2019 - Repozytorium publikacji - Politechnika Gdańska

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Influence of Fragment Size on the Time and Temperature of Ethylene Vinyl Acetate Lamination Decomposition in the Photovoltaic Module Recycling Process
- Anna Kuczyńska-Łażewska
- Ewa Klugmann-Radziemska
2019 Pełny tekst Materials
Photovoltaics is a commercially available and reliable technology with significant potential for long-term growth in nearly all global regions. Several research institutes and companies are working on recycling concepts for thin film modules and modules with crystalline cells. The establishment of recycling and reuse technologies appropriate and applicable to all photovoltaics (PV) modules is a key issue to be addressed as part of corporate social responsibility to safeguard the environment and to implement a fully material-circulated society without any waste. The copolymer ethylene-vinyl acetate (EVA) layer is a thermoplastic containing cross-linkable ethylene vinyl acetate, which is used to encapsulate the photovoltaic cells. The cells are laminated between films of EVA in a vacuum, under compression, and up to 150·°C. The encapsulant’s primary purpose is to bond or laminate the multiple layers of the module together. In the photovoltaic module recycling process, the second important step (after mechanical dismantling of the frame) is EVA lamination removal. In this study, different parameters of the thermal delamination method used during the recycling process were experimentally tested and compared, and the most ecological and economical one is proposed.
Influence of High Temperature Oxidation on Hydrogen Absorption and Degradation of Zircaloy-2 and Zr 700 Alloys
- Andrzej Zieliński
- Anita Cymann
- Adrian Gumiński
- Anna Hernik
- Grzegorz Gajowiec
2019 Pełny tekst HIGH TEMPERATURE MATERIALS AND PROCESSES
The present research was aimed at determining the effects of the oxide layers on hydrogen absorption, microstructure and mechanical properties of the Zircaloy- 2 and Zr 702 alloys. The oxidation was made at 350 °C, 700 °C and 900 °C for 10 to 30 min in laboratory air, followed by hydrogen cathodic charging for 72 h and annealing at 400 °C for 4 h. The slow strain rate tests were carried out on oxidized, charged and annealed specimens. The oxidation resulted in thick and cracked, more for Zr 702 alloy, layer. After oxidation at 350 °C, the appearance of hydrides in Zircaloy-2 and absence of hydrides in Zr 702 alloy were observed. After oxidation at high temperatures no current flow was noticed at applied voltage up to 5 V, and no hydrogen or hydrogen cracks. The observed effects were attributed to the phase structure of investigated alloys at low hydrogen content.
INFLUENCE OF INLET GEOMETRY ON THE EFFICIENCY OF 1MW STEAM TURBINE
- Arkadiusz Koprowski
- Dominik Gotowski
- Romuald Rządkowski
- Ryszard Szczepanik
2019 Pełny tekst Journal of KONES
The process of the design of the 1MW steam turbine includes designing the stator and rotor blades, the steam turbine inlet and exit, the casing and the rotor. A turbine that operates at rotation speeds other than 3000 rpm requires a gear box and generator with complex electronic software. This paper analyses the efficiency of eight turbine variants, including seven inlet geometries and three stages of stator as well as an eight variant with one of the inlets, all three stages and an outlet.
Influence of microwave treatment conditions of GTR on physico-mechanical and structural properties of NBR/NR/GTR composites
- J Canavate
- Xavier Colom
- Mohammad Saeb
- Marta Przybysz-Romatowska
- Łukasz Zedler
- Krzysztof Formela
2019 Pełny tekst AFINIDAD
The increasing amount of tires used in the industry induces the researchers to find alternatives to the recycling of the end-of-life tires. Several alternatives in order to application of ground tire rubber GTR include their incorporation as a filler in composites. The main issue in this approach is the lack of compatibility between GTR and polymer matrix. In order to solve this problem the devulcanization by microwaves has been proposed as an interesting approach in order to improve the subsequent crosslinking when the GTR is incorporated to an elastomeric matrix and subsequently co-vulcanizated. In this article a blend formed by natural rubber NR and nitrile butadiene rubber NBR has been proposed as a suitable matrix for composites including GTR. In order to improve the compatibility, the GTR was treated by microwaves prior to its application as semi-reinforcement in rubber matrix. The results indicate that the pretreatment of GTR by microwaves improves the cross-linking and co-vulcanization of used elastomers, what have a positive influence on the mechanical behaviour and microstructure of the NR/NBR/GTR composites evaluated by tensile tests, equilibrium swelling, Thermo Gravimetric Analysis (TGA), Infrared Spectroscopy (FTIR) and Scanning Electronic Microscopy (SEM).
