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Gdańsk University of Technology

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Publications from the year 2020

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  • Structural, magnetic and spectral properties of tetrahedral cobalt(II) silanethiolates: a variety of structures and manifestation of field-induced slow magnetic relaxation
    • Daria Kowalkowska-Zedler
    • Anna Dołęga
    • Natalia Nedelko
    • Renata Łyszczek
    • Pavlo Aleshkevych
    • Iraida Demchenko
    • Justyna Łuczak
    • Anna Ślawska-waniewska
    • Agnieszka Pladzyk
    2020 DALTON TRANSACTIONS

    Blue crystals of five heteroleptic cobalt(II) silanethiolates 1–5 have been obtained by the reaction of [Co{SSi (tBuO)3}2(NH3)]2 with aminopyridines and aminomethylpyridines at an appropriate molar ratio and their structural, spectral, thermal and magnetic properties have been established and described. All complexes 1–5 contain Co(II) ions in a tetrahedral CoN2S2 environment formed by (tBuO)3SiS− residues and pyridines and present variable structures. Complexes 1–3 are mononuclear [Co{SSi(tBuO)3}2(L1)2] (L1 = 2-aminopyridine 2AP, 3-aminopyridine 3AP, and 4-aminopyridine 4AP). The application of 3AMP and 4AMP (3-aminomethylpyridine and 4-aminomethylpyridine) allows either dinuclear complex 4 [Co{SSi(tBuO)3}2(μ-3AMP)]2 or 1D coordination polymer 5 with the formula of [Co{SSi(tBuO)3}2(μ-4AMP)]n to be obtained. The molecular structures of 1–5 were determined by single-crystal X-ray and powder diffraction, UV-vis and FTIR spectrocopy for solid samples and their thermal properties were characterized by TG-DSC and TG-FTIR methods. The dc and ac magnetic and EPR studies of polycrystalline samples have been performed. For all complexes, the obtained data show a behavior typical of paramagnetic high–spin Co(II) ions in a tetrahedral geometry, with a considerable contribution of the ZFS effect in a low temperature range. All complexes were also probed for SIM behavior. The modeling of the magnetic and EPR data was done for samples 1, 3, 4 and 5 to estimate ZFS parameters. The obtained results imply a negative value of the axial parameter D in complex 4 and positive D values for the rest of the compounds. A comparative magneto-structural analysis of complexes 4 and 5 points to the high sensitivity of the single-ion magnetic anisotropy of tetrahedral Co (II) complexes to subtle changes in the first and second coordination spheres of Co(II) ions.

  • Structural Properties and Water Uptake of SrTi1−xFexO3−x/2−δ
    • Tadeusz Miruszewski
    • Kacper Dzierzgowski
    • Piotr Winiarz
    • Sebastian Wachowski
    • Aleksandra Mielewczyk-Gryń
    • Maria Gazda
    2020 Full text Materials

    In this work, Fe-doped strontium titanate SrTi1−xFexO3−x/2−δ, for x = 0–1 (STFx), has been fabricated and studied. The structure and microstructure analysis showed that the Fe amount in SrTi1−xFexO3−x/2−δ has a great influence on the lattice parameter and microstructure, including the porosity and grain size. Oxygen nonstoichiometry studies performed by thermogravimetry at different atmospheres showed that the Fe-rich compositions (x > 0.3) exhibit higher oxygen vacancies concentration of the order of magnitude 1022–1023 cm−3. The proton uptake investigations have been done using thermogravimetry in wet conditions, and the results showed that the compositions with x < 0.5 exhibit hydrogenation redox reactions. Proton concentration at 400 °C depends on the Fe content and was estimated to be 1.0 × 10−2 mol/mol for SrTi0.9Fe0.1O2.95 and 1.8 × 10−5 mol/mol for SrTi0.5Fe0.5O2.75. Above 20 mol% of iron content, a significant drop of proton molar concentrations at 400 °C was observed. This is related to the stronger overlapping of Fe and O orbitals after reaching the percolation level of approximately 30 mol% of the iron in SrTi1−xFexO3−x/2−δ. The relation between the proton concentration and Fe dopant content has been discussed in relation to the B-site average electronegativity, oxygen nonstoichiometry, and electronic structure.

