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51.
Ohne Zusammenfassung 相似文献
52.
H. P. W. Gottlieb 《International Journal of Theoretical Physics》1990,29(5):461-466
The canonical quantization procedure for homogeneous nonrelativistic strings is extended to inhomogeneous strings having nonconstant density and tension, in fixed-, free-, and closed-boundary configurations. The general oscillator expansion form of the Hamiltonian is maintained. Possibilities of harmonic spectra and corresponding interactions are explored. 相似文献
53.
H.P.W. Gottlieb 《Nuclear Physics B》1974,73(2):257-268
A model containing the massless photon as well as other massive vector mesons is constructed from a gauge-invariant theory of massless vector mesons with scalars transforming under a mixed linear-non-linear group realization, so that one massive scalar also remains finally. A Georgi-Glashow-type Lagrangian in the unitary gauge can be induced by appropriate choice of non-minimal gauge-invariant interactions in the ancestor Lagrangian. It is thus likely that this ancestor Lagrangian, which is non-polynomial, is also renormalizable. 相似文献
54.
The production observed in the reactions of α-ferrocenylcarbonium ions with tertiary amines do not originate from ferrocenylcarbene intermediates. Evidence is presented in support of an electron-transfer mechanism leading to α-ferrocenylcarbinyl radicals as reaction intermediates. 相似文献
55.
Superconformal theories in two-dimensional space-time are considered. Noether's theorem and the Belinfante improvement procedure are extended to superspace where they are used to construct the supercurrent. With its aid, an infinite number of classical conservation laws are derived. These laws are shown to survive quantization in the supersymmetric, non-linear, O(N) sigma model. 相似文献
56.
I.J. Fritz M. Gottlieb T.J. Isaacs B. Morosin 《Journal of Physics and Chemistry of Solids》1981,42(4):269-273
Ultrasonic measurements of the slow shear mode velocity in Tl3AsS4 have been made as a function of hydrostatic pressure up to 2.6 GPa at room temperature. The velocity is a decreasing function of pressure over the entire pressure range. Two pressure-induced phase transitions are observed, one (at 2.1 GPa) characterized by a discontinuous drop in velocity, and the other (at 2.6 GPa) by a continuous softening of the velocity to zero. The results are discussed in terms of the Miller-Axe theory of internal-strain coupling to a soft optic mode. Comparison is made with results on Tl3PSe4, where only one transition is observed. 相似文献
57.
The activity of water in crown ether solutions has been obtained at 298,313 and 333 K over a wide range of concentrations. A minimum in the activity coefficient of water is observed. The minimum becomes more pronounced with decreasing temperature. 相似文献
58.
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60.
Samuel Braverman Tatiana Pechenick Hugo E. Gottlieb Milon Sprecher 《Tetrahedron letters》2004,45(44):8235-8238
The first successful preparation of propargylic and allylic chloroalkoxy disulfides in high yields is reported. Facile 1,4-electrophilic addition of these to 2,3-dimethyl-1,3-butadiene, followed by [2,3]-sigmatropic rearrangements affords mixed allyl allenic and bis-allylic thiosulfinates, respectively. Due to their similarity to allicin, the latter are of potential biological interest. 相似文献