Influence of orientational disorder on the optical absorption properties in hybrid metal‐halide perovskite CH3NH3PbI3. A combined DFT/TD‐DFT and experimental study.
- Adam Miłosz
- Głowienka Damian
- Jędrzej Szmytkowski
- Galagan Yulia
- Julien Guthmuller
2019 Pełny tekst CHEMPHYSCHEM
An experimental and theoretical investigation is reported to analyze the relation between the structural and absorption properties of CH3NH3PbI3 in the tetragonal phase. More than 3000 geometry optimizations were performed in order to reveal the structural disorder and to identify structures with the lowest energies. The electronic structure calculations provide an averaged band gap of 1.674 eV, which is in excellent agreement with the experimental value of about 1.6 eV. The simulations of the absorption spectrum for three representative structures with lowest energy reproduced the absorption shoulders observed in the experimental spectra. These shoulders are assigned to excitations having similar orbital characters and involving transitions between hybridized 6s(Pb)/5p(I) orbitals and 6p(Pb) orbitals. The geometries of the three structures were analyzed and the effects of the inorganic frame and the CH3NH3+ cations on the absorption properties were estimated. It was found that both changes in the inorganic frame and the CH3NH3+ cations orientations impact the absorption spectra, by modifying the transitions energies and intensities. This highlights the role of CH3NH3+ cation in influencing the absorption properties of CH3NH3PbI3 and demonstrates that CH3NH3+ cation is one of the key elements explaining the broad and nearly constant absorption spectrum in the visible range.
Influence of Parameters of Laser Beam Welding on Structure of 2205 Duplex Stainless Steel
- Michał Landowski
2019 Pełny tekst Advances in Materials Science
Laser welding is used in modern industry, having many advantages comparing to traditional welding technologies. Nowadays, industry sectors such as shipbuilding, automotive and aviation can’t be imagined without laser processing technologies. Possibility of increase of welded joint properties, autogenous welding and high level of process automation makes the technology of laser welding perspective part of the industry. Physical multidimensional processes complexity requires a deeper understanding of the impact of laser welding parameters on the quality of welded joints for industrial implementation. The paper presents results of microstructure investigations of laser beam welded stainless steel under various welding parameters. Welded joints was achieved by Ytterbium fiber laser type without the use of the filler material. Material for test was 2205 ferritic-austenitic duplex stainless steel (DSS) plates with thickness of 8 mm in delivery condition. The objectives of this research was to investigate influence of laser welding parameters on weld geometry of buttwelded joints. Investigations of bead shape revealed correlation between laser beam focus position and weld penetration depth.
Influence of Selected Saccharides on the Precipitation of Calcium-Vaterite Mixtures by the CO2 Bubbling Method
- Donata Konopacka-Łyskawa
- Natalia Czaplicka
- Barbara Kościelska
- Marcin Stanisław Łapiński
- Jacek Gębicki
2019 Pełny tekst Crystals
Calcium carbonate is a compound existing in living organisms and produced for many biomedical applications. In this work, calcium carbonate was synthesized by a CO2 bubbling method using ammonia as a CO2 absorption promotor. Glucose, fructose, sucrose, and trehalose were added into the reaction mixture to modify characteristics of precipitated calcium carbonate particles. To determine the polymorphic form of produced calcium carbonate particles, Fourier transform infrared spectroscopy (FTIR-ATR) and X-ray diffraction (XRD) analysis were performed. Scanning electron microscopy (SEM) was used to estimate the size and shape of produced particles. Mixtures of vaterite and calcite were synthesized in all experiments. The percentage content of the vaterite in the samples depended on used additive. The highest concentration of vaterite (90%) was produced from a solution containing sucrose, while the lowest concentration (2%) was when fructose was added. Saccharides affected the rate of CO2 absorption, which resulted in a change in the precipitation rate and, therefore, the polymorphic composition of calcium carbonate obtained in the presence of saccharides was more varied.