  • Structure and water uptake in BaLnCo2O6−δ (Ln =La, Pr, Nd, Sm, Gd, Tb and Dy)
    • Sebastian Wachowski
    • Iga Szpunar
    • Magnus H. Sorby
    • Aleksandra Mielewczyk-Gryń
    • Maria Balaguer
    • Corneliu Ghica
    • Marian Cosmin Istrate
    • Maria Gazda
    • Anette E. Gunnæs
    • José M Serra
    • Truls Norby
    • Ragnar Strandbakke
    2020 Full text ACTA MATERIALIA

    The structure of BaLnCo2O6-δ (Ln =La, Pr, Nd, Sm, Gd, Tb and Dy) was studied by the means of synchrotron radiation powder X-ray diffraction, neutron powder diffraction and Transmission Electron Microscopy (TEM), while water uptake properties were analysed with the use of thermogravimetry (TG) and water adsorption isotherms. The structure refinement revealed that the dominant phase in all compositions was orthorhombic with an ordering of the A-site cations along the c-axis and ordering of oxygen vacancies along the b-axis, which was also directly evidenced by TEM. It was shown that both unit cell volume and average Co-oxidation state at room temperature decrease linearly with decreasing Ln radius. TG water uptake experiments in humidified N2–O2 gas mixture at 300 °C revealed that among all compositions, only BaLaCo2O6-δ and BaGdCo2O6-δ exhibit significant water uptake. Surface water adsorption studies showed that the α, a normalised parameter reflecting the surface hydrophilicity, mostly independently of Ln radius was close to 0.5, which means that the surface is neither hydrophobic nor hydrophilic. The results indicated that water uptake observed at 300 °C is a bulk process, which cannot be described by standard hydration/hydrogenation reaction and it is related to the layered structure of the perovskite lattice and characteristic to La or Gd being present in the lattice.

  • Structure of the interlayer between Au thin film and Si-substrate: Molecular Dynamics simulations
    • Valeriy Plechystyy
    • Ihor Shtablavyi
    • Szymon Winczewski
    • Kamil Rybacki
    • Stepan Mudry
    • Jarosław Rybicki
    2020 Full text Materials Research Express

    Interaction between 2, 3, 5 and 7 atomic layers of gold and a (111) silicon surface was investigated with the molecular dynamics simulation method. The simulation of the diffusion interaction between gold and silicon in the temperature range 425-925 K has been carried out. The peculiarities of the concentration changes of the interacting components and the atomic density at the boundary of two phases in the direction perpendicular to the crystalline surface were established. By means the formalism of quasi two dimensional partial pair correlation functions the atomic structure of the diffusion region was analyzed. The formation of the alloy of eutectic composition within the gold-silicon interlayer was established. It was shown that the inter-phase mixing in various temperature intervals occurred according to different diffusion mechanisms

  • Students’ soft urban planning skills and local development are the benefits from the Fair of Good Practice. Small cities - big challengesprogramme
    • Karolina Krośnicka
    2020 Full text World Transactions on Engineering and Technology Education

    The urban planner in practice needs soft skills when dealing with public consultations connected to local development plans. To improve the abilities of architecture and urban planning students to discuss solutions and to support the development of local public spaces of small towns in the Pomeranian voivodeship ( province) in Poland, the Fair of Good Practice. Small cities - big challenges programme was developed. It was organised as a series of four projects, each in the form of an urban design studio, and was implemented in the Faculty of Architecture at Gdańsk University of Technology (FA-GUT), between 2016 and 2018. The programme covered urban design topics in two towns of the Pomeranian voivodeship (Rumia and Reda). It was an example of involvement in teaching of different stakeholders connected with urban planning, with an intergenerational exchange of knowledge and support for public participation.

  • STUDY OF CuO AND V2O5 EFFECT ON IR SPECTRA OF POLYCRYSTALLINE BISMUTH NIOBATE
    • Iwona Kuźniarska-Biernacka
    • Agata Lisińska-Czekaj
    • Dionizy Czekaj
    2020 Full text ARCHIVES OF METALLURGY AND MATERIALS

    Bismuth niobate (BiNbO4) ceramics were fabricated by mixed oxide method and sintered by presureless sintering method. BiNbO4 ceramics doped with V2O5 additive in amount 0.125 wt%, 0.250 wt% and 1 wt% of was sintered at T = 910°C whereas BiNbO4 ceramics doped with 2 wt% of CuO additive was sintered at T = 890°C and T = 910°C. It was found that V2O5 additive improved morphology of the ceramic samples. However, the chemical composition of BiNbO4 ceramics in relation to bismuth oxide and niobium oxide manifested a tendency of lack of Bi2O3 component. Absorption bands for the BiNbO4 compound were identified. FTIR band positions associated with NbO6 octahedra suggested that the crystal structure changes after V2O5 incorporation.

