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Vestnik SPbSU. Physics and Chemistry Volume 4 (62), issue 1, Pages 34–40

Unksov I.N., Bakulev V.M., Kasyanenko N.A.

Interaction of triethanolamine with high molecular DNA and its influence on formation of surfactant—DNA complexes

Vestnik SPbSU. Physics and Chemistry Volume 4 (62), issue 1, Pages 34–40

Effect of triethanolamine (TEA) on high molecular calf thymus DNA in aqueous solution was studied by fluorescent spectroscopy and viscometry. It was shown that TEA prevents the interaction of the fluorescent dye DAPI with phosphate groups, but does not affect binding of the dye to the minor groove of DNA. The presence of TEA in solution does not induce any changes in the secondary structure of DNA. We estimated the decrease of the volume of DNA molecular coil in solution, which is induced by TEA. The destruction of DNA—surfactant complexes formed in solution was observed after the addition of TEA.

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Journal of Luminescence 192 (2017) 40–46

I.E. Kolesnikov, A.A. Kalinichev, M.A. Kurochkin, D.V. Mamonova, E.Yu. Kolesnikov, A.V. Kurochkin, E. Lähderanta, M.D. Mikhailov

«New strategy for thermal sensitivity enhancement of Nd³⁺-based ratiometric luminescence thermometers»

Journal of Luminescence 192 (2017) 40–46

DOI: 10.1016/j.jlumin.2017.06.024

Accurate luminescence thermal sensing using nanophosphors that operate within biological windows is of great interest in bio- and nanomedicine. Here, we show that Nd³⁺-doped YVO₄ NPs can act as nanothermometers in the second biological window upon 808 nm excitation. Significant enhancement of thermal sensitivity and temperature resolution was achieved by optimal choice of wavelengths for ratiometric thermal calibration. It was concluded that thermal calibration should be calculated using integral intensities. The obtained temperature uncertainty together with the emission and excitation lying in the biological windows open the venue to the possible application of Nd³⁺-doped YVO₄ NPs for real time sub-tissue luminescence thermal sensing with a subdegree resolution.

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On June 2, 2017, the delegation of the Harbin Polytechnic University visited the RC OLMIV, accompanied by the director of the SPSU Research park Mikushev S.V.

Members of the delegation:

- Zhou Yu (rector of Harbin Polytechnic University)

- Zhao Hongzhui (Head of the Law Institute of Harbin Polytechnic University)

- Mei Wenzhang (head of the department for work with Russia and CIS countries).

In the conclusion of the meeting prof. Tunik S.P. spoke to the guests about the work of his scientific group.

The meeting was attended by Assoc.prof. Gracheva E.V. and Assoc.prof. Manshina A. A.

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Progress in Photon Science, Chapter 25, Pages 253-261

Yury Tver’yanovich, S. Fokina and E. Borisov

Super-Ionic Nano-Composite Solid Electrolytes Prepared by Laser Ablation

Progress in Photon Science, Chapter 25, Pages 253-261

DOI: 10.1007/978-3-319-52431-3_25

Using the laser ablation method, AgI stoichiometric compound films, (GeSe₂)₃₀(Sb₂Se₃)₃₀(AgI)₄₀ glass films, and films comprised of alternating layers of AgI and the glass were obtained. Individual layer thickness amounts to 10 nm, and the total number of layers is about 100. Film conductivity measurements were carried out during several cycles of heating up to 200 °C and cooling to room temperature. It was established that after three cycles of thermal processing specific lateral conductivity of the film is equal to 0.3 S cm⁻¹ and conductivity activation energy is equal to 0.07 eV at room temperature.

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REVIEWS  ON  ADVANCED  MATERIALS   SCIENCE Volume 50, No. 1, Pages 13-23

I.Yu. Archakov, V.U. Kazykhanov, V.G. Konakov, O.Yu. Kurapova, A.E. Medvedev, M.Yu. Murashkin, N.N. Novik, I. A. Ovidko, E. N. Solovyeva and R.Z. Valiev

MICROSTRUCTURE AND MECHANICAL CHARACTERISTICS OF NANOSTRUCTURED NICKEL-GRAPHENE COMPOSITES PROCESSED BY HIGH PRESSURE TORSION

REVIEWS  ON  ADVANCED  MATERIALS   SCIENCE Volume 50, No. 1, Pages 13-23

This paper presents data on fabrication of “nickel-graphene-graphite” bulk composites using powder metallurgy methods combined with the high energy ball milling. The composites were then processed by high pressure torsion (HPT) at temperatures of 23 and 200 °C. This treatment gives rise to the formation of new “nanostructured nickel-graphene” composites. The phase composition of the new composite specimens was examined by X-ray diffraction. Raman spectroscopy proved graphite-to-graphene conversion under mechanical treatments. The microstructure of the new composite specimens was investigated by scanning electron and transmission electron microscopy methods. Composite specimens after HPT at temperature of 200 °C demonstrate the optimal combination of strength (σ₀₂= 923 MPa; σ_b= 992 MPa) and ductility (δ = 99%). Composite specimens with 2 wt.% graphene content after HPT at room temperature exhibits superior microhardness H_v = 6.45 GPa.