2020 - Repozytorium publikacji - Politechnika Gdańska

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Adaptive Algorithm of a Tap-Changer Controller of the Power Transformer Supplying the Radial Network Reducing the Risk of Voltage Collapse
- Robert Małkowski
- Michał Izdebski
- Piotr Miller
2020 Pełny tekst ENERGIES
he development of renewable energy, including wind farms, photovoltaic farms as well as prosumer installations, and the development of electromobility pose new challenges for network operators. The results of these changes are, among others, the change of network load profiles and load flows determining greater volatility of voltages. Most of the proposed solutions do not assume a change of the transformer regulator algorithm. The possibilities of improving the quality of regulation, which can be found in the literature, most often include various methods of coordination of the operation of the transformer regulator with various devices operating in the Medium-Voltage (MV) network. This coordination can be decentralized or centralized. Unfortunately, the proposed solutions often require costly technical resources and/or large amounts of real-time data monitoring. The goal of the authors was to create an algorithm that extends the functionality of typical transformer control algorithms. The proposed solution allows for reducing the risk of voltage collapse. The performance of the proposed algorithm was validated using multivariate computer simulations and tests with the use of a physical model of the distribution network. The DIgSILENT PowerFactory environment was used to develop the simulation model of the proposed algorithm. Then, tests were conducted on real devices installed in the LINTEˆ2 Laboratory at the Gdańsk University of Technology, Poland. Selected test results are included in this paper. All results have shown that the proposed algorithm makes it possible to increase the reserve of the voltage stability of the node, in which it is applied, thus mitigating the risk of a voltage collapse occurring. The proposed algorithm does not require complex and costly technical solutions. Owing to its simplicity, it has a high potential for practical application, as confirmed by the real-time control experiment in the laboratory.
Adaptive Positioning Systems Based on Multiple Wireless Interfaces for Industrial IoT in Harsh Manufacturing Environments
- Jordi Mongay Batalla
- Constandinos X. Mavromoustakis
- George Mastorakis
- Neal Xiong, Naixue
- Józef Woźniak
2020 Pełny tekst IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
As the industrial sector is becoming ever more flexible in order to improve productivity, legacy interfaces for industrial applications must evolve to enhance efficiency and must adapt to achieve higher elasticity and reliability in harsh manufacturing environments. The localization of machines, sensors and workers inside the industrial premises is one of such interfaces used by many applications. Current localization-based systems are unable to deal with highly variable conditions, meaning that the solutions working well in stationary systems suffer from considerable difficulties in harsh environments, such as factories. As a result, the precision of localization techniques is not satisfactory in most industrial applications. This paper fills in the existing gap between static approaches and dynamic indoor positioning systems, by presenting a solution adapting the system to highly changeable conditions. The proposed solution makes use of a Machine Learning-based feedback loop that learns the variability of the environment. This feedback makes continuous fingerprint calibration feasible even in the presence of different machines and Industrial Internet of Things sensors that introduce variations to the electromagnetic environment. This paper also presents a comprehensive indoor positioning system solution that reduces complexity of hardware, meaning that a multi-standard-transceiver infrastructure may be adopted with reduced capital and operational expenditures.We have developed the system from scratch and have conducted an extensive range of testbed experiments showing that the multi-technology transceiver feature is capable of increasing positioning accuracy, as well as of introducing permanent fingerprints calibration at harsh industrial premises.
Adaptive traffic optimization using Variable Speed Limits; Adaptacyjna optymalizacja ruchu drogowego przy pomocy zmiennych ograniczeń prędkości
- Paweł Gora
2020
Variable speed limits (VSL) is an intelligent transportation system (ITS) solution for traffic management. The speed limits can be changed dynamically in order to adapt to traffic, weather, or road surface conditions. This paper presents an approach for such an adaptive traffic control where the primary goal is to ensure traffic safety and efficiency of the traffic control system (fast response to dynamically changing traffic, weather and road surface conditions). In the case of the straight roads, the method takes into account road surface conditions, visibility, and traffic density. In the case of bends, it takes into account the curvature and the road adhesion but also tries to harmonize speed before and after the bend. The experiments on a selected road segment conducted using a simulation framework SUMO with various traffic flows and weather conditions showed that the method works fine and is able to reduce the speed of cars to safe values depending on the road surface conditions, visibility, and traffic.
