2024 - Publications Repository - Gdańsk University of Technology

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Publications from the year 2024

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Reception centres for refugees in polish urban space – specific challenges and design criteria
- Aleksandra Karpińska
- Robert Idem
2024 Środowisko Mieszkaniowe
The temporary accommodation of migrants is a contemporary challenge for those responsible for shaping the housing environment. As a result of the escalation of the refugee crisis, especially after the outbreak of war in Ukraine in 2022, we observe an increasing demand for the organization of shelters on a massive scale for people affected by the humanitarian crisis. This leads to the identification of requirements related to the adaptation of buildings in the urban space of Polish cities into reception centres for refugees. These requirements are based on the experience of already existing centres, as well as international and local standards in this field. Developing a comprehensive set of design and spatial criteria for refugee reception centres in Poland seems important given the urgent need to develop a long-term strategy for responding to the migration crisis. It also requires urban infrastructure planning to be considered through the lens of resilience, sustainability and inclusivity.
Receptor for advanced glycation end‐products: Biological significance and imaging applications
- Iwona T. Dobrucki
- Angelo Miskalis
- Michael B. Nelappana
- Catherine C. Applegate
- Marcin Woźniak
- Andrzej Czerwinski
- Leszek Kalinowski
- Lawrence W. Dobrucki
2024 Full text Wiley Interdisciplinary Reviews-Nanomedicine and Nanobiotechnology
The receptor for advanced glycation end-products (RAGE or AGER) is a transmembrane, immunoglobulin-like receptor that, due to its multiple isoform structures, binds to a diverse range of endo- and exogenous ligands. RAGE activation caused by the ligand binding initiates a cascade of complex pathways associated with producing free radicals, such as reactive nitric oxide and oxygen species, cell proliferation, and immunoinflammatory processes. The involvement of RAGE in the pathogenesis of disorders such as diabetes, inflammation, tumor progression, and endothelial dysfunction is dictated by the accumulation of advanced glycation end-products (AGEs) at pathologic states leading to sustained RAGE upregulation. The involvement of RAGE and its ligands in numerous pathologies and diseases makes RAGE an interesting target for therapy focused on the modulation of both RAGE expression or acti-vation and the production or exogenous administration of AGEs. Despite the known role that the RAGE/AGE axis plays in multiple disease states, there remains an urgent need to develop noninvasive, molecular imaging approaches that can accurately quantify RAGE levels in vivo that will aid in the validation of RAGE and its ligands as biomarkers and therapeutic targets. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Diagnostic Tools > Biosensing
Reconfigurable Antennas for Trustable Things
- Mateusz Groth
- Mateusz Rzymowski
- Krzysztof Nyka
- Łukasz Kulas
2024
In modern applications, the Internet of Things plays a significant role in increasing the productivity, effectiveness or safety and security of people and assets. Additionally, the reliability of Internet of Things components is crucial from the application point of view, where a resilient and low-latency network is needed. This can be achieved by utilizing reconfigurable antennas to enhance the capabilities of the wireless sensor network (WSN). Additionally, reconfigurable antennas can provide extended functionalities to the Internet of Things. One such aspect of wireless sensing is localization, where objects can be identified and positioned using radio frequency (RF) signals. For this purpose, analysis of spatial diversification of signals can be used by utilizing reconfigurable antennas. This work presents a design of a reconfigurable antenna that is applicable to Internet of Things WSNs and algorithms that utilize the antenna to provide additional localization functionalities
Recycled rubber wastes-based polymer composites with flame retardancy and electrical conductivity: Rational design, modeling and optimization
- Paulina Wiśniewska
- Natalia Wójcik
- Paulina Kosmela
- Jacek Ryl
- Robert Bogdanowicz
- Henri Vahabi
- Alireza Shadman
- Krzysztof Formela
- Mohammad Saeb
2024 COMPOSITES SCIENCE AND TECHNOLOGY
