2014 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2014

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Determination of Pesticide Residues in Honey using the GC×GC-TOFMS Technique
- Żaneta Bargańska
- Ewa Olkowska
- Tomasz Dymerski
- Jacek Namieśnik
2014 Pełny tekst Journal of Bioprocessing & Biotechniques
In this study, a QuEChERS method and gas chromatography coupled with time-of-flight mass spectrometry (GCxGC-TOFMS) was developed for rapid extraction and simultaneous determination of 12 pesticide residues in honey. The GCxGC-TOFMS method was validated according to the SANCO guidance in terms of linearity, selectivity, reproducibility and recovery. Regarding the results, recovery rates ranged between 70-120% with relative standard deviations <20% in most cases. The method limits of quantification (LOQ) ranged between 6-26 ng/g. According to the estimated LOQ values the analytical procedure can be applied to analysis of real honey samples.
Determination of Pesticide Residues in Honeybees using Modified QUEChERS Sample Work-Up and Liquid Chromatography-Tandem Mass Spectrometry
- Żaneta Bargańska
- Marek Ślebioda
- Jacek Namieśnik
2014 Pełny tekst MOLECULES
Increasing emissions of chemical compounds to the environment, especially of pesticides, is one of factors that may explain present honeybee colony losses. In this work, an analytical method employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) was optimized for the simultaneous screening of 19 pesticides which have not been yet determined in honeybee samples from northern Poland (Pomerania). The sample preparation, based on the QuEChERS method combining salting-out liquid-liquid extraction to acetonitrile and a dispersive-SPE clean-up, was adjusted to honeybee samples by adding a small amount of hexane to eliminate beeswax. The recovery of analytes ranged from 70% to 120% with relative standard deviation ≤20%. The limits of detection were in the range of 0.91–25 ng/g. A total of 19 samples of honeybees from suspected pesticide poisoning incidents were analyzed, in which 19 different pesticides were determined.
Determination of pseudocapacitance chan ges of nickel oxide NiO electrode with use of dynamic electrochemical impedancje spectroscopy
- Paweł Ślepski
- Kazimierz Darowicki
- Karolina Andrearczyk
- Agnieszka Sierczyńska
2014 Pełny tekst International Journal of Electrochemical Science
The electrochemical capacitors (ECs) are attractive energy storage devices which can be applied in many electronic products (e.g., cameras, laptops, cell phones) or hybrid electric vehicles (HEV). The energy storage in ECs is based on capacitive (the electrical double layer charging/discharging) and pseudocapacitive (additional charge provided by faradic reaction) phenomena. Considering the electrodes exhibiting pseudocapacitance, examination of their capacitance value is usually complicated, mainly because of its dependence on applied potential. This paper presents the results of evaluating the capacitance of the nickel oxide electrode material by the analysis of the impedance spectra obtained by Dynamic Electrochemical Impedance Spectroscopy (DEIS). The proposed solution allows to acquire the detailed information about capacitance changes as a function of applied potential. Another applied technique, i.e. Atomic Force Microscopy (AFM) revealed no significant changes of electrode topography during polarization.
Determination of rectification corrections for semi gantry crane rail axes in the local 3D coordinate system
- Daria Filipiak-Kowszyk
- Waldemar Kamiński
2014 Pełny tekst REPORTS ON GEODESY AND GEOINFORMATICS
Electronic tacheometers are currently the standard instruments used in geodetic work, including also geodetic engineering measurements. The main advantage connected with this equipment is among others high accuracy of the measurement and thus high accuracy of the final determinations represented for example by the points’ coordinates. One of many applications of the tacheometers is the measurement of crane rail axes. This measurement is based on polar method and it allows to get the spatial coordinates of points in 3D local system. The standard technology of measurement of crane rail axes and development of its calculations’ results is well-known and widely presented in the subject literature. At the same time new methods of observations results evaluation are developing. Some new proposals for the development of measurement results were already presented in (Kamiński, 2013). This paper is a generalisation of the paper quoted above. The authors developed the concept which was presented there by a proposal for determining rectification corrections for semi gantry crane rail axes. To carried out the task, the parametric method with conditions on parameters was used. Moreover the practical tests on simulated measurement results were conducted. The results obtained from alignment confirmed the theoretical assumptions. Despite the fact that analyses were carried out only on the simulated data, it is already possible to say that presented method for determination of rectification corrections for crane rail axes can be used for development of the observations from real measurement.
