23.05.2017 Acknowledging publications

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

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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; σb= 992 MPa) and ductility (δ = 99%). Composite specimens with 2 wt.% graphene content after HPT at room temperature exhibits superior microhardness Hv = 6.45 GPa.

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17.05.2017 Acknowledging publications

Sensors and Actuators B: Chemical Volume 243, May 2017, Pages 338-345

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

Nd3+ single doped YVO4 nanoparticles for sub-tissue heating and thermal sensing in the second biological window

Sensors and Actuators B: Chemical Volume 243, May 2017, Pages 338-345

DOI: 10.1016/j.snb.2016.12.005

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The real controlled photothermal therapies demand designing multifunction systems capable of simultaneous heating and local thermal sensing. In this work, we report on neodymium doped yttrium vanadate nanoparticles acting as nanoheaters and nanothermometers at the same time under 808 nm single beam excitation. Heating is produced due to the nonradiative processes, whereas thermal sensing is obtained by luminescence intensity ratio between Stark sublevels lying in the second biological window. The influence of Nd3+ content on both heating and sensing abilities was studied. The potential application of YVO4:Nd3+ nanoparticles for deep tissue fluorescence bioimaging and controlled photothermal therapies is demonstrated.

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17.05.2017 Acknowledging publications

Journal of Inorganic and General Chemistry

Igor D. Strelnik, Elvira I. Musina, Svetlana N. Ignatieva, Anna S. Balueva, Tatiana P. Gerasimova, Sergey A. Katsyuba, Dmitry B. Krivolapov, Alexey B. Dobrynin, Christoph Bannwarth, Stefan Grimme, Ilya E. Kolesnikov, Andrey A. Karasik, Oleg G. Sinyashin

«Pyridyl Containing 1,5-Diaza-3,7-diphosphacyclooctanes as Bridging Ligands for Dinuclear Copper(I) Complexes»

Journal of Inorganic and General Chemistry

DOI: 10.1002/zaac.201700049

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1,5-bis(R)-3,7-bis[2-(pyridine-2′-yl)ethyl)-1,5-diaza-3,7-diphosphacyclooctanes 1 and 2 and their copper(I) complexes 3 and 4 were developed. The butterfly-shaped copper-iodide core and unusual P,N-chelate and P,P-bridged coordination mode of the heterocyclic ligand in the dinuclear complexes 3 and 4 were revealed. Complexes 3 and 4 display emission in green range of spectra, with lifetimes in a microsecond domain and quantum yields of luminescence in solid-state up to 38 %. Thermochromic effects found for the phosphorescence of 4 in solutions are ascribed to rigidochromism.

 

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27.04.2017 Acknowledging publications

Applied Surface Science 416 (2017) 988–995

A.A. Ionin, S.I. Kudryashov, A.O. Levchenko, L.V. Nguyen, I.N. Saraeva, A.A. Rudenko, E.I. Ageev, D.V. Potorochin, V.P. Veiko, E.V. Borisov, D.V. Pankin, D.A. Kirilenko, P.N. Brunkov

«Correlated topographic and structural modification on Si surface during multi-shot femtosecond laser exposures: Si nanopolymorphs as potential local structural nanomarkers»

Applied Surface Science 416 (2017) 988–995

DOI: 10.1016/j.apsusc.2017.04.215

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High-pressure Si-XII and Si-III nanocrystalline polymorphs, as well as amorphous Si phase, appear consequently during multi-shot femtosecond-laser exposure of crystalline Si wafer surface above its spallation threshold along with permanently developing quasi-regular surface texture (ripples, microcones), residual hydrostatic stresses and subsurface damage, which are characterized by scanning and transmission electron microscopy, as well as by Raman micro-spectroscopy. The consequent yields of these structural Si phases indicate not only their spatially different appearance, but also potentially enable to track nanoscale, transient laser-induced high-pressure, high-temperature physical processes – local variation of ablation mechanism and rate, pressurization/pressure release, melting/resolidification, amorphization, annealing – versus cumulative laser exposure and the related development of the surface topography.

 

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