Polymer recycling techniques experience a maturity period of design and application. Rubbers comprise a high proportion of polymer wastes, highly flammable and impossible to re-melt. Polymer composites based on ground tire rubber (GTR) and ethylene-vinyl acetate copolymer (EVA) containing carbon black (CB) (1–50 phr), with variable EVA/GTR weight composition (10/90, 25/75, 50/50, 75/25 and 90/10), and processing temperature (Low: 100 °C and High: 200 °C) were designed applying Design of Experiments (DOE) approach of Optimal Design. The properties and performance features were experimentally evaluated. The tensile strength (TS) and elongation at break (EB) were optimized using Desirability Function (DF) approach. A wide fluidity window (Labeled POOR, GOOD, and EXCELLENT) and mechanical properties were observed. Overall, higher values of EB were assigned to samples processed at 200 °C. Cubic regression modeling and DF optimization of TS and EB indicated unlikely that one expect a TS ≥ 3 MPa, while EB values more than 500% were likely regardless of CB content for EVA-rich composites. The electrical properties of CB/EVA/GTR samples were examined by impedance spectroscopy technique. An interesting relationship was observed between the DC conductivity and the EVA/GTR ratio and processing temperature. GTR-rich samples showed much higher conductivity than EVA-dominated samples, attributed to the presence of CB in the rubber waste, which, together with the added CB, was able to create conduction paths for the transported electrons. Higher processing temperature of 200 °C improved dispersion of the added CB, i.e. a more even distribution of the conductive phase in the matrix. The uniform and evenly dispersed domains of particles were detected by SEM images for highly CB loaded composites. Surprisingly, 50/50 EVA/GTR composites were resilient against flame, while thermally stable ones in TGA measurements were highly CB loaded ones.
Recycling of Industrial Waste as Soil Binding Additives—Effects on Soil Mechanical and Hydraulic Properties during Its Stabilisation before Road Construction
- Witold Waciński
- Ksawery Kuligowski
- Małgorzata Olejarczyk
- Marek Zając
- Włodzimierz Urbaniak
- Waldemar Cyske
- Paweł Kazimierski
- Robert Tylingo
- Szymon Mania
- Adam Cenian
2024 Full text Materials
To improve the in situ soil stabilization, different chemical additives are used (ion exchange compounds, additives based on H2SO4 or vinyl polymers, and organic additives using lignosul- fonates). One interesting alternative is the production of additives from various waste materials. The extensive testing of waste-based blends with soil was performed; the mechanical (unconfined compressive strength (UCS)) and hydraulic (capillary rise, water absorption, and frost resistance (FR)) soil properties were measured. The optimization process led to obtaining additive compositions ensuring high strength and sealing properties: by-pass ash from the ceramics industry, waste H2SO4, pyrolytic waxes/oils from waste mixed plastics, waste tires and HDPE, and emulsion from chewing gum waste. For sandy soil, the following additives were the most promising: emulsion from pyrolytic wax (EPW) from waste PE foil (WPEF) with the addition of waste H2SO4, pyrolytic-oil emulsion from waste tires, EPW from waste mixed plastics with the addition of “by-pass” waste ash and NaOH, EPW from WPEF with the addition of NaOH, and EPW from WPEF reaching up to 93% FR, a 79.6% 7-day UCS increase, and a 27.6% of 28-day UCS increase. For clay: EPW from WPEF with the addition of NaOH, EPW from WPEF with the addition of waste H2SO4, and solely EPW from WPEF reaching up to 7.5% FR, an 80.7% 7-day UCS increase, and a 119.1% 28-day UCS increase.
REDUCING HOSPITAL-ACQUIRED INFECTIONS WITH THE USE OF ARCHITECTURAL MEASURES
- Rafał Janowicz
2024 Full text
Healthcare facilities are architectural objects designed under the strong influence of sanitary and hygienic requirements and guidelines of medical technology. During the process of planning future healthcare facilities and modernising already existing units, the need to provide safety to all their users comes as a significant aspect. In medical objects, it depends on the standard factors observed in public utility buildings. The proper architectural organisation of a medical facility, its design process and its implementation come as a way to minimise the possibility of epidemiological risk occurrence. Properly designed and implemented, a functional and spatial layout supported with advanced systems of technical installations, such as mechanical ventilation, tele-technical systems and efficient decontamination, can ensure effective functioning and sanitary and hygienic conditions that will be safe for all users.
