2019 - Repozytorium publikacji - Politechnika Gdańska

Pokaż publikacje z roku

Publikacje z roku 2019

Pokaż wszystkie

Nikola Tesla i jego niezwykłe osiągnięcia
- Dariusz Świsulski
2019 Śląskie Wiadomości Elektryczne
W artykule przybliżono sylwetkę amerykańskiego wynalazcy serbskiego pochodzenia Nikoli Tesli. Omówiono jego studia i pracę, współpracę i konflikt z Edisonem oraz pierwsze patenty. Przedstawiono wybrane wynalazki i osiągnięcia tego niezwykłego inżyniera i wizjonera, którego celem było wykorzystanie wynalazków do poprawy ludzkiego życia. Jednym z największych osiągnięć Tesli było znalezienie praktycznego zastosowania dla prądu przemiennego.
Niskokosztowe mierniki pyłu PM10
- Bartosz Szulczyński
- Jacek Gębicki
2019
Ochrona środowiska to jedna z dziedzin, w których ocena jakości powietrza atmosferycznego ma istotne znaczenie. Jakość powietrza zarówno wewnętrznego, jak i zewnętrznego jest jednym z kluczowych czynników wpływających na zdrowie człowieka. Ocena jakości powietrza nie jest jednak zadaniem łatwym. Powietrze jest bowiem złożonym układem, podlegającym zmianom nawet w krótkim czasie Jedną z głównych przyczyn występowania przekroczeń dopuszczalnych poziomów stężeń i dopuszczalnych poziomów stężeń docelowych (PM10, ozon i benzo(a)piren) w aglomeracji trójmiejskiej jest występowanie niskiej emisji z indywidualnych systemów grzewczych oraz emisji liniowej z ciągów komunikacyjnych. Prowadzenie monitoringu jakości powietrza w ramach Państwowego Monitoringu Środowiska wymaga użycia odpowiedniej ilości urządzeń pomiarowych spełniających wymagania stawiane metodom odniesienia. Taka sytuacja wiąże się z ponoszonymi wysokimi nakładami finansowymi. Zastosowanie w prowadzeniu monitoringu jakości powietrza mierników opartych na niskokosztowych czujnikach optycznych wydaje się słuszną i obiecującą drogą. Wdrożenie tych urządzeń nie tylko spowoduje obniżenie kosztów prowadzenia monitoringu, ale również może zwiększyć gęstość punktów pomiarowych, co w konsekwencji zapewni uzyskanie bardziej miarodajnej informacji o jakości powietrza na danym terenie. W pracy przedstawiono wyniki badań terenowych przeprowadzonych na terenie Aglomeracji Trójmiejskiej w celu oceny przydatności niskokosztowych czujników PM10 w monitorowaniu jakości powietrza atmosferycznego. Wyniki zestawiono z wynikami uzyskanymi za pomocą metod referencyjnych. Ponadto oceniono wpływ czynników zewnętrznych (wilgotność, ciśnienie, temperatura) na uzyskane wyniki.
Nitrogen and phosphorus compounds in coastal aquifers in Puck municipality area (northern Poland)
- Dawid Potrykus
- Małgorzata Pruszkowska-Caceres
- Beata Jaworska-Szulc
- Wioletta Gorczewska-Langner
- Anna Gumuła-Kawęcka
- Adam Szymkiewicz
- Lidia Dzierzbicka-Głowacka
2019
1. Groundwater study shows local variations in chemical composition of selected aquifers caused by human impact The diversity is mainly manifested in • time variation of groundwater chemical composition of all analyzed parameters especially in shallow aquifers (Q1) • relationship between t he ground water chemical composition and depth of the aquifer where an inverse concentration distribution occurs higher concentrations are observed in shallow aquifers (Pa and Q1) • mosaic spatial distribution of the pollution indicators which means pollution has a local character caused by anthropogenic activity 2. Composition of the basic pollution indicators in groundwater shows local impact of agriculture as well as contamination from households and farms which can potentially influence the quality of water in Puck Bay via SGD This is a subject of ongoing research
Nitrogen dioxide gas-sensing detection with GO modified CuO thin films
- Aleksandra Szkudlarek
- Michał Kawa
- Grzegorz Jasiński
- Piotr Jasiński
- Artur Rydosz
2019
Gas sensors have been continuously developed over the last few decades for several applications including air quality monitoring, automotive industry and recently for medical use. Gas sensors are usually based on metal oxides (MOXs), such as SnO2, TiO2, ZnO, WO3, CuO. Recently, new materials such as graphene oxide and heterostructures of graphene oxide and metal oxides are utilized for gassensing applications.
