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91.
Klaus Anderle Richard Birenheide Martin J. A. Werner Joachim H. Wendorff 《Liquid crystals》1991,9(5):691-699
Polarized light leads to an effective reorientation of the optic axis in the glassy state of liquid-crystalline side chain polymers containing azobenzene mesogenic groups, via a trans-cis and cis-trans isomerization. Using a combination of U V and IR dichroitic studies it is shown for copolymers consisting of chromophores (azobenzene) and non-chromophores (phenylbenzoate) that only the chromophores are reoriented by light as far as the glassy state is concerned. Individual chromophores are thus addressed by photoselection. Photoselection in the fluid nematic state, on the other hand, leads also to a reorientation of the non-chromophores. 相似文献
92.
93.
Steven G. Buyske 《Geometriae Dedicata》1992,44(1):7-16
In 1980 Chern and Terng defined a Bäcklund transformation for affine minimal surfaces. In this paper we show that this Bäcklund transformation can be simply represented by an involution and translation of the affine conormal. 相似文献
94.
95.
G. O. Balabanyan 《Theoretical and Mathematical Physics》1991,89(1):1106-1119
Moscow Institute of Electronic Engineering. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 89, No. 1, pp. 132–150, October, 1991. 相似文献
96.
A new microscopic model of anomalous muonium for the elemental semiconductors is proposed. The relevant configuration consisting
of both a diamagrentic molecule Si−Mu and an unpaired orbital e− is contained into a semivacancy of the real lattice. By using the unrestricted Hartree-Fock computational method the principal
properties of the system are established. A dynamical version of the model together with a question on the formation of such
system are discussed. 相似文献
97.
A random-medium model which is a correlated distribution of points (particles) randomly positioned in the 3-dimensional space
is considered. The construction of the medium starts from a noncorrelated (Poisson) distribution of parent particles, each
of them initiates a finite Markov chain of its descendants. The complete collection of correlation functions of all orders
within the scope of the model have been obtained. The use of the 3-dimensional stable law (Lévy law) as a transition probability
allows us to present the correlation function in an explicit form.
Proceedings of the XVII Seminar on Stability Problems for Stochastic Models, Kazan, Russian, 1995, Part II. 相似文献
98.
99.
V. G. Lomadze 《Acta Appl Math》1994,34(3):305-312
Kalman's theory is extended to a complete, smooth, and irreducible algebraic curve of arbitrary genus. 相似文献
100.
A method is proposed for evaluating the resistance of a flywheel rim to radial stresses in free rotation. The method is based on loading a rim segment in pure bending and calculating the limiting moment and the corresponding limiting angular velocity. Applicability of the method is substantiated theoretically by investigating the similarity of the radial stress diagrams in rotation and pure bending. The method is verified experimentally for the strained state of a rim segment in pure bending.Translated from Mekhanika Kompozitnykh Materialov, Vol. 29, No. 4, pp. 521–526, July–August, 1993. 相似文献