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This paper examines the non-linear dynamic behaviour of a flexible shaft. The shaft is mounted on two journal bearings and the axial load is supported by a defective hydrodynamic thrust bearing at one end. The defect is a levelness defect of the rotor. The thrust bearing behaviour must be considered to be non-linear because of the effects of the defect. The shaft is modelled with typical beam finite elements including effects such as the gyroscopic effects. A modal technique is used to reduce the number of degrees of freedom. Results show that the thrust bearing defects introduce supplementary critical speeds. The linear approach is unable to show the supplementary critical speeds which are obtained only by using non-linear analysis. 相似文献
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Russian Chemical Bulletin - 相似文献
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A. N. Nesmeyanov I. B. Zlotina M. A. Khomutov I. F. Leshcheva N. E. Kolobova K. N. Anisimov 《Russian Chemical Bulletin》1977,26(3):642-643
Conclusions The cis-trans isomers of the vinylic fluorine substitution product were isolated and characterized when Na[5-C5H5Fe(CO)2] is reacted with ethyl perfluoromethacrylate.Deceased.The authors express their gratitude to E. M. Rokhlin and U. Utebaev for supplying the ethyl perfluoromethacrylate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 705–706, March, 1977. 相似文献
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A.B. Antonova N.E. Kolobova P.V. Petrovsky B.V. Lokshin N.S. Obezyuk 《Journal of organometallic chemistry》1977,137(1):55-67
A rearrangement of transition metal acetylenic π-complexes into compounds with vinylidene n-ligands has been established. Compounds CpMn(CCHPh)-(CO)2 and Cp2Mn2(μ-CCHPh)(CO)4 with terminal and bridging phenylvinylidene (benzylidenecarbene) ligands respectively were obtained from the π-complexes CpMn(CO)2(PhCCR) where R H, Ph3Ge or Ph3Sn. Reactions leading to conversion of the terminal CCHPh group into a bridging ligand and vice versa were studied. Under the action of L Ph3P, (EtO)3P or (PhO)3P, substitution of CO groups in vinylidene complexes takes place and compounds CpMn(CCHPh)-(CO)L are formed. IR, 1H and 13C NMR spectra of the novel complexes are discussed. The data obtained indicate an electron-withdrawing property of the CCHPh ligand and stronger bonding of this ligand to the metal as compared with a CO group. 相似文献