2020 - Repozytorium publikacji - Politechnika Gdańska

Pokaż publikacje z roku

Publikacje z roku 2020

Pokaż wszystkie

Electrochemical, theoretical and surface physicochemical studies of the alkaline copper corrosion inhibition by newly synthesized molecular complexes of benzenediamine and tetraamine with π acceptor
- Mohamed Ibrahim
- Gaber Mersal
- Ahmed Fallatah
- Murat Saracoglu
- Fatma Kandemirli
- Sarah Alharthi
- Sabine Szunerits
- Rabah Boukherroub
- Jacek Ryl
- Mohammed Amin
2020 JOURNAL OF MOLECULAR LIQUIDS
Two charge transfer complexes, namely [(BDAH)+(PA−)] CT1 [(BTAH)2+(PA−)2] and CT2 (BDAH = 1,2-benzenediamine, BTAH = 1,2,4,5-benzenetetramine, and PA− = 2,4,6-trinitrophenolate), were synthesized and fully characterized using various spectroscopic techniques. CT1 and CT2 were tested as inhibitors to effectively control the uniform and anodic corrosion processes of copper in an alkaline electrolyte (1.0 M KOH) using various electrochemical techniques. As a reference point, results were compared with the potassium salt of the π-acceptor potassium 2,4,6-trinitrophenolate (designated here as PA−K+). The highest inhibition efficiency (97%) was recorded for inhibitor CT2 at a concentration of 1.0 mM. The inhibition mechanism was discussed based on scanning electron microscopy and X-ray photoelectron spectroscopy results of the corroded and inhibited Cu surfaces. A theoretical study, based on quantum-chemical calculations of the synthesized compounds, performed by the DFT/B3LYP method with a 6-311++G(2d,2p) basis set by using Gaussian 09, Revision A.02 program, was also included to support experimental findings. The various quantum chemical parameters such as EHOMO, ELUMO, chemical hardness, and chemical softness of the investigated molecules were calculated, and their correlation with the inhibition efficiency of the synthesized compounds was discussed.
Electrochemically directed biofunctionalization of a lossy-mode resonance optical fiber sensor
- Monika Janik
- Paweł Niedziałkowski
- Katarzyna Lechowicz
- Marcin Koba
- Petr Sezemsky
- Vitezslav Stranak
- Tadeusz Ossowski
- Mateusz Śmietana
2020 Pełny tekst OPTICS EXPRESS
In this work, we present a direct electrochemical biofunctionalization of an indium-tin-oxide-coated lossy-mode resonance optical fiber sensor. The functionalization using a biotin derivative was performed by cyclic voltammetry in a 10 mM biotin hydrazide solution. All stages of the experiment were simultaneously verified with optical and electrochemical techniques. Performed measurements indicate the presence of a poly-biotin layer on the sensor’s surface. Furthermore, dual-domain detection of 0.01 and 0.1 mg/mL of avidin confirms the sensor’s viability for label-free detection.
Electro-chemo-mechanical properties in nanostructured Ca-doped ceria (CDC) by field assisted sintering
- Ahsanul Kabir
- Haiwu Zhang
- Sofie Colding-Jørgensen
- Simone Santucci
- Sebastian Molin
- Vincenzo Esposito
2020 Pełny tekst SCRIPTA MATERIALIA
Recent investigations have shown that highly oxygen defective cerium oxides generate non-classical electrostriction that is superior to lead-based ferroelectrics. In this work, we report the effect of field-assisted spark plasma sintering (SPS) on electro-chemo-mechanical properties of calcium doped ceria (CDC). Nanometric powders of Ca.10 nm are rapidly consolidated to form polycrystalline nanostructures with a high degree of crystalline disorder. Remarkably, the resultant material demonstrates a large electromechanical strain without a frequency-related relaxation effect. We conclude that electromechanical activity in CDC materials strictly depends on the Ca2+- interaction, while disorder at the crystalline boundaries has a minor effect.
