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221.
H. Bungener L. Fries und C. O'Sullivan 《Fresenius' Journal of Analytical Chemistry》1885,24(1):116-119
Ohne Zusammenfassung 相似文献
222.
Based on an analysis of the processes of intramolecular signal transfer (the ordered motion of a quasiparticle, vibron) and structural isomerization, it was pointed out that, in principle, reagents of a new type can be developed with analytical effects fundamentally different from usual ones. The type of analytical response can vary depending on the molecular structure and intramolecular processes induced. General principles of the molecular design of systems of this kind are discussed. 相似文献
223.
Stochastic models of the process of spontaneous ignition of coal particles are distinguished by a pronounced nonlinearity due to the Arrhenius approximation for the constant of the reaction rate and by a complex structure of the stochastic component (noise). We present models describing the dynamics of the distribution of this quantity. The models obtained consist of nonlinear ordinary differential equations, which are solved by numerical methods with the use of computer technologies. 相似文献
224.
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227.
C. Bourrely I. Caprini L. Micu 《The European Physical Journal C - Particles and Fields》2003,27(3):439-446
We derive dispersion relations for decay, using the Lehmann-Symanzik-Zimmermann formalism, which allows the analytic continuation of the amplitudes with respect
to the momenta of the external particles. No off-shell extrapolation of the field operators is assumed. We obtain generalized
Omnès representations, which incorporate the and S-wave phase shifts in the elastic region of the direct and crossed channels, according to the Watson theorem. The contribution
of the inelastic final-state and initial-state interactions is parameterized by the technique of conformal mappings. We compare
our results with previous dispersive treatments and indicate how the formalism can be combined with lattice calculations to
yield physical predictions.
Received: 14 October 2002 / Published online: 14 February 2003 相似文献
228.
José L. Rodrí guez Dirk Scevenels 《Proceedings of the American Mathematical Society》2004,132(3):891-898
Quillen's plus construction is a topological construction that kills the maximal perfect subgroup of the fundamental group of a space without changing the integral homology of the space. In this paper we show that there is a topological construction that, while leaving the integral homology of a space unaltered, kills even the intersection of the transfinite lower central series of its fundamental group. Moreover, we show that this is the maximal subgroup that can be factored out of the fundamental group without changing the integral homology of a space.
229.
Savos'kin M. V. Yaroshenko A. P. Shologon V. I. Galushko L. Ya. 《Russian Journal of Applied Chemistry》2003,76(7):1179-1181
Petroleum sorption on expanded graphite prepared from residual graphite hydrosulfate at 300-900°C was studied as influenced by pretreatment of the sorbent with water. 相似文献
230.
The appearance of a steady current in a helical quantum wire under circularly polarized light is predicted. The effect is associated with the appearance of a travelling electromagnetic wave in the coordinate system related to the wire, the wavelength being determined by the period of the helix. The gyrotropy of a medium consisting of parallel quantum wires is considered. 相似文献