Aqueous solution data rate constant with hydroxyl radical

Oxidation rate constant k for gas-phase second order rate constants, koH for reaction with OH radical, kNQ3 with N03 radical and kQ3 with 03 or as indicated data at other temperatures see reference photooxidation t,/2 = 14.7-24.4 yr in water, based on measured rate data for the reaction with hydroxyl radical in aqueous solution (Dorfman Adams 1973 selected, Howard et al. 1991) k0H = (4.9 0.4) x 10 13 cm3 molecule1 s 1 with atmospheric lifetimes of 46 d in clean troposphere and 23 d in moderately polluted atmosphere kQ3 < 1.1 x 10-20 cm3 molecule1 s 1 with atmospheric lifetimes of > 4 yr in clean troposphere and > 1.3 yr in moderately polluted atmosphere at room temp, (relative rate method, Atkinson et al. 1987)... 

Surface water ty, = 24-168 h, based on unacclimated freshwater grab sample data (Hammerton 1955 selected, Howard et al. 1991) and aqueous screening test data (Bridie et al. 1979 selected, Howard et al. 1991) photooxidation t,/, = 2602-104000 h, based on measured rate constant for reaction with hydroxyl radicals in aqueous solution (Dorfman Adams 1973 selected, Howard et al. 1991) estimated volatilization half-lives, = 2.4 h in streams, ty = 3.9 h in rivers and ty = 125.9 h in lakes (Lyman et al. 1982 quoted, Howard 1990). 

Oxidation rate constant k, for gas-phase second order rate constants, ko for reaction with OH radical, k os with NO3 radical and ko3 with O3 or as indicated, data at other temperatures see reference photooxidation G, = 0.24-2.4 h for the gas-phase reaction with hydroxyl radical in air, based on the rate of disappearance of hydrocarbon due to reaction with hydroxyl radical (Damall et al. 1976) kojj(exptl) = 1.08 X 10 cm molecule s, k = 6.50 x lO molecule s for the reaction with hydroxyl radical in aqueous solution at 298 K (flash photolysis-resonance fluorescence, Wallington Kurylo 1987) koH = 1.08 X 10" cm molecule s k(soln) = 6.5 x 10cm molecule s for reaction with OH radical in aqueous solution (Wallington et al. 1988b) koH = 10.8 X 10 2 cm molecule s at 296 K (review, Atkinson 1989)... 

Burney S, Niles JC, Dedon PC, Tannenbaum SR (1999) DNA damage in deoxynucleosides and oligonucleotides treated with peroxynitrite. Chem Res Toxicol 12 513-520 Burr JG, Wagner BO, Schulte-Frohlinde D (1976) The rates of electron transfer from ClUra " and CIUraH" top-nitroacetophenone. Int J Radiat Biol 29 433-438 Buxton GV, GreenstockCL, Helman WP, Ross AB (1988) Critical review of rate constants for reactions of hydrated electrons, hydrogen atoms and hydroxyl radicals ( OH/ O-) in aqueous solution. J Phys Chem Ref Data 17 513-886... 

Oxidation rate constant k, for gas-phase second order rate constants, kOH for reaction with OH radical, kNG3 with N03 radical and kG3 with 03 or as indicated, data at other temperatures see reference k0H(calc) = 1.8 x to 12 cm3 molecule-1 s 1 at room temp. (SAR, Atkinson 1987) tropospheric lifetime x(calc) = 8-17 d, based on kOH(calc.) = (1.4 - 2.9) x io 12 cm3 molecule-1 s 1 for dichlorobiphcnyls at room temp. (Atkinson 1987) koH.(aq.) = 7.9 x 109 dm3 mol-1 s-1, PCB in Aroclor 1242 mixture, oxidized by hydroxyl radicals generated with Fenton s reagent in aqueous solutions at 25°C, half-lives range from 4-l 1 d in freshwater systems, 0.1-10 d in cloud water, > 1000 d in oceans for PCBs with as many as 8 chlorines (relative rate method, Sedlak Andren 1991) tropospheric lifetime x(calc) = 3.4-7.2 d, based on the experimentally determined gas-phase reaction kOH(exptl) = (2.0-4.2) x io-12 cm3 molecule-1 s-1, and the calculated kOH(calc) = (1.4 - 3.1) x io-12 cm3 molecule-1 s 1 at room temp. (Kwok et al. 1995)... 

MIC may be released to the environment as a result of its manufacture and use as a chemical intermediate. If MIC is released to soil, it will be expected to rapidly hydrolyze if the soil is moist, based upon the rapid hydrolysis observed in aqueous solution. If released to water, it will be expected to rapidly hydrolyze with half-lives of 20 and 9 min at 15°C and 25°C, respectively, calculated from measured overall hydrolysis rate constants. The products of hydrolysis may include N-carboxymethylamine, methylamine, carbon dioxide, and N,N -dimethylurea. Since it rapidly hydrolyzes, bioconcentration, volatilization, and adsorption to sediment and suspended solids are not expected to be significant processes. No data were located concerning biodegradation, but MIC will probably abiotically hydrolyze significantly faster than it will biodegrade. If released to the atmosphere, it will be expected to exist almost entirely in the vapor phase based upon its vapor pressure. It will be susceptible to photooxidation via vapor phase reaction with photochemically produced hydroxyl radicals. Hydrolysis of MIC in moist air may be significant based upon its rapid hydrolysis in aqueous solution. 

On the introduction of cyclohexane into a Sn(II) aqueous acetonitrile solution, the rate of dioxygen consumption increases and the induction period falls. An increase of cyclohexane concentration decreases the induction period and even causes its complete disappearance. The higher the initial tin concentration, the greater is the cyclohexane concentration necessary to cause the disappearance of the induction period. The rate of hydrogen peroxide production is also increased in the presence of cyclohexane. These data can be understood on the basis of the above chain mechanism of Sn(II) oxidation, where free hydroxyl radicals HO are intermediately formed. The rate constant of the interaction of the hydroxyl radical with cyclohexane... 

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