摘要:

AbstractThe relative rate technique has been used to measure rate constants for the reaction of chlorine atoms with nitro methane, nitro ethane, nitro propane, nitro butane, nitro pentane, ethyl nitrate, isopropyl nitrate,n‐propyl nitrate, 2‐pentyl nitrate, and 2‐heptyl nitrate. Decay rates of these organic species were measured relative to one or more of the following reference compounds;n‐butane, ethane, chloroethane, and methane. Using rate constants of 2.25 × 10−105.7 × 10−11, 8.04 × 10−12, and 1.0 × 10−13cm3molecule−1s−1for the reaction of Cl atoms withn‐butane, ethane, chloroethane, and methane, respectively, the following rate constants were derived, in units of cm3molecule−1s−1: nitro methane,<7 × 10−15; nitro ethane, (2.05 ± 0.14) × 10−13; nitro propane, (1.13 ± 0.05) × 10−11; nitro butane, (5.13 ± 0.68) × 10−11; nitro pentane, (1.40 ± 0.14) × 10−10; ethyl nitrate, (3.70 ± 0.24) × 10−12;n‐propyl nitrate, (2.15 ± 0.13) × 10−11;i‐propyl nitrate, (3.94 ± 0.48) × 10−12; 2‐pentyl nitrate, (1.00 ± 0.06) × 10−10; and 2‐heptyl nitrate, (2.84 ± 0.50) × 10−10. Quoted errors represent 2σ and do not include possible systematic errors due to errors in the reference rate constants. Experiments were performed at 295 ± 2 K and atmospheric pressure (≃740 torr) of synthetic air. The results are discussed with respect to the p

ISSN:0538-8066    

DOI:10.1002/kin.550220702

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe molecular modulation spectroscopic technique was employed to study the kinetics of NO3radicals produced in the 253.7 nm photolysis of flowing gas mixtures of HNO3/CH4/O2at room temperature. By computer fitting of the NO3temporal behavior, a rate coefficient of (2.3 ± 0.7) × 10−12cm3molecule−1s−1was obtained for the reaction between NO3and CH3O2a

ISSN:0538-8066    

DOI:10.1002/kin.550220703

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe initial rate of any generalnth order (nnot necessarily integer) chemical reaction can be accurately and easily computed from the slope of a chord joining two points on the progress curve. Expressions for calculating the intermediate concentration corresponding to this initial rate are provided. Examples of the technique applied to second‐ and third‐order reactions as well as an example of a reaction with fractional order (n= 0.6) are gi

ISSN:0538-8066    

DOI:10.1002/kin.550220704

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe kinetics and mechanism of Cl‐atom initiated reactions of CH3C(O)CHO were studied using the FTIR detection method in the photolysis (λ<300 nm) of Cl2CH3C(O)CHO mixtures in 700 torr of N2O2diluent at 298 ± 2 K. The observed product distribution over the O2pressure range from 0–700 torr, combined with relative rate measurements, provided evidence that: (1) the primary step is Cl + CH3C(O)CHO → HCl + CH3C(O)CO with a rate constant of (4.8 ± 1.1) × 10−11cm3molecule−1s−1; and (2) the predominant fate of the primary radical CH3C(O)CO under atmospheric conditions is unimolecular dissociation to CH3C(O) radicals and CO, rather than O2‐addition to yield the corresponding carbonylperoxy

ISSN:0538-8066    

DOI:10.1002/kin.550220705

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe pyrolysis of 2% CH4and 5% CH4diluted with Ar was studied using both a single–pulse and time–resolved spectroscopic methods over the temperature range 1400–2200 K and pressure range 2.3–3.7 atm. The rate constant expressions for dissociative recombination reactions of methyl radicals, CH3+ CH3→ C2H5+ H and CH3+ CH3→ C2H4+ H2, and for C3H4formation reaction were investigated. The simulation results required considerably lower value than that reported for CH3+ CH3→ C2H4+ H2. Propyne formation was interpreted well by reaction C2H2+ CH3→P‐C3H4+ H with

