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Fred Ustina 《Annali di Matematica Pura ed Applicata》1970,85(1):21-47
Summary Let a2π-periodic function f(x, y) be continuous in some neighbourhood of the point (x, y) except possibly along finitely many lines
l
1
, l
2
, ..., lk terminating at (x, y). The problem of convergence of the Fourier series of f(x, y) at the point (x, y) is examined in some
detail. It is established that under certain restrictions on the variation of f(x, y), and also on the lines l
1
, l
2
, ..., lk, the fourier series converges to a value bounded above by the limit superior, and below by the limit inferior of f(x+u, y+v),
u, v →0, this value depending on the manner in which the series is summed.
The preparation of this paper was financed, in part, by a Canadian Mathematical Congress Summer Research Grant (1968).
Entrata in Redazione il 3 febbraio 1969. 相似文献
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Syntheses of protected versions of the dihydroxyoctadienoic acid fragments corresponding to roridin A and trichoverrin B are described. 相似文献
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Fred B. Wampler 《国际化学动力学杂志》1976,8(6):935-943
The photolysis of SO2 in the presence of cis- and trans-2-pentene has been investigated at 3660 Å and 22°C. Quantum yield measurements of the SO2 photosensitized conversion of one isomer into the other are consistent with a mechanism in which the only participating excited electronic state of SO2 is the SO2(3B1) state. Quantum yield measurements were made for a variation in PSO2/Pisomer reactant ratios of 4.01–283 and 57.5–351 for the cis and trans isomers, respectively. The data are consistent with a mechanism in which a (SO2-olefin)3 collision intermediate is the precursor to the photosensitized isomeric products. The intermediate undergoes unimolecular decay to yield the cis and trans isomers with probabilities of 0.26 ± 0.05 and 0.69 ± 0.04, respectively. Estimates of the quenching rate constants at 22°C for removal of SO2(3B1) molecules by cis- and trans-2-pentene are (0.633 ± 0.125) × 1011 l./mole/sec and (1.00 ± 0.27) × 1011 l./mole/sec, respectively. An experimentally determined photostationary composition, [trans-2-pentene]/[cis-2-pentene] = 2.3 ± 0.1 was in fair agreement with that of 1.7 ± 0.7 as predicted from kinetic data derived in this study. 相似文献
69.
We review the properties of supersymmetric quantum mechanics for a class of models proposed by Witten. Using both Hamiltonian and path integral formulations, we give general conditions for which supersymmetry is broken (unbroken) by quantum fluctuations. The spectrum of states is discussed, and a virial theorem is derived for the energy. We also show that the euclidean path integral for supersymmetric quantum mechanics is equivalent to a classical stochastic process when the supersymmetry is unbroken (E0 = 0). By solving a Fokker-Planck equation for the classical probability distribution, we find Pc(y) is identical to |Ψ0(y)|2 in the quantum theory. 相似文献
70.