Publications Repository - Gdańsk University of Technology

Page settings

polski
Publications Repository
Gdańsk University of Technology

Show publications from the year

Publications from the year 2016

Show all
  • The use of the static thermography in monitoring flap perfusion in breast reconstruction with TRAM flap
    • Szymon Kołacz
    • Mateusz Moderhak
    • Jerzy Jankau
    2016

    This paper shows results of the static thermography for intraoperative and postoperative imaging of TRAM flap perfusion. The results were compared with the clinical examination of flap perfusion. The study was conducted on a group of 38 female patients who underwent breast reconstruction.

  • The usefulness of birch saps from the area of Podkarpacie to produce birch syrup
    • Maciej Bilek
    • Marcin Olszewski
    • Michał Gostkowski
    • Ewa Cieślik
    2016 Biotechnology and Food Science

    In northern European countries, as well as in North America tree saps of maples and birches are used for the production of syrups. Birch syrups are characterized by a specific aromatic taste and can be used as an addition to sweets, desserts, salads and meats. Attention is paid to the health benefits of birch syrups, mainly for high mineral content. The aim of this study was to evaluate the usefulness of birch saps obtained from the area of Podkarpacie for birch syrup production. HPLC-ELSD system was used for analysing the sugar content in the birch tree saps from four localization. All the examined saps contained the monosaccharides as fructose and glucose. The presence of sucrose was found in eight per twenty tested saps. There weren’t statistical differences between the studied sites for the averages of total sugar concentration in the tree saps samples. The highest average amount of total sugar was found in the D sites (11.74 g/dm3), whereas the lowest in the C sites (7.66 g/dm3). Silver birch tree saps from the area of Podkarpacie offer perspectives to used for syrup production according to the US and Finnish criteria of profitability.

  • The Verification of the Usefulness of Electronic Nose Based on Ultra-Fast Gas Chromatography and Four Different Chemometric Methods for Rapid Analysis of Spirit Beverages
    • Paulina Wiśniewska
    • Magdalena Śliwińska
    • Jacek Namieśnik
    • Waldemar Wardencki
    • Tomasz Dymerski
    2016 Full text Journal of Analytical Methods in Chemistry

    Spirit beverages are a diverse group of foodstuffs. They are very often counterfeited which cause the appearance of low quality products or wrongly labelled products on the market. It is important to find a proper quality control and botanical origin method enabling the same time preliminary check of the composition of investigated samples, which was the main goal of this work. For this purpose, the usefulness of electronic nose based on ultra-fast gas chromatography (fast GC e-nose) was verified. A set of 24 samples of raw spirits, 33 samples of vodkas, and 8 samples of whisky were analysed by fast GC e-nose. Four data analysis methods were used. The PCA was applied for the visualization of dataset, observation of the variation inside groups of samples, and selection of variables for the other three statistical methods. The SQC method was utilized to compare the quality of the samples. Both the DFA and SIMCA data analysis methods were used for discrimination of vodka, whisky, and spirits samples. The fast GC e-nose combined with four statistical methods can be used for rapid discrimination of raw spirits, vodkas, and whisky and in the same for preliminary determination of the composition of investigated samples.

  • The work-family interface: Job demands, work engagement and turnover intentions of Polish nurses
    • Anna Maria Daderman
    • Beata Basińska
    2016

    A conflict between one's professional life and one's family life may lead to lower well-being both at work and home. Most nurses are women who have traditionally reconciled their professional life with family life. One aim of this study was to examine the relationships between the work-family conflict (WFC),the family-work conflict (FWC), and the perception of job demands (quantitative workload and interpersonal conflicts at work). We intended also to examine the components of work engagement (vigour, dedication, and absorption) and turnover intentions. Another aim was to determine whether the variables that we examined are important for turnover intentions. This study comprised Polish registered nurses. The following instruments were used:Work-Family Conflict and Family-Work Conflict Scales (Netemeyer, Boles, &McMurrian, 1996), the Interpersonal Conflict at Work Scale and Quantitative Workload Index (Spector & Jex, 1998), the Utrecht Work Engagement Scale(Schaufeli, Bakker, & Salanova, 2006), and measures of turnover intentions (intention to leave the present workplace and intention to leave the nursing profession). The score on the scale to measure WFC was positively related to perceived workload and to both turnover intentions, while negatively related to vigour. The WFC was experienced significantly more intensively than FWC. The perception of differences in mean scale scores of job demands had a moderate effect on the FWC and WFC, while differences in mean scale scores of vigour had a strong effect on the WFC. WFC, quantitative workload and a low level of dedication were significant predictors of the intention to leave the present workplace, while the level of job demands was a significant predictor of theintention to leave the nursing profession. The results are interpreted and discussed using Hobfoll's Conservation of Resources theory.