Electrodeposited Biocoatings, Their Properties and Fabrication Technologies: A Review
- Andrzej Zieliński
- Michał Bartmański
2020 Pełny tekst Coatings
Coatings deposited under an electric field are applied for the surface modification of biomaterials. This review is aimed to characterize the state-of-art in this area with an emphasis on the advantages and disadvantages of used methods, process determinants, and properties of coatings. Over 170 articles, published mainly during the last ten years, were chosen, and reviewed as the most representative. The most recent developments of metallic, ceramic, polymer, and composite electrodeposited coatings are described focusing on their microstructure and properties. The direct cathodic electrodeposition, pulse cathodic deposition, electrophoretic deposition, plasma electrochemical oxidation in electrolytes rich in phosphates andcalciumions, electro-spark, andelectro-dischargemethods are characterized. The effects of electrolyte composition, potential and current, pH, and temperature are discussed. The review demonstrates that the most popular are direct and pulse cathodic electrodeposition and electrophoretic deposition. The research is mainly aimed to introduce new coatings rather than to investigate the effects of process parameters on the properties of deposits. So far tests aim to enhance bioactivity, mechanical strength and adhesion, antibacterial efficiency, and to a lesser extent the corrosion resistance.
Electrodes criticality: the impact of CRMs in the leachate electrochemical oxidation
- Mattia Pierpaoli
- Michał Rycewicz
- Aneta Łuczkiewicz
- Sylwia Fudala-Książek
- Robert Bogdanowicz
- Maria Letizia Ruello
2020 Pełny tekst Manufacturing Review
. Landfill leachate possesses high concentrations of ammonia, micropollutants, and heavy metals, and are characterised for low biodegradability. For this reason, conventional treatment technologies may result ineffective for complete pollutant removal. Electrochemical oxidation allows most of the of recalcitrant pollutants to be oxidised effectively within an easy operational and acceptable retention time, without the need to provide additional chemicals, and without producing waste materials. The mineralisation efficiency and electrode durability depend on the nature of the electrode material. The conventionally adopted anodes can contain critical raw materials (CRMs), and are subject to extreme corrosion conditions. CRM-free electrodes, such as carbon and graphite-based, exhibit a lower efficiency, and are subject to faster deactivation, or, as for lead-dioxide-based electrodes, can constitute a hazard due to the release into the effluent of the coating corrosion products. In this study, the relationship between electrode type, CRM content, and the removal efficiencies of organic compounds and ammonium-nitrogen (N-NH4) was investigated. Material criticality was estimated by the supply risk with economic importance indexes reported in the 2017 EU CRM List. The COD and N-NH4 removal efficiencies were obtained from a literature analysis of 25 publications. The results show that, while single and multi-oxide-coated electrodes may contain low amounts of CRM, but with limited efficiency, borondoped diamonds (BDD) may constitute the best compromise in terms of a reduced content of CRM and a high mineralisation efficiency.
Electromagnetic Modeling of Microstrip Elements Aided with Artificial Neural Network
- Łukasz Sorokosz
- Włodzimierz Zieniutycz
2020 Pełny tekst
The electromagnetic modeling principle aided withartificial neural network to designing the microwave widebandelements/networks prepared in microstrip technology is proposedin the paper. It is assumed that the complete information is knownfor the prototype design which is prepared on certain substratewith certain thickness and electric permittivity. The longitudinaland transversal dimensions of new design are calculated sep-arately using the scale coefficients which are determined fromtransmission line equation. Next the artificial neural networkcan be used for final tuning which should take into accountthe dispersion of microstrip line. The verification of proposedprocedure is shown for exemplary planar UWB balun.
Electromagnetic Simulation with 3D FEM for Design Automation in 5G Era
- Łukasz Balewski
- Michał Baranowski
- Maciej Jasiński
- Adam Lamęcki
- Michał Mrozowski
2020 ZTE COMMUNICATIONS
Electromagnetic simulation and electronic design automation (EDA) play an important role in the design of 5G antennas and radio chips. The simulation challenges include electromagnetic effects and long simulation time and this paper focuses on simulation software based on finite-element method (FEM). The state-of-the-art EDA software using novel computational techniques based on FEM can not only accelerate numerical analysis, but also enable optimization, sensitivity analysis and interactive design tuning based on rigorous electromagnetic model of a device. Several new techniques that help to mitigate the most challenging issues related to FEM based simulation are highlighted. In particular, methods for fast frequency sweep, mesh morphing and surrogate models for efficient optimization and manual design tuning are briefly described, and their efficiency is illustrated on examples involving a 5G multiple-input multiple-output (MIMO) antenna and filter. It is demonstrated that these new computational techniques enable significant reduction of time needed for design closure with the acceleration rates as large as tens or even over one hundred.
