2021 - Publications Repository - Gdańsk University of Technology

Show publications from the year

Publications from the year 2021

Show all

Highly Miniaturized Self-Diplexed U-Shaped Slot Antenna Based on Shielded QMSIW
- Rusan Barik
- Sławomir Kozieł
- Qingsha Cheng
- Stanisław Szczepański
2021 Full text IEEE Access
This article presents an efficient yet simple design approach to highly miniaturized cavity-backed self-diplexing antenna (SDA) with high-isolation. The structure employs a shielded quarter-mode substrate integrated waveguide (QMSIW). Two U-shaped slots are engraved on the top conducting plane, which realize two frequency bands and significant size reduction. The slots are excited by two independent 50Ω orthogonal feed-lines to achieve high isolation while enabling radiation at 3.5 GHz and 5.4 GHz. The proposed design approach allows us to design the two frequency bands independently from each other. The SDA structure is verified using an equivalent circuit model, full-wave electromagnetic (EM) analysis, and experimental validation of the antenna prototype. Excellent consistency between simulated and measured responses has been demonstrated. According to the measurement, the SDA has peak gains of 5.26/5.60 dBi at 3.5/5.4 GHz, and the return loss better than 21.6 dB. The isolation between ports is greater than 40 dB, whereas excellent front-to-back-ratio and co-to-cross polarization are obtained for the proposed SDA. Furthermore, the total size of the SDA is only 0.129 λ2, with λ being the guided wavelength at 3.5 GHz.
Highly Oriented Zirconium Nitride and Oxynitride Coatings Deposited via High‐Power Impulse Magnetron Sputtering: Crystal‐Facet‐Driven Corrosion Behavior in Domestic Wastewater
- Anna Dettlaff
- Mateusz Brodowski
- Marcin Kowalski
- Vitezslav Stranak
- Vadym Prysiazhnyi
- Ewa Klugmann-Radziemska
- Jacek Ryl
- Robert Bogdanowicz
2021 Full text ADVANCED ENGINEERING MATERIALS
Herein, highly crystalline ZrxNy and ZrxNyOz coatings are achieved by the deposition via high‐power impulse magnetron sputtering. Various N2 and N2/O2 gas mixtures with argon are investigated. The chemical composition and, as a result, mechanical properties of the deposited layer can be tailored along with morphological and crystallographic structural changes. The corrosion resistance behavior is studied by potentiodynamic measurements and electrochemical impedance spectroscopy in a sample of synthetic wastewater designed to imitate real‐life domestic wastewater. The corrosion current density of the ZrxNyOz coating is in the range of 33–70 μA cm−2, whereas for the zirconium nitride layers, values below 1.0 μA cm−2 are achieved. The highest corrosion resistance of 64 nm year−1 is observed for the ZrxNy coating deposited with 1.00% N2 content in the gas mixture with a corrosion potential of −0.41 V Ag/AgCl.
Highly selective impedimetric determination of Haemophilus influenzae protein D using maze-like boron-doped carbon nanowall electrodes
- Mateusz Brodowski
- Marcin Kowalski
- Marta Skwarecka
- Katarzyna Pałka
- Michał Skowicki
- Anna Kula
- Tomasz Lipiński
- Anna Dettlaff
- Mateusz Ficek
- Jacek Ryl
- Karolina Dziąbowska
- Dawid Nidzworski
- Robert Bogdanowicz
2021 Full text TALANTA.The International Journal of Pure and Applied Analytical Chemistry
This study reports a novel impedimetric immunosensor for protein D detection in purified and bacterial (Haemophilus influenzae, Hi) samples. The detection was based on antigen recognition by anti-protein D antibodies (apD) immobilised at the maze-like boron-doped carbon nanowall electrodes (B:CNW). The B:CNW electrodes were synthesised, and their surface was characterised by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) methods. The sensor was prepared in a two-step procedure: apD were covalently linked on the previously modified B:CNW electrodes using diazonium salt. Modification steps were controlled by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) measurements. The immunosensor exhibited excellent electrochemical performance, stability, satisfactory sensitivities, and linear ranges for antigen detection. Protein D was detected down to 2.39×102 fg/mL with a linear range extending from 3.37×10-11 to 3.37×10-3 μg/mL (in purified sample). Next, Hi’s LOD was 5.20×102 CFU/mL with a linear range of 8.39×101–8.39×103 CFU/mL. Selectivity studies showed no reaction with negative samples as Streptococcus pyogenes, Streptococcus pneumoniae or Bordetella parapertussis bacteria. Therefore, the new approach is suitable for rapid and quantitative detection of Hi, and is a good candidate for further tests on clinical samples.
