2019 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2019

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Terpeny w powietrzu wewnętrznym. Cz. II. Analityka terpenów i produktów ich utleniania.
- Klaudia Pytel
- Renata Marcinkowska
- Bożena Zabiegała
2019 Analityka: Nauka i Praktyka
Kluczowe wydaje się poznanie dokładnego składu chemicznego Wtórnego Aerozolu Organicznego (SOA) obecnego w powietrzu wewnętrznym oraz określenie konkretnych mechanizmów odpowiedzialnych za jego powstawanie.
Testowanie wybranych kryteriów zabezpieczeniowych przekaźników zabezpieczeniowych SN z wykorzystaniem standardu IEC 60255
- Mirosław Włas
- Kacper Chyła
- Filip Pankowiak
- Tomasz Bednarczyk
2019 Pełny tekst Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
Badania oparte na standardzie IEC 60255 mają postać szeregu testów wymaganych oraz opracowanych na podstawie owego standardu. Testom zostały poddane wybrane funkcje zabezpieczeniowe zaimplementowane w testowanych przekaźnikach zabezpieczeniowych REF 615 firmy ABB. Celem było porównanie otrzymanych wartości z deklarowanymi przez producenta oraz wyznaczenie zależności w funkcji rożnych, zmiennych warunków testowych.
Tests for lapping of flat surfaces of ceramic elements with forced dosing of abrasive slurry
- Adam Barylski
- Maciej Gniot
2019 Pełny tekst Mechanik
Przedstawiono zagadnienia dotyczące systemu wymuszonego dawkowania zawiesiny ściernej w docieraniu jednotarczowym powierzchni płaskich. Opisano zalety takiego systemu dozowania płynnej zawiesiny ściernej. Omówiono wybrane wyniki badań docierania elementów z ceramiki technicznej. Analizowano wpływ podstawowych warunków dawkowania zawiesiny na ubytek liniowy próbek.
The Accuracy of a Marine Satellite Compass under Terrestrial Urban Conditions
- Paweł Dąbrowski
- Cezary Specht
- Andrzej Felski
- Władysław Koc
- Andrzej Wilk
- Krzysztof Czaplewski
- Krzysztof Karwowski
- Krzysztof Jaskólski
- Mariusz Specht
- Piotr Chrostowski
- Jacek Szmagliński
2019 Pełny tekst Journal of Marine Science and Engineering
When used at sea, satellite compasses are capable of determining the course of a sailing vessel with high accuracy. It is dicult to verify the accuracy declared by the device manufacturer under such conditions, as it is dicult to define a reliable reference. This study analyses the accuracy of the satellite compass in an urban setting, with the satellite signal being obscured to various extents. It is an important point in the study to refer the measurement results to a reference route, which is the axis of a tramway track, determined by the precise GNSS RTK method. The measurement data were processed in the original software developed by the authors. The results demonstrate a high 2D positioning accuracy with low height determination accuracy. The course determination errors exceed the limit values declared by the manufacturer. However, specific measurement conditions must be taken into account, which dier considerably from the typical applications of a satellite compass.
The Analysis of Overall Ship Fuel Consumption in Acceleration Manoeuvre using Hull-Propeller-Engine Interaction Principles and Governor Features
- Hamid Zeraatgar
- Mohammad Ghaemi
2019 Polish Maritime Research
The problem of reduction of greenhouse gas emissions in shipping is currently addressed by many research works and related industries. There are many existing and visionary technologies and ideas, which are conceptually defined or practically realised. This goal can be achieved in different ways, and reducing fuel consumption is one of the major methods. In these circumstances, the aim of this study is to analyse the possibility of fuel consumption reduction by using an alternative control strategy for low-speed marine diesel engines which would take into account the interactions between hull, propeller and main engine. For this purpose, a mathematical model including ship hull and propulsion system is developed. A case study is conducted for a ship for which the results of both the ship hull and screw propeller model tests are available. A low-speed two-stroke diesel engine is then selected for the considered ship. Two different governors are included in the model and their parameters are changed to investigate the dynamic behaviour of the system when simulating the forward acceleration mode in calm sea conditions. The research is mainly focused on variations of fuel consumption by the ship passing a certain distance to reach the nominal constant speed. It is concluded that, for a given travel distance, it is possible to save considerable amount of fuel at the expense of slight increase of journey time.
The ancient formula of master-apprentice relevance in contemporary architecture education.
