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81.
82.
83.
In recent years it has become more apparent how useful inequivalent representations of the CCR and CAR in quantum field theory may be in describing and explaining physical phenomena, and several properties and concepts have been stated, referred to, and/or developed in the literature on these ideas. In this paper, some of these are reviewed, and some further properties and concepts are developed as further links in understanding these inequivalent representations in quantum field theory. One of these is a statement as to what actually breaks down in some field theories in the transformation between representations which are unitarily inequivalent. This is developed using the language and ideas of point quantum mechanical invariance, since this should be more familiar to a much larger number of physicists. Also, a statement on state expectation values is developed which can be used as a criterion for the occurrence of inequivalent representations of the CCR and CAR in field theories. 相似文献
84.
Excess isobaric heat capacities of binary mixtures of water with methanol, ethanol, and 1-propanol were obtained from flow microcalorimetric measurements at 25°C over the entire composition range. The results are compared with those of previous investigations. 相似文献
85.
Sidney W. Benson 《国际化学动力学杂志》1992,24(3):217-237
The literature on the pyrolysis of acetylene below 1000 K is reviewed and it is shown that the reaction is a radical chain polymerization initiated by H atoms. The induction period is examined and shown to arise from a rapid autocatalysis produced by the very first product, vinyl acetylene. Data from studies of acetylene polymerization induced by vinyl acetylene and styrene are examined and shown to be in good qualitative agreement with the radical chain process presented. Measured and where needed, estimated rate constants are given to produce numerical estimates of chain length, rates of polymerization, induction period, and rates of initiation. It is further shown that all the products of the polymerization are capable of efficiently initiating chains in the system. An examination of the possible kinetics of vinylidene shows that it does not play any role in acetylene chemistry. 相似文献
86.
87.
H. P. Benson 《Journal of Optimization Theory and Applications》1984,43(3):477-479
We give a corrected version of Theorem 2.1 of Ref. 1.The author is indebted to D. T. Luc, Hungarian Academy of Sciences, Budapest, Hungary, for pointing out his error in the proof of the original version of Theorem 2.1 in Ref. 1. 相似文献
88.
89.
Data on the kinetics of S2F10 pyrolysis, which gives SF4 + SF6, have been reinterpreted to give a value for the equilibrium constant of S2F10 ? SF4 + SF6. This, together with statistical estimates of the entropy and heat capacity of S2F10, can be used to give for this reaction values of ΔH = 19.7 ± 1.0 kcal/mole and ΔS = 47.6 ± 2 gibbs/mole. ΔH(S2F10) = –494 kcal/mole. A compatible mechanism is shown to be S2F10 ? 2SF5 (fast); 2SF5 ? SF6 + SF4 (slow) with step 2 rate-determining. The overall, best first order rate constant is proposed as kmeas = 1017.42–43.0/θ sec?1 = K1k2, where θ = 2.303RT in kcal/mole. Independent measurements of δH and S° for the SF5 radical, permits the evaluation of the equilibrium constant K1 = 108.92–(27.1 ± 6)/θ l./mole-sec and yields k2 = 108.50–15.9/θ l./mole-sec. The observed homogeneous catalysis by NO and CHCl ? CHCl can be explained in terms of a direct abstraction of F from S2F10 : C + S2F10 → CF + S2F9, followed by S2F9 → SF5 + SF4 and SF5 + CF ? SF6 + C (C ? NO or C2H2Cl2). 相似文献
90.
The pyrolysis of ethyl acetate has been studied by the very low-pressure pyrolysis (VLPP) technique. The results obtained agree well with the previously determined high-pressure Arrhenius parameters where log k∞ = 12.6 ? 48.0/θ. The rate constants given by these parameters have also been shown to be consistent with the predictions of the RRK and RRKM theories and demonstrate the applicability of the technique to the study of thermal decompositions. 相似文献