Adsorption behavior and corrosion inhibitive characteristics of newly synthesized cyano-benzylidene xanthenes on copper/sodium hydroxide interface: Electrochemical, X-ray photoelectron spectroscopy and theoretical studies
- Mohamed Khalifa
- Islam Azab El
- Adil Gobouri
- Gaber Mersal
- Sarah Alharthi
- Murat Saracoglu
- Fatma Kandemirli
- Jacek Ryl
- Mohammed Amin
2020 Pełny tekst JOURNAL OF COLLOID AND INTERFACE SCIENCE
Elegant process for synthesis of 3-(7H-dibenzo[c,h]xanthen-7-yl)benzaldehyde (3), as new starting material to create a set of novel xanthene analogues, 2-(3-(7H-dibenzo[c,h]xanthen-7-yl)benzylidene)malononitrile (4), 3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylic acid (5), and Ethyl-3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylate (6), was achieved starting with available materials under mild conditions. Various concentrations (ca. 0.1–1.0 mM) of the synthesized cyano-benzylidene xanthene derivatives, namely compounds 3–6, were tested as inhibitors to control copper corrosion in alkaline solutions employing polarization and electrochemical impedance spectroscopy (EIS) measurements. Results revealed that the four studied xanthenes derivatives served as efficient (mixed-type) inhibitors. The inhibition efficiency increased with increase in inhibitor concentration.The inhibition performance of studied compounds varied according to their chemical structures. The best inhibitor, compound (5), achieved a maximum inhibition efficiency of 98.7% (calculated from corrosion current densities) and ~ 95% (estimated from charge-transfer resistance values) at a concentration of 1.0 mM. The morphology of the corroded and inhibited copper surfaces was studied by scanning electron microscopy (SEM). The adsorption of the inhibitor molecules was confirmed by high-resolution X-ray photoelectron spectroscopy (XPS) profiles. XPS data were used to compare the inhibition efficiencies exhibited by studied compounds. The oxidation rate of the Cu surface was found to be frivolous, referring to high inhibition efficiency, only in the presence of inhibitor (5), and Cu0 share is 87% of all copper components. The shares of Cu0 were significantly reduced to 43%, 26% and 20% for inhibitors (3), (4) and (6), respectively. These findings go parallel with the results obtained from electrochemical measurements. The quantum-chemical calculations of the investigated molecules were performed to support electrochemical findings, and their correlations with the inhibition efficiency of the synthesized compounds were discussed.
Advanced Lithium-Ion Battery Model for Power System Performance Analysis
- Szymon Potrykus
- Filip Kutt
- Janusz Nieznański
- Francisco Jesús Fernández Morales
2020 Pełny tekst ENERGIES
The paper describes a novel approach in battery storage system modelling. Different types of lithium-ion batteries exhibit differences in performance due to the battery anode and cathode materials being the determining factors in the storage system performance. Because of this, the influence of model parameters on the model accuracy can be different for different battery types. These models are used in battery management system development for increasing the accuracy of SoC and SoH estimation. The model proposed in this work is based on Tremblay model of the lithium-ion battery. The novelty of the model lies in the approach used for parameter estimation as a function of battery physical properties. To make the model perform more accurately, the diffusion resistance dependency on the battery current and the Peukert effect were also included in the model. The proposed battery model was validated using laboratory measurements with a LG JP 1.5 lithium-ion battery. Additionally, the proposed model incorporates the influence of the battery charge and discharge current level on battery performance.
Advanced operating methods
- Janusz Smulko
2020
Selected operating methods of resistive gas sensors were presented. The methods utilize flicker noise (1/f noise), which gives additional information about ambient gas when compared with the recorded changes of DC resistance only. Methods of flicker noise measurements were outlined. Recently developed prototype gas sensors comprising golden nanoparticle functionalized with organic ligands can generate intense flicker noise induced by volatile organic compounds. These phenomena can be utilized in inexpensive and portable measurement setups. Popular gas sensing materials (e.g., WO3 and TiO2) exhibit a photocatalytic effect, which can be employed to improve the selectivity and sensitivity of gas detection. Recently proposed commercial resistive gas sensors are of much smaller dimensions and energy consumption. These new series of gas sensors can be used in the proposed methods when limited energy consumption is a crucial factor. An overview of emerging new applications of low-cost resistive gas sensors is given. Bootlegs of the technology arising were identified and compared with the applications presented.