Electronic structure calculations in electrolyte solutions: Methods for neutralization of extended charged interfaces
- Arihant Bhandari
- Lucian Anton
- Jacek Dziedzic
- Chao Peng
- Denis Kramer
- Chris-Kriton Skylaris
2020 Pełny tekst JOURNAL OF CHEMICAL PHYSICS
Density functional theory (DFT) is often used for simulating extended materials such as infinite crystals or surfaces, under periodic boundary conditions (PBCs). In such calculations, when the simulation cell has non-zero charge, electrical neutrality has to be imposed, and this is often done via a uniform background charge of opposite sign (“jellium”). This artificial neutralization does not occur in reality, where a different mechanism is followed as in the example of a charged electrode in electrolyte solution, where the surrounding electrolyte screens the local charge at the interface. The neutralizing effect of the surrounding electrolyte can be incorporated within a hybrid quantum–continuum model based on a modified Poisson–Boltzmann equation, where the concentrations of electrolyte ions are modified to achieve electroneutrality. Among the infinite possible ways of modifying the electrolyte charge, we propose here a physically optimal solution, which minimizes the deviation of concentrations of electrolyte ions from those in open boundary conditions (OBCs). This principle of correspondence of PBCs with OBCs leads to the correct concentration profiles of electrolyte ions, and electroneutrality within the simulation cell and in the bulk electrolyte is maintained simultaneously, as observed in experiments. This approach, which we call the Neutralization by Electrolyte Concentration Shift (NECS), is implemented in our electrolyte model in the Order-N Electronic Total Energy Package (ONETEP) linear-scaling DFT code, which makes use of a bespoke highly parallel Poisson–Boltzmann solver, DL_MG. We further propose another neutralization scheme (“accessible jellium”), which is a simplification of NECS. We demonstrate and compare the different neutralization schemes on several examples.
Electron-impact ionization cross section calculations for 5-chloropyridine and 5-bromopyridine molecules
- Bożena Żywicka
- Paweł Możejko
2020 Pełny tekst Journal of Physics : Conference Series
The total cross sections for the single electron-impact ionization of 5-chloropyridine (5-C5H4ClN) and 5-bromopyridine (5-C5H4BrN) molecules have been calculated using binary-encounter-Bethe method for electron energies ranging from the ionization threshold up to 5 keV.
Electron-impact ionization cross section calculations for selected ribonucleosides
- Paweł Możejko
2020 Pełny tekst Journal of Physics : Conference Series
Total cross sections for the single electron-impact ionization of selected ribonuclosides (guanosine, adenosine, cytidine and uridine) have been calculated for electron energies ranging from the ionization threshold up to 5 keV.
