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891.
C. H. Rich G. C. Whittam J. Kent Smith und H. Tusker 《Fresenius' Journal of Analytical Chemistry》1916,55(7):349
Ohne Zusammenfassung 相似文献
893.
894.
Arturo Leon Ligia Gargallo Arturo Horta Deodato Radi 《Journal of Polymer Science.Polymer Physics》1989,27(11):2337-2345
The monoester of itaconic acid with n-decyl alcohol was prepared and polymerized. The polymer was fractionated and characterized by viscometry, size-exclusion chromatography (SEC) and light scattering. Some of the common semiempirical relations for flexible and rigid polymers were used in order to obtain the unperturbed dimensions and the conformational parameters. Thermodynamic and dimensional parameters were determined and calculated. The results are compared with those reported previously for similar compounds. 相似文献
895.
896.
Peter Smith 《Acta Appl Math》1986,6(3):293-308
The usual notion of a saddle functional in the calculus of variations assumes a vex/concave structure over the product space
of two inner product spaces. Here the ideas extended to include some convexity in both spaces whilst still retaining an overall
saddle property. Dual extremum principles are established for these functionals. Examples include periodic solutions of Duffing's
equation, an iterative scheme and a pair of simultaneous partial differential equations which arise in magnetohydrodynamics. 相似文献
897.
B K Smith U K Sieben A Kohlrausch M R Schroeder 《The Journal of the Acoustical Society of America》1986,80(6):1631-1637
Phase effects in masking experiments using multitone maskers are usually associated with strong variations in the masker envelope. In this article, psychoacoustic experiments with such maskers that lead to phase-dependent threshold variations of up to 20 dB, although the phase transformation leaves the envelope unchanged, are described. However, after filtering the maskers with a realistic basilar membrane model, the envelopes are different owing to the models phase-dispersive properties. Comparison of model outputs with the experimental results reveals a strong correlation between the two for a wide range of parameters, provided one makes the additional assumption that the ear has a minimum integration time of a few milliseconds. 相似文献
898.
899.
900.
The Wigner distribution has proven to be a useful tool in many quantum problems requiring a joint distribution of position and momentum. In the present paper we develop a joint distribution for spin components within the spirit of the Wigner distribution. This distribution provides an insight into the quantum theory of measurement. We also discuss how one may write joint distributions for two arbitrary noncommuting operators.It is a pleasure to dedicate this paper to Professor John A. Wheeler—physicist, philosopher, poet—an inspiration to us all.Work supported by the Office of Naval Research. 相似文献