High-performance NdSrCo2O5+δ–Ce0.8Gd0.2O2-δ composite cathodes for electrolyte-supported microtubular solid oxide fuel cells
- Sea-Fue Wang
- Yung-Fu Hsu
- Yi-Le Liao
- Shih-Ting Huang
- Piotr Jasiński
2021 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
NdSrCo2O5+δ (NSCO) is a perovskite with an electrical conductivity of 1551.3 S cm−1 at 500 °C and 921.7 S cm−1 at 800 °C and has a metal-like temperature dependence. This perovskite is used as the cathode material for Ce0.8Gd0.2O2-δ (GDC)-supported microtubular solid oxide fuel cells (MT-SOFCs). The MT-SOFCs fabricated in this study consist of a bilayer anode, comprising a NiO–GDC composite layer and a NiO layer, and a NSCO–GDC composite cathode. Three cell designs with different outer tube diameters, GDC thicknesses, and NSCO/GDC ratios are designed. The MT-SOFC with an outer tube diameter of 1.86 mm, an electrolyte thickness of 180 μm, and a 5NSCO–5GDC composite cathode presents the best performance. The flexural strength of the aforementioned cell is 177 MPa, which is sufficient to confer mechanical integrity to the cell. Moreover, the ohmic and polarization resistance values of the cell are 0.22 and 0.09 Ω cm2 at 700 °C, respectively, and 0.15 and 0.03 Ω cm2 at 800 °C, respectively. These results indicate that the NSCO-GDC composite exhibits high electrochemical activity. The maximum power densities of the cell at 700 and 800 °C are 0.46 and 0.67 W cm−2, respectively, exceeding those of existing electrolyte-supported MT-SOFCs with similar electrolyte thicknesses.
High-Power Jamming Attack Mitigation Techniques in Spectrally-Spatially Flexible Optical Networks
- Giannis Savva
- Konstantinos Manousakis
- Jacek Rak
- Ioannis Tomkos
- Georgios Ellinas
2021 Full text IEEE Access
This work presents efficient connection provisioning techniques mitigating high-power jamming attacks in spectrally-spatially flexible optical networks (SS-FONs) utilizing multicore fibers. High-power jamming attacks are modeled based on their impact on the lightpaths’ quality of transmission (QoT) through inter-core crosstalk. Based on a desired threshold on a lightpath’s QoT, the modulation format used, the length of the path, as well as a set of physical layer characteristics, each lightpath can potentially tolerate a high-power jamming attack. In this paper, an integer linear program is thus formulated, as well as heuristic algorithms to solve the problem of attack-aware routing, spectrum, modulation format, and core allocation in SS-FONs, aiming to both efficiently provision the network in terms of network resources, as well as minimize the impact of high-power jamming attacks on the established lightpaths. Extensive simulation results are obtained for several algorithm variants with different objectives, demonstrating the validity and efficiency of the proposed techniques that can effectively mitigate high-power jamming attacks, by minimizing the number of inter-core interactions, while at the same time establishing connections with high spectral efficiency.
Ho2Pd1.3Ge2.7 – a ternary AlB2-type cluster glass system
- Leszek Litzbarski
- Tomasz Klimczuk
- Michał Winiarski
2021 Full text RSC Advances
We report a successful synthesis of a ternary AlB2-type intermetallic compound. The phase purity was obtained by fine-tuning the Pd-Ge ratio out of the idealized 1-3. Attempts to synthesize an Er analogue were not successful. We discuss the instability of the Er analogue based on the atomic size ratio and also suggest that the increased stability of Ho2Pd1+xGe3−x in the Pd-rich range likely stems from a combination of atomic size ratio, electronic, and entropic factors. The new Ho2Pd1.3Ge2.7 compound is found to exhibit cluster glass behavior with a freezing temperature of T ≈ 2.3 K.
