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11.
Clean endocyclic C-O bond cleavage has been achieved in the reactions of 5-membered phosphate triesters with various nucleophiles.  相似文献   
12.
13.
The production observed in the reactions of α-ferrocenylcarbonium ions with tertiary amines do not originate from ferrocenylcarbene intermediates. Evidence is presented in support of an electron-transfer mechanism leading to α-ferrocenylcarbinyl radicals as reaction intermediates.  相似文献   
14.
It is proposed that the strengths in uniaxial and uniform biaxial compression in the direction of the axes of symmetry be used as parameters. The applicability of a strength criterion in the form of a fourth-degree polynomial to glass-reinforced plastics in biaxial compression in the plane of reinforcement and the transversal plane and to wood in triaxial compression has been experimentally confirmed.S. M. Kirov Leningrad Forest Engineering Academy. Translated from Mekhanika Polimerov, No. 6, pp. 991–996, November–December, 1973.  相似文献   
15.
-Various halides were used to alkylate at both nitrogen atoms of [4.3.3]propell-3-ene-bis-imidi  相似文献   
16.
The title compounds have been isolated and their structures determined by X-ray crystallography. Their relative stability is discussed in terms of theory and experiment. The endo-adduct is the thermodynamically more stable one.  相似文献   
17.
The concept of a strength tensor, analogous to the tensor of elastic constants, has been introduced with a view to using its components for approximate determination of laws governing the variation of strength of anisotropic materials in uniaxial tension or pure shear as a function of the orientation of the stress state. It has been shown that the plasticity condition postulated by Mises can be used as a criterion of strength of many "weakly" anisotropic materials, if one rejects the hypothesis according to which the condition is invariant in respect to hydrostatic pressure. In the case of "strongly" anisotropic materials, wood in particular, the Mises condition is at variance with the results obtained for variously oriented specimens tested in uniaxial tension. A strength condition in the form of a fourth-degree polynomial, based on the assumed existence of a strength tensor analogous to the tensor of elastic constants, has been postulated for these materials. The validity of this criterion has been demonstrated by constructing surfaces of equicritical plane stress states from experimental data obtained for pine wood, plywood, and glass-reinforced plastic laminates.Mekhanika Polimerov, Vol 1, No. 2, pp. 79–92, 1965  相似文献   
18.
The title diketone has been prepared by a synthetic sequence beginning with decane-1,10-dicarboxylic acid.  相似文献   
19.
Reactions of 11-substituted-1, 6-methano [10]annulenes and 1, 6-methano [10]-annulenes substituted in the aromatic ring with the title dienophile are described.  相似文献   
20.
P. Ashkenazi  D. Ginsburg 《Tetrahedron》1979,35(10):1317-1319
Irradiation of a series of [4.4.3]propella-3,8-dienes which differ in the structure of the 5-membered hetero-ring gives in most cases competing intramolecular [2+2] photocycloaddition yielding cage products along with the intermolecular addition products whose configurations were not determined.  相似文献   
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