- Ksenia Piątkowska
- Elżbieta Ratajczyk-Piątkowska
2019 Pełny tekst World Transactions on Engineering and Technology Education
The universalization of the methodology for determining the quality of European higher education exposes the aspect of supporting the student in the education process, which takes the form of tutoring or supervising - a modern form of ancient master-apprentice relationship. The 'master' in architectural education has lawful building qualification and is a member in national architect association - a sine qua non with respect to legally working as an architect. The 'master' shapes apprentice's attitudes, explicates professional ethics issues, puts across patterns of acceptable behavior related to the indefeasible intellectual and creative property rights. Maybe for better the formula of master-apprentice relation should be carried on in design offices or workshops instead of education institutions?
The Anti-Staphylococcal Potential of Ethanolic Polish Propolis Extracts
- Katarzyna Grecka
- Piotr Kuś
- Piotr Okińczyc,
- Randy Worobo
- Justyna Walkusz
- Piotr Szweda
2019 Pełny tekst MOLECULES
Abstract: The principal objective of this study was to determine the anti-staphylococcal potential of ethanol extracts of propolis (EEPs). A total of 20 samples of propolis collected from apiaries located in different regions of Poland were used in the study. The two-fold broth microdilution method revealed some important differences in the antimicrobial activity of investigated EEPs. Up to the concentration of 4096 µg/mL no activity was observed against Gram-negative bacteria (E. coli and P. aeruginosa). Staphylococci exhibited much higher susceptibility. The highest efficiency observed for EEP12 and EEP20 (MIC values ranged between 32 and 256 µg/mL). However, the achievement of bactericidal effect usually required higher concentrations. In the case of clinical isolates of S. aureus MBC values for EEP12 and EEP20 ranged from 512 to 1024 µg/mL. The HPLC analysis revealed that these two products contained a higher concentration of flavonoids (flavonols, flavones, and flavanones) compared to other investigated EEPs. In checkerboard test, a synergistic anti-staphylococcal effect was observed for the action of EEP20 in combination with amikacin, kanamycin, gentamycin, tetracycline, and fusidic acid (all these antibiotics inhibit protein synthesis). Moreover, the investigated EEPs effectively eradicated staphylococcal biofilm. The obtained results clearly confirm the high anti-staphylococcal potential of propolis harvested in Polish apiaries.
The Application of Granulated Expanded Glass Aggregate with Cement Grout as an Alternative Solution for Sub-Grade and Frost-Protection Sub-Base Layer in Road Construction
- Marzena Kurpińska
- Beata Grzyl
- Marek Pszczoła
- Adam Kristowski
2019 Pełny tekst Materials
The purpose of the research was to assess the possibility of using granulated expanded glass aggregate (GEGA) with cement grout as a replacement of a sub-grade and frost-protection layer, made of natural fine aggregates (NATU), stabilized with a hydraulic binder. Instead of traditional parts of the road construction, such as the sub-grade and frost-protection layer with the application of fine aggregate, stabilized with cement, the authors propose only one layer, made of lightweight water-permeable material, containing GEGA with a grain size from 8 to 11.2 mm. In the article the authors present the physical properties of the materials, applied for the road layers, the properties of the fine aggregate, stabilized with cement, and those of the cement composite with GEGA as an alternative solution. The laboratory test results of fine aggregates, stabilized with cement and of cement composites with GEGA, are presented. Porosity, volume density, compressive strength, and frost resistance are being researched. The results of those tests are meant to play an essential role in designing the thickness of road layers. Dierent types of pavement structure (asphalt and concrete) and dierent values of road load are being considered in the given work. The paper is concluded with considerations on an innovative solution, involving the use of ecological materials.
The application of Monod equation to denitrification kinetics description in the moving bed biofilm reactor (MBBR)
- L Kopec
- A Kopec
- Jakub Drewnowski
2019 Pełny tekst International Journal of Environmental Science and Technology
In this paper, the kinetic constants Vmax and KCOD occurring in the Monod equation, which describe the denitrification process in the moving bed, are determined. For this purpose, a laboratory moving bed biofilm reactor (MBBR) was used. The filling of the reactor consisted of EvU Perl carriers. The experiment was carried out with an excess of nitrate, and denitrification rate was dependent on the concentration of external organic carbon, which constituted the Brennta Plus preparation. Determination of constants was made by Hofstee–Eadie method, whereby there was obtained: Vmax = 0.78 g NO3−–N/g D.M./day and KCOD = 16.97 g O2/m3. The new Monod equation was verified using MBBR constructed on an industrial scale in wastewater treatment plant in Gronowo Górne (Poland). After joining the MBBR to the technological system and after a period of biomass adaptation, total nitrogen removal efficiency increased from 53.5 to 86.0%. The results of the research have been discussed with several similar researches.