  • Study of oxygen electrode reactions on symmetrical porous SrTi0.30Fe0.70O3-δ electrodes on Ce0.8Gd0.2O1.9 electrolyte at 800 °C–500 °C
    • Aleksander Mroziński
    • Sebastian Molin
    • Piotr Jasiński
    2020 Full text ELECTROCHIMICA ACTA

    Iron doped strontium titanates (SrTi1-xFexO3-δ) are an interesting mixed ionic-electronic conductor model used to study basic oxygen reduction/oxidation reactions. In this work, we performed an impedance spectroscopy study on symmetrical porous SrTi0.30Fe0.70O3-δ (STF70) electrodes on a ceriabased electrolyte. The sample was measured in varying oxygen concentration: from 0.3% to 100% in 800 °C - 500 °C temperature range. Low polarisation resistance (e.g. <125 mΩ cm2 at 600 °C in the air) values were obtained, showing an overall high performance of the STF70 electrode. Impedance data analysis was assisted by the distribution of relaxation times method, which allowed an equivalent electrical circuit to be proposed comprising of two resistance/constant phase element sub-circuits connected in series. The medium frequency contribution, with a characteristic frequency of ~2000 Hz at 800 °C in air, originates most probably from possible surface diffusion followed by charge transfer reaction limitation, whereas the lower frequency contribution (characteristic frequency <10 Hz) is due to gas-phase diffusion.

  • Study of railway traffic safety based on the railway track condition monitoring system
    • S Kliuiev
    • Ievgen Medvediev
    • N Khalipova
    2020

    The solution to the problem of monitoring the railway track, as well as potentially dangerous objects and phenomena in the adjacent territories, is determined by the need to implement increased requirements for traffic safety (primarily to the geometric parameters of the devices of a long railway track under construction and functioning load-bearing highways), prevention of technological disasters and large-scale negative effects of natural phenomena on the railways. The continuous process of integrating methods and means of monitoring and preventing emergencies into a single information management system is shown. The possibility of determining a dynamic model of the adverse effect of the train on the track and the most unfavorable for the track train and traction parameters, which must be avoided when forming trains in this section, is established. Three key factors are formulated, the use of which will reduce the negative impact on the track from trains. The concept of information technology improvement of the monitoring system for potentially dangerous sections of the railway on the basis of new innovative technologies has been developed.

  • Study of the Effect of Filling Thermoplastic Medical Polyurethane with PVA, PLA or Diatomite on the Relaxation Times Distributions of 1H NMR
    • Justyna Kucińska-Lipka
    • Nikolay Sinyavsky
    • I. Mershiev I.
    • Józef Haponiuk
    2020 Full text APPLIED MAGNETIC RESONANCE

    In this work, to characterize the mobility of diferent sections of the macromole‑ cules of polyurethane (PUR), polyvinyl alcohol (PVA), and polylactic acid (PLA), as well as the density of crosslinks of the polymer chains when using fllers, we used the distributions of spin–lattice and spin–spin relaxation times for the protons. It is shown that the rigidity of the thermoplastic polymers depends on the sizes of the granules of the diatomite fller, which can embed in the polymer matrix. Conse‑ quently, relaxation times are reduced. If PLA is the fller of PUR, the dynamics of the molecules in the chains and the spin–spin interaction of the protons are afected by the crosslinking of PUR by PLA. An increase in crosslinks density reduces the rate of polymer degradation.

  • Study on applicability of two modal identification techniques in irrelevant cases
    • Agnieszka Tomaszewska
    • Marek Szafrański
    2020 Full text Archives of Civil and Mechanical Engineering

    Study on applicability of two modal identification techniques in irrelevant cases is made in this paper. The following techniques are considered: Peak Picking based on correlation analysis (PP-CA), dedicated for ambient vibrations and Eigensystem Realization Algorithm (ERA), formulated for free decay vibrations investigation. Irrelevant cases are found when analyzed signals are different than recommended to a given technique. The study is conducted on examples of two real structures: masonry tower and steel railway bridge. Both cases are diverse in age, material, excitation and vibrations energy. The signals measured on the tower are suitable for the PP-CA technique (ambient vibrations), while the signals measured on the bridge are suitable for the ERA (free decay vibrations). However, both methods have been applied to both systems. Natural frequencies, mode shapes and damping ratios are identified and the effectiveness of the irrelevant technique is assessed in relation to the results obtained by the relevant method in each case.