Influence of silver-core gold-shell nanoparticle parameters on the variation of surface-enhanced Raman spectra
- Maciej Wróbel
- Katarzyna Karpienko
- Marcin Marzejon
- Filip Sadura
- Soumik Siddhanta
- Ishan Barman
- Janusz Smulko
2019 Pełny tekst Proceedings of SPIE
The detection of molecules by surface-enhanced Raman spectroscopy (SERS) is dependent on the nanomaterial used to induce the enhancement effect. This depends on a variety of parameters of the substrate such as the metal used for their creation, their shape, size and size distribution, concentration, as well as the parameters of the solution, such as packing of the nanoparticles, the complexity of the sample, the solvent, etc. It is most crucial, that the parameters are kept constant to provide uniformity of the enhancement. this is crucial for the development of SERS as a reliable and quantitative technique for bioanalysis. Here, we have developed the silver-core and gold-shell nanoparticles, to serve as the enhancement material. The fabrication phase involved constant concentrations of chemicals stability of the solution physical parameters like stirring and heating, and differed only in the perturbation of the reagents addition kinetics. These nanoparticles were investigated further with their ability to measure the solutions of 2-naphtalenethiol in DMSO, as model for testing the variability of the signal due to the enhancement and the kinetics of the nanoparticle-sample solution during a routine Raman measurement procedure. The results indicate vast difference in the preference of the 2-naphthalenethiol to come into contact with the nanoparticles and the partial enhancement of DMSO in most cases, with an almost complete by-pass of the solvent and direct detection of the 2-naphthalenethiol in one case. Moreover, the kinetics of the measurement solution, or its stability during measurement, is provided.
Influence of soil–structure interaction on seismic pounding between steel frame buildings considering the effect of infill panels
- Hytham Elwardany
- Ayman Seleemah
- Robert Jankowski
- Saher El-Khoriby
2019 Pełny tekst Bulletin of Earthquake Engineering
The present research aims to study the influence of the soil-structure interaction (SSI) and existence or absence of masonry infill panels in steel frame structures on the earthquake-induced pounding-involved response of adjacent buildings. The study was further extended to compare the pounding-involved behavior versus the independent behavior of structures without collisions, focusing much on dynamic behavior of single frames. The effect of SSI was analyzed by assuming linear springs and dashpots at the foundation level. The infill panels were modeled using equivalent diagonal compression struts. The steel frames were assumed to have elastic-plastic behavior with 1% linear strain hardening. The dynamic contact approach was utilized to simulate pounding between the adjacent buildings. Nonlinear finite element analysis was performed for two adjacent multi-story structures with four different configurations representing cases that can exist in reality. The seismic response of the studied cases generally emphasized that ignoring the soil flexibility and/or the contribution of the infill panels may significantly alter the response of adjacent structures. This may result in a false expectation of the seismic behavior of buildings exposed to structural pounding under earthquake excitation.