Electrophoretic Deposition and Characteristics of Chitosan–Nanosilver Composite Coatings on a Nanotubular TiO2 Layer
- Michał Bartmański
- Łukasz Pawłowski
- Andrzej Zieliński
- Aleksandra Mielewczyk-Gryń
- Gabriel Strugała
- Bartłomiej Cieślik
2020 Pełny tekst Coatings
The surface treatment of titanium implants has been applied mainly to increase surface bioactivity and, more recently, to introduce antibacterial properties. To this end, composite coatings have been investigated, particularly those based on hydroxyapatite. The present research was aimed at the development of another coating type, chitosan–nanosilver, deposited on a Ti13Zr13Nb alloy. The research comprised characterization of the coating’s microstructure and morphology, timedependent nanosilver dissolution in simulated body fluid, and investigation of the nanomechanical properties of surface coatings composed of chitosan and nanosilver, with or without a surface-active substance, deposited at different voltages for 1 min on a nanotubular TiO2 layer. The microstructure, morphology, topography, and phase composition were examined, and the silver dissolution rate in simulated body fluid, nanoscale mechanical properties, and water contact angle were measured. The voltage value significantly influenced surface roughness. All specimens possessed high biocompatibility. The highest and best adhesion of the coatings was observed in the absence of a surface-active substance. Silver dissolution caused the appearanc
Electrophoretic Deposition and Characterization of Chitosan/Eudragit E 100 Coatings on Titanium Substrate
- Łukasz Pawłowski
- Michał Bartmański
- Gabriel Strugała
- Aleksandra Mielewczyk-Gryń
- Magdalena Jażdżewska
- Andrzej Zieliński
2020 Pełny tekst Coatings
Currently, a significant problem is the production of coatings for titanium implants, which will be characterized by mechanical properties comparable to those of a human bone, high corrosion resistance, and low degradation rate in the body fluids. This paper aims to describe the properties of novel chitosan/Eudragit E 100 (chit/EE100) coatings deposited on titanium grade 2 substrate by the electrophoretic technique (EPD). The deposition was carried out for different parameters like the content of EE100, time of deposition, and applied voltage. The microstructure, surface roughness, chemical and phase composition, wettability, mechanical and electrochemical properties, and degradation rate at different pH were examined in comparison to chitosan coating without the addition of Eudragit E 100. The applied deposition parameters significantly influenced the morphology of the coatings. The chit/EE100 coating with the highest homogeneity was obtained for Eudragit content of 0.25 g, at 10 V, and for 1 min. Young’s modulus of this sample (24.77 ± 5.50 GPa) was most comparable to that of human cortical bone. The introduction of Eudragit E 100 into chitosan coatings significantly reduced their degradation rate in artificial saliva at neutral pH while maintaining high sensitivity to pH changes. The chit/EE100 coatings showed a slightly lower corrosion resistance compared to the chitosan coating, however, significantly exceeding the substrate corrosion resistance. All prepared coatings were characterized by hydrophilicity.
Elektryczne zespoły zasobnikowe jako alternatywa dla elektryfikacji nowych linii w Trójmieście = Electric Multiple Units With Energy Storage – Alternative to Electrification of New Lines in Three City
- Dariusz Karkosiński
- Dominika Macedońska
- Natalia Karkosińska-Brzozowska
2020 Automatyka Elektryka Zakłócenia
Rozważono zastosowanie nowoczesnych zespołów trakcyjnych na liniach pasażerskich Trójmiasta. Zaproponowano budowę linii Gdańsk Śródmieście - Orunia Górna oraz odtworzenie komunikacji do północnych dzielnic Gdyni. Przeanalizowano trójmiejski układ komunikacyjny dla ruchu pociągów z zasobnikami energii. Zaproponowano trasę Orunia Górna - Wrzeszcz - Osowa - Chylonia - Port Oksywie z naprzemiennie występującymi odcinkami zelektryfikowanymi i niezelektryfikowanymi Wykonano wstępne obliczenia.
Elementy uczenia maszynowego na zajęciach matematyki
- Agnieszka Bartłomiejczyk
- Dawid Ptach
- Marcin Wata
2020 Pełny tekst Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
W artykule omówiono związki między matematyką kursową a wybranymi zagadnieniami związanymi z uczeniem maszynowym. Pokazano w jaki sposób proste operacje na macierzach pomagają serwisom VOD w rekomendacji tytułów filmowych zgodnych z zainteresowaniami użytkowników na podstawie ich wcześniejszych wyborów. Zaprezentowano również uproszczoną wersję algorytmu regresji wielorakiej stosowaną do wyceny nieruchomości oraz wspomniano o zastosowaniu sieci neuronowych w problemach klasyfikacyjnych.
Ella4Life virtual assistant - user centered design strategy - evaluation following labolatory tests
- Mariusz Kaczmarek
- Adam Bujnowski
- Kamil Osiński
- Edith Birrer
- Tomasz Neumann
- Barry Teunissen
2020
In the paper, we summarize the evaluation of Anne4Care system after laboratory tests. A group of end users, seniors over 55 years of age, rated a virtual assistant by completing a questionnaire. The objectives of the pilot evaluations are mainly to assess the feasibility, usability, acceptance and functionality of the system and the ability of the potential target user to use the system and receive valuable information from it to help them address the complex needs of elderly people. The results of the assessment will be taken into account during further product development.
Emission profile of butan-2-one oxime from commercially available neutral silicone sealant
- Krzysztof Klewicz
- Mariusz Marć
- Bożena Zabiegała
2020 Pełny tekst MICROCHEMICAL JOURNAL
The paper presents results of research on emission profile of butan-2-one oxime (methyl ethyl ketoxime, MEKO) released from two types of commercially available neutral silicone sealants: silicone type ‘S’ and silicone type ‘T’. To determine the emissions from silicone samples, the system consists of a stationary emission chamber, and the thermal desorption-gas chromatography-mass spectrometry system was applied. First, the research aimed to describe the emission profile of butan-2-one oxime considering different methods of application of silicone caulk: separate strips, merged strips, and dotted. Silicone sealant was applied in these three different ways to produce varying surfaces. As a result, significant differences in the emission profile were observed for the different methods of silicone application. The greatest difference in the emission rate was found to be between those of the dot shape and those of the separate strips; the emission rate was approximately five times smaller for dot shape. Moreover, the studies focused on quantitative emissions of butan-2-one oxime over a set time period. The research results indicate that, in the emission process of butan-2-oxime from a neutral silicone sealant, there are three main stages of emission. The first stage is dynamic emission, occurring during the first few days after application. The second stage is declining emission, and the third stage is stable residual emission. Between the first and third stages, the amounts of emitted oxime differ significantly. The difference in the emissions of butan-2-one oxime between the first and last stages of emission ranged from factors of 100 to 1000.
Emissions of selected monoaromatic hydrocarbons as a factor affecting the removal of single-use polymer barbecue and kitchen utensils from everyday use
- Mariusz Marć
2020 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT
The main focus of this study is the emission of monoaromatic hydrocarbons because these are the preliminary factors of potential solvent and monomer residues present in single-use plastic barbecue and kitchen utensils comprising polystyrene, polypropylene, natural cellulose, and biodegradable polymers intended for use with hot meal or beverages. Herein, the emissions of monoaromatic hydrocarbons (styrene, benzene, toluene, ethylbenzene, and xylene compounds and the total volatile organic compounds (TVOC)) fromnine types of disposable plastic utensils are reported. Seventy two samples of single-use plastic utensilswere conditioned at 40 and 80 °C using a stationary emission microchamber system. The average TVOC released from the studied polystyrene, polypropylene, and natural or biodegradable utensils were (2.3 ± 1.3), (1.01 ± 0.15), and (0.48 ± 0.37) μg g−1, respectively, at 40 °C and (11.1±1.2), (46.1±9.5), and (5.5±1.1) μg g−1, respectively, at 80 °C. Significant emissions of styrene (ranged from 3.5 up to 15.3 × 103 ng∙g−1), toluene (from 2.8 up to 0.53 × 103 ng∙g−1), and ethylbenzene (from3.7 up to 5.7 × 103 ng∙g−1) fromthe studied sampleswere observed, especially at 80 °C. Thus, elevated temperatures increase the potential emission of solvent and monomer residues fromplastics and could affect the quality of consumed meals or beverages, such as taste. Additionally, to determine the possible interactions between the measured chemical compounds in the plastic utensils, the Pearson's correlation coefficients were calculated.