Determination of refractive index dispersion using fiber-optic low-coherence Fabry–Perot interferometer: implementation and validation
- Katarzyna Karpienko
- Maciej Wróbel
- Małgorzata Szczerska
2014 Pełny tekst OPTICAL ENGINEERING
We present the implementation and validation of low-coherence Fabry–Perot interferometer for refractive index dispersion measurements of liquids. A measurement system has been created with the use of four superluminescent diodes with different optical parameters, a fiber-optic coupler and an optical spectrum analyzer. The Fabry–Perot interferometer cavity has been formed by the fiber-optic end and mirror surfaces mounted on a micromechanical stage. The positive result of the validation procedure has been determined through statistical analysis. All obtained results were 99.999% statistically significant and were characterized by a strong positive correlation (r>0.98). The accuracy of the measured result of implemented low-coherence Fabry–Perot interferometer sensor is from 83% to 94%, which proves that the sensor can be used in the measurement of refractive index dispersion of liquids.
DETERMINATION OF THE CITY CENTRE. STUDY FOR THE TROJMIASTO AGGLOMERATION
- Jakub Szulwic
- Artur Janowski
2014
Determination of the centre of the city or agglomeration or generally the geographic area is a task which is often undertaken as part of the promotional actions realized by local authorities or directly by inhabitants. Nowadays, especially due to the development and availability of positioning technology and satellite imaging, this job is undertaken within the framework of general didactic tasks and group projects during the study course in the field of geography, spatial planning, geographic information systems (GIS), but mainly geodesy and cartography. The task can be solved using the properties of a topological space or in Euclidean or metric space. The example given in the article was practically completed by the Scientific Hevelius Circle at the Technical University of Gdansk and it referred to the centre of the Tricity agglomeration (Trójmiasto - Gdańsk, Gdynia, Sopot in Poland).
Determination of toxic gases based on the responses of a single electrocatalytic sensor and pattern recognition techniques
- Paweł Kalinowski
- Anna Strzelczyk
- Łukasz Woźniak
- Grzegorz Jasiński
- Piotr Jasiński
2014 MEASUREMENT SCIENCE & TECHNOLOGY
A response from an electrocatalytic gas sensor contains fingerprint information about the type of gas and its concentration. As a result, a single gas sensor can be used for the determination of different gases. However, information about the type of gas and its concentration is hidden in the unique shape of the current–voltage response and it is quite difficult to explore. One of the ways to get precise information about the measured gas is to use multivariate data analysis and pattern recognition techniques. In this paper we present the results of an investigation based on a combination of the cyclic voltammetry measurement technique and chemometric analysis methods such as principal components analysis, linear discriminant analysis and the k-nearest neighbors algorithm classifier for distinguishing different types of toxic gases. The responses of the single electrocatalytic gas sensor to 20 ppm of ammonia, nitrogen dioxide, sulfur dioxide and various concentrations of hydrogen sulfide in balance with synthetic air have been measured and analyzed. The reduction of measurement points in the data set used for multivariate analysis was evaluated.
Determining pesticide contamination in honey by LC-ESI-MS/MS - Comparison of pesticide recoveries of two liquid-liquid extraction based approaches
- Marcin Kujawski
- Żaneta Bargańska
- Katarzyna Marciniak
- Ewa Miedzianowska
- Jan Kujawski
- Marek Ślebioda
- Jacek Namieśnik
2014 Pełny tekst LWT-FOOD SCIENCE AND TECHNOLOGY
Honey, a valuable food product, may be contaminated by xenobiotics during its production and/or harvest. The determination of trace levels of contaminants in a complex matrix like honey still presents a challenge to analytical chemists. The aim of this work was to assess and compare the extraction efficiencies of 30 pesticide residues (acaricides, insecticides, herbicides, fungicides), belonging to over 15 different chemical classes. Two common extraction approaches were applied e the increasingly popular QuEChERS method and extraction on a diatomaceous earth support. Both are used for pesticide determinations in fruits and vegetables, and with some adjustments they can be used for honey samples. In order to assess whether the differences in recoveries between the two investigated methods were statistically significant, the F-Snedecor and T-test were employed. The recoveries ranged from 34 to 96%, and in the case of 4 pesticides the differences in the values were statistically significant. Both methods showed good linearity (R2 > 0.991), and the extraction efficiencies enabled method quantification limits well below EU-recommended Maximum Residue Levels to be achieved for the investigated pesticides.
Detrminanty jakości promocji usług turystycznych na przykładzie ofert wystawienniczych
- Grzegorz Zieliński
- Małgorzata Dąbek
2014
W niniejszym rozdziale zaprezentowano kluczowe determinanty jakości promocji usług turystycznych w przypadku wykorzystania stoisk wystawienniczych. Wnioski zostały wyprowadzone na podstawie badania praeprowadzonego w grupie 93 wystawców związanych z branża turystyczną.
