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981.
V. Petržílka 《Czechoslovak Journal of Physics》1968,18(9):1111-1116
A proposal was made to use neutron diffraction to investigate the dynamics of lattice vibrations of piezoelectric resonators. The results obtained explain some experimental facts published in the papers [9, 10, 13]. The obtained spectral distribution of diffracted neutrons is analogous to the spectral distributions of acoustically modulated -rays in the Mössbauer effect.The author is indebted to Assoc. Prof. J. Tichý, RNDr. A. Vancura CSc. and Ing. V. A. Petrílka CSc. for their valuable discussions of the resluts of this paper. 相似文献
982.
983.
984.
985.
986.
1-Dimethylamine-1-carba-closo-dodecaborane(1), 1-(CH3)2NH-1-CB11H11, can be smoothly demethylated with iodine in weakly alkaline solution to produce 1-methylamine-1-carba-closo-dodecarborane(11), 1-CH3NH2-1-CB11H11. The latter compound undergoes formylation with formaldehyde and iodine to give 1-hydroxymethylene-methylamine-1-carba-closo-dodecaborane(11). Further chemical transformations of both compounds are reported. 相似文献
987.
988.
A new simple method has been used to prepare 6-substituted 4-(subst. amino)-5-aryldiazenyl-1-arylpyridazinium salts from N-methyl- or N-aryl-3-amino-1-phenylbut-2-en-1-ones and 4-aminopent-3-en-2-ones and substituted benzenediazonium tetrafluoroborates or hexafluorophosphates. The structure of selected derivatives was studied by means of 15N NMR spectra and X-ray. 相似文献
989.
The Herrlich's problem from [8] whether there are nontrivial classes of topological spaces that are both almost reflective or injective and almost coreflective or projective, is investigated in a more general setting using cone and cocone modifications of the classes used in the problem. We look also at the problem for uniform spaces. Typical results: There is no nontrivial multiprojective and orthogonal class of topological spaces; There is a reflective class of uniform spaces that is almost coreflective in Unif.Work on this paper was initiated while the first author was a C.N.R. visitor of the University of L'Aquila. Partial financial assistence by Charles University Grant 349/1994 is also acknowledged. 相似文献
990.
Miloslav Dušek 《Czechoslovak Journal of Physics》1997,47(2):145-149
Even a very simple proof can show that the collapse of a wave function caused by a quantum measurement on one of two distant (correlated) subsystems cannot be used in any way for an instantaneous transfer of information between observers carrying out measurements on the subsystems. 相似文献