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81.
V.V. Nemoshkalenko E.H. Brandt A.A. Kordyuk B.G. Nikitin 《Physica C: Superconductivity and its Applications》1990,170(5-6):481-485
The oscillation modes of a small spherical permanent magnet (1.7 mm diameter) above a flat high-Tc superconductor are investigated. From the attenuation and nonlinearity of the vertical oscillation we obtain the viscosity of the vortex lattice and the onset of hysteretic damping, which indicates depinning of flux lines. The shape of the potential well in which the magnet floats, rotates, and oscillates is found to depend on the magnetic history of the superconductor. 相似文献
82.
In the Hartree-Fock-Bogolyubov approximation, the cranking model is formulated with allowance for residual neutron-proton correlations whose interaction has a Gaussian form. The behavior of quasiparticle levels versus the frequency of rotation of the even-even isotopes 72–76Kr is investigated within this approach. 相似文献
83.
The effect of pressure in solutions of chitosan in carbonic acid with the AgNO3 precursor on the structure of cast nanocomposite films with silver nanoparticles has been studied for the first time. The size of silver nanoparticles can be controlled by varying pressure in carbonic acid. 相似文献
84.
I. R. Begishev A. K. Belikov I. S. Nikitin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(5):831-834
Flame propagation in a closed tube over mixtures of chloromethane and chlorine of different compositions following ignition by continuous UV radiation is studied. It is found that the rate of combustion in all mixtures except limiting ones grows along with the propagation of the flame front up to its maximum values at nearly 1/3 the tube length and then slows. In limiting mixtures, the speed’s behavior is completely different. It is greatest near the source of UV light and gradually slows with distance from the source. The high speed in the initial section is due to the effect of UV light. The temperature of combustion is lowest in limiting mixtures, and the rate of chlorine molecule photodissociation at this temperature is comparable to and even faster than that of their thermal dissociation. The light in these mixtures thus contributes substantially to the initiation of the chemical reaction. It is concluded that when limiting mixtures are ignited by UV pulses, the speed of flame propagation falls markedly as it proceeds without the influence of radiation, and the character of changes in the speed’s behavior becomes identical to those for other mixtures. 相似文献
85.
86.
O. A. Turanova E. V. Kal’dyaeva O. I. Gnezdilov S. I. Nikitin A. N. Turanov 《Russian Journal of General Chemistry》2010,80(2):258-262
Boron difluoride complexes possessing liquid crystalline and luminescent properties were synthesized for the first time on
the basis of non-mesogenic β-enaminoketones. 相似文献
87.
88.
Kirill Nikitin Helge Müller-Bunz Gérard Jaouen Michael J. McGlinchey 《Journal of organometallic chemistry》2010,695(4):595-608
The McMurry coupling of (tetraphenylcyclobutadiene)cobalt(cyclopentadienyl) ketones, (C4Ph4)Co[C5H4C(O)R], where R = Me, 3a, or Et, 3b, with a range of substituted benzophenones furnished a series of cobaltifens, organometallic analogues of tamoxifen whereby a phenyl ring has been replaced by an organo-cobalt sandwich moiety. These systems of the general formula (η4-C4Ph4)Co[η5-C5H4C(R)C(Ar)Ar′], where R = Me or Et, and Ar = Ar′ = p-C6H4X where X is OH, 2a and 2b, OMe, 2c and 2d, OBn, 2e and 2f, or O(CH2)2NMe2, 12a and 12b, and where Ar = C6H4OH and Ar′ = C6H4O(CH2)2NMe2, 2g and 2h, have been characterised by NMR spectroscopy and/or X-ray crystallography. The effect of 2a and 2b, 2g and 2h, and 12a and 12b on the growth of MCF-7 (hormone-dependent) and MDA-MB-231 (hormone-independent breast cancer cells) was studied. The dihydroxycobaltifens 2a and 2b exhibit a strong estrogenic effect on MCF-7 cells while the aminoalkyl-hydroxycobaltifens, 2g and 2h, were found to be only slightly cytotoxic on MDA-MB-231 cells (IC50 = 27.5 and 17 μM); surprisingly, however, the bis-(dimethylaminoethoxy)cobaltifens, 12a and 12b were shown to be highly cytotoxic towards both cell lines (IC50 = 3.8 and 2.5 μM). 相似文献
89.
A. B. Ustinov P. I. Kolkov A. A. Nikitin B. A. Kalinikos Y. K. Fetisov G. Srinivasan 《Technical Physics》2011,56(6):821-825
Planar phase shifters fabricated based on ferrite-ferroelectric layered structures are studied experimentally. The structures
served as waveguides for spin-electromagnetic waves, whose phase shift was controlled by both electric and magnetic fields.
The measurements were performed in the magnetic field range from 900 to 2100 Oe, which corresponds to operating frequencies
from 4.0 to 8.5 GHz, with 5- to 20-μm-thick yttrium-iron garnet ferrite films and 200- to 500-μm-thick barium-strontium titanate
ferroelectric plates. It is shown that the phase shift may exceed 180° and is a function of the magnetic and electric fields
and also of the thickness of the ferrite and ferroelectric layers. 相似文献
90.
F. N. Shamsetdinov L. Yu. Yarullin F. M. Gumerov F. R. Gabitov Z. I. Zaripov A. B. Remizov I. M. Kolyadko V. G. Nikitin A. K. Fakhreev D. I. Kamalova 《Russian Journal of Physical Chemistry B, Focus on Physics》2011,5(7):1167-1172
The influence of the pretreatment procedures with supercritical CO2 (SC-CO2) on the elemental composition of tealeaf is studied. Fourier-transform infrared absorption spectroscopy is used to examine
the effect of SC-CO2 on the structure of Chinese green tea and cellulose. 相似文献