摘要:

AbstractThe variation of the radiolytic yield of hexachloroethane in the system alkane + carbon tetrachloride can be used to measure the rate constant for the combination of a CCl3radical with an alkyl radical. The treatment of the data for hexane and cyclohexane shows that the rate for a Cl atom transfer must be lower than the high values of Katz et al. and Tuan et al.

ISSN:0538-8066    

DOI:10.1002/kin.550120402

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractThe oxidation of butane 2,3‐, propane 1,2‐, ethane diol and 2‐methoxy ethanol in aqueous alkaline medium by Os(VIII) has been studied. The reaction is base catalyzed and shows first‐order kinetics in Os(VIII), whereas the order is less than 1 in butane 2,3‐diol [BD]. The rate of oxidation is BD>propane 1,2>ethane diol ≈ 2‐methoxy ethanol. The change in ionic strength has no effect on the rate of reaction. Activation parameters ΔE, PZ, and ΔS* have

ISSN:0538-8066    

DOI:10.1002/kin.550120403

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractAtmospheric photodissociation rate coefficients and photodissociation lifetimes for nitromethane, methyl nitrite, and methyl nitrate were calculated as a function of altitude from their measured visible and near ultraviolet photoabsorption cross sections at 298 K. The lifetime of methyl nitrite is nearly independent of altitude and is approximately 2 min. From 0 to 50 km the lifetime of nitromethane varies from 10 to 0.5 hr, while that of methyl nitrate changes from 5.3 to 0.09 days, respectively.

ISSN:0538-8066    

DOI:10.1002/kin.550120404

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractEthylNmethylcarbamate decomposes thermally over the temperature range of 600–650 K by competing first‐order reactions, one forming methylamine, carbon dioxide, and ethylene, the other forming methyl isocyanate and ethanol. The first‐order rate constants are described in S1units by the equationswhereR= 1.986 cal/deg mol. The appareance ofsymdimethylurea among the products raised the possibility of gas‐phase transesterifications. These were ruled out by the study of the reactions ofsym‐dimethylurea at 604 K which showed its behavior to be well explained by the rapid decomposition in the gas phasewhich is reversed in the condensation stage

ISSN:0538-8066    

DOI:10.1002/kin.550120405

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractThe addition of ethene to cyclohexa‐1,3‐diene has been studied between 466 and 591 K at pressures ranging from 27 to 119 torr for ethene and 10 to 74 torr for cyclohexa‐1,3‐diene. The reaction is of the “Diels–Alder” type and leads to the formation of bicyclo[2.2.2]oct‐2‐ene. It is homogeneous and first order with respect to each reagent. The rate constant (in l./mol sec) is given by\documentclass{article}\pagestyle{empty}\begin{document}$$ \log _{10} k_a = - (25,970 \pm 50)/4.576{\rm T + }(6.66 \pm 0.02) $$\end{document}The retron‐Diels–Alder pyrolysis of bicyclo[2.2.2]oct‐2‐ene has also been studied. In the ranges of 548–632 K and 4–21 torr the reaction is first order, and its rate constant (in sec−1) is given by\documentclass{article}\pagestyle{empty}\begin{document}$$ \log _{10} k_p = - (57,300 \pm 100)/4.576{\rm T + }(15.12 \pm 0.04) $$\end{document}The reaction mechanism is discussed. The heat of formation and the entropy of bicycl

ISSN:0538-8066    

DOI:10.1002/kin.550120406

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractThe treatment used for diffusion‐controlled reactions is extended to the case when the final jumplike step of the reagent approach differs essentially from the preceding diffusion. In terms of the model proposed it is possible to take into account, in a simple way, chemical inhomogeneity of the reagents when the in‐cage reaction rate depends on the pair state (for example, on the molecular orientation). In this connection the reaction can be controlled either by the reagent intrusion into the solvation shell of the partner, or by the in‐cage relax

ISSN:0538-8066    

DOI:10.1002/kin.550120407

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

摘要:

AbstractThe lawc=c0exp(K √t) in the alkyl radical abstraction reaction is affected by neither the matrix annealing nor the way of the radical generation. If the reaction runs at varying temperature, a dimensionless time τ which does determine unambiguously the degree of conversion can be introd

ISSN:0538-8066    

DOI:10.1002/kin.550120408

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY

ISSN:0538-8066    

DOI:10.1002/kin.550120401

出版商:John Wiley&Sons, Inc.    

年代:1980

数据来源: WILEY