  • THEORETICAL POTENTIAL OF HYDROGEN PRODUCTION FROM TEXTILES WASTES IN POMERANIAN REGION BY MEANS OF DARK FERMENTATION
    • Gaweł Sołowski
    2016 Zeszyty Naukowe Gdańskiej Szkoły Wyższej

    Model has been developed for calculating theoretical mass of hydrogen produced from textile wastes by mean of dark fermentation. As vegetable fibres wastes were chosen two mostly used — cotton and linen (flax). As the synthethic carbohydrate rich fiber was chosen viscose. In the background there were introduced: problems of dark fermentation, characteristics of textile material structure. Additionally pathways of the process and ex- pressions of model are introduced. The model is presented in the part of results and conclu- sion. In section results and conclusions, numerical data of the model are presented and explained. Then results and conclusions of the analysis are shown. The textiles wastes are processed lignocellulose parts with low or no lignin fraction. The analysis of dark fermenta- tion of textile wastes is relevant step to improve utilization of lignocellulose wastes. Theo- retical hydrogen mass from Poland textile wastes is 5860 tonnes — 13% of the recent Lotos hydrogen demand.

  • Theory vs. practice. Searching for a path of practical education
    • Piotr Marczak
    2016 Full text General and Professional Education

    The introduction of a three-tier model of higher education (the Bologna model) has led to considerable changes in the 1st- and 2nd-tier technical courses at universities. At present, a student with a bachelor’s degree can be employed in his / her profession after completing only 7 semesters of study. A search is under way for methods of combining theoretical knowledge taught at universities with practical knowledge gained afterwards. This is accompanied by technological and economic transformations, creating the need for new programmes and teaching methods in order to keep graduates up to speed with the ever-changing global labour market. This paper summarizes attempts to incorporate real-life labour market experience intothe process of educating students in the Architecture Department. This has been achieved through a series of lectures by business owners delivering construction technologies, hands-on student training as well as student competitions organized by companies.

  • Thermal and Mechanical Properties of Microporous Polyurethanes Modified with Reduced Graphene Oxide
    • Michał Strankowski
    • Damian Włodarczyk
    • Łukasz Piszczyk
    • Justyna Strankowska
    2016 Full text International Journal of Polymer Science

    Microporous polyurethanes (MPU) were modified by adding 0.25%–1.25 wt% of reduced graphene oxide (RGO). The materials were prepared without solvent via in situ polymerization. From a technological point of view, it is very important to obtain functional materials by using reacting compounds only. The thermal characteristics of obtained MPU were investigated using TGA, DSC, and DMA techniques. In comparison to nonmodified microporous polyurethane, the thermal stability and mechanical properties of the modified systems have significantly improved. The temperature corresponding to the maximum degradation rate () for nanocomposites containing 1% and 1.25 wt% of RGO was 51°C higher than that observed for pure microporous PU system. The increase of tensile strength was also observed for matrix with the addition of 0.5 wt% RGO nanofiller.

  • Thermal Imaging Aided Assessment of a State of Equipment Under Test and its Protecting Elements
    • Stanisław Galla
    • Tomasz Lisewski
    • Agnieszka Mikołajczyk
    • Stanisław Abramik
    2016

    In the paper the investigation results using thermal imaging methods are presented. The examined is a state of equipment under test and its protecting components. The estimations are done for the chosen protecting elements during surge immunity testing. The results show that the thermal imaging methods are useful for early detection of possible damage of a device being tested

  • Thermal imaging in automatic rodent’s social behaviour analysis
    • Magdalena Mazur-Milecka
    2016

    Laboratory rodent social behaviour analysis is an extremely important task for biological, medical and pharmacological researches. In this work thermal images features that facilitate analysis are presented. Methods to distinguish objects on the basis of thermal distribution are tested. Actions of grooming or biting one rodent by another - important social behaviour incidents - are clearly visible in thermal images due to the saliva left on fur. Numerical parameters useful in detecting the occurrence of these actions are described. Recognition results are verified on the rats' social behaviour thermal images dataset.

  • Thermal performance of a prototype plate heat exchanger with minichannels under boiling conditions
    • Jan Wajs
    • Dariusz Mikielewicz
    • Elżbieta Fornalik-Wajs
    2016 Full text Journal of Physics : Conference Series

    To solve the problem and to meet the requirements of customers in the field of high heat fluxes transfer in compact units, a new design of plate heat exchanger with minichannels (minichannels PHE) was proposed. The aim was to construct a compact heat exchanger of high effectiveness for the purpose of household cogeneration ORC system. In this paper the experimental analysis of an assembled prototype of such compact heat exchanger was described. The attention was paid to its thermal performance and the heat transfer coefficients under the boiling conditions. Water and ethanol were chosen as working fluids. The maximal value of transferred heat flux was about 84 kW/m2, while of the overall heat transfer coefficient was about 4000 W/(m2K). Estimated values of heat transfer coefficient on the ethanol (boiling) side reached the level of 7500 W/(m2K). The results are promising in the light of future applications, for example in cogeneration ORC systems, however further systematic investigations are necessary.

  • Thermochemistry of rare earth perovskites Na3xRE0.67−xTiO3 (RE = La, Ce)
    • Dawei Feng
    • Pardha Saradhi Maram
    • Aleksandra Dorota Mielewczyk-Gryń
    • Alexandra Navrotsky
    2016 AMERICAN MINERALOGIST

    High-temperature oxide melt solution calorimetry using sodium molybdate (3Na2O·4MoO3) solvent at 973 K was performed for the Na3xRE0.67−xTiO3 (RE = La, Ce) perovskite series. The enthalpies of formation of lanthanum perovskites from oxides (La2O3, Na2O, TiO2), are −107.25 ± 2.56, −93.83 ± 6.06, −80.68 ± 5.93, and −33.49 ± 4.26 kJ/mol and enthalpies of formation from elements are −1614.05 ± 5.37, −1596.44 ± 7.68, −1594.03 ± 7.58, and −1577.56 ± 6.36 kJ/mol for Na0.459La0.522Ti0.999O3, Na0.454La0.523Ti0.994O3, Na0.380La0.567Ti0.980O3, and La0.692Ti0.979O3, respectively. The enthalpies of formation of cerium perovskites are −99.98 ± 5.78 and −45.78 ± 3.30 kJ/mol from oxides (Ce2O3, Na2O, TiO2), and −1611.34 ± 6.90 and −1602.06 ± 2.72 kJ/mol from elements for Na0.442Ce0.547Ti0.980O3 and Ce0.72Ti0.96O3. The A-site defect perovskites become more stable relative to oxide components as sodium contents increase. Na0.5Ce0.5TiO3 and Na0.5La0.5TiO3 could be considered as thermodynamically stable end-members in natural loparite minerals, in which these end-members are in solid solution with CaTiO3 and other components.

  • Thermodynamics and kinetics of amphotericin B self-association in aqueous solution characterized in molecular detail
    • Joanna Zielińska
    • Miłosz Wieczór
    • Tomasz Bączek
    • Marcin Gruszecki
    • Jacek Czub
    2016 Full text Scientific Reports

    Amphotericin B (AmB) is a potent but toxic drug commonly used to treat systemic mycoses. Its efficiency as a therapeutic agent depends on its ability to discriminate between mammalian and fungal cell membranes. The association of AmB monomers in an aqueous environment plays an important role in drug selectivity, as oligomers formed prior to membrane insertion – presumably dimers – are believed to act differently on fungal (ergosterol-rich) and mammalian (cholesterol-rich) membranes. In this work, we investigate the initial steps of AmB self-association by studying the structural, thermodynamic and spectral properties of AmB dimers in aqueous medium using molecular dynamics simulations. Our results show that in water, the hydrophobic aggregation of AmB monomers yields almost equiprobable populations of parallel and antiparallel dimers that rapidly interconvert into each other, and the dipole-dipole interaction between zwitterionic head groups plays a minor role in determining the drug’s tendency for self-aggregation. A simulation of circular dichroism (CD) spectra indicates that in experimental measurements, the signature CD spectrum of AmB aggregates should be attributed to higher-order oligomers rather than dimers. Finally, we suggest that oligomerization can impair the selectivity of AmB molecules for fungal membranes by increasing their hydrophobic drive for non-specific membrane insertion.