Noise in electrical double-layer capacitors (EDLCs)
- Janusz Smulko
- Arkadiusz Szewczyk
- Łukasz Lentka
2019 Pełny tekst
We present methods and problems of noise measurements in electrical double-layer capacitors (EDLC). Detailed noise equivalent electronic circuit is considered, and two possible ways of observations of random processes generated in the EDLCs structures are studied. We conclude that noise is a useful tool for characterization of the EDLC structures and their state-of-health, as in other materials and electronic devices. Eventual, practical applications of noise measurements are proposed to determine the state-of-health of the EDLCs.
Non-conventional approach in single-sided lapping process: kinematic analysis and parameters optimization
- Adam Barylski
- Norbert Piotrowski
2019 Pełny tekst INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
The lapping process is strongly affected by a number of input parameters. One of the fundamental mechanical processes in lapping is the abrasive effect of particles. In order to examine the influence of the kinematic parameters on the lapping uniformity of unconventional single-sided machine, numerical simulations of particles sliding trajectories are performed. Changing the kinematic parameters, e.g., rotational velocities or position of the conditioning rings together with the workpieces can be used for correcting the profile of an active surface of the lap. This paper provides a basic guide to the kinematic parameter settings of single-sided lapping process. Furthermore, an unconventional single-sided lapping system, where a conditioning ring performs additional motion during the machining, is described. Simulation results show that the rotational speed ratio of the conditioning ring to the lapping plate k1 and the period ratio of the reciprocating motion to the lapping plate rotary motion k2 represent the relationships among the three basic motions of unconventional lapping systems and are major factors affecting trajectory distribution. Material removal rate and trajectory density parameter are proposed to optimize the kinematic parameters for better uniformity of lapping plate wear. The preferred kinematic parameter values for single-sided lapping system with reciprocating motions and the assumed size of the machine are k1=0,78 and k2=2. The general results were validated on a specially designed test stand.
Non-Destructive Testing of a Sport Tribune under Synchronized Crowd-Induced Excitation Using Vibration Analysis
- Karol Grębowski
- Magdalena Rucka
- Krzysztof Wilde
2019 Pełny tekst Materials
This paper presents the concept of repairing the stand of a motorbike speedway stadium. The synchronized dancing of fans cheering during a meeting brought the stand into excessive resonance. The main goal of this research was to propose a method for the structural tuning of stadium stands. Non-destructive testing by vibration methods was conducted on a selected stand segment, the structure of which recurred on the remaining stadium segments. Through experiments, we determined the vibration forms throughout the stand, taking into account the dynamic impact of fans. Numerical analyses were performed on the 3-D finite element method (FEM) stadium model to identify the dynamic jump load function. The results obtained on the basis of sensitivity tests using the finite element method allowed the tuning of the stadium structure to successfully meet the requirements of the serviceability limit state.
Non-enzymatic flexible glucose sensing platform based on nanostructured TiO2–Au composite
- Katarzyna Grochowska
- Jacek Ryl
- Jakub Karczewski
- Gerard Śliwiński
- Adam Cenian
- Katarzyna Siuzdak
2019 Pełny tekst JOURNAL OF ELECTROANALYTICAL CHEMISTRY
All over the world the number of people suffering from diabetes and related complications is drastically growing. Therefore, the need for accurate, reliable and stable sensor for monitoring of glucose in human body fluids is becoming highly desirable. In this work we show that material composed of gold layers deposited onto TiO2 nanotubes (NTs) formed onto the flexible Ti foil exhibits great response toward glucose oxidation and can be successfully used as electrodes in non-enzymatic and non-invasive electrochemical sensors. TiO2NTs have been prepared via anodization process followed by calcination at 450 °C in order to ensure formation of anatase crystalline phase. Next, gold layers (up to 100 nm) have been deposited on the NTs by means of the magnetron sputtering. The SEM imaging confirmed presence of the well-aligned nanotubes and preservation of their initial architecture after metal deposition for Au thicknesses up to 50 nm. Basing on electrochemical results in the presence of glucose in neutral and alkaline solutions, the optimal Au thickness was found to ensure both the best response and cost-effectiveness. The detection limit of 50 μM and sensitivity of 45 μA/cm2mM obtained under neutral conditions confirm that prepared material can be used for glucose detection at levels typical for blood, urine or saliva. Moreover, the proposed electrodes exhibit great tolerance to extensive exploitation and multiple bending.