Hold-Up Problems in International Gas Trade: A Case Study
- Guych Nuryyev
- Tomasz Korol
- Ilia Tetin
2021 Full text ENERGIES
The infrastructure required for international natural gas trade is considerable, which often leads to hold-up problems and supply disruptions. This study discusses disruptions of gas supply from Algeria, Indonesia, Russia, and Turkmenistan since the early 1980s. The novelty of this study is its focus on the issues related to transit countries, which are rarely considered in the literature. The results of the study classify supply disruptions into six types, show the evolution of supply disruptions over time, and discuss mitigation strategies. The six types of disruptions include political change, price demands, debts, technical issues, transit fees, theft of gas. The evolution of the disruptions shows that the issues related to transit countries have become more frequent in the last two decades. Mitigation strategies tailored to transit countries include using an international organisation, designing contracts with price mechanisms that might reduce the possibility of disputes and reducing the number of parties involved in the trade
Homoclinics for singular strong force Lagrangian systems in R^N
- Marek Izydorek
- Joanna Janczewska
- Nils Waterstraat
2021 Full text CALCULUS OF VARIATIONS AND PARTIAL DIFFERENTIAL EQUATIONS
We will be concerned with the existence of homoclinics for second order Hamiltonian systems in R^N (N>2) given by Hamiltonians of the form H(t,q,p)=Φ(p)+V(t,q), where Φ is a G-function in the sense of Trudinger, V is C^2-smooth, periodic in the time variable, has a single well of infinite depth at a point ξ and a unique strict global maximum 0 at the origin. Under a strong force type condition aroud the singular point ξ, we prove the existence of a homoclinic solution, avoiding the singularity, via minimization of an action integral defined in an appropriate Orlicz-Sobolev space. We find a candidate for a solution as weak limit of a minimizing sequence and show directly that it is a critical point of the action functional. Our results extend those by Tanaka in [28].
Honey antibacterial activity: A neglected aspect of honey quality assurance as functional food
- Juraj Majtan
- Marcela Bucekova
- Ioannis Kafantaris
- Piotr Szweda
- Katherine Hammer
- Dimitris Mossialos
2021 TRENDS IN FOOD SCIENCE & TECHNOLOGY
Background Honey is considered as a functional food with health-promoting properties. Its potent antibacterial and antibiofilm effects are the major attributes of so called ‘medical-grade honey’ which is topically used for the treatment of burns, wounds and skin disorders. Nevertheless, the current set of honey quality parameters adopted in the European Union do not include its biological properties. Furthermore, in light of the accelerated growth of scientific evidence, there is an urgent need to revise current qualitative tools, and to establish and certify more effective honey quality control. Scope and approach This up-to-date narrative review aims to discuss the recent clinical evidence describing the use of honey in the management of various disorders including respiratory tract infections, metabolic and gastro-intestinal derangements. Current knowledge about the antibacterial activity of honey, as the most studied biological properties of natural honey, focusing on mechanism of action and the factors/compounds responsible for the antibacterial effects is also discussed. In addition, the weaknesses of current honey quality parameters are highlighted and a new potentially qualitative parameter that takes into account honey functionality is presented. Key findings and conclusions Data from in vitro and in vivo experiments, as well as human clinical studies clearly indicate the importance and efficacy of honey as an antibacterial agent. Antibacterial activity can vary from honey to honey but must not be identical to the activity of the honey sugar content. In most cases, antibacterial activity can be negatively impacted by thermal processing and long-term storage and this activity is therefore a suitable and sensitive quality parameter. From a clinical point of view, we strongly advocate to solely use natural honey that has undergone only minimal processing in order to preserve the full spectrum of biological activities.
