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71.
Petr I. Nikitin Petr M. Vetoshko Tatiana I. Ksenevich 《Journal of magnetism and magnetic materials》2007
A new type of biosensor has been developed based on detection of nanosized superparamagnetic particles that serve as labels in bioreactions. The method is based on non-linear magnetic material detection by a magnetic field having components at two frequencies f1 and f2. The response is measured at the combinatorial frequencies fi=mf1+nf2, where m and n are integers, e.g., fi=f1±2f2. Several highly sensitive readers of superparamagnetic particles have been designed and used for development of various formats of immunoassays, including those compatible with immunoconcentration and magnetic enrichment of antigens. 相似文献
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D. D. Ri V. G. Mansurov A. Yu. Nikitin A. K. Gutakovskii K. S. Zhuravlev P. Tronc 《JETP Letters》2005,81(2):62-65
The photoluminescence (PL) of GaN quantum dots in an AlN matrix is studied. It is found that the maximum of the PL line does not shift when the laser excitation power varies. The transient PL spectra indicate that the quenching kinetics is nonexponential and the quenching law depends on the spectral range. The experimental data are explained in the framework of a model taking into account the strong built-in electric field in wurtzite structures and the transport of charge carriers between them. 相似文献
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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
78.
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
79.
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
80.
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