Reducing income inequalities through government expenditures on education. Evidence for European countries Piotr PłatkowskiORCID Icon &Ewa LechmanORCID Icon
- Ewa Lechman
- Piotr Płatkowski
2024 APPLIED ECONOMICS LETTERS
This study examines the role of government spending on education in mitigating income inequalities. The study uses dynamic panel regressions to assess the evolution of education expenditures and income inequality in the sample of 30 European countries between 1995 and 2018. Our findings show that increases in government spending on education positively affect income inequality reduction. The impact was more substantial in case of less developed economies and countries with initially higher level of income inequalities, which stands for total expenditures on education, but also expenditures allocated to secondary and tertiary education.
Reducing the seismic failure potential of reinforced concrete frames
- Neda Asgarkhani
- Farzin Kazemi
- Ahmed Manguri
- Robert Jankowski
2024 Eurasian Journal of Science and Engineering
Nowadays, there is an extreme need for buildings with seismic resistance capability in rural areas, in which, it is possible to increase the floor number of buildings. In this study, the effects of number of bays and story levels on the seismic performance level of Reinforced Concrete (RC) frames were investigated. The 3-, 5-, 7-, and 9-story RC frames were modeled using ETABS software. In order to collapse state analysis, Incremental Dynamic Analyses (IDAs) were performed on the verified 2D models in Opensees subjected to near field records with and without pulse like (i.e., PL and NL) effects. The results of analysis showed that the number of bays had considerable effects on the seismic performance levels of RC frames and it should be considered in seismic design process. For this process, a specific procedure can be implemeted to connect the beams of lateral bays to the main moment-resisting frame. It should be noted that the beam connection should be further designed to resist axial and bending deformations of seismic load. In addition, it is recommended to use the result of this study for retrofitting purposes.
Reflective practice as a basis for building a sustainable public space: the case of Kartuzy
- Justyna Martyniuk-Pęczek
- Grzegorz Pęczek
2024 Urban Design International
Recent decades have been characterized by dynamic changes in the urban design process in post-transition countries such as Poland. Numerous activities have focused on upgrading the urban environment. The transformation that drives change also requires some new skills, which are described in the theory of reflective practice: observation, experience, and reflection. The goal of this paper is to build a descriptive scheme of the urban design process based on the reflective practice approach. The case of Kartuzy was chosen as the authors of this paper actively participated in this town’s 10-year redevelopment process, which can be seen as an experimental approach. The experience gathered allowed them to generate results on the issue of reflective practice, both in the sphere of practical skills and the theoretical results of research. One of the main conclusions is that knowledge exchange, observing the influence of actions of participants, and experiencing various types of interactions in the process of spatial development all drive reflection, which is a crucial element for taking another step in improving the quality of the urban design process. This paper contributes to a discussion on using reflective practice in the context of the development of public spaces towards making them more sustainable.
