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11.
V. V. Saraev P. B. Kraikivskii D. A. Matveev A. S. Kuzakov A. I. Vil’ms A. A. Fedonina 《Russian Journal of Coordination Chemistry》2008,34(6):438-442
The interaction of Ni(II) bis-tetrafluoroborate complexes [Ni(Dppe)2](BF4)2 and [Ni(CH3CN)6](BF4)2 (where Dppe = 1,2-bis(diphenylphosphino)ethane)) with Ni(0) phosphine complexes Ni(Dppe)2 and Ni(PPh3)4 in 1 : 1 mixture of toluene-acetonitrile was studied by the EPR method. The counter-disproportionation was shown to occur in a solution between the cationic Ni(II) complexes and the Ni(0) complexes to give Ni(I) complexes almost in quantitative amounts. The structures of the cationic Ni(I) complexes obtained were found to depend on both the solvent nature and the presence of a free phosphine in a solution. 相似文献
12.
P. S. Vinnitskii K. A. Kuzakov Yu. V. Popov C. Dall Cappello 《Moscow University Physics Bulletin》2008,63(1):28-32
The physical series of the perturbation theory is defined for the case of multiparticle Coulomb scattering and the results of numerical calculations are given for the contribution of higher Born terms to the amplitude of the electron-induced quasielastic knockout of an electron from the hydrogen atom. The purpose is to find the range of applicability of the basic theory of such reactions. 相似文献
13.
An analytical iterative procedure has been established to determine the amplitude of a laser beam propagating through an active
medium. The treatment is valid for both homogeneous and inhomogeneous broadening, and for arbitrary inhomogeneities of the
parameters characterizing the active medium, namely, the refractive index, the small-signal gain and the saturation intensity.
After a supplementary approximation, a thin-sheet gain approach is derived from the first iteration. The formalism enables
us to provide analytical criteria for evaluating both the accuracy of each iteration and the propagation distances for which
the thin-sheet solution can be used.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
14.
From pulsed phosphorescence microwave double resonance experiments it is established that electron tunneling between FA and F+ centers in CaO occurs from FA centers in the excited 3A1 state. Only the radiative sub-levels within this 3A1 state act as precursor states in the electron transfer process. The tunneling rate at 1.2 K is determined to be 1.5±0.2s-1. 相似文献
15.
Background
The involvement of astrocyte water channel aquaporin-4 (AQP4) in autoimmune diseases of the central nervous system has been suggested following the identification of AQP4 autoantibodies in neuromyelitis optica, an inflammatory demyelinating disease. 相似文献16.
P. B. Kraikivskii V. V. Saraev V. V. Bocharova G. V. Romanenko D. A. Matveev S. K. Petrovskii A. S. Kuzakov 《Russian Journal of Coordination Chemistry》2012,38(6):416-425
A reaction of Ni(Allyl)2 with bis(2,6-diisopropylphenyl)diazabutadiene gave an imino amide allyl nickel(II) complex (I). Complicated rearrangements of the imino amide ligand in the coordination sphere of complex I spontaneously yielded a paramagnetic Ni(I) ??-allyl complex as a final reaction product. The nickel complexes produced in this system were studied by EPR, IR, and 2D NMR spectroscopy and mass spectrometry. Structure I was examined by X-ray diffraction. 相似文献
17.
MARTI´NEZ C. Encinas-Sanz F. Serna J. MEJI´AS P. M. MARTI´NEZ-HERRERO R. 《Optical and Quantum Electronics》1997,29(9):923-931
A simple analytical model is proposed to describe the transversal spatial structure of a tridimensional rotationally symmetric
pulsed beam. The spatial behaviour of the pulse amplitude is shown to be linked to its (measurable) second- and higher-order
intensity moments, namely, beam width, quality parameter and kurtosis. As an illustrative experimental example, this model
has been applied to high-quality TEA CO2 laser pulses.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
18.
Let pn be the nth prime. Then this paper is concerned with provingthe following result on the distribution of consecutive primes. The exponent of x in this theorem improves on the work of Heath-Brownwho proved (1) with exponent . Under the Riemann hypothesisone can prove (1) with exponent .The proof of the theorem startswith the Heath-BrownLinnik identity which leads to aformula giving the number of primes in an interval in termsof coefficients of certain Dirichlet series. I then estimatethe coefficients by using, among other things, the informationwhich can be gained from Montgomery's mean value theorem andHuxley's version of the Hal' asz lemma. Furthermore, by usingfamiliar sieve arguments I am able to discard some of the coefficientsallowing us to gain an improvement over the previous resultof Heath-Brown. 1991 Mathematics Subject Classification: 11N05. 相似文献
19.
A synthesis of nicotyrine ( 9 ), and hence formally racemic nicotine, was carried out by elaboration of the 1 : 1 adduct 2 of cycloocta‐1,5‐diene and chlorosulfonyl isocyanate (ClSO2? NCO). Transformation of adduct 2 into carbamate 4 was followed by ozonolysis, tosylation, and NaH treatment, which led to pyrrolidinylpiperidinone 6 . LiAlH4 Reduction, debenzylation, and aromatization yielded 2 . 相似文献
20.
A. V. Kuznetsov A. S. Kuzakov E. F. Martynovich 《Bulletin of the Russian Academy of Sciences: Physics》2016,80(1):64-67
The formation of fluorescent channels with color centers in LiF crystals under the action of the multiple filamentation of femtosecond laser pulses is studied experimentally and theoretically for pulse powers around four orders of magnitude higher than the critical self-focusing value. 相似文献