摘要:

AbstractThe rate of CH4disappearance in a shock‐heated CH4:D2:Ar = 9.70:9.86:80.44 mixture was monitored by coincidence absorption of the 2948 cm−1He‐Ne laser line over the shockfront temperature range of 1900–2300K. Comparison with CH4pyrolysis results by means of computer simulations suggested that atom and free radical chains are responsible for the homogeneous D/H exchange reaction on CH4.Additional simulations for the experimental conditions of previous single‐pulse shock tube experiments led to the recognition of a high sensitivity of the exchange rate to trace amounts of hydrocarbon impurity and to the dissociation ra

ISSN:0538-8066    

DOI:10.1002/kin.550080112

出版商:John Wiley&Sons, Inc.    

年代:1976

数据来源: WILEY

摘要:

AbstractSince the activation energy for the reaction RH + O2→ R· + HO2. is very close to its endothermicity, the R‐H bond energy can be calculated from the activation energy for free radical formation by the reaction RH + O2. The relation betweenEiand QR–Hwas found empirically after measuringEiby the method of inhibitors for the oxidation of cyclohexane,nheptane, and toluene:\documentclass{article}\pagestyle{empty}\begin{document}$${\rm Q}_{{\rm R} - {\rm H}} = E_i + 53{\rm kcal/mole}$$\end{document}The values of QR–Hare calculated from these and earlier experimental data for five hydrocarbons, five phenols, and four aroma

ISSN:0538-8066    

DOI:10.1002/kin.550080113

出版商:John Wiley&Sons, Inc.    

年代:1976

数据来源: WILEY

摘要:

AbstractThe kinetics of the gamma‐radiation induced free‐radical chain reaction in solutions of carbon tetrachloride in cyclohexane (RH) has been investigated in the temperature range of 303–383°K. Trichloromethyl radicals were produced by the reaction of radiolytically generated cyclohexyl radicals with carbon tetrachloride. The kinetics of the following reactions were investigated:The following rate expression was obtained:\documentclass{article}\pagestyle{empty}\begin{document}$$\log {\rm}k_3 /(k_4)^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} ({\rm cm}^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} \cdot {\rm sec}^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}}) = 4.78 \pm 0.08 - (8.81 \pm 0.12)/\theta ^1$$\end{document}The error limits are the standard deviation from the least mean square Arrhenius plots. Effects of phase on the kinetics of reactions (3) and (4) are cons

ISSN:0538-8066    

DOI:10.1002/kin.550080114

出版商:John Wiley&Sons, Inc.    

年代:1976

数据来源: WILEY

摘要:

AbstractThe flash photolysis of HN3was studied by coordinated time‐resolved spectroscopic measurements of HN3NH(a1Δ), NH(X3Σ), NH(c1π), NH(A3π), NH2, and N3following flash photolysis of mixtures of HN3with argon or helium. The primary photolysis is complex, but when the wavelength distribution of the flash is limited to values greater than about 200 nm, the major reactive product is NH(1Δ), or states which quickly decay to NH(1Δ). Disappearance of NH(1Δ) occurs predominantly by the process\documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {{\rm NH(}^1 \Delta {\rm)} + {\rm HN}_{\rm 3} \to {\rm NH}_{\rm 2} + {\rm N}_{\rm 3}} & {k_2 = 9.3 \times 10^{- 11} {\rm cm}^{\rm 3} /{\rm mole} \cdot {\rm sec}} \\ \end{array}$$\end{document}The process has little, if any, energy of activation, and no detectable dependence on the pressure of inert gas below 1 atm. The rate of formation of NH2in its ground vibrational state depends on the inert gas pressure in a way that can be accounted for by vibrational relaxation from initial excited vibrational states. The total amount of NH2is roughly comparable with the amount of HN3decomposed by primary photolysis. The observed N3can be attributed to the NH(1Δ) + HN3reaction, although a smaller amount could also be formed by primary photolysis. The value ofk2is revised upward from the value given in a preliminary report on the basis of a more careful consideration of the effects of Beer's law failure in absorption measurements involving narrow spect

ISSN:0538-8066    

DOI:10.1002/kin.550080115

出版商:John Wiley&Sons, Inc.    

年代:1976

数据来源: WILEY

摘要:

AbstractThe hydrogen abstraction from asymmetrically fluorinated and chlorofluorinated ethanes by chlorine atoms has been investigated in the gas phase between 264 and 333°K using the competition method. Arrhenius parameters for the reaction on both sites of the molecules are discussed

ISSN:0538-8066    

DOI:10.1002/kin.550080116

出版商:John Wiley&Sons, Inc.    

年代:1976

数据来源: WILEY

ISSN:0538-8066    

DOI:10.1002/kin.550080117

出版商:John Wiley&Sons, Inc.    

年代:1976

数据来源: WILEY

ISSN:0538-8066    

DOI:10.1002/kin.550080101

出版商:John Wiley&Sons, Inc.    

年代:1976

数据来源: WILEY