Regenarative tourism – between theory and practice
- Anna Dziadkiewicz
- Ewelina Sokołowska
- Justyna Borawska-Dziadkiewicz
2024 Full text Zeszyty Naukowe Politechniki Śląskiej. Seria Organizacja i Zarządzanie
Purpose: The aim of this article is to present a shift in thinking in terms of implementing the systems and practices needed to transition to a regenerative approach in tourism. The article aims to provide concrete ways to change thinking and move towards a regenerative paradigm in the tourism industry. Design/methodology/approach: This viewpoint paper defines regenerative tourism and explores its principles and the possibilities for driving transformational change in tourism. It outlines what a conscious approach to regenerative tourism entails and outlines working principles for regenerative tourism. The article concludes with a discussion of new regenerative thinking and practices. Findings: Transitioning towards regenerative tourism requires a change in systems, thinking and practice. Regenerative tourism requires a change in socio-ecological awareness in terms of both awareness of the financial benefits to the tourist destination, local society, and the owners of tourist facilities. Tourism must be managed as a complex adaptive system and overcome the challenges of polarisation, which is even more acute in times of economic, political, and social crises. Regenerative tourism requires a deeply committed bottom-up approach that is destination-based, community-centred and environmentally focused. Research limitations and implications: The article presents a point of view; it is not a typical research article. Nevertheless, it provides a rich field for future research in the implementation of of regenerative tourism activities. Practical and social implications: After indicating the scientific basis of regenerative tourism, the article provides recommendations and courses of action that can be used by tourism entrepreneurs. It can also be confidently used by entrepreneurs in other industries. Originality/value: This paper is based on both the literature on the subject and the reflections and recommendations of female researchers who share their long experience from different perspectives—economics, environment, and biotechnology—both academically and from business practice. As a result, the study identifies not only recommendations but also good practices that tourism entrepreneurs can apply to run their business in a regenerative way, while taking care of society, the economy, and the environment.
Rekurencyjny algorytm detekcji sygnału
- Bartosz Bossy
- Grzegorz Fotyga
- Aleksander Nowak
- Paweł Żykowski
2024 Full text Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne
W niniejszym artykule przedstawiono nowy rekurencyjny algorytm detekcji sygnału, bazując na analizie częstotliwościowo czasowej. Algorytm przetestowano dla szerokiej gamy rzeczywistych sygnałów zarejestrowanych z wykorzystaniem stanowiska pomiarowego. Wyniki pokazują, że zaproponowany algorytm bardzo dobrze wykrywa sygnał użyteczny, a w dodatku jest skalowany. Ponadto w obecnej postaci detekcja zajmuje dwukrotność czasu trwania sygnału, a możliwe jest zmniejszenie jej czasu poprzez m.in. zrównoleglenie obliczeń.
Relationship between GIX, SIDX, and ROTI ionospheric indices and GNSS precise positioning results under geomagnetic storms
- Grzegorz Nykiel
- Juan Andrés Cahuasquí
- Mohammed Mainul Hoque
- Norbert Jakowski
2024 Full text GPS SOLUTIONS
Ionospheric indices give information about ionospheric perturbations, which may cause absorption, diffraction, refraction, and scattering of radio signals, including those from global navigation satellite systems (GNSS). Therefore, there may be a relationship between index values and GNSS positioning results. A thorough understanding of ionospheric indices and their relationship to positioning results can help monitor and forecast the reliability and accuracy of GNSS positioning and support the precision and safety of life applications. In this study, we present the relationship between three indices: Gradient Ionosphere indeX (GIX), Sudden Ionospheric Disturbance indeX (SIDX), and Rate of Total electron content Index (ROTI) in relation to precise positioning results. We used two approaches: precise point positioning (PPP) and relative positioning for long baselines. We focus on GNSS stations located in Europe for two selected geomagnetic storms: March 17, 2015, and May 22, 2015. Our results show that in the case of PPP, positioning degradation occurred mainly at high latitudes and was mostly caused by rapid small-scale changes in ionospheric electron content represented by SIDX and ROTI. We also showed a significant correlation between cycle slips of GNSS signals and ROTI (0.88). The most significant degradations for relative positioning for low and medium latitudes were associated with large spatial gradients reflected by the GIX.
Relativistic Elastic Electron-Atom Scattering Near and At Zero Energy Threshold
- Michał Piłat
2024
The aim of this dissertation is to present the theory of relativistic electron-atom scattering at low energies. This work focuses on the theory of calculation of scattering length and how it can be formulated in the relativistic quantum theory. An approximate solution to the Dirac equation with polarization potential behaving as r-4 is presented as well as the formulation of the effective range theory for Dirac’s equation. Those formulas were later used to calculate the scattering lengths of argon, krypton, xenon, radon and oganesson. Values for argon, krypton and xenon coincide with the values obtained by different groups, both theoretically and experimentally. Values for radon and oganesson were obtained for the first time. In this work GRASP2018 computational package was used to calculate the bound states of an atom and the modified COWF code for obtaining the continuum states.