Influence of steam cooking on pro-health properties of Small and Large variety of Momordica charantia
- Martyna Lubinska-Szczygeł
- Anna Różańska
- Jacek Namieśnik
- Tomasz Dymerski
- Arkadiusz Szterk
- Patraporn Luksirikul
- Suchada Vearasilp
- Elena Katrich
- Shela Gorinstein
2019 FOOD CONTROL
Steam cooking is one of the most common preparations of Momordicacharantia dishes. This method improved the tastiness of the fruits but at the same time, some changes occurred in the volatile and non-volatile parts of their food matrices. In this study, for the first time these properties were correlated with the found substances affecting the bioactivity of this fruit. Two varieties of Momordicacharantia were analysed and compared. It was possible to differentiate both types of fruits using two-dimensional gas chromatography and time-of-flight mass spectrometry (GC×GC-TOF-MS) as well as to assess botanical and geographical origin. In the case of volatiles, 212 chemical compounds were tentatively identified, which can be classified into seven chemical classes, such as aldehydes, alcohols, esters, ketones, terpenes, hydrocarbons. Furthermore, 16 of them were quantified and calculated in terms of OAV and ROC values. Bioactive substances (polyphenols, flavonoids, tannins and flava- nols) and the values of antioxidant capacities by four radical scavenging assays (DPPH, CUPRAC FRAP, ABTS) were determined and compared in water and methanol extracts of Chinese and Indian varieties. It was proven that steam cooked Chinese variety has greater value due to its flavour than Indian variety and consists more volatile, non-volatile and bioactive constituents with high antioxidant effect. The binding properties of poly- phenols to HSA were relatively high in comparison with other plants. A strong positive correlation of binding properties and bioactivity of Momordicacharantia was estimated. One of the volatiles, namely citronellol, has key importance in respect of antidiabetic effect of Momordica charantia Chinese variety. This study indicates pro- health preponderance of Chinese variety over Indian variety and confirms that steam cooking is in lines with the canons of safe food preparation.
Influence of steel brackets supporting crane runway girders structure on the stress distribution in the brackets
- Natalia Korcz-Konkol
- Piotr Iwicki
- Elżbieta Urbańska-Galewska
2019 Pełny tekst
The paper presents a numerical analysis of steel brackets supporting a double-span crane runway girders. The purpose of the study was to assess the new structural solution based on the stress distribution in the brackets. In order to simplify the connection, the bottom flange of the crane runway girder is based directly on the upper flange of the bracket. As a result, the support reaction is no longer applied in the plane of the bracket web, but it is carried as ununiform pressure. Known analytical methods are not sufficient to assess the level of the bracket material effort due to the mechanism of the forces transmission. That is why the FE analysis was performed. Twisting of the bracket caused by eccentric load (in addition to the biaxial bending) was observed. What is more it occurred that transverse stiffeners in the bracket structure generate high stress.
Influence of Storage Time and Temperature on the Toxicity, Endocrine Potential, and Migration of Epoxy Resin Precursors in Extracts of Food Packaging Materials
- Błażej Kudłak
- Natalia Jatkowska
- Paweł Kubica
- Galina Yotova
- Tsakovski Stefan
2019 Pełny tekst MOLECULES
The aim of the present study was to establish a standard methodology for the extraction of epoxy resin precursors from several types of food packages (cans, multi-layered composite material, and cups) with selected simulation media (distilled water, 5% ethanol, 3% dimethyl sulfoxide, 5% acetic acid, artificial saliva) at different extraction times and temperatures (factors). Biological analyses were conducted to determine the acute toxicity levels of the extracts (with Vibrio fischeri bacteria) and their endocrine potential (with Saccharomyces cerevisiae yeasts). In parallel, liquid chromatography-tandem mass spectrometry was performed to determine levels of bisphenol A diglycidyl ether (BADGE), bisphenol F diglycidyl ether (mixture of isomers, BFDGE), ring novolac glycidyl ether (3-ring NOGE), and their derivatives. The variation induced by the different experimental factors was statistically evaluated with analysis of variance simultaneous component analysis (ASCA). Our findings demonstrate the value of using a holistic approach to best partition the effects contributing to the end points of these assessments, and offer further guidance for adoptingsuch a methodology, thus being a broadly useful reference for understanding the phenomena related to the impacts of food packaging materials on quality for long- and short-term storage, while offering a general method for analysis.
Influence of the Delay in Monitor System on the Motor Coordination of Musicians while Performing
- Szymon Zaporowski
- Maciej Blaszke
- Dawid Weber
- Marta Stefaniak
2019
This paper provides a description and results of measurements of the maximum acceptable value of delay tolerated by a musician, while playing an instrument, that does not cause de-synchronization and discomfort. First, methodology of measurements comprising audio recording and a fast camera is described. Then, themeasurement procedure for acquiring the maximum value of delay conditioning comfortable playing is presented. Results of musician’s response while playing an instrument along with a delayed signal reproduced from the monitor system are shown. Finally, a presentation of the highest values of delays for musicians playing different instruments is given along with a detailed discussion on the methodology used
Influence of the electrosynthesis conditions on the spontaneous release of anti-inflammatory salicylate during degradation of polypyrrole coated iron for biodegradable cardiovascular stent
- Karolina Cysewska
- Jakub Karczewski
- Piotr Jasiński
2019 ELECTROCHIMICA ACTA
In this work, the spontaneous release of anti-inflammatory salicylate from polypyrrole (PPy) coated iron has been studied during degradation of the material in phosphate buffer saline at 37 C. The sodium salicylate was incorporated into PPy in a one-step electropolymerization process. The influence of the synthesis conditions such as sodium salicylate concentration, pyrrole concentration and deposition charge on drug release profile has been investigated. The morphology, surface roughness and redox properties of PPy/Fe have been also studied. The drug release was studied by UV-Vis spectrophotometer with flow cuvette connected to the electrochemical cell, which provided continuous study of the released dopant. As a result, reliable and quantitative study of salicylate release from PPy coated iron was attained.Depending on the synthesis conditions the concentration of the salicylate released was in the range of 83-183 mM/cm2 after 21 h of immersion. The rate of drug release of 10-11mM/h was the highest at the beginning after immersion (1-2 h), then it gradually decreased and finally it reached the lowest value of approximately 0.3 mM/h at the end of the process.
Influence of the ionic strength on the amyloid fibrillogenesis of hen egg white lysozyme
- Jarosław Wawer
- Michał Szociński
- Marcin Olszewski
- Rafał Piątek
- Mateusz Naczk
- Joanna Krakowiak
2019 INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
The study investigates the role of the electrostatic interactions in the fibrillation of the hen egg white lysozyme (HEWL). In order to achieve this aim the influence of the cations Na+, Mg2+ and Al3+ on the amyloid fibril formation and amorphous aggregation was tested. The amyloids are formed in the solution without added salt but the Thioflavin T fluorescence gives the false-negative result. In these conditions, the HEWL fibrils are long and curvy. If the ionic strength of the solution is sufficiently high, the formed amyloids are shorter and fragmented. Our study shows that the addition of the aluminium salt promotes protein fibrillation. The amorphous aggregation dominates in the high concentration of electrolyte. The in vitro amyloid fibril formation seems to be regulated by universal mechanisms. The theories implemented in the polymer science or for colloidal solutions give the qualitative description of the aggregation phenomena. However, the specific interactions and the additional effects (e.g. fibril fragmentation) modulate the amyloidogenesis.
Influence of the low ambient temperature on the start-up process of hydraulic pumps
- Ryszard Jasiński
2019
Starting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of pressure drop in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump working chambers with oil and reducing volumetric efficiency. Starting of cooled hydraulic pump in low temperatures may occur when pump is supplied either with oil of the same ambient temperature or with the oil warmed to higher temperature. During start-up of a hydraulic pump in thermal shock conditions, parts warm up in a nonuniform way, due to varying material and shape properties. This causes change of clearances between the co-operating elements and may lead to faulty operation of hydraulic pump or to its break-down. Experimental tests of pumps during start-up in low ambient temperatures, were performed in the Hydraulics Laboratory of the Faculty of Mechanical Engineering of the Gdańsk University of Technology. The Laboratory is equipped with multipump supply devices with oil temperature stabilization, devices for testing hydraulic components as well as a system for measuring and recording mechanical, hydraulic and thermal quantities. In low temperature chamber it was possible to cool down hydraulic components to –25 °C. The supply oil temperature was kept in the range from 20 to 60 °C (usually at 50 °C) by means of oil temperature stabilizing system.
