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51.
A. N. Kost V. G. Zabrodnyaya Yu. N. Portnov V. G. Voronin 《Chemistry of Heterocyclic Compounds》1980,16(4):368-372
2-Amino-3-(-phthalimidoalkyl)indoles have been obtained by the rearrangement of -phthalimido acid -phenylhydrazides under the action of POCl3. The possibility has been studied of eliminating the phthalyl protective group from these compounds and a convenient method has been developed for obtaining 2-amino-3-(-aminoalkyl)indole dihydrochlorides. The behavior of the 2-amino-3-(-phthalimidoalkyl) indoles in alkylation reactions has been investigated.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 484–488, April, 1980. 相似文献
52.
G. Portnov A.-N. Uthe I. Cruz R. P. Fiffe F. Arias 《Mechanics of Composite Materials》2005,41(3):241-254
The possibility of using forced winding coupled with in situ curing to increase the energy storage capacity of hybrid steel-composite cylindrical flywheels is estimated and analyzed. Stress states for given loading conditions in two- and three-layered compound cylinders made from steel and four different types of unidirectional composites are calculated. For each of these combinations, optimum dimensions and the energy storage capacity of the flywheels are found.__________Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 41, No. 3, pp. 351–372, May–June, 2005. 相似文献
53.
The method of designing a new type of turbine used in flows of various kinds is discussed. Static, kinematic, and constitutive equations for transversely isotropic naturally curved and twisted bars are given, and the hypotheses used are discussed. The statement of the problem is linear and corresponds to small displacements. A method for solving the statically indeterminate problem is proposed. The objectives of numerical calculations, which will comprise the content of the second part of the investigation, are formulated.Translated from Mekhanika Kompozitnykh Materialov, Vol. 34, No. 4, pp. 477–490, July—August, 1998. 相似文献
54.
The results of an investigation of the deformation properties of unidirectional composites are presented, and engineering models which take into account the effect of the nonlinearity of the properties in the radial direction on the state of stress of rings under pressure are proposed. The relations obtained are checked theoretically — by means of a refined calculation based on the nonlinear theory of elasticity — and experimentally — by loading rings with internal and external pressure by means of rubber cuffs in specially designed apparatus.Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. Translated from Mekhanika Polimerov, No. 1, pp. 73–84, January–February, 1976. 相似文献
55.
Conclusions 1. The proposed method of accounting for the nonlinearity of properties of a semifinished product by a piecewise-linear approximation of its stress—strain diagram greatly refines the calculation of stresses induced during the process of winding a product.2. A numerical analysis has revealed the ranges of values of the winding parameters where replacing the nonlinear model by simpler linear models for the calculation is appropriate.Institute of Polymer Mechanics, Academy of Sciences of the Latvian SSR, Riga. Translated from Mekhanika Polimerov, No. 2, pp. 231–240, March–April, 1977. 相似文献
56.
Elastic unbalance of a composite flywheel is considered to be caused by different strain character of the rotating rim due to the distributed material density homogeneity or the corrective mass balancing it in the static state. An analysis has been carried out on the effect of elasticity of the rim flywheel on the linear elastic unbalance and its magnitude for an actual composite flywheel has been calculated. A procedure has been developed for the elimination of unbalance using two corrective masses. The problem of angular unbalance of a rim flywheel has also been considered. The finite element method has been used for computation.Translated from Mekhanika Kompozitnykh Materialov, Vol. 30, No. 4, pp. 552–561, July–August, 1994. 相似文献
57.
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59.
Room-temperature photoacoustic (PA) spectra and jet-cooled action spectra of the first to third overtone regions of the ethyl C-H stretches in vapor phase 1-butyne, CH3CH2C[Triple Bond]C-H, were measured. Both the PA and action spectra exhibit a complex multiple peak structure being better resolved and more pronounced in the latter, due to inhomogeneous structure reduction. The observed manifolds were analyzed in terms of a simplified joint local-/normal-mode (LM/NM) model accounting for two types of C-H stretches (methyl and methylene) and for Fermi resonances between stretches and deformations. The retrieved parameters, used for calculation of the eigenstates, come from the best-fit parameters based on the diagonalization of the vibrational Hamiltonian in the LM/NM basis. The parameters were obtained by comparing the eigenvalues and the sum of the squares of the expansion coefficients of the eigenvectors of the C-H stretches of methyl and methylene to the action spectra peak positions and intensities, respectively. This approximate model vibrational Hamiltonian is proposed to explain most observed spectral features, corresponding to C-H stretch bands and to combinations of C-H stretches and deformations, indicating the importance of the Fermi resonance. The model was also applied to calculate the dynamics of the C-H stretching modes resulting from coupling with the deformations, implying rapid initial state decay on subpicosecond time scale. Decays of several picoseconds were found for complete transfer of probability from the initially prepared state of methylene and methyl to the counterpart LM states. 相似文献
60.
G. A. Golubeva Yu. N. Portnov A. N. Kost L. I. Borisova A. K. Trukhmanov 《Chemistry of Heterocyclic Compounds》1978,14(10):1119-1122
Bromination, nitration, and sulfonation reactions in the acylphenylpyrazolidine series were investigated. 1-(p-Bromophenyl)-2-acylpyrazolidines are formed in good yields in the bromination of these compounds over a wide range of temperatures in various solvents. Removal of the acyl group takes place simultaneously with sulfonation in the para position of the phenyl ring in the sulfonation of phenylacylpyrazolidines with concentrated sulfuric acid at room temperature; the p-sulfophenylpyrazolidines formed in this case exist in the form of betain structures. The nitration of acylphenylpyrazolidines with concentrated nitric acid (sp. gr. 1.52) leads to 1-(2,4-dinitrophenyl)-2-acylpyrazolidines. However, the nitration of these compounds with dilute nitric acid (sp. gr. 1.35) is accompanied by pronounced resinification; both 2,4-dinitrophenyl and p-nitrophenyl-2-acylpyrazolidines, as well as dimers of the latter, were detected among the reaction products.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1377–1380, October, 1978. 相似文献