Removal of nitrogen from wastewater: Unsolved problems and possible solutions with partial denitrification/anammox systems
- Joanna Majtacz
- Hussein Al-Hazmi
- Xianbao Xu
- Grzegorz Piechota
- Xiang Li
- Gopalakrishnan Kumar
- Tejraj M. Aminabhavi
- Mohammad Saeb
- Michael Badawi
- Jacek Mąkinia
2024 CHEMICAL ENGINEERING JOURNAL
Abstract Nitrate (NO3−) is more stable than ammonia (NH4+) and nitrite (NO2−) among the majority of emerging pollutants in wastewater that can harm the ecosystem by depleting oxygen and water quality, thereby posing environmental and human health risks. Despite anaerobic ammonium oxidation (anammox) being a common method for nitrogen (N) removal from wastewater, it leaves behind residual NO3− of around 11 %. Maintaining the stability of N removal in the mainstream of wastewater (50–60 mg/L) is challenging due to the lack of intrinsic factors that suppress nitrite-oxidizing bacteria (NOB) and the accumulation of NO3−. Recently, partial denitrification/anammox (PD/A) has been recognized as a useful approach to eliminate NO3− and NH4+ from the sidestream (≥500 mg/L of N) and mainstream wastewater simultaneously. This review explores the complexities of sustaining stability in PD/A systems, including managing fluctuating NH4 + and NO3– levels while keeping a COD/N ratio of ≤ 3 to facilitate optimal NO2− production for the anammox. This review discusses the significance of temperature, pH, free ammonia, and free nitrous acid levels for optimal total N removal efficiency and PD/A stability in the long term. Strategies used for initiating and restoring the PD/A systems include optimized inoculum selection, granular sludge seeding, stepwise acclimation, bioaugmentation, unique substance incorporation, and innovative system design. Additionally, various strategies aim to enhance the stability by modifying the substance composition, introducing inorganic carbon and NO3−, incorporating heavy metals, embedding the biomass in gel carriers, adding microalgae, and adjusting hydraulic and solids retention time. These solutions aim to address the challenges to improve stability in the PD/A process. Future research roadmaps and supporting portfolios should address advancements and emerging technologies tackling the ongoing challenges in PD/A systems. These developments emphasize the significance of wastewater treatment for sustainable water availability to support the United Nations Sustainable Development Goal 6 (UN SDG 6) established in 2015.
Removal of phenolic inhibitor compounds from hydrolysates and post-fermentation broths by using a Hydrophobic Magnetic Deep Eutectic Solvent
- Zhila Honarmandrad
- Karolina Kucharska
- Massoud Kaykhaii
- Jacek Gębicki
2024 Journal of Environmental Chemical Engineering
Hydroxymethylfurfural (HMF), furfural (FF), hydroquinone (HQ), and vanillin (VAN) are among the main inhibitors generated during most of biomass pre-treatments prior to fermentation processes. They are recognized as toxic to several fermentative microorganisms and therefore cause a decrease in biohydrogen or biofuel production (after hydrolysis). Moreover, if they are released into aqueous solutions (after fermentation), they can be detrimental to the ecosystem. In this research, a new method for removing these inhibitor compounds from the broth after hydrolysis and fermentation is proposed. A hydrophobic magnetic deep eutectic solvent (HMDES), based on menthol: nonanoic acid in a mole ratio of 2:1 was prepared and magnetized with Fe3O4 nanoparticles and applied for effective sorption and removal of these inhibitors from the broth after fermentation and for biomass hydrolysates. Parameters affecting sorption, such as pH, volume of the inhibitors, initial concentration of inhibitors, volume of HMDES, temperature, stirring speed, and contact time, were studied and optimized. Under optimum conditions, the removal efficiency for HQ, HMF, FF, and VAN was obtained as 92.97, 86.72, 82.86 and 95.12% for the model samples. In addition, the removal efficiency of real samples after hydrolysis and fermentation for HQ, HMF, FF and VAN were higher than 83.3, 71.42, 69.99 and 76.80%, respectively. The studies on HMDES regeneration revealed that the removal efficiency remained constant even after undergoing 13 cycles of regeneration. The mechanism of inhibitor removal suggests that hydrogen bonding or van der Waals interactions may serve as the predominant factor influencing the extraction process.