THE APPLICATION OF PHENOMENOLOGICAL METHODOLOGY FOR DESIGNING PILE FOUNDATION IN PORT STRUCTURES
- Paweł Więcławski
2019 Pełny tekst Polish Maritime Research
It is of utmost importance in the design process that a suitable, safe and concurrently economic solution be chosen. Issues connected with foundations require adopting a special approach. Soil is a composite medium, and it is essential to describe as precisely as possible the interaction taking place between the subgrade and the structure. There are many design methods of pile foundation that are based on in-situ test of soils. As a result of incessant development of the pile installation technology, the results obtained with design methods used to date do not assure the required accuracy, and consequently the values of pile load capacity are not sufficiently accurate. A partial solution to this problem may be applying the observation method. Based on assumptions of phenomenology as a science that enable cognition of natural and mathematical phenomena, a procedure has been developed for projecting loading-settlement dependencies for Vibro piles installed in port areas in Poland. Those areas are characterised by similar soil and water conditions, as well as soil genesis and parameters. This procedure enables estimating the limit of load capacity values with much better accuracy than the hitherto used direct methods. The full range of the s(Q) function also enables the possibility of designing structures allowing for stringent criteria of admissible settlements having a specified value.
The authenticity in social media. Club and football players’ relations
- Agnieszka Firgolska
- Wioleta Kucharska
2019 Pełny tekst
The authenticity in social media is one of the crucial factors of brands success. In the era of fake news, illusions, manipulations or other artificial attributes of the virtuality and reality today it is a real source of value. The presented study aims to verify how football club and football players’ brands’ authenticity influence attitudinal loyalty in social media. Findings proved that the authenticity is something social media users appreciate. The more authentic football’s brands are the higher level of attitudinal loyalty towards general football as sports category is observed. The football brands authenticity is important for the whole football industry success. Scientific implications suggest that club and football players relations are more complex and require deeper theoretical studies to present the full picture of brands' authenticity relations in social media.
The bismuth vanadate thin layers modified by cobalt hexacyanocobaltate as visible-light active photoanodes for photoelectrochemical water oxidation
- Konrad Trzciński
- Mariusz Szkoda
- Kamil Szulc
- Mirosław Sawczak
- Anna Lisowska-Oleksiak
2019 ELECTROCHIMICA ACTA
Bismuth vanadate thin films deposited using the pulsed laser deposition technique were modified using cobalt hexacyanocobaltate (Cohcc). The 2-step method of Cohcc nanocubes preparation was applied: i) metallic cobalt deposition and ii) cobalt electrooxidation in Co(CN)63− containing electrolyte. The presence of CN stretching vibrations was confirmed by Raman spectroscopy. The energy band gap was equal to 2.5 eV and was estimated using UV–Vis spectroscopy. The presence of Cohcc did not clearly affect the absorbance ability of tested films. Electrodes were tested as photoanodes for water splitting. It was shown that electrocatalytical properties of Cohcc in the oxygen evolution reaction strongly affect the photocurrent generated during FTO/BiVO4/Cohcc illumination. A significant, almost 1 V, shift of the onset potential towards lower potential was achieved. The role of Cohcc has been discussed on the basis of electrochemical and photoelectrochemical measurements.