Non-isolated resonant quasi-Z-source network DC–DC converter
- Marek Adamowicz
2019 Pełny tekst ELECTRONICS LETTERS
A novel non-isolated resonant quasi-impedance (quasi-Z)-source network DC–DC converter is proposed. The resonant impedance source network is derived from the quasi-Z-source network by including the autotransformer-based resonant cell instead of the second inductor of the quasi-Z-network. The leakage inductance of the autotransformer and two resonant capacitors connected in series with the autotransformer windings constitute a high-frequency resonant tank. At the same time, the resonant capacitors block the DC-bias current of the autotransformer. The resonant operation with a sinusoidal current of the main switch and diodes enables electromagnetic interference mitigation and improves the efficiency of the converter. Experimental results of a 100 W, 30 V/200 V prototype are presented to verify the analysis results of the proposed converter.
Non-Linear Analysis of Inter-Story Pounding between Wood-Framed Buildings during Ground Motion
- Wojciech Migda
- Marcin Szczepański
- Natalia Lasowicz
- Anna Jakubczyk-Gałczyńska
- Robert Jankowski
2019 Pełny tekst Geosciences
Pounding between adjacent buildings during ground motion may result in structural damage or lead to total destruction of structures. The research on the phenomenon has recently been much advanced; however, the analyses have been carried out only for concrete, steel, and masonry structures, while pounding between wooden buildings has not been studied so far. The aim of this paper is to show the results of detailed non-linear seismic analysis of inter-story pounding between the wood-framed buildings modelled by using the finite element method. Firstly, the modal analysis of the structures was conducted. Then, the detailed non-linear analysis of earthquake-induced collisions between two wood-framed buildings of different heights was carried out. The results of the analysis indicate that the behavior of both structures in the longitudinal as well as in the transverse direction is significantly influenced by interactions. The response of the taller building is increased in both directions. On the other hand, the response of the lower building is decreased in the longitudinal direction, while it is increased in the transverse one. The results of the study presented in the paper indicate that, due to deformability of buildings made of wood, structural interactions may change their responses much more, as compared to steel, reinforced concrete, or masonry structures.
Nonlinear Control of a Doubly Fed Generator Supplied by a Current Source Inverter
- Krzysztof Blecharz
- Marcin Morawiec
2019 Pełny tekst ENERGIES
Nowadays, wind turbines based on a doubly fed induction generator (DFIG) are a commonly used solution in the wind industry. The standard converter topology used in these systems is the voltage source inverter (VSI). The use of reverse-blocking insulated gate bipolar transistor (RB-IGBT) in the current source inverter topology (CSI), which is an alternative topology, opens new possibilities of control methods. This paper presents a novel power control system for a DFIG supplied by a CSI. The authors propose to use multi-scalar DFIG state variables. A nonlinear control method realized by feedback linearization was used to control the active and reactive powers of the generator. In the feedback linearization controls, the nonlinear DFIG model was taken into account. In the control system structure, classical proportional–integral controllers were used. The control variables were the output current vector components of the CSI. Such approach was named the “current control”. The proposed control method is characterized by good dynamic properties which, combined with the inverter properties in the rotor circuit, allow to increase the quality of the energy transferred to the grid by the generator. In the simulation tests, the correctness of the decoupling of the active and reactive power control loops, the dynamics of controlled power changes, and the change of the machine operating range resulting from the increase of the rotational speed of the generator shaft were controlled. The simulation studies also evaluated the impact of changes in the value of the passive elements of the system on the operation of the generator system. Characteristic operating states of the generator system were analyzed using computer simulations.