  • Study on Methods to Control Interstory Deflections
    • Seyed Mohammad Khatami
    • Hosein Naderpour
    • Seyed Mohammad Nazem Razavi
    • Rui Barros
    • Anna Jakubczyk-Gałczyńska
    • Robert Jankowski
    2020 Full text Geosciences

    One of the possibilities to prevent building pounding between two adjacent structures is to consider appropriate in-between separation distance. Another approach might be focused on controlling the relative displacements during seismic excitations. Although the majority of building codes around the world recommend the use of some equations of various distances between structures to avoid pounding; a lot of reports after earthquakes have obviously shown that safety situation or economic consideration is not always provided due to the collisions between buildings and high cost of land; respectively. The aim of the present paper is to focus the analysis on the properties of structures and conduct an in-depth analysis of available methods to control interstory deflections so as to prevent pounding. For this purpose, a numerical lumped mass model of the five-story building has been considered and its response under different earthquake records has been investigated. Firstly, the influence of the change in structural properties (story stiffness; mass and damping) has been examined. Then the application of tuned mass damper, base isolation and base isolation with rubber bumpers has been considered. The results of comparative analyses clearly indicate that using base isolation, with the addition of bumpers, can be selected as the best method to control building deflections and decrease absolute lateral displacement between two buildings so as to prevent their pounding during earthquakes.

  • Study on Polymer Elements for Mitigation of Earthquake-Induced Pounding Between Buildings in Complex Arrangements
    • Barbara Sołtysik
    • Tomasz Falborski
    • Robert Jankowski
    2020

    Pounding between neighboring structures during seismic events has been revealed as one of the most commonly observed reasons for severe damage or even total collapse of the adjacent buildings. Therefore, pounding effects have recently become an issue of great interest of many numerical and experimental investigations in many earthquake-prone regions of the world. It has also been observed that the differences in dynamic characteristics is the key reason leading to interaction between colliding, insufficiently separated structures. The problem is much more complicated for complex arrangements of structures, for example, in the case of collisions between few structures in a row. A lot of different approaches have been considered to mitigate earthquake-induced structural pounding. One method is based on placing between the structures some viscoelastic elements acting as bumpers. Another one is stiff linking the structures. It allows the forces to be transmitted between buildings and thus eliminate undesired interactions. The aim of this paper is to present the results of experimental research focused on mitigation of pounding between buildings in complex arrangements by using polymer elements installed between structures. In the present study, three steel models characterized by various dynamic properties and different in-between distances were investigated. Additional masses were mounted at the top of each model in order to obtain different dynamic characteristics. The unidirectional shaking table, available at the Gdansk University of Technology (Poland), was employed to conduct this study. Experimental models were mounted to shaking table platform. The results of the study explicitly show that the approach of using polymer elements can be an effective pounding mitigation technique in the case of complex arrangement of buildings. It may partially or fully prevent from damaging collisions between adjacent buildings during seismic events. It also enhances the dynamic response leading to the reduction in lateral vibrations under different strong ground excitations.

  • Study on the Coastline Evolution in Sopot (2008–2018) Based on Landsat Satellite Imagery
    • Mariusz Specht
    • Cezary Specht
    • Oktawia Lewicka
    • Artur Makar
    • Paweł Burdziakowski
    • Paweł Dąbrowski
    2020 Full text Journal of Marine Science and Engineering

    The coastline is the boundary between the water surface in a reservoir or watercourse and the land, which is characterised by high instability and functional diversity. For these reasons, research on coastal monitoring has been conducted for several decades. Currently, satellite images performed with synthetic aperture radars (SARs) are used to determine its course and variability together with high-resolution multispectral imagery from satellites such as IKONOS, QuickBird, and WorldView, or moderate-resolution multispectral images from Landsat satellites. This paper analysed the coastline variability in Sopot (2008–2018) based on Landsat satellite imagery. Furthermore, based on multispectral images obtained, it was determined how the beach surface in Sopot changed. Research has shown that the coastline keeps moving away from the land every year. This was particularly noticeable between 2008 and 2018 when the coastline moved on average 19.1 m towards the Baltic Sea. Moreover, it was observed that the area of the sandy beach in Sopot increased by 14 170.6 m2, which translates into an increase of 24.7% compared to 2008. The probable cause of the continuous coastline shift towards the sea and the increase of the beach surface is the oceanographic phenomenon called tombolo, which occurred in this area as a result of the construction of a yacht marina near the coast.

