arXiv subjects

Yu. M. Yevdokimov

Publications and source records attributed to Yu. M. Yevdokimov.

4 recordsLinked to original sources

arXiv2013

Magnetic properties of Gd3+ ions in the spatially distributed DNA molecules

Magnetic properties of DNA liquid-crystal dispersions are experimentally investigated by SQUID magnetometer. The magnetic susceptibility of pure DNA and DNA doped by La, and Gd is measured in the region 4.2-300 K. The total magnetic moment is represented as a sum of: the paramagnetic part and negative diamagnetic part. The number of paramagnetic Gd3+ ions is calculated in a good agreement with the number of phosphate complexes. The temperature dependence of magnetic susceptibility indicates the presence of interaction between Gd3+ magnetic moments, which is discussed in terms of long-range RKKY-type exchange in one-dimensional metals.

cond-mat.dis-nn↗

arXiv2000

Novel Cholesteric Phase in Dispersions of Nucleic Acids due to Polymeric Chelate Bridges

We consider cholesteric liquid-crystalline DNA dispersions, and show that polymeric (Dau-Cu) complexes, the so-called bridges, between pairs of DNA molecules may generate a super liquid-crystalline structure (BR-phase). The latter could have a layered spatial structure and an abnormal optical activity that could have a bearing upon the intense CD-band observed in DNA-dispersions.

cond-mat.soft↗

arXiv2000

Network of Hydrogen Bonds as a Medium for DNA Interaction in Solvents

We suggest that the DNA molecules could form the cholesteric phase owing to an interaction mediated by the network of the hydrogen bonds (H-network) in the solvent. The model admits of the dependence of the optical activity of the solution on the concentration of the PEG, and the change in the sense of the cholesteric twist due to the intercalation by the daunomicyn. Using the experimental data for the cholesteric phase of the DNA dispersion, we obtain a rough estimate for the energy given by our model, and show that it should be taken into account as well as the energy due to the steric repulsion, van der Waals, and electrostatic forces, generally used for studying the DNA molecules. The elastic constant of the H-network generating the interaction between the DNA molecules is determined by the energy due to the proton's vibration in the hydrogen bonds.

cond-mat.soft↗

arXiv1999

A Model for Double-Stranded Excitations of DNA

We calculate the spectrum of torsional vibrations of a double-stranded structure that models the double helix of the DNA. We come to the conclusion that within the framework of the model elementary excitations may display an asymmetry as regards their winding and direction of the propagation, depending on initial polarization. The asymmetry could have a bearing on processes that take place in molecules of the DNA.

cond-mat.soft↗