Nonlinear finite element modeling of vibration control of plane rod-type structural members with integrated piezoelectric patches
- Jacek Chróścielewski
- Rüdiger Schmidt
- Victor Eremeev
2019 Pełny tekst CONTINUUM MECHANICS AND THERMODYNAMICS
This paper addresses modeling and finite element analysis of the transient large-amplitude vibration response of thin rod-type structures (e.g., plane curved beams, arches, ring shells) and its control by integrated piezoelectric layers. A geometrically nonlinear finite beam element for the analysis of piezolaminated structures is developed that is based on the Bernoulli hypothesis and the assumptions of small strains and finite rotations of the normal. The finite element model can be applied to static, stability, and transient analysis of smart structures consisting of a master structure and integrated piezoelectric actuator layers or patches attached to the upper and lower surfaces. Two problems are studied extensively: (i) FE analyses of a clamped semicircular ring shell that has been used as a benchmark problem for linear vibration control in several recent papers are critically reviewed and extended to account for the effects of structural nonlinearity and (ii) a smart circular arch subjected to a hydrostatic pressure load is investigated statically and dynamically in order to study the shift of bifurcation and limit points, eigenfrequencies, and eigenvectors, as well as vibration control for loading conditions which may lead to dynamic loss of stability.
Nonlinear Interaction of Modes in a Planar Flow of a Gas with Viscous and Thermal Attenuation
- Anna Perelomova
2019 Pełny tekst Archives of Acoustics
The nonlinear interaction of wave and non-wave modes in a gas planar flow are considered. Attention is mainly paid to the case when one sound mode is dominant and excites the counter-propagating sound mode and the entropy mode. The modes are determined by links between perturbations of pressure, density, and fluid velocity. This definition follows from the linear conservation equations in the differential form and thermodynamic equations of state. The leading order system of coupling equations for interacting modes is derived. It consists of diffusion inhomogeneous equations. The main aim of this study is to identify the principle features of the interaction and to establish individual contributions of attenuation (mechanical and thermal attenuation) in the solution to the system
NON-LINEAR MASTIC CHARACTERISTICS BASED ON THE MODIFIED MSCR (MULTIPLE STRESS CREEP RECOVERY) TEST
- Grzegorz Mazurek
- Marek Pszczoła
- Cezary Szydłowski
2019 Pełny tekst Structure and Environment
Mastic containing asphalt in its composition is an example of a viscoelastic material. It is an effective binder in asphalt. It consists of a filler (<0.063 mm) and asphalt mixed in the right proportions. Just like in asphalt, its response depends on the temperature level, the load and stress time. Changing the stress stiffness of the mastic affects the non-linear course of the stress-strain relationship. Modelling of the non-linear course of the mastic response for any stress history was performed using a single-integral Schapery equation. Two mastic composites made using filler to asphalt 2:1 ratio, was used in the tests. In addition, the contents of the filler, in one of the compositions, was enriched with hydrated lime in an amount of 15% in relation to the mass of the lime filler. It was found that the use of non-linear viscoelasticity model describes, in a comprehensive manner, the change in strain over time with different stress histories. In addition, hydrated lime reduced strains in the mastic compared to a composition consisting of limestone dust only.
Nonlinear planar modeling of massive taut strings travelled by a force-driven point-mass
- Manuel Feretti
- Serge Gavrilov
- Victor Eremeev
- Angelo Luongo
2019 Pełny tekst NONLINEAR DYNAMICS
The planar response of horizontal massive taut strings, travelled by a heavy point-mass, either driven by an assigned force, or moving with an assigned law, is studied. A kinematically exact model is derived for the free boundary problem via a variational approach, accounting for the singularity in the slope of the deflected string. Reactive forces exchanged between the point-mass and the string are taken into account via Lagrange multipliers. The exact model is consistently simplified via asymptotic analysis, which leads to condense the horizontal displacement as a passive variable. The dynamic increment of tension, with respect the static one, is neglected in the governing equations, but evaluated a posteriori, as a higher-order quantity in a perturbation perspective. The equations are solved and rearranged in the form of an integral equation coupled with an integro-differential equation, thus extending a procedure already introduced in the literature. Numerical results, showing the importance of the horizontal reactive force on the quality of motion, are discussed, generalizing those relevant to massless strings.