Detrminanty jakości usług edukacyjnych
- Małgorzata Wiśniewska
- Małgorzata Szymańska-Brałkowska
- Grzegorz Zieliński
2014 Pełny tekst PRACE NAUKOWE UNIWERSYTETU EKONOMICZNEGO WE WROCŁAWIU
W nieniejszym opracowaniu autorzy podjęli próbę identyfikacji kluczowych determinant jakości usłuigi edukacyjnej z punktu widzenia klasycznego modelu zarządzania operacyjnego. Wyróżniono determinanty obszaru wejścia, działań operacyjnych, jak i wyjścia, ułatwiające dalsze badania w kierunku bardziej szczególowej oceny jakości usługi edukacyjnej. W trakcie analizy zwrócono uwagę na obszar zasobów ludzkich, w tym przede wszystkim na determinanty określające pracowników akademickich na oczekiwania studentów wobec usługi edukacyjnej, na programy studiów, infrastrukturę i środki finansowe, jak również na działania operacyjne związane z procesem dostarczania usługi oraz na jej efekty.
Developing a methodology for model tests of floating platforms in a towing tank of low depth
- Czesław Dymarski
- Paweł Dymarski
2014
The paper presents two ways to mooring model of semi-submersible platform for research in the small depth towing pool. The tested model was made in the likeness of 1:100 Thunder Horse platform moored in the Gulf of Mexico at a depth of 1,920 m. Its mooring system consisted of 16 semi-taut mooring lines (chain-wire-chain) spaced Star-shape and attached at the bottom to the suction piles. The tests were performed in the towing pool of the Gdansk University of Technology (GUT). The depth of the pool equal 1.5 m is about 13.5 times less than that required for a typical model tests . This required the development and use of non-standard methods of mooring the model adapted to the technical conditions existing in the laboratory and material possibilities. The paper presents two mooring systems of the model and calculated the characteristics of static displacement of the model as a function of the external horizontal load . These characteristics were scaled to the natural conditions and compared with the calculated characteristics of the reference platform .
Developing competences for cooperation in international teams - tools and methods
- Beata Krawczyk-Bryłka
- Katarzyna Stankiewicz
2014
The article presents the training methods that can be used to develop intercultural competences which are extremely important while working in intercultural teams. The mentioned methods like: case-studies, collaborating, role-play simulations, team working, video presentations and others are presented on the basis of authors’ experiences while teaching the international groups of students at Faculty of Management and Economics at GUT. There are also participants’ opinion presented to evaluate the used teaching methods and learning outcomes.
Developing competences of IT project managers using simulation games
- Artur Ziółkowski
- Kamil Ziółkowski
2014
Project Management is a domain in which methodological approach is developing very rapidly. Project managers are required to present knowledge of the various methods of project management and apply them to the management of specific projects. It means that project managers must constantly develop their competence, mainly based on good practices from different formal methods of project management. The purpose of this article is to demonstrate the possibilities of education of project managers through the use of simulation games. The article presents some good practices related to the development of managerial skills project managers using simulation games. Therefore, on the beginning of the article, author presents some examples of simulation games related to popular methods of project management. One of the simulations concerns the classical approach - RUP, second relates to the agile approach. The second part of the article includes a set of competencies of project managers and then shows how these competencies can be enhanced by participation in such simulation games. At the end author presents a set of observations and experiences based on few project simulations carried on over several years.
Development and Validation of SPE-HPLC-MS/MS Method for Determining Cyclophosphamide in Surface Waters
- Radosław Czernych
- Jan Halkiewicz
- Agata Kot-Wasik
- Jacek Namieśnik
2014 Pełny tekst POLISH JOURNAL OF ENVIRONMENTAL STUDIES
A rapid and selective method for trace amounts determination of cyclophosphamide in surface water samples has been developed. A solid phase extraction SPE method for extraction and clean-up procedure has been optimized for determination by reversed-phase high-performance liquid chromatography with tandem mass spectrometry. The analyses proceed in the positive ion mode by means of the electrospray ionization method (ESI). Clean up was accomplished using a polimeric surface modified styrene – divinylobenzene SPE column. The final method was validated according to international chemical harmonization (ICH) standards. High selectivity of assay procedure was obtained by choosing optimal columns (most columns contained a bed modified with C18 groups but varied in the amount of bed: 50-500 mg, and grain size: 33-80 μm) and setting separation conditions, such as flow rate during sorption (2 and 6 mL/min), sorbent type, pH of the sample (samples at pH 3 and 7 were examined), solvent strength during desorption (methanol and dichloromethane), time of evaporation (10, 20, and 30 minutes), type of solvent used for injection (HPLC) (water, methanol and methanol-water mixture, 1:1, v/v), matrix effect (tap water and river water), and time “sample preparationanalysis” on recovery (3, 6, and 9 days). After optimization of sample preparation procedure and analytical conditions environmental water samples were collected from five sampling sites situated in Gdańsk (Pomerania, Poland) and its outskirts and subjected to validated methodology. In four samples cyclophosphamide has been quantified.