Employee Commitment Matters for CSR Practice, Reputation and Corporate Brand Performance—European Model
- Wioleta Kucharska
2020 Pełny tekst Sustainability
So far, there have been no studies that explore how employee brand commitment moderates CSR practice outcomes. Employee brand commitment is often claimed as a focal input and output of the CSR. So, it means that it shapes CSR conditions. Then, it is a moderator. This study aims to verify it. Besides, commitment exists in many forms and can be achieved in many ways. Hence the question, if employees are committed to the brand, then how does it affect the outcomes of social responsibility practices such as corporate reputation or brand performance? This study analyzed a sample of 282 cases from the construction industry in Europe, using SPSS Amos and the PROCESS macro, to reveal the strong alignment of an excellent level of all three: CSR practice, corporate brand reputation, employee brand commitment. Still, it also shows that the high level of CSR practice may leverage corporate brand reputation even though employees are not brand committed. It exposes how meaningful the excellent level of CSR practice is. Moreover, the study also reveals that the lack of employee brand commitment may jeopardize reputation. So, the simplest way to achieve sustainability of brand performance is to keep employee brand commitment and CSR practice at the highest possible level to secure corporate brand reputation, which is a strong mediator between CSR practice and brand performance. The people are the company. So, in light of the study findings, it is clear that the future of corporate brands is in employees’ hands. Thus, companies should focus on improving employee commitment to achieve better corporate socialresponsibility practice outcomes. Moreover, the findings in this study present evidence supporting the importance of internal branding. This is the first study that has explored how employee brand commitment moderates CSR outcomes in a national context.
Employing Subjective Tests and Deep Learning for Discovering the Relationship between Personality Types and Preferred Music Genres
- Aleksandra Dorochowicz
- Adam Kurowski
- Bożena Kostek
2020 Pełny tekst Electronics
The purpose of this research is two-fold: (a) to explore the relationship between the listeners’ personality trait, i.e., extraverts and introverts and their preferred music genres, and (b) to predict the personality trait of potential listeners on the basis of a musical excerpt by employing several classification algorithms. We assume that this may help match songs according to the listener’s personality in social music networks. First, an Internet survey was built, in which the respondents identify themselves as extraverts or introverts according to the given definitions. Their task was to listen to music excerpts that belong to several music genres and choose the ones they like. Next, music samples were parameterized. Two parametrization schemes were employed for that purpose, i.e., low-level MIRtoolbox parameters (MIRTbx) and variational autoencoder neural network-based, which automatically extract parameters of musical excerpts. The prediction of a personality type was performed employing four baseline algorithms, i.e., support vector machine (SVM), k-nearest neighbors (k-NN), random forest (RF), and naïve Bayes (NB). The best results were obtained by the SVM classifier. The results of these analyses led to the conclusion that musical excerpt features derived from the autoencoder were, in general, more likely to carry useful information associated with the personality of the listeners than the low-level parameters derived from the signal analysis. We also found that training of the autoencoders on sets of musical pieces which contain genres other than ones employed in the subjective tests did not affect the accuracy of the classifiers predicting the personalities of the survey participants.
ENERGY ANALYSIS OF THE PROPULSION SHAFT FATIGUE PROCESS IN A ROTATING MECHANICAL SYSTEM PART II IDENTIFICATION STUDIES – DEVELOPING THE FATIGUE DURABILITY MODEL OF A DRIVE SHAFT
- Zbigniew Korczewski
- Konrad Marszałkowski
2020 Pełny tekst Polish Maritime Research
The article presents a continuation of research carried out concerning identification of energy consequences of mechanical fatigue within a propeller shaft in a rotating mechanical system, while working under conditions of the loss of the required alignment of shaft lines. Experimental research was carried out on a physical model reflecting a full-sized real object: i.e., the propulsion system of the ship. It is proven, by means of an active experiment, that changes in propeller shaft deflection are reflected in the amount of dissipated kinetic energy of masses in rotational motion and the accumulated internal energy in its construction material. Adoption of a high-cycle fatigue syndrome, consisting of diagnostic symptoms determined from the action of the propeller shaft associated with the transformation of mechanical energy into work and heat, as well as with the generation of mechanical vibrations and elastic waves of acoustic emission, is proposed. To assess the diagnostic information quantity brought about by the defined features of propeller shaft fatigue, an experimental research program was developed and implemented, in which two statistical hypotheses are verified: the significance of the impact of the values enforcing the fatigue process, presented in the first part of the article, and the adequacy of the regression equation describing the fatigue durability of the propeller shaft in the energy aspect, constituting the second part of the article. This finally gives us the opportunity, after the appropriate translation of the model test results into full-sized real objects, to develop a methodology to diagnose marine propeller shaft fatigue in operating conditions. The third part of the article is devoted to this issue