Nośność stalowych słupów złożonych z kształtowników giętych na zimno o przekroju poprzecznym otwartym z dodatkowymi gałęziami przylgowymi.
- Patryk Deniziak
2019 Pełny tekst
W niniejszej pracy opisano zagadnienie wzajemnej współpracy gałęzi przylgowo złożonego słupa wykonanego z kształtowników wykonanych w technologii gięcia na zimno. Przedstawiono proces przygotowania eksperymentu laboratoryjnego wykonanego w skali naturalnej, przebieg badań oraz sposób wykonania modelu numerycznego w programie Abaqus. Wyniki analizy numerycznej porównano z wynikami eksperymentu. Na tej podstawie dokonano walidacji modelu numerycznego. Przeprowadzono także obliczenia parametryczne wykraczające poza zakres ograniczony eksperymentem. Pracę wieńczy rozdział, w którym przedstawiono wnioski i podsumowanie rezultatów pracy. Przedstawiono także kierunki dalszych badań.
Novel bio-based thermoplastic poly(ether-urethane)s. Correlations between the structure, processing and properties
- Paulina Kasprzyk
- Janusz Datta
2019 POLYMER
The main purpose of this work was to analyze the effect of the number of unreacted isocyanate groups and the [NCO]/[OH] molar ratio during the chain extension of a prepolymer during the polymerization process on the structure, processing and selected properties of thermoplastic poly(ether-urethane)s. Three series of novel thermoplastic polyurethanes were obtained via a prepolymer route. Three prepolymers were synthesized from diisocyanate and bio-based polyol, which contained 6, 7 and 8% of unreacted isocyanate groups. The prepolymer chains were extended by using bio-based 1,4-butanediol with four different [NCO]/[OH] molar ratios. It was confirmed that the concentration of unreacted isocyanate groups in the prepolymer has an effect on the degree of the hard segment phase separation of poly(ether-urethane)s. It was also found that the melt flow index has a significant impact on the processing of polyurethanes which can be correlated to the chemical structure and dynamic mechanical properties of the polyurethanes.
Novel Coplanar-Strip-Based Excitation Technique for Design of Broadband Circularly Polarization Antennas with Wide 3-dB Axial Ratio Beamwidth
- Ullah Ubaid
- Sławomir Kozieł
2019 IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
In this paper, a novel excitation technique for design of a single-point-fed compact low-profile wide-slot antennas with broadband circular polarization (CP) and wide 3 dB axial ratio (AR) beamwidth is presented. Two inverted L-shape parasitic strips placed coplanar to the microstrip line of an asymmetric CPW, and a horizontal strip that protrudes from the vertical edge of the backside ground plane of the substrate are used for CP excitation. The overall footprint of the structure is only Ls × Ws = 0.3 λ0 × 0.28 λ0 when measured at the lowest operating frequency. The antenna prototype has been validated experimentally. The measured results indicate that a wide impedance bandwidth of 72% (2.26 GHz-4.85 GHz) and a CP bandwidth of 66% (2.44 GHz- 4.87 GHz) can be achieved. In addition to the wideband characteristics in terms of the impedance bandwidth and CP, a stable bidirectional radiation pattern with a wide 3 dB beamwidth of 85° ± 5° is obtained for 58% of the total CP bandwidth without involving any complex circuitry. Furthermore, by placing a flat metallic reflector behind the antenna, a unidirectional radiation pattern is produced without changing the geometrical dimensions of the proposed antenna. The average realized gain of the antenna without a reflector is 3.3 dBi, whereas it increases up to 6.3 dBi with the substrate-size reflector.