  • Thermoelectric properties of bismuth-antimony-telluride alloys obtained by reduction of oxide reagents
    • Beata Bochentyn
    • Tadeusz Miruszewski
    • Jakub Karczewski
    • Bogusław Kusz
    2016 MATERIALS CHEMISTRY AND PHYSICS

    The BieSbeTe alloys with different Bi/Sb/Te ratio were fabricated by an innovative method. For that purpose the oxide reagents were melted at high temperature, then quenched to form pellets, milled to a powder and finally reduced in hydrogen at various temperatures. Complex structures consisting of connected thin layers forming a continuous path between nano- and micrometer size grains have been obtained. The electrical conductivity, Seebeck coefficient and thermal conductivity have been determined over temperature range from 196 to þ300 C in argon atmosphere. The highest figure of merit in the whole temperature range was found for Bi0.4Sb1.6Te3 compound reduced at 400 C for 10 h in hydrogen atmosphere. At a near-room temperature the figure of merit of this compound was found to be equal to 0.7.

  • Thermo-mechanical reclaiming of ground tire rubber via extrusion at low temperature: Efficiency and limits
    • Krzysztof Formela
    • Magdalena Formela
    • Józef Haponiuk
    2016 JOURNAL OF VINYL & ADDITIVE TECHNOLOGY

    Thermomechanical reclaiming of ground tire rubber (GTR) was performed at different temperatures (60, 120, and 180°C) using a co-rotating twin-screw extruder. Obtained samples were used in styrene-butadiene rubber (SBR) blends. As reference samples, SBR compounds containing untreated GTR were used. Curing characteristics, static and dynamic mechanical properties, and morphology of the obtained blends were determined. The results show that the increase of barrel temperature during the thermomechanical reclaiming of GTR has a positive effect on the decrease of screw torque (lower machine load) and decrease of Mooney viscosity (better processing characteristics). However, mechanical properties and cross-link density of rubber revulcanizate decreased with increasing barrel temperature during the reclaiming process. SBR blends with 50 phr of reclaimed rubber showed increasing phase compatibility between SBR matrix and the reclaimed rubber, which was confirmed by mechanical properties and morphology measurements.

  • Thermoplastic elastomer filaments and their application In 3D printig
    • Agnieszka Haryńska
    • Justyna Kucińska-Lipka
    • Helena Janik
    2016 Full text Elastomery

    The paper provides an overview on the materials used in the 3D printing technology (the Polish and foreign market) with a particular focus on flexible filaments and their possible application in the industry. There are described the techniques of 3D printing and modern filaments available on the market. There is observed the increase of interest in the production of products from filaments based on thermoplastic elastomers (TPE), including the applications in the electronics and medicine, especially in tissue engineering. Ability to modify the physical and mechanical properties of thermoplastic elastomers, combined with their unique elastic and processability properties, opens new possibilities for engineers, designers and bio-engineers. The possibility to use new materials in 3D printing can contribute to faster development of research and accelerates implementation of innovative products.

  • Thin-walled cross section shape influence on steel member resistance.
    • Elżbieta Urbańska-Galewska
    • Patryk Deniziak
    • Małgorzata Gordziej-Zagórowska
    • Agnieszka Łukowicz
    2016 Full text Advances in Science and Technology Research Journal

    This work describes why trending thin-walled technology is achieving popularity in steel construction sector. A purpose of this article is to present the influence of the cold-formed element cross-section shape on an axial compression and a bending moment resistance. The authors have considered four different shapes assuming constant section area and thickness. Calculations were based on three different steel grades taking into account local, distortional and overall buckling. The results are presented in a tabular and a graphical way and clearly confirm that cross-section forming distinctly impact the cold-formed member resistance. The authors choose these cross-sections that work better in compression state and the other (those slender and high) that function more efficiently are subjected to bending.