The Caucasian flora: a still-to-be-discovered rich source of antioxidants
- Naira Sahakyan
- Margarit Petrosyan
- Izabela Koss-Mikołajczyk
- Agnieszka Bartoszek-Pączkowska
- Tamara Gabour Sad
- Muhammad Jawad Nasim
- Maia Vanidze
- Aleko Kalandia
- Jacob Claus
- Armen Trchounian
2019 Pełny tekst FREE RADICAL RESEARCH
Cellular redox homeostasis is a state of balance between the formation of Usually Reactive Oxygen and / or Nitrogen Species (ROS/RNS), endogenous antioxidant defence systems, and exogenous dietary antioxidants. The disturbance of redox homeostasis, by the overproduction of endogenous ROS/RNS, may increase the risk of development of so-called civilisation diseases. The solution seems to be either the increased production of endogenous or consumption of exogenous antioxidants. Plant-borne antioxidants act via different chemical and molecular mechanisms, such as decreasing the level of oxidative damage in cells directly by reacting with ROS/ RNS or indirectly – by inhibition of the activity and expression of free radical generating enzymes or by enhancing the activity or expression of intracellular antioxidant defence enzymes. Despite the fact that the Caucasian flora is rich of health promoting edible/medicinal plants, recent studies concerning the biological activity of these plants are very scarce. This review is summarising the state-of-art on the health-promoting potential of plants representing the Caucasian flora, whose antioxidant capacity have been investigated in various in vitro models.
The Central European GNSS Research Network (CEGRN) dataset
- J. Zurutuza
- Alessandro Caporali
- M. Bertocco
- M. Ishchenko
- O. Khoda
- H. Steffen
- Mariusz Figurski
- E. Parseliunas
- S. Berk
- Grzegorz Nykiel
2019 Pełny tekst Data in Brief
The Central European GNSS Research Network (CEGRN) collects GNSS data since 1994 from contributors which today include 42 Institutions in 33 Countries. CEGRN returns a dataset of coordinates and velocities computed according to international standards and the most recent processing procedures and recommendations. We provide a dataset of 1229 positions and velocities resulting from 3 or more repetitions of coordinate measurements of each site over 4 or more years. The velocity data result from a combination of eight multiyear, partially overlapping networks, using 234 stations of class A of the European Permanent Network (EPN) for alignment to the ‘European Fixed’ ETRF2000 Reference Frame. The rms (root mean square) of the 8 individual contributions to the combined solution, after a 7 – parameter Helmert transformation, is less than 5 mm in the observation period 1996–2017. This combined CEGRN network maintains the origin coincident with that of the ETRF2000 reference frame to within 1.8 mm rms for the entire period of analysis. The mean positions and velocities of common EPN Class A and CEGRN stations differ by 0.0 ± 1.1, 0.5 ± 1.0 and 0.1 ± 2.7 mm for the coordinates and 0.06 ± 0.13, -0.07 ± 0.12, 0.38 ± 0.28 mm/yr for the velocities respectively for the North, East and Up components at epoch 2010.0.
The CFD analysis of influence the start of fuel injection (SOI) on combustion parameters and exhaust gas composition of the marine 4-stroke engine
- Jerzy Kowalski
2019 Pełny tekst Combustion Engines
The paper presents a theoretical analysis of the impact of injection timing on the parameters of the combustion process and the composition of exhaust gas from a 4-stroke engine designed to shipbuilding. The analysis was carried out based on a three-dimensional multi-zone model of the combustion process. This model has been prepared on the basis of properties of the research facility. The input data to the model were obtained through laboratory tests. Results of calculations showed that the change of the start of injection angle (SOI) from the value of 14 degrees before TDC to 22 degrees before TDC results in changes in the combustion rate and thus an increase in the temperature of the combustion process as well as the increase of nitric oxides fraction in the exhaust gas. Simultaneously the maximum combustion pressure increases also.
The comparison of betalain composition and chosen biological activities for differently pigmented prickly pear (Opuntia ficus-indica) and beetroot (Beta vulgaris) varieties
- Izabela Koss-Mikołajczyk
- Barbara Kusznierewicz
- Wiesław Wiczkowski
- Tomasz Sawicki
- Agnieszka Bartoszek-Pączkowska
2019 INTERNATIONAL JOURNAL OF FOOD SCIENCES AND NUTRITION
Betalains are a group of plant originated pigments with chemopreventive potential. The aim of this study was to relate the composition of betalains and chosen biological activities (antioxidant, cytotoxic, anti-genotoxic and influence on enzymatic activities) for extracts from differently pigmented varieties of prickly pear (yellow, orange and red) and beetroot (white and red). The assumption was that phytocomplexes of tested varieties of the same plant species would exhibit generally similar chemical composition differing mostly in betalain content, which will be reflected by their biological activity. Betalain composition analysis and antioxidant profiles confirmed that the content and composition of these pigments is strongly correlated with the antioxidant activity of tested plant extracts measured by spectrophotometric methods and CAA test. However, the results of determinations of other biological activities showed that in the case of actual plant foods, there was no simple relationship between betalain content or composition and chemopreventive potential.
