Chemistry Through Chemical Mechanisms. A complete description of atmospheric chemistry within an air quaUty model would require tracking the kinetics of many hundreds of compounds through thousands of chemical reactions. Fortunately, in modeling the dynamics of reactive compounds such as peroxyacetyl nitrate [2278-22-0] (PAN), C2H2NO, O, and NO2, it is not necessary to foUow every compound. Instead, a compact representation of the atmospheric chemistry is used. Chemical mechanisms represent a compromise between an exhaustive description of the chemistry and computational tractabiUty. The level of chemical detail is balanced against computational time, which increases as the number of species and reactions increases. Instead of the hundreds of species present in the atmosphere, chemical mechanisms include on the order of 50 species and 100 reactions. 

NOj) are exported from the source regions. For example, Honrath and Jaffe (1992) found elevated concentrations of nitrogen oxides at Barrow, Alaska during spring, as compared to summer. This is largely due to decreased removal processes during winter for some nitrogen oxides, such as peroxyacetyl nitrate. 

C09-0114. In the lower atmosphere, NO2 participates in a series of reactions in air that is also contaminated with unbumed hydrocarbons. One product of these reactions is peroxyacetyl nitrate (PAN). The skeletal arrangement of the atoms in PAN appears at the right, (a) Complete the Lewis structure of this compound, (b) Determine the shape around each atom marked with an asterisk, (c) Give the approximate values of the bond angles indicated with arrows. 

The formation of peroxyacetyl nitrate from isoprene (Grosjean et al. 1993a) and of peroxy-propionyl nitrate (Grosjean et al. 1993b) from ctT-3-hexen-l-ol that is derived from higher plants, illustrate important contributions to atmospheric degradation (Seefeld and Kerr 1997). 

Various immobilization and stabilization methods can be applied to soils contaminated with heavy metals, petroleum products, PCB, peroxyacetyl nitrate (PAN), and so on.17 The disadvantages of immobilization and stabilization methods include the following ... 

During SOAPEX-2, measurements of the free-radicals OH, HO2, HO2+XRO2, NO3, IO and OIO were supported by measurements of temperature, wind speed and direction, photolysis rates (j D) and j(N02)), water vapor, O3, HCHO, CO, CH4, NO, NO2, peroxyacetyl nitrate (PAN), a wide range of NMHCs, organic halogens, H2O2, CH3OOH and condensation nuclei (CN). 

Peroxomonosulfuric acid, 18 404—405 Peroxonitrite ion, 18 402 Peroxonitrous acid/salts, 18 402 Peroxophosphoric acids/salts, 18 402-404 Peroxopolyoxometallates, 18 415-416 Peroxosilicates, 18 402 Peroxosulfuric acids/salts, 18 404-405 Peroxotin compounds, 18 402 Peroxyacetic acid, 1 148 14 66, 67 Peroxyacetyl nitrate (PAN), 1 789, 795 Peroxyacids, 18 462 466... 

Complex reactions involving radicals occur, giving rise to secondary pollutants such as ozone, aldehydes, peroxyacetyl nitrate (PAN) and particulate matter. 

Peroxyacetyl nitrate (PAN), H3CCO2ONO2, is a constituent of photochemical smog. It undergoes a first-order decomposition reaction with fi/2 = 32 min. 

Campbell, K. I., G. L. Clarke, L. O. Emik, and R. L. Plata. The atmospheric contaminant peroxyacetyl nitrate. Acute inhalation toxicity in mice. Arch. Environ. Health 15 739-744, 1%7. 

There are obvious inadequacies in the established values. First, it was assumed that the oxidant standard is a surrogate standard for photochemical oxidants, with ozone as the indicator. However, it is clear that very low concentrations of specific irritants, such as peroxyacetyl-nitrate (PAN), are sufficient to cause eye irritation. Second, some of the statistical techniques used to determine the lowest concentration at which effects are observed were inconsistent and undocumented. A hockey stick fimction was sometimes used to find an effect threshold. 

Smith, L. E. Peroxyacetyl nitrate inhalation. Cardiorespiratory effects. Arch. Environ. Health 10 161-164, 1%5. 

Dugger, W. M., and I. P. Ting. The effect of peroxyacetyl nitrate on plants Photoreductive reactions and susceptibility of bean plants to PAN. Phytopathology 58 1102-1107, 1968. 

Leh, F., and J. B. Mudd. Reaction of peroxyacetyl nitrate with cysteine, qrstine. methionine, lipoic acid, papain, and lyso me. Arch. Biochem. Biophys. 161 216-221, 1974. 

Mudd, J. B. Reaction of peroxyacetyl nitrate with utathione. J. Biol. Chem. 241 4077-4080. 1966. 

Ordin, L., M. J. Garber, and J. I. Kindinger. Effect of 2,4-dichlorophenoxyacetic acid on growth and on /1-glucan synthetases of peroxyacetyl nitrate pretreated Avena coleoptile sections. Physiol. Plant. 26 17-23, 1972. 

Peak, M. J., and W. L. Belser. Some effects of the air pollutant, peroxyacetyl nitrate, upon deoxyribonucleic acid and upon nucleic acid bases. Atmos. Environ. 3 385-397, 1%9. 

Starkey. T. E. The Influence of Peroxyacetyl Nitrate on Bean (Phaseobis vulgaris L.) Subjected to Post-Exposure Water Stress. Center for Air Environment Studies. Publ. 400-75. University Park Pennsylvania State University, 1975. 45 pp. 

Thompson, C. R., and G. Kats. Effects of ambient concentrations of peroxyacetyl nitrate on navel orange trees. Environ. Sci. Technol. 9 35-38, 1975. 

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