How Chain Transfer Leads to a Uniform Polymer Particle Morphology and Prevents Reactor Fouling
- Lidia Jasińska-Walc
- Rob Duchateau
- Miloud Bouyahyi
- Joey Aarts
- Amin Syed
- Erik Delsman
2021 Full text MACROMOLECULES
ABSTRACT: The effect of adding diethyl zinc as a chain transfer agent during the polymerization of propylene in heptane performed at 80 °C was studied. Although it was expected that the chain transfer would stop after precipitation of the polymer, the polymer molecular weight continued to increase throughout the whole of the polymerization. The presence of diethyl zinc had an additional effect that the polymerizations were devoid of reactor fouling. To unravel this phenomenon, the polymer particle morphology was studied. Under the conditions applied, surprisingly, uniform platelet-shaped polymer particles were formed. At high polymer content, these particles aggregate into microfibrillar structures consisting of nematic columnar strands of the same uniform platelets. The polymer particle morphology, as a result of controlled crystallization, is believed to play a crucial role in preventing reactor fouling.
How Do Ionic Liquids Affect the Surface Structure of Titania Photocatalyst? An Electron-Trap Distribution-Analysis Study
- Justyna Łuczak
- Anna Pancielejko
- Guangyi Chen
- Mai Takashima
- Adriana Zaleska-Medynska
- Bunsho Ohtani
2021 Full text Journal of Physical Chemistry C
Titanium(IV) oxide, titania, photocatalyst particles were prepared from titanium alkoxide in the presence of several kinds of ionic liquids, and it was clarified that a group of samples exhibited photocatalytic activity for phenol degradation under the irradiation of light of wavelength >400 nm higher than those of the other group of samples. Although the conventional structural analytical results could not be related to the activity, electron-trap distribution measured by reversed double-beam photoacoustic spectroscopy suggested that a part of the ionic liquid induced the creation of a surface amorphous layer covered with hydrophobic organic residues to enhance the adsorption of phenol on the surface.
How Machine Learning Contributes to Solve Acoustical Problems
- Marie A. Roch
- Peter Gerstoft
- Bożena Kostek
- Zoi-Heleni Michalopoulou
2021 Full text Journal of the Acoustical Society of America
Machine learning is the process of learning functional relationships between measured signals (called percepts in the artificial intelligence literature) and some output of interest. In some cases, we wish to learn very specific relationships from signals such as identifying the language of a speaker (e.g. Zissman, 1996) which has direct applications such as in call center routing or performing a music information retrieval task (Schedl et al., 2014). Alternatively, we may be interested in an exploratory analysis, such as discovering relationships between animal-produced sounds and potential call categories that may carry signaling information (e.g. Sainburg et al., 2020). Machine learning can be used to discover information about the physical world such as determining the distance to a source based on pressure levels in a vertical line array (Niu et al., 2017) or solving inversion problems to find geoacoustic parameters of a seabed (Benson et al., 2000). In this article, we provide a gentle, and hopefully intuitive introduction to machine learning with only a limited number of examples and techniques. For readers who wish to read a more detailed introduction, we recommend the recently published review by Bianco et al. (2019) that focuses on machine learning and acoustics, or one of the many excellent book-length treatments of machine learning (e.g. Bishop, 2006; Goodfellow et al., 2016; Hastie et al., 2009).
Human awareness versus Autonomous Vehicles view: comparison of reaction times during emergencies
- Aleksander Rydzewski
- Paweł Czarnul
2021
Human safety is one of the most critical factors when a new technology is introduced to the everyday use. It was no different in the case of Autonomous Vehicles (AV), designed to replace generally available Conventional Vehicles (CV) in the future. AV rules, from the start, focus on guaranteeing safety for passengers and other road users, and these assumptions usually work during normal traffic conditions. However, there is still a problem with proper reaction time to sudden, dangerous and unexpected scenarios like a running animal on a rural road during the night. In this paper, we compare human and AV responses to sudden scenarios and accidents. As the AV topic can be analyzed as an ICT system, we review modern sensors, computer architectures and algorithms designed for this type of problems. Beside regular analysis, we also show which algorithms can run simultaneously and if vehicles have proper tools to guarantee safety during regular system delays. As a final result, we present a diagram which depicts Autonomous Vehicle logic and allows to identify bottlenecks. Additionally, the analysis shows how different refresh rates and algorithm execution times can affect the braking distance thus safety of other road users.