Advanced Turbine Cycles with Organic Media
- Marian Piwowarski
- Krzysztof Kosowski
2020 Pełny tekst ENERGIES
Organic Rankine Cycle (ORC) power plants have become very popular and have found their applications in systems with renewable sources of energy. So far their overall efficiencies are not very impressive and only for the upper temperature of about 300 °C do they exceed 20%. A drawback of these cycles is the limitation of the cycle upper temperature due to the heat exchanger technology and the materials used. However, it is possible to overcome these difficulties by certain modifications of the thermodynamic cycles, a proper choice of the working medium and the optimization of cycle parameters. In the paper the problems of choosing the working medium and the question of higher temperature at the turbine inlet have been discussed. Different modifications of the schemas of the thermodynamic cycles have also been taken into account. The variants of power plants with regenerators, reheaters and heat exchangers have been considered. The proposed increase in temperature (in some cases up to 600 °C or higher) and innovative modifications of the thermodynamic cycles allow to obtain the power plant efficiency of above 50%. The modified cycles have been described in detail in the paper. The proposed cycles equipped with regenerators and reheaters can have the efficiency even slightly higher than classical steam turbine plants with a reheater and regenerators. Appropriate cycle and turbine calculations have been performed for the micro power plants of turbine output in the range of 10 kW–300 kW (up to several MW in some cases). The best arrangements achieved very high values of the overall cycle efficiency.
Advancing the evidence base for public policies impacting on dietary behaviour, physical activity and sedentary behaviour in Europe: The Policy Evaluation Network promoting a multidisciplinary approach
- Jeroen Lakerveld
- Catherine Woods
- Antje Hebestreit
- Hermann Brenner
- Marion Flechtner-Mors
- Janas M. Harrington
- Carlijn B.M. Kamphuis
- Michael Laxy
- Aleksandra Luszczynska
- Mario Mazzocchi
- Celine Murrin
- Maartje Poelman
- Ingrid Steenhuis
- Gun Roos
- Jürgen M. Steinacker
- Christian C. Stock
- Frank van Lenthe
- Hajo Zeeb
- Joanna Żukowska
- Wolfgang Ahrens
2020 Pełny tekst FOOD POLICY
Non-communicable diseases (NCDs) are the leading cause of global mortality. As the social and economic costs of NCDs have escalated, action is needed to tackle important causes of many NCD’s: low physical activity levels and unhealthy dietary behaviours. As these behaviours are driven by upstream factors, successful policy interventions are required that encourage healthy dietary behaviours, improve physical activity levels and reduce sedentary behaviours of entire populations. However, to date, no systematic research on the implementation and evaluation of policy interventions related to these health behaviours has been conducted across Europe. Consequently, no information on the merit, gaps, worth or utility of cross-European policy interventions is available, and no guidance or recommendations on how to enhance this knowledge across European countries exists. As part of the Joint Programming Initiative “A Healthy Diet for a Healthy Life” (JPI HDHL), 28 research institutes from seven European countries and New Zealand have combined their expertise to form the Policy Evaluation Network (PEN). PEN’s aim is to advance tools to identify, evaluate, implement and benchmark policies designed to directly or indirectly target dietary behaviours, physical activity, and sedentary behaviour in Europe, as well as to understand how these policies increase or decrease health inequalities. Using well-defined evaluation principles and methods, PEN will examine the content, implementation and impact of policies addressing dietary behaviour, physical activity levels and sedentary behaviour across Europe. It will realise the first steps in a bespoke health policy monitoring and surveillance system for Europe, and refine our knowledge of appropriate research designs and methods for the quantification of policy impact. It will contribute to our understanding of how to achieve successful transnational policy implementation and monitoring of these policies in different cultural, demographic or socioeconomic settings. PEN will consider equity and diversity aspects to ensure that policy actions are inclusive and culturally sensitive. Finally, based on three policy cases, PEN will illustrate how best to evaluate the implