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991.
Silver nitrate-acetonitrile and π iodine-benzene complexes in thermotropic liquid crystals have been studied by 1H, 2H, and 13C NMR spectroscopy and by optical microscopy. Evidence for at least two silver complexes in each liquid crystal is presented. 相似文献
992.
A. R. Kuznetsov S. G. Lunter S. I. Nikitina A. G. Plyukhin Yu. K. Fedorov 《Journal of Applied Spectroscopy》1992,56(1):68-72
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 56, No. 1, pp. 90–95, January, 1992. 相似文献
993.
E. A. Ermolaev 《Radiophysics and Quantum Electronics》1992,35(2):141-144
Mogil' Division, Institute of Physics, Belorussian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 35, No. 2, pp. 200–204, February, 1992. 相似文献
994.
M.-K. Chen 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(1):13-18
We examine the influence of relativistic and QED effects on the existence of the 1,3P
o
H- resonances between n
= 2 and 3 hydrogen thresholds, the relativistic and QED corrections and the coupling effects between the high singlet and triplet
states are considered as first-order perturbations. We firstly obtain accurate non-relativistic resonant energies and widths
of fifteen 1P
o
resonances, and fifteen 3P
o
resonances. The fifteen 1P
o
resonances are classified to be
3
(2, 0)
-
n
( 4 ?
n
? 12) and
3
(1, 1)
+
n
( 3 ?
n
? 8). The fifteen 3P
o
resonances are classified to be
3
(2, 0)
+
n
( 3 ?
n
? 12) and
3
(1, 1)
-
n
( 4 ?
n
? 8). We found there exist six Feshbach resonances for
3
(2, 0)
-
n
(1P
o
) series, four Feshbach resonances for
3
(1, 1)
+
n
(1P
o
) series, seven Feshbach resonances for
3
(2, 0)
+
n
(3P
o
) series, and three Feshbach resonances for
3
(1, 1)
-
n
(1P
o
) series.
Received 22 February 2002 Published online 24 September 2002 相似文献
995.
996.
A. S. Kalashnikov 《Journal of Mathematical Sciences》1997,85(6):2287-2301
The paper deals with several problems having the following common feature. The differential equation under consideration contains
a power function of the solution or of its gradient, with the exponent depending on a small parameter. This dependence is
such that a certain property of the solutions corresponding to the positive values of the parameter may disappear as the latter
tends to zero. This phenomenon is shown to be lacking in the case where not only the said exponent, but also the coefficients
of the equation depend on the small parameter in a suitable way. Several theorems are proved on sharp conditions, ensuring
such uniformity of various properties exhibited by the solutions. Bibliography: 44 titles.
Dedicated to Olga Arsenievna Oleinik
This paper has been supported in part by the Russian Foundation for Basic Research (Project 93-013-1744) and by the International
Science Foundation (Grant MIE000).
Translated from Trudy Seminara imeni I. G. Petrovskogo, No. 19, pp. 000-000, 0000. 相似文献
997.
H. R. Ebrahimi-Vishki M. A. Pourabdollah 《Proceedings of the American Mathematical Society》1997,125(7):2171-2174
The purpose of this paper is to introduce an algebra of functions on a semitopological semigroup and to study these functions from the point of view of universal semigroup compactification. We show that the corresponding semigroup compactification of this algebra is universal with respect to the property of being a nilpotent group.
998.
999.
1000.
The numerical solution of a nonlinear and nonlocal system of integro-differential equations that models the contraction of a single heterogeneous muscle fiber is studied. The method proposed is a form of the finite difference method of characteristics. Optimal error bounds are established for the resulting approximation. © 1993 John Wiley & Sons, Inc. 相似文献