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1.
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Anions formed from the lithiation of 1-(1-benzotriazolylalkyl)benzotriazoles (1, 6) and 1-(1-methylthioalkyl)benzotriazoles (10 and 10a) with n-BuLi underwent additions to cyclic and acyclic ketones giving intermediates 3a-f, 7b-f, and 11b-d, respectively, in excellent yields. Thermal rearrangements of intermediates 3a,b,d-f and 7b-d,f in the presence of zinc bromide provided one-carbon chain-extended or ring-expanded alpha-benzotriazolyl ketones 4a,b,d-f and 8b-d,f in moderate yields with excellent regioselectivity. By contrast, intermediates 11b-d on treatment with zinc bromide loose a molecule of benzotriazole followed by intramolecular cyclization of the resulting intermediates 12b-d to provide the 2,3- and 1,2,3-substituted indenes 13b-d in good yields. 相似文献
3.
I. Sh. Abdullin V. S. Zheltukhin I. A. Borodaev E. V. Strebkov A. A. Khubatkhuzin 《Moscow University Physics Bulletin》2014,69(2):185-189
The statistical model of treatment of a polyurethane nanocomposite by low-energy ionic streams in RF plasma at pressure in the range 13.3–133 Pa is developed. The dependence of the permeability of a filled nanocomposite on the filler mass fraction, both before and after RF plasma treatment, is theoretically investigated. 相似文献
4.
We prove in this paper an existence result for frequency modes coupling seismic waves and vibrating tall buildings. The derivation from physical principles of a set of equations modeling this phenomenon was done in previous studies. In this model all vibrations are assumed to be anti-plane and time harmonic so the two dimensional Helmholtz equation can be used. A coupling frequency mode is obtained once we can determine a wavenumber such that the solution of the corresponding Helmholtz equation in the lower half plane with relevant Neumann and Dirichlet conditions at the interface satisfies a specific integral equation at the base of an idealized tall building. Although numerical simulations suggest that such wavenumbers should exist, as far as we know, to date, there is no theoretical proof of their existence. This is what this present study offers to provide. 相似文献
5.
A supersymmetric formulation is proposed for the classical action of interacting charged and neutral fermions with an arbitrary anomalous magnetic moment.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 108, No. 3, pp. 393–405, September, 1996. 相似文献
6.
Kharkov State University; Kharkov Physicotechnical Institute, Ukrainian SSR Academy of Sciences. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 88, No. 3, pp. 358–375, September, 1991. 相似文献
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Conclusions The kinetics of the reaction of triethylphosphite with-acetoxyethylmethyl ketone was studied by infrared spectroscopy, and was found to be of the second order.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2614–2616, November, 1968. 相似文献
9.
The stability of boundary layers involving mass transfer described by a two-parameter family of Fockner-Scane (F-S) solutions is analyzed. An effective method of solving the boundary problem is proposed for the F-S equation. A determinant method is proposed for solving the stability equation. The critical values of the stability characteristics are found over a wide range of gradient and mass-transfer parameters. 相似文献
10.