  • Three-dimensional mapping for data collected using variable stereo baseline
    • Zdzisław Kowalczuk
    • Tomasz Merta
    2016

    The paper describes a system of 3D mapping of data collected with due regard for variable baseline. This solution constitute an extension to a VisRobot sub-system developed as a subsystem, necessary for implementing the generic idea of using mobile robots to explore an indoor static environment. This subsystem is to acquire stereo images, calculate the depth in the images and construct the sought 3D map. Stereo images are obtained at various stereo baselines, resulting in enhanced resolution of depth, especially for distant objects. The length of each baseline is obtained by currently measuring the actual location and angular pose of robotic carrier of camera. Measurement errors bring about inaccuracies in depth. Therefore, we propose an innovative procedure that combine the depth maps gained at variable baselines. The paper presents the resulting improved 3D-map visualization in terms of higher precision, considering two cases: static and cumulative localization errors.

  • Three-point bending test of sandwich beams supporting the GFRP footbridge design process - validation
    • Łukasz Pyrzowski
    • Bartosz Sobczyk
    • Wojciech Witkowski
    • Jacek Chróścielewski
    2016

    Some selected aspects concerning material and construction design issues for pedestrian footbridge made of GFRP composite materials are elaborated in this paper. The analysis is focused on validation tests, which are particularly important because of the advanced technology and materials that are used for this innovative bridge. The considered footbridge is a sandwich-type shell structure comprising of PET foam core and outer skins made of glass fibre reinforced polymer laminate. A proper connection of foam core and laminate skins is crucial, regarding its load bearing capacity. The aim of this paper is to compare experimental and Finite Element Analysis (FEA) results of sandwich beams subjected to bending loading in three point bending tests, which are afterwards used to validate the stiffness properties of the full structure.

  • THRIVING AND JOB SATISFACTION IN MULTICULTURAL ENVIRONMENTS OF MNCS
    • Malgorzata Rozkwitalska
    • Beata Basińska
    2016

    Purpose of the article The aim of the paper is to analyze the relationship between thriving and job satisfaction in multicultural environments of multinational corporations (MNCs). Methodology/methods The quantitative cross-sectional study was conducted on the sample of 128 individuals from subsidiaries of various MNCs located in Poland involved in intercultural interactions. Scientific aim The aim of this study was to examine the relationship between thriving and job satisfaction in multicultural workplaces of MNCs. It was assumed that learning is more salient than vitality in a multicultural work setting. Further, it was supposed that both components of thriving relate to overall job satisfaction and the satisfaction with intercultural interactions at work. Job tenure, job position and gender were controlled. Findings Learning was more salient than vitality in a group of specialists and managers working in multicultural work settings. After the control for job tenure, job position and gender, it was vitality not learning that was related to their overall satisfaction. In contrast, both components of thriving were related to the participants' satisfaction with intercultural interactions Conclusions It is probably the first study which quantitatively tests thriving in the model of intercultural interactions at work and includes job satisfaction as an outcome of thriving. The limitations concern a cross-sectional study and a convenient sample from different units and MNCs. The study contributes to the literature on job satisfaction in MNCs and cross-cultural management. It emphasizes the role of thriving in job satisfaction in the multicultural context. It shows that MNCs should hire employees who want to enhance their growth. In MNCs' multicultural environments such employees may thrive, which also helps them to be satisfied with their job. MNCs should also be concerned with employees' affective states to enhance their opportunities for learning.

  • Timber-frame house resistant to dynamic loads - analysis of wall panel filled with polyurethane foam
    • Marcin Szczepański
    • Wojciech Migda
    • Robert Jankowski
    2016 Full text Vibrations in Physical Systems

    The present study shows the experimentally and numerically determined response of a single timber-frame house wall panel filled with polyurethane (PU) foam under dynamic loads. The harmonic tests were conducted for the following frequencies: 0.5 Hz, 1.0 Hz, 2.0 Hz and 5.0 Hz for various values of the specified displacement. Based on the results of the comparison between the experimental tests and the numerical analyses, the numerical model has been verified to be correct. The model can be used in further analyses so as to investigate the behaviour of the whole building under dynamic loads, including seismic and paraseismic excitations. Using such a numerical model, it will be possible to evaluate the improvement in resistance against dynamic loads for the case when PU foam is used instead of mineral wool.