Human Centric Lighting w miejscach pracy
- Natalia Sokół
2021 Full text Architektura-Murator
Wyniki badań wskazują na poszerzenie zakresu efektów odziaływania światła dziennego na człowieka od komfortu pracy wzrokowej po jakość snu, czujność, nastrój, wydajność i stan zdrowia [1]. Ta złożoność wiąże się z nakładami finansowymi ponoszonymi przez społeczeństwo na badania, ale również na tworzenie optymalnego środowiska oświetleniowego w miejscach pracy. HCL to termin, który wywołuje wiele dyskusji w branży oświetleniowej. Jest to koncept projektowania we wnętrzach dynamicznego oświetlenia elektrycznego, które symuluje to naturalne, a zwłaszcza jego zmienność, jeśli chodzi o temperaturę barwową, poziomy natężenia oraz czas ekspozycji. W literaturze HCL opisuje się jako ideę oświetlenia skutecznego biologicznie (bioefektywnego) czy biologicznie spersonalizowanego. Zgodnie z wynikami najnowszych badań naukowych, które wskazują, że oświetlenie elektryczne we wnętrzach powinno dynamicznie i synergicznie zmieniać się w zależności od charakterystyki wpadającego do nich
Hybrid energy storage forelectric multiple units to operate at the partially electrified line Gdynia -Hel
- Dariusz Karkosiński
- Paweł Stromski
- Natalia Karkosińska-Brzozowska
2021 Full text Pojazdy Szynowe
The article presents calculations enabling the selection of an on-board energy storage device to replace diesel-powered trains with modern storage multiple units on the example railway line Gdynia Główna -Hel. The pioneering and currently used storage electric multiple units, mainly in Europe, were presented. The condensed results of the inventory of the line in question, including the technical condition of the stations of the non-electrified line 213 Reda -Hel, are included. Moreover, an analysis of the terrain pos-sibilities of building new passing loops aimed at increasing the capacity of line 213 is presented. The cal-culations of the theoretical passage and energy demand of the storage train unit on the non-electrified part of the analyzed route are presented. The results of the calculations were used to select the on-board energy storage consisting of batteries and supercapacitors.
Hybrid metal and non-metal activation of Oxone by magnetite nanostructures co-immobilized with nano-carbon black to degrade tetracycline: Fenton and electrochemical enhancement with bio-assay
- Reza Darvishi
- Masumeh Naderi
- Grzegorz Boczkaj
- Sahand Jorfi
- Alireza Khataee
2021 SEPARATION AND PURIFICATION TECHNOLOGY
Electrochemically synthesized magnetite nanostructures (ESMNPs) as a metal activator and nano-carbon black (NCB) as a non-metal activator were co-immobilized by alginate natural polymer to activate Oxone for the degradation of tetracycline (TC) antibiotic. The formation of sulfate radical was indirectly confirmed during the Oxone/ESMNPs/NCB/alginate process via the addition of scavenging compounds. This study revealed the high reusability potential of the ESMNPs/NCB/alginate with a negligible decrease in the degradation rate from 5.7 × 10−2 to 4.9 × 10−2 min−1 after four experimental runs. The release of iron ions into the effluent did not violate its discharge standard, indicating high stability of the catalyst due to the co-immobilization. The enhanced degradation rate of 6.7 × 10−2 min−1 was observed under basic conditions. Both Fenton (7.9 × 10−2 min−1) and electrochemical (7.7 × 10−2 min−1) processes improved the degradation effectiveness at hydrogen peroxide concentration of 30 mM and current density of 100 mA, respectively. Response surface methodological optimization of the bio-assessment was also performed. Accordingly, the optimized TC concentration of 68 mg/L, Oxone concentration of 1.6 mM and exposure time of 60 min resulted in the minimum inhibition percent (%) of 15.8%. Confirmatory real experiments demonstrated the results of numerical optimization. Possible degradation pathways along with the ECOSAR-based bioassay of the intermediates were also proposed.
Hydration of Simple Model Peptides in Aqueous Osmolyte Solutions
- Aneta Panuszko
- Maciej Pieloszczyk
- Anna Kuffel
- Karol Jacek
- Karol Biernacki
- Sebastian Demkowicz
- Janusz Stangret
- Piotr Bruździak
2021 Full text INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
The biology and chemistry of proteins and peptides are inextricably linked with water as the solvent. The reason for the high stability of some proteins or uncontrolled aggregation of others may be hidden in the properties of their hydration water. In this study, we investigated the effect of stabilizing osmolyte–TMAO (trimethylamine N-oxide) and destabilizing osmolyte–urea on hydration shells of two short peptides, NAGMA (N-acetyl-glycine-methylamide) and diglycine, by means of FTIR spectroscopy and molecular dynamics simulations. We isolated the spectroscopic share of water molecules that are simultaneously under the influence of peptide and osmolyte and determined the structural and energetic properties of these water molecules. Our experimental and computational results revealed that the changes in the structure of water around peptides, caused by the presence of stabilizing or destabilizing osmolyte, are significantly different for both NAGMA and diglycine. The main factor determining the influence of osmolytes on peptides is the structural-energetic similarity of their hydration spheres. We showed that the chosen peptides can serve as models for various fragments of the protein surface: NAGMA for the protein backbone and diglycine for the protein surface with polar side chains.
Hydrogen Bonds in Blends of Poly(N-isopropylacrylamide), Poly(N-ethylacrylamide) Homopolymers, and Carboxymethyl Cellulose
- Alberto García-Peñas
- Weijun Liang
- Saud Hashmi
- Gaurav Sharma
- Mohammad Saeb
- Florian J. Stadler
2021 Full text Journal of Composites Science
Recently, it was reported that the physical crosslinking exhibited by some biopolymers could provide multiple benefits to biomedical applications. In particular, grafting thermoresponsive polymers onto biopolymers may enhance the degradability or offer other features, as thermothickening behavior. Thus, different interactions will affect the different hydrogen bonds and interactions from the physical crosslinking of carboxymethyl cellulose, the lower critical solution temperatures (LCSTs), and the presence of the ions. This work focuses on the study of blends composed of poly(N-isopropylacrylamide), poly(N-ethylacrylamide), and carboxymethyl cellulose in water and water/methanol. The molecular features, thermoresponsive behavior, and gelation phenomena are deeply studied. The ratio defined by both homopolymers will alter the final properties and the gelation of the final structures, showing that the presence of the hydrophilic groups modifies the number and contributions of the diverse hydrogen bonds.
Hydrological responses to large-scale changes in land cover of river watershed: Review
- Hadi Muhammed
- Andam Mustafa
- Tomasz Kolerski
2021 Full text Journal of Water and Land Development
Despite many studies on the hydrological responses to forest cover changes in micro and mesoscale watersheds, the hydrological responses to forest cover alterations and associated mechanisms through the large spatial scale of the river watershed have not been comprehensively perceived. This paper thus reviews a wide range of available scientific evidence concerning the impacts exerted by the forest removal on precipitation, water yield, stream flow, and flow regimes. It is concluded that there is no statistical correlation between forest cover and precipitation and water yield at the micro and mesoscale. In contrast, there is a relative correlation coefficient (r = 0.77, p < 0.05) between forest cover and water yield at large scales (>1000 km2). These findings help our understanding of the hydrological response to forest disturbance at large and regional scale and provide a scientific perception to future watershed management in the context of human activities and natural hazards.
Hydrothermal Cobalt Doping of Titanium Dioxide Nanotubes towards Photoanode Activity Enhancement
- Mariusz Wtulich
- Mariusz Szkoda
- Grzegorz Gajowiec
- Maria Gazda
- Kacper Jurak
- Mirosław Sawczak
- Anna Lisowska-Oleksiak
2021 Full text Materials
Doping and modification of TiO2 nanotubes were carried out using the hydrothermal method. The introduction of small amounts of cobalt (0.1 at %) into the structure of anatase caused an increase in the absorption of light in the visible spectrum, changes in the position of the flat band potential, a decrease in the threshold potential of water oxidation in the dark, and a significant increase in the anode photocurrent. The material was characterized by the SEM, EDX, and XRD methods, Raman spectroscopy, XPS, and UV-Vis reflectance measurements. Electrochemical measurement was used along with a number of electrochemical methods: chronoamperometry, electrochemical impedance spectroscopy, cyclic voltammetry, and linear sweep voltammetry in dark conditions and under solar light illumination. Improved photoelectrocatalytic activity of cobalt-doped TiO2 nanotubes is achieved mainly due to its regular nanostructure and real surface area increase, as well as improved visible light absorption for an appropriate dopant concentration