The complete stereochemistry of the antibiotic candicidin A3 (syn. ascosin A3, levorin A3)
- Julia Borzyszkowska-Bukowska
- Paweł Szczeblewski
- Agnieszka Konkol
- Jakub Grynda
- Katarzyna Szwarc-Karabyka
- Tomasz Laskowski
2019 NATURAL PRODUCT RESEARCH
Herein, the stereostructure of the aromatic heptaene macrolide (AHM) antifungal antibiotic candicidin A3 (syn. ascosin A3, levorin A3) has been established upon the 2D NMR studies, consisting of DQF-COSY, TOCSY, ROESY, HSQC and HMBC experiments, as well as upon extensive molecular dynamics simulations. The geometry of the heptaenic chromophore was defined as: (22E, 24E, 26Z, 28Z, 30E, 32E, 34E). The previously unreported absolute configuration of the chiral centres of candicidin A3 was established as: (3R,9 R, 11 S, 13 S, 15 R, 17 S, 18 R, 19 S, 21 R, 36 S, 37 R, 38 S, 40 S, 41 S).
The computational methods in the development of a novel multianalyte calibration technique for potentiometric integrated sensors systems
- Marcin Urbanowicz
- Dorota G. Pijanowska
- Artur Jasiński
- Maria Bocheńska
2019 Pełny tekst JOURNAL OF SOLID STATE ELECTROCHEMISTRY
In recent years, integration and miniaturization of ion-selective electrodes (ISEs) have brought many benefits resulting in the possibility of simultaneous determination of the ions concentration in small volume samples. One of the key problems related to the preparation of potentiometric integrated sensors systems (PISSs) is a calibration procedure due to the necessity to calibrate each particular sensor separately. The main aim of the research was to develop a novel calibration method for PISSs fabricated with the use of an all-solid-state technology, which has been compared with other types of sensor calibration technique. The proposed algorithm concerns the method of calibration solutions composition determination for miniature ion-selective sensors before measuring in biological samples especially human saliva samples. This article also compares the parameters of ion-selective sensors for two types of PISSs, including ISEs based on gold (Au) and glassy carbon (GC) electrodes. In addition, a series of measurements was performed using PISS with Au-ISEs in samples of human saliva, which were preceded by different types of sensor calibration and compared with the results obtained with the clinical analyzer. Moreover, the effect of the viscosity of calibration solutions on the ISE parameters and the lifetime of the sensors were investigated.
The Concept of Geodetic Analyses of the Measurement Results Obtained by Hydrostatic Leveling
- Waldemar Kamiński
- Karolina Makowska
2019 Pełny tekst Geosciences
The article discusses the issue of hydrostatic leveling. Its application is presented in structural health monitoring systems in order to determine vertical displacements of controlled points. Moreover, the article includes a complete computation scheme that utilizes the estimation from observation differences, allowing the elimination of the influence of individual sensors’ systematic errors. The authors suggest two concepts of processing the measurement results depending on the sensors’ connection method. Additionally, the second concept is extended by the elements allowing the prediction of the displacements by means of Kalman filtering.
The concept of stream and system reliability on the example of the bakery industry
- Radosław Drozd
- Jan Piwnik
2019 Aparatura Badawcza i Dydaktyczna
This article presents a new concept of technological system reliability based on the analysis of the relationship of associations of elements of energy streams, matter, information, time and finance. The method of stream specification and the method of determining the reliability values of significant and supporting relationships are given. Relevant relationships between elements of system streams were defined as having one-time reliability value. Supportive relationships have a value between zero and one. Relevant relationships are determined based on research, experience and knowledge. Pss stream-system reliability is a scalar quantity, i.e. a number whose value lies between zero and unity. The size of Pss characterizes the entire system without being denied. Its average value in standard time tn expresses the efficiency of the production process. Pss is the quotient of the number of significant relationships to the sum of the significant and supporting relationships. The form of expression on Pss indicates how to optimize the process by increasing the number of relationships significant between the components of the system batch streams. The Pss concept was used in research into the production efficiency of bakery X operating within the MSCBI group. System analysis of the bakery allows a significant increase in the bread baking process reliability after using robotization. The concept of Pss stream-system reliability can be used to analyze the efficiency of technological processes and optimization in any production processes. This requires a detailed system analysis of such processes