  • Study on the Structure-Property Dependences of Rigid PUR-PIR Foams Obtained from Marine Biomass-Based Biopolyol
    • Paulina Kosmela
    • Aleksander Hejna
    • Jan Suchorzewski
    • Łukasz Piszczyk
    • Józef Haponiuk
    2020 Full text Materials

    The paper describes the preparation and characterization of rigid polyurethane-polyisocyanurate (PUR-PIR) foams obtained with biopolyol synthesized in the process of liquefaction of biomass from the Baltic Sea. The obtained foams differed in the content of biopolyol in polyol mixture (0–30 wt%) and the isocyanate index (IISO = 200, 250, and 300). The prepared foams were characterized in terms of processing parameters (processing times, synthesis temperature), physical (sol fraction content, apparent density) and chemical structure (Fourier transform infrared spectroscopy), microstructure (computer microtomography), as well as mechanical (compressive strength, dynamic mechanical analysis), and thermal properties (thermogravimetric analysis, thermal conductivity coefficient). The influence of biopolyol and IISO content on the above properties was determined. The addition of up to 30 wt% of biopolyol increased the reactivity of the polyol mixture, and the obtained foams showed enhanced mechanical, thermal, and insulating properties compared to foams prepared solely with petrochemical polyol. The addition of up to 30 wt% of biopolyol did not significantly affect the chemical structure and average cell size. With the increase in IISO, a slight decrease in processing times and mechanical properties was observed. As expected, foams with higher IISO exhibited a higher relative concentration of polyisocyanurate groups in their chemical structure, which was confirmed using principal component analysis (PCA).

  • Studying the Effect of Working Conditions on WEDM Machining Performance of Super Alloy Inconel 617
    • Stefan Dzionk
    • Mieczysław Siemiątkowski
    2020 Full text Machines

    Wire electrical discharge machining (WEDM) has been for many years a precise and efficient non-conventional manufacturing solution in various industrial applications, mostly involving the use of hard-to machine materials like, among other, the Inconel super alloys. The focus of the present study is on exploring the effect of selected control parameters, including pulse duration, pulse-off time and the dielectric flow pressure on the WEDM process performance characteristics of Inconel 617 material such, as: volumetric material removal rate (MRR), the dimensional accuracy of cutting (reflected by the kerf width) and surface roughness (SR). The research experiment has been designed and carried out using the response surface methodology (RSM) accordingly with the Box-Behnken design scheme. The results of experiments derived in the form of a fitted regression model have been subjected to the analysis of variance (Anova) tests. Thus, the variable process parameters and the relevant interactions between them characterized by a significant influence on the values of the derived output responses could be explicitly determined.

  • Subcritical Thermodynamic Cycles with Organic Medium and Isothermal Expansion
    • Krzysztof Kosowski
    • Marian Piwowarski
    2020 Full text ENERGIES

    The efffciencies of the Organic Rankine Cycle (ORC) are not very high and only very seldom do they exceed 20%. The increase and optimization of initial parameters and certain modifications of the thermodynamic cycle make it possible to overcome these drawbacks. A new modified cycle has been described and analyzed in detail in the paper. Similarly to the Ericsson cycle for gas turbines, isothermal expansion in the turbine is suggested for the power plant with organic media. The new cycle and the typical ORC power plants have the same block diagram. The only difference is that expansion in the proposed cycle occurs not adiabatically but as an isothermal process. The thermodynamic calculations have been carried out for 11 various fluids and 4 different cycles. The obtained results have clearly shown that cycles with isothermal expansion (isothermal turbines) are characterized by remarkably higher efffciency than typical power plants with adiabatic turbines. The increase in efffciency varies from 6 to 12 percent points for cycles with saturated live vapor and from 4 to 7 percent points for cycles with superheated live vapor. The performed analyses have shown that it is possible to achieve a very high efffciency (over 45%) of organic cycle, which is a very competitive value. In such cases the proposed power plants can achieve an efficiency which is higher than that of modern steam turbine plants with supercritical parameters.

