Publications by authors named "Sergey Maksimenko"

Water pollution is nowadays a global problem and the effective detection of pollutants is of fundamental importance. Herein, a facile, efficient, robust, and rapid (response time < 2 min) method for the determination of important quinone-based industrial pollutants such as hydroquinone and benzoquinone is reported. The recognition method is based on the use of screen-printed electrodes as sensing platforms, enhanced with carbon-based nanomaterials.

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We propose an original technique for the fabrication of terahertz (THz) metasurfaces comprising a 3D printed regular array of polymer hemispheres covered with a thin conductive layer. We demonstrate that the deposition of a thin metal layer onto polymer hemispheres suppresses the THz reflectivity to almost zero, while the frequency range of such a suppression can be considerably broadened by enhancing the structure with graphene. Scaling up of the proposed technique makes it possible to tailor the electromagnetic responses of metasurfaces and allows for the fabrication of various components of THz photonics.

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Article Synopsis
  • Researchers created composite materials with high levels of a specific ferroelectric compound (0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3) mixed into phosphate-bonded ceramics under varying pressures.
  • All samples displayed a consistent distribution of the active ferroelectric phase and maintained thermal stability up to 900 K.
  • The study found that the density of these composites varies in a non-linear way with pressure, with increased density leading to higher dielectric permittivity and strong piezoelectric properties.
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The patterning of arrays of aligned multi-walled carbon nanotubes (MWCNTs) allows creating metastructures for terahertz (THz) applications. Here, the strips and columns from MWCNTs vertically grown on silicon substrates are prepared using CO laser treatment. The tops of the patterned arrays are flat when the laser power is between 15 and 22 W, and craters appear there with increasing power.

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The composites and thin films comprising individual single-walled carbon nanotubes with a polymer coating (p-CNTs) have been prepared and their electromagnetic responses have been studied in a wide range from low-frequency (25-10 Hz) up to the infrared region. In spite of the high volume fraction of the nanotubes (up to 3.3%), the polymer coating prevents direct p-CNT contacts and the formation of the percolation network in those composites, so that p-CNTs interact only via the electromagnetic coupling.

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This paper investigates the electrical properties in the microwave range of a contact made by graphene nanoplatelets. The final goal is that of estimating the range of values for the equivalent electrical complex permittivity of a contact obtained by integrating low-cost graphene in the form of nanoplatelets (GNPs) into a high-frequency electrical circuit. To this end, a microstrip-like circuit is designed and realized, where the graphene nanoplatelets are self-assembled into a gap between two copper electrodes.

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Strong vibrational coherent anti-Stokes Raman scattering (CARS) signal was observed in single-wall carbon nanotubes (SWCNTs) having three different average diameters (about 0.8 nm, 1.1 nm and 1.

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Article Synopsis
  • The study explores the dielectric properties of PMMA composites filled with multiwalled carbon nanotubes (MWCNT) that have different outer diameters.
  • It finds that composites with thicker nanotubes have a lower percolation threshold and higher dielectric permittivity below this threshold.
  • The research highlights that the temperature dependence of the dielectric permittivity is influenced by beta relaxation in the PMMA matrix, with thicker nanotubes increasing the energy barrier for PMMA molecular rotation.
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We analyzed the electromagnetic (EM) shielding effectiveness in the Ka band (26 to 37 GHz) of highly amorphous nanometrically thin pyrolytic carbon (PyC) films with lateral dimensions of 7.2 × 3.4 mm2, which consists of randomly oriented and intertwined graphene flakes with a typical size of a few nanometers.

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Electromagnetic absorption and subsequent heating of nanoparticle solutions and simple NaCl ionic solutions is examined for biomedical applications in the radiofrequency range at 13.56 MHz. It is shown via both theory and experiment that for in vitro measurements the shape of the solution container plays a major role in absorption and heating.

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