ISSN:0538-8066    

DOI:10.1002/kin.550220706

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY

摘要:

AbstractRate constants for the gas phase reCedex 2, Franceactions of O(3P) atoms with a series of symmetric aliphatic ethers have been determined using the flash photolysis resonance fluorescence technique over the temperature range 240–400 K. The Arrhenius parameters derived from these data are (in units of cm3molecule−1s−1):\documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{rcl} {\rm dimethyl ether,}k &=& (5.39 \pm 1.94) \times 10^{ - 12} {\rm exp[(} - {\rm 1320} \pm 120)/T]; \\ {\rm diethyl ether,}k &=& (1.42 \pm 0.18) \times 10^{ - 11} {\rm exp[(} - {\rm 1070} \pm 40)/T]; \\ {\rm di -}n{\rm - propyle ether,}k &=& (1.41 \pm 0.21) \times 10^{ - 11} {\rm exp[(} - {\rm 960} \pm 50)/T]; \\ {\rm di -}n{\rm - butyl ether,}k &=& (1.37 \pm 0.29) \times 10^{ - 11} {\rm exp[(} - {\rm 880} \pm 70)/T]; \\ {\rm di -}n{\rm - pentyl ether,}k &=& (1.26 \pm 0.84) \times 10^{ - 11} {\rm exp[(} - {\rm 780} \pm 200)/T]; \\ \end{array} $$\end{document}The error limits are two standard deviations derived from the least‐squares fit. Rate constants for several other ethers were determined only at 298 K. The values obtained were (in units of 10−14cm3molecule−1s−1): tetrahydrofuran (37.5 ± 1.1); 1,4−dioxane 1(6.81 ± 0.46); diethoxymethane (40.4 ± 1.8); ethyl ‐t‐butyl ether (37.0 ± 1.3); and methyl

ISSN:0538-8066    

DOI:10.1002/kin.550220707

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY

摘要:

AbstractHydrogen peroxide formation in the photooxidation of CONOx, etheneNOx, and propeneNOxmixtures has been determined in the TVA 31 cubic meter smog chamber under the following conditions: [NOx] ca. 22–46 ppb; ethene = 0.22–1.1 ppm, [propene]= 0.12–0.97 ppm; [H2O] ca. 8 × 10−3ppm. Ethene, propene, NO, NOx, PAN, HCHO, and CH3CHO were also monitored. Computer modeling was performed using the gas phase ethene and propene mechanism of the Regional Acid Deposition Model. There is good agreement between the model predicted and observed H2O2concentrations. However, to successfully model all the propeneNOxexperimental results, organic nitrate formation from the reaction of peroxy radicals with NO must be included

ISSN:0538-8066    

DOI:10.1002/kin.550220708

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe reaction products of photolysis of acetic anhydride in gas phase at 25°C, where He or CO2was present as buffer gas, were analyzed by gas chromatography. The extent of photodissociation was 52% ± 5% and the extent of intramolecular hydrogen transfer reaction producing acetic acid and ketene was 48% ± 5%. The rate constants of the hydrogen exchange and radical combination reactions between methyl and acetyl radicals were calculated from the amounts of products. The value of the ratio of the rate constants of hydrogen exchange and radical combination reactions between methyl and acetyl radicals,

ISSN:0538-8066    

DOI:10.1002/kin.550220709

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY

摘要:

AbstractThe experimental literature on the pyrolysis of C2H2is reviewed and summarized. These observations divide naturally into three temperature regimes: (i)T<1100 K, where the homogeneous reaction is a molecular polymerization; (ii) 1100

ISSN:0538-8066    

DOI:10.1002/kin.550220710

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY

ISSN:0538-8066    

DOI:10.1002/kin.550220711

出版商:John Wiley&Sons, Inc.    

年代:1990

数据来源: WILEY