  • SUBIEKTYWNA OCENA MULTIPLEKSU RADIOFONII LOKALNEJ DAB+ DZIAŁAJĄCEJ W GDAŃSKU I WROCŁAWIU
    • Przemysław Falkowski-Gilski
    • Stefan Brachmański
    • Andrzej Dobrucki
    2020 Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    Standard DAB+ (Digital Audio Broadcasting plus) jest wiodącym systemem naziemnej radiofonii cyfrowej. W porównaniu do analogowej radiofonii FM wszystkie usługi, obejmujące tradycyjne programy radiowe oraz usługi transmisji danych, grupowane są w zbiór (ensemble). Praca ta przedstawia proces rekonfiguracji polskiego multipleksu na przykładzie lokalnej radiofonii DAB+ w Gdańsku i Wrocławiu. Opisuje wyniki badań subiektywnych dotyczących jakości programów radiowych nadawanych jednocześnie w technice cyfrowej i analogowej.

  • Subjective and Objective Quality Evaluation Study of BPL -PLC Wired Medium
    • Grzegorz Debita
    • Przemysław Falkowski-Gilski
    • Marcin Habrych
    • Bogdan Miedziński
    • Bartosz Polnik
    • Jan Wandzio
    • Przemysław Jedlikowski
    2020 Full text Elektronika Ir Elektrotechnika

    This paper presents results of research on the effectiveness of bi-directional voice transmission in a 6 kV mine cable network using BPL-PLC (Broadband over Power Line - Power Line Communication) technology. It concerns both emergency cable state (supply outage with cable shorted at both ends) and loaded with distorted current waveforms. The narrowband (0.5 MHz–15 MHz) and broadband (two different modes, frequency range of 3 MHz–7.5 MHz) transmission efficiency, considered as an objective study, was correlated with the level of noise in the cable for both induction-inductive and mixed capacitive-inductive coupling of the measurement devices and/or modems. The quality of voice transmission, considered as a subjective study, was assessed by a group of 15 people aged between 25 and 35 years old. The test audio signals included samples in 3 languages sourced from ITU (International Telecommunication Union) and processed in 3 bitrates ranging from 8 kbps to 24 kbps.

  • Subjective Quality Evaluation of Speech Signals Transmitted via BPL-PLC Wired System
    • Przemysław Falkowski-Gilski
    • Grzegorz Debita
    • Marcin Habrych
    • Bogdan Miedziński
    • Przemysław Jedlikowski
    • Bartosz Polnik
    • Jan Wandzio
    • Xin Wang
    2020

    The broadband over power line – power line communication (BPL-PLC) cable is resistant to electricity stoppage and partial damage of phase conductors. It maintains continuity of transmission in case of an emergency. These features make it an ideal solution for delivering data, e.g. in an underground mine environment, especially clear and easily understandable voice messages. This paper describes a subjective quality evaluation of such a system. The solution was designed and tested in real-time operating conditions. It consists of a one-way transmission system, dedicated to delivering speech signals and voice commands. The study involved signal samples in three languages: English, German, and Polish, processed at different bitrates: 8, 16, and 24 kbps. Obtained results confirmed the usefulness of BPL-PLC technology for speech transmission purposes. Even in a narrowband scenario, with bitrates smaller than 1 Mbps, it proved to be a potentially life-saving communication system. Results of this study may aid researchers and parties from the mining and oil industry, as well as professionals involved in rescue operations.

  • Subjective Quality Evaluation of Underground BPL-PLC Voice Communication System
    • Grzegorz Debita
    • Przemysław Falkowski-Gilski
    • Marcin Habrych
    • Bogdan Miedziński
    • Bartosz Polnik
    • Jan Wandzio
    • Przemysław Jedlikowski
    2020

    Designing a reliable voice transmission system is not a trivial task. Wired media, thanks to their resistance to mechanical damage, seem an ideal solution. The BPL-PLC (Broadband over Power Line – Power Line Communication) cable is resilient to electricity stoppage and partial damage of phase conductors. It maintains continuity of transmission in case of an emergency situation, including paramedic rescue operations. These features make it an ideal solution for delivering data, e.g. in an underground mine environment. This paper describes a subjective quality evaluation of such a system. The solution was designed and tested in real-time operating conditions. It involved two types of coupling, namely: induction-inductive and capacitive-inductive, as well as two transmission modes (Mode 1 and Mode 11 operating in the 2–7.5 MHz frequency range). The tested one-way transmission system was designed to deliver clear and easily understandable voice messages. The study involved signal samples in three languages: English (both British and American dialects), German, and Polish, processed in three bitrates: 8, 16, and 24 kbit/s, with the Ogg Vorbis codec. Obtained results confirmed the usefulness of the BPL-PLC technology for voice communication purposes. Results of this study may be of interest to professionals from the mining and oil industry.