Influence of the shoe type on the ground reaction forces
- Małgorzata Klepczyńska
- Bartłomiej Zagrodny
- Wiktoria Wojnicz
- Michał Ludwicki
- Jan Awrejcewicz
2019 Pełny tekst
The aim of this work was to estimate a relationship between the type of the footwear and ground reactions. Differences in medio-lateral, anterior-posterior and vertical reactions are compared for different shoe-types for male and female volunteers. Each of the participants gait was recorded in case of different shoes and without them, also stabilograms were analyzed. Results revealed differences in ground reaction forces for different shoe-types and its influence on static stability.
Influence of Thermal Imagery Resolution on Accuracy of Deep Learning based Face Recognition
- Maciej Szankin
- Alicja Kwaśniewska
- Jacek Rumiński
2019 Pełny tekst
Human-system interactions frequently require a retrieval of the key context information about the user and the environment. Image processing techniques have been widely applied in this area, providing details about recognized objects, people and actions. Considering remote diagnostics solutions, e.g. non-contact vital signs estimation and smart home monitoring systems that utilize person’s identity, security is a very important factor. Thus, thermal imaging has become more and more popular, as it does not reveal features that are often used for person recognition, i.e. sharp edges, clear changes of pixel values between areas, etc. On the other hand, there are much more visible light data available for deep model training. Taking it into account, person recognition from thermography is much more challenging due to specific characteristics (blurring and smooth representation of features) and small amount of training data. Moreover, when low resolution data is used, features become even less visible, so this problem may become more difficult. This study focuses on verifying whether model trained to extract important facial embedding from RGB images can perform equally well if applied to thermal domain, without additional re-training. We also perform a set of experiments aim at evaluating the influence of resolution degradation by down-scaling images on the recognition accuracy. In addition, we present deep super-resolution (SR) model that by enhancing donw-scaled images can improve results for data acquired in scenarios that simulate real-life environment, i.e. mimicking facial expressions and performing head motions. Preliminary results proved that in such cases SR helps to increase accuracy by 6.5% for data 8 times smaller than original images. It has also been shown that it is possible to accurately recognize even 40 volunteers using only 4 images per person as a reference embedding. Thus, the initial profiles can be easily created in a real time, what is an additional advantage considering a solution setup in a new environment.
INFLUENCE OF WRONGLY ASSUMED PROBABILITY DISTRIBUTION ON THE UNCERTAINTY OF RESISTANCE MEASUREMENT BY TECHNICAL METHOD
- Stanisław Szczesny
- Anna Golijanek-Jędrzejczyk
- Dariusz Świsulski
2019 Pełny tekst Poznan University of Technology Academic Journals. Electrical Engineering
The paper presents studies on the influence of probability distributions on the expanded uncertainty of the resistance measurement. Choosing the correct probability distribution is very important to estimate of measurement uncertainty. The most commonly used distribution is the rectangular distribution. The paper presents the results of analysis of the resistance measurement uncertainty using the technical method of two resistances: 1 Ω and 100 GΩ using different measuring equipment. The analysis of the uncertainty measurement of resistance was carried out repeatedly, each time assuming a different probability distribution of measuring instruments (normal, rectangular, triangular or trapezoidal). The results of the research presented in the article show that the influence of the assumed probability distributions on the result of the measurement uncertainty analysis is significant and results discrepancies can reach up to 30%.
Influence of YARN Schedulers on Power Consumption and Processing Time for Various Big Data Benchmarks
- Krzysztof Drypczewski
- Jerzy Proficz
- Andrzej Stepnowski
2019 Pełny tekst TASK Quarterly
Climate change caused by human activities can influence the lives of everybody onthe planet. The environmental concerns must be taken into consideration by all fields of studyincludingICT. Green Computing aims to reduce negative effects of IT on the environment while,at the same time, maintaining all of the possible benefits it provides. Several Big Data platformslike Apache Spark orYARNhave become widely used in analytics and High-PerformanceComputing systems due to the reliability and usability of Map Reduce implementations. Theauthors research the power consumption and energy efficiency of HadoopYARNschedulers usingApache Spark under three different workloads. The test cases include: sorting large binary files,counting unique words in large text files and processing satellite imagery from the Sentinel-2mission. The presented results show small (2%–11%) but distinct differences in the powerconsumption ofFIFOandFAIRschedulers