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The kinetics of 1,4-cis polymerization of butadiene on a catalyst formed by reacting bis(-allyl) nickel with silica have been studied. The rate of polymerization is first order with respect to the monomer concentration. The apparent activation energy is 9.5±0.5 kcal/mol. The possible structure of the active center and the scheme of polymer chain growth have been discussed.
I,4- , -- . . 9,5±0,5 /. .
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Families of area preserving analytical maps, depending on a small parameter epsilon, are considered, with the case epsilon=0 corresponding to an integrable map. The asymptotic formulas for the splittings of separatrices are derived by the method of analytical continuation of the separatrices to the complex domain. The main terms of the asymptotics are exponentially small with respect to the size of the perturbation. As epsilon tends to zero, the intersection angle of the separatrices can oscillate. The exponent and the oscillatory multiplier of the asymptotic formulas are determined by the position of poles of the homoclinic (heteroclinic) orbit of the limiting flow. Pre-exponential coefficients in the asymptotic formulas contain a multiplier obtained by the numerical study of separatrices of "model" maps in the complex domain.  相似文献   
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The telomerization of butadiene with diethylamine with the formation of the tertiary amine (C2H5)2NC8H13 is catalyzed by Ni, Pd and Pt allyl halide complexes. Triphenylphosphine increases the activity of such catalysts. The rate of telomerization depends strongly on the [PPh3]/[M] ratio (M=Pd and Pt) and increases in the series of metals: Ni3H5PdCl)2 exceeds that of (-C3H5)2 Pd by more than two orders of magnitude.
Ni, Pd Pt (C2H5)2NC8H13. . [PPh3]/[M], M=Pd Pt, : Ni3H5PdCl)2 (-C3H5)2Pd.
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We prove for a one-dimensional system of classical particles with potential energy, $$U_{\alpha ,\gamma } = \sum\limits_n {\left[ {\alpha V(x_n ) + F(x_{n + 1} - x_n - \gamma )} \right]} $$ , the existence of such a smooth function γ(α), 0≦α≦α0(ω) that the system with potential energyU αγ(α) has the equilibrium state at the temperatureT=0. This is the incommensurate phase with the ratio of periods equal to the prescribed irrational number ω, badly approximated by rational ones. A simple geometric condition for the invariant curve of the corresponding dynamical system is established under which it is the support of the invariant measure minimizing Percival's energy functional.  相似文献   
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It is shown that the hypothesis of transversality formulated by V. I. Arnol'd is not satisfied for all domains. Examples are presented of domains for which the variations of the eigenvalues of the Laplace operator for small perturbations of the domain are linearly dependent.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 51, pp. 134–137, 1975.  相似文献   
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