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101.
102.
Abraham Zaks 《Israel Journal of Mathematics》1971,9(3):285-289
The purpose of this note is to prove that a Dedekind domain R which contains a field k, and which is a subring ofk[x
1,…,x
n
] is a ring of polynomials. This generalizes similar results of A. Evyatar and A. Zaks on principal ideal domains, and of
P. M. Cohn for the casen=1. Our methods and proofs differ from those introduced previously.
This research was partially supported by the National Science Foundation, Grant GP-23861. 相似文献
103.
Canonical forms are found for all real four-dimensional matrices of the pseudo-orthogonal group which differs from the Lorentz group only in that its metric has twoplus signs and twominus signs. 相似文献
104.
The preparation of macrocyclic thiolactones by condensation of diacyl chlorides with siladithianes is described. 相似文献
105.
Raymond J. Abraham Fahimeh Eivazi R. Nayyir-Mazhir Harry Pearson Kevin M. Smith 《Magnetic resonance in chemistry : MRC》1978,11(1):52-54
Reproducible proton chemical shifts in the porphyrin series are obtained when the spectrum is measured in chloroform using the zinc (II) complex of the porphyrin in the presence of an excess of pyrrolidine. This method is specifically demonstrated for the case of 2,4-dicyanodeuteroporphyrin-IX dimethyl ester which, as the free base, shows dramatic effects due to aggregation phenomena. The shifts obtained using the zinc (II) complex plus pyrrolidine method, which allow compilation of substituent chemical shifts in the porphyrin series, are shown to be the same as the less easily accessible infinite dilution shifts of the porphyrin free bases. 相似文献
106.
The intensity fluctuations of a linearly polarized component of the amplified spontaneous emission at 3.51 μm from a single, variable-length xenon-helium source have been measured. The fluctuations are only slightly reduced despite heavy saturation and the results are found to be in qualitative agreement with theoretical models based on the coupling of the fluctuations in the beams travelling in different directions. 相似文献
107.
Abraham Horowitz 《国际化学动力学杂志》1976,8(5):709-723
The gamma radiation induced decomposition of MeSO2Cl in cyclohexane (RH) was studied between 60 and 150°C. Throughout this temperature range the reaction proceeds by a free radical chain mechanism. Its propagation is described by the following reactions: The kinetic analysis of the results of the experiments with added SO2, which were carried out in the temperature range of 80 to 150°C, gives 14.94 ± 0.92 and 11.91 ± 0.82 kcal/mole for D(Me-SO2) and D(c-C6H11-SO2), respectively. These bond dissociation energies are considerably lower than the gas-phase values, and the possible cause of this difference is discussed. Present results also seem to indicate that D(MeSO2-H) does not exceed 95 kcal/mole. Competitive experiments with added tetrachloroethylene result in where θ = 2.303RT in kcal/mole. 相似文献
108.
109.
110.