Novel steroid sulfatase inhibitors based on N ‐thiophosphorylated 3‐(4‐aminophenyl)‐coumarin‐7‐O‐sulfamates
- Mateusz Daśko
- Sebastian Demkowicz
- Karol Biernacki
- Amira Harrous
- Janusz Rachoń
- Witold Kozak
- Aleksandra Martyna
- Maciej Masłyk
- Konrad Kubiński
- Anna Boguszewska‐Czubara
2019 Pełny tekst DRUG DEVELOPMENT RESEARCH
In the present work, we described convenient methods for the synthesis ofN-thiophosphorylated 3-(4-aminophenyl)-coumarin-7-O-sulfamates as steroid sulfatase(STS) inhibitors. To design the structures of the potential STS inhibitors, molecularmodeling techniques were used. A computational docking method was used to deter-mine the binding modes of the synthesized inhibitors as well as to identify potentialinteractions between specified functional groups on the inhibitors and the amino acidresidues present in the active site of the enzyme. The inhibitory activities of the syn-thesized compounds were tested in an enzymatic assay with STS isolated from ahuman placenta. Within the set of newly synthesized compounds,9edemonstratedthe highest inhibitory activity in the enzymatic assay with an IC50value of 0.201μM(the IC50value of667-COUMATEin the same test was 0.062μM). Furthermore, wetried to verify if the obtained STS inhibitors are able to pass through the cellular mem-brane effectively in cell line experiments. In the course of our study, we determinedthe STS activity in the MCF-7 cell line after incubation in the presence of the inhibitors(at 100 nM concentration). For this evaluation, we included newly synthesized com-pounds9a-gand theirN-phosphorylated analogs6a-h, whose synthesis has been pre-viously described. We found that the lowest STS activities were measured in thepresence ofN-phosphorylated derivatives6e(0.1% of STS activity) and6f(0.2% ofSTS activity). The measured STS activity in the presence of667-COUMATE(used as areference) was 0.1%. Moreover, at concentrations up to 1μM, the most active com-pounds (6e,6f,9b,and9e) did not exert any toxic effects on zebrafish embryos.
Novel therapeutic compound acridine–retrotuftsin action on biological forms of melanoma and neuroblastoma
- Miroslawa Cichorek
- Anna Ronowska
- Monika Gensicka-Kowalewska
- Milena Deptula
- Iwona Pelikant-Malecka
- Krystyna Dzierzbicka
2019 Pełny tekst JOURNAL OF CANCER RESEARCH AND CLINICAL ONCOLOGY
PURPOSE: As a continuation of our search for anticancer agents, we have synthesized a new acridine-retrotuftsin analog HClx9-[Arg(NO2)-Pro-Lys-Thr-OCH3]-1-nitroacridine (named ART) and have evaluated its activity against melanoma and neuroblastoma lines. Both tumors develop from cells (melanocytes, neurons) of neuroectodermal origin, and both are tumors with high heterogeneity and unsatisfactory susceptibility to chemotherapies. Thus, we analyzed the action of ART on pairs of biological forms of melanoma (amelanotic and melanotic) and neuroblastoma (dopaminergic and cholinergic) with regard to proliferation, mechanism of cell death, and effect on the activity of tricarboxylic acid cycle (TAC) enzymes. METHODS: The cytotoxicity of ART was evaluated by XTT and trypan blue tests. Cell death was estimated by plasma membrane structure changes (phosphatidylserine and calreticulin externalization), caspase activation, presence of ROS (reactive oxygen species), activity of tricarboxylic acid cycle enzymes (pyruvate dehydrogenase complex, aconitase, and isocitrate dehydrogenase), NAD level, and ATP level. RESULTS: ART influences the biological forms of melanoma and neuroblastoma in different ways. Amelanotic (Ab) melanoma (with the inhibited melanogenesis, higher malignancy) and SHSY5Y neuroblastoma (with cholinergic DC cells) were especially sensitive to ART action. The Ab melanoma cells died through apoptosis, while, with SH-SY5Y-DC neuroblastoma, the number of cells decreased but not as a result of apoptosis. With Ab melanoma and SH-SY5Y-DC cells, a diminished activity of TAC enzymes was noticed, along with ATP/NAD depletion. CONCLUSION: Our data show that the biological forms of certain tumors responded in different ways to the action of ART. As a combination of retrotuftsin and acridine, the compound can be an inducer of apoptotic cell death of melanoma, especially the amelanotic form. Although the mechanism of the interrelationships between energy metabolism and cell death is not fully understood, interference of ART with TAC enzymes could encourage the further investigation of its anticancer action.