Development of Local IDF-formula Using Controlled Random Search Method for Global Optimization
- Katarzyna Weinerowska-Bords
2014 Pełny tekst Acta Geophysica
The aim of the study is to present the effective and relatively simple empirical approach to rainfall Intensity-Duration-Frequency-formulas development, based on Controlled Random Search (CRS) for global optimization. The approach is mainly dedicated to the cases in which the commonly used IDF-relationships do not provide satisfactory fit between simulations and observations, and more complex formulas with higher number of parameters are advisable. Precipitation data from Gdansk gauge station were analyzed as the example, with use of peak-over-threshold method and Chomicz scale for rainfall intensity. General forms of the IDF-function were chosen and the parameter calibration with use of CRS algorithm was developed. The compliance of the obtained IDF-formulas with precipitation data and the efficiency of the algorithm were analyzed. The study confirmed the proposed empirical approach may be an interesting alternative for probabilistic ones, especially when IDF-relationship has more complex form and precipitation data do not match ‘typical’ hydrological distributions.
Developments in Green Chromatography
- Marek Tobiszewski
- Jacek Namieśnik
2014 LC GC EUROPE
Green analytical chemistry is a widely recognized concept that has led to the development of new analytical methods with reduced environmental impact and minimized analyst occupational exposure. Achievements include the development of microextraction, ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE) techniques. Research towards greener separation processes focuses on the elimination of toxic solvents in liquid chromatography (LC) and the reduction of separation time. The recent developments in the labelling and categorization of analytical procedures are also presented. The National Environmental Methods Index (NEMI), Eco-Scale, and grouping with multivariate statistics are discussed together with their advantages and limitations. This article presents the most recent progress in the development of greener sample preparation and chromatographic separation techniques.
Developments in the synthesis and biological activity of Glycyl-L-Histydyl-L-Lysine derivatives
- Monika Kukowska
- Krystyna Dzierzbicka
2014 CURRENT MEDICINAL CHEMISTRY
We emphasize on the methods of the synthesis described in the literature and present the aspects of Gly-His-Lys structure modifications that played a key role in scientific research.
Diagnostics of bolted lap joint using guided wave propagation
- Rafał Kędra
- Magdalena Rucka
2014 Pełny tekst Diagnostyka
The paper presents numerical and experimental analyses of elastic waves propagation in a bolted lap joint. In experimental investigations condition assessment of the joint was performed with the use of symmetric waves excited by a piezoactuator. Numerical calculations were conducted in commercial finite element method software Abaqus. The influence of number of bolts and the value of the initial stress on recorded signals was examined. The study showed the possibility of using elastic waves in the context of diagnostics of bolted joints.
Diagnostics of the tram track shape with the use of the global positioning satellite systems (GPS/Glonass) measurements with a 20 Hz frequency sampling
- Cezary Specht
- Władysław Koc
- Leszek Smolarek
- Andrzej Grządziela
- Jacek Szmagliński
- Mariusz Specht
2014 Pełny tekst Journal of Vibroengineering
Satellite geodetic measurements used in the diagnosis of railway tracks require professional receivers and a very high frequency rate of data processing. It stems from a significant speed (10 km/h) kinematic measurements carried out during the passage of a measuring platform. The survey results (positions) of deformed railroad track have waveforms nature requiring additional processing methods and approximations. Due to the announcement in 2011 of the operating status for the Russian Global Navigation System (Glonass) and launching a commercial geodetic satellite network SmartNet in northern Poland (2012) created for the first time a possibility of carrying out measurements using two satellite systems (GPS/GLONASS) which significantly increase the accuracy of measurements on a rail. A paper presents a possibility of using two-system satellite receivers to measure the deformation of the tram track on the example of the measurement line in Gdansk (October 2013). The studies used rarely encountered in geodesy a very high position frequency rate (20 Hz), which entails the use of wave processing methods.
Diagnostics of thermal processes in antenna systems of broadcast stations
- Mikołaj Bartłomiejczyk
- Milan Simko
- Milan Chupac
- Stefan Hamacek
2014 Pełny tekst Przegląd Elektrotechniczny
Diagnostics is an important element associated with the operation of a radio antenna systems, allowing earlier detection of potential damage. Thermography is one of the diagnostic tools, which allows for non-invasive assessment of technical condition. It brings together both financial savings associated with the removal of the damage and the potential effects caused by it. The article presents an example of using a thermal imaging technique in fault location antenna systems