Removal of selected sulfonamides and sulfonamide resistance genes from wastewater in full-scale constructed wetlands
- Ewa Felis
- Adam Sochacki
- Sylwia Bajkacz
- Aneta Łuczkiewicz
- Krzysztof Józwiakowski
- Joan García
- Jan Vymazal
2024 SCIENCE OF THE TOTAL ENVIRONMENT
Sulfonamides are high-consumption antibiotics that reach the aquatic environment. The threat related to their presence in wastewater and the environment is not only associated with their antibacterial properties, but also with risk of the spread of drug resistance in bacteria. Therefore, the aim of this work was to evaluate the occurrence of eight commonly used sulfonamides, sulfonamide resistance genes (sul1–3) and integrase genes intI1–3 in five full-scale constructed wetlands (CWs) differing in design (including hybrid systems) and in the source of wastewater (agricultural drainage, domestic sewage/surface runoff, and animal runs runoff in a zoo). The CWs were located in low-urbanized areas in Poland and in Czechia. No sulfonamides were detected in the CW treating agricultural tile drainage water. In the other four systems, four sulfonamide compounds were detected. Sulfamethoxazole exhibited the highest concentration in those four CWs and its highest was 12,603.23 ± 1000.66 ng/L in a CW treating a mixture of domestic sewage and surface runoff. Despite the high removal efficiencies of sulfamethoxazole in the tested CWs (86 %–99 %), it was still detected in the treated wastewater. The sul1 genes occurred in all samples of raw and treated wastewater and their abundance did not change significantly after the treatment process and it was, predominantly, at the level 105 gene copies numbers/mL. Noteworthy, sul2 genes were only found in the influents, and sul3 were not detected. The sulfonamides can be removed in CWs, but their elimination is not complete. However, hybrid CWs treating sewage were superior in decreasing the relative abundance of genes and the concentration of SMX. CWs may play a role in the dissemination of sulfonamide resistance genes of the sul1 type and other determinants of drug resistance, such as the intI1 gene, in the environment, however, the magnitude of this phenomenon is a matter of further research.
Renewable energy transition in Europe in the context of renewable energy transition processes in the world. A review
- Bartłomiej Igliński
- Urszula Kiełkowska
- Krzysztof Mazurek
- Sebsstian Drużyński
- Michał Pietrzak
- Gopalakrishnan Kumar
- Ashokkumar Veeramuthu
- Mateusz Skrzatek
- Marek Zinecker
- Grzegorz Piechota
2024 Full text Heliyon
Both the global and European energy sectors have been undergoing a deep transition for several years, associated with a reduction in the overall share of conventional coal-based energy in favor of new technologies, especially energy from renewable sources (RES). This transition is moving from centralized production towards distributed technologies and from providing only energy to end users towards combining innovative products and services with it. Electricity consumers are becoming prosumers connected to the grid and generating an increasing amount of energy. The original goal of decision-makers was to stop global warming and improve air quality. After Russia’s aggression of Ukraine in 2022, the EU transition efforts accelerated, and concerns about the climate were joined by issues related to energy security. After the painful experiences of the last several months, Europe wants to become independent from energy raw materials and their unstable suppliers as soon as possible, securing markets against price fluctuations, blackmail and unfair practices of some sellers. The aim of the article is to describe the current situation of energy and heat production from RES in selected countries in the aspect of contemporary energy transition (ET) processes. The achievement of the goal made it possible to present the European RES market in 2022, discuss the actions taken by European countries towards decarbonization and propose recommendations for the further development of the renewable energy market. The ET in Europe has been going on for over a dozen years, although there are countries, such as Norway, that use almost 100 % of renewable energy, as well as those that still largely use conventional fuels, such as Poland. In European countries, the energy mix of renewable energy, energy storage and green hydrogen should be developed. Green hydrogen produced in the electrolysis process from surplus renewable energy is an energy carrier with versatile applications both in the energy sector and in European industry.
Reply to Comment on ‘Nanodiamond incorporated human liver mimicking phantoms: prospective calibration medium of magnetic resonance imaging’
- Paweł Wierzba
- Anna Sękowska-Namiotko
- Agnieszka Sabisz
- Monika Kosowska
- Lina Jing
- Robert Bogdanowicz
- Małgorzata Szczerska
2024 Full text MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE
Dependence of the spin–lattice (T1) relaxation times on the nanodiamond concentration in human liver phantoms is discussed. Factors affecting stability and and reproducibility of these phantoms are presented. The need for comparative measurements on multiple MRI scanners for better understanding of potential variations in the obtained imaging data is emphasised.
Research of chitosan coatings deposited by electrophoretic deposition method at various voltage and time parameters
- Klaudia Malisz
- Beata Świeczko-Żurek
- Olive Jean-marc
- Gilles Pecastaings
- Alina Sionkowska
- Aleksandra Laska
- Grzegorz Gajowiec
2024 MATERIALS CHEMISTRY AND PHYSICS
The aim of this research is to estimate the electrophoretic deposition main parameters, such as voltage and time duration, that will provide optimal characteristics of the surface layer. Chitosan coatings were synthesized on biomedical Ti13Zr13Nb alloys at 20 V and 30 V and with deposit times of 2min, 5 min, 10 min, and 15 min. Evaluation of the coating was performed by using Scanning Electron Microscope (SEM), Energy-Dispersive Spectroscopy (EDS), Laser-Induced Breakdown Spectroscopy (LIBS), Atomic Force Microscopy (AFM), drop shape analyzer and nanoscratch tester. Homogeneous and continuous coatings are obtained for 2 min and 5 min, regardless of the voltage. Defects in form of bubbles are observed only for 20 V during 10 min, 20 V during 15 min, and 30 V during 10 min. All of the coatings show hydrophilic behavior. The critical loads for delamination range are between 100 mN and 300 mN. It is concluded, that the optimal coating for orthopedic implants is obtained at 20 V, 5 min, because of homogeneity, a contact angle supporting osseointegration and the best adhesion. The optimal one for implant in contact with blood is obtained at 20 V, 2 min, because it is homogenous and shows the lowest hydrophilicity, which should limit the thrombogenicity of the coating.
Research on the Flicker Effect in Modern Light Sources Powered by an Electrical Network
- Romuald Masnicki
- Janusz Mindykowski
- Beata Palczynska
- Dawid Werner
2024 ENERGIES
Disruptions in power quality have a negative impact on many energy consumers. These include lighting, where interference manifests itself, among others, in the form of light flickering. The article presents phenomena accompanying the operation of modern light sources against the background of exemplary results of studies on the flicker of conventional light sources, such as incandescent or fluorescent lamps. The flickering effect of light generated in modern lamps can occur under stable voltage conditions in the supply network. The main subjects of the conducted research were solid-state light sources—light-emitting diode (LED) lamps, currently available on the lighting market. To assess the effects of these phenomena, it is necessary to use measures other than those traditionally used. The method used allows for the measurement of flicker resulting from both power supply disturbances and the properties of modern light sources. Using the developed measurement system, it is possible to record temporal changes in flicker coefficients resulting from, for example, changing supply voltage conditions. Due to the possibility of flickering light from sources offered by different manufacturers, as shown by research, it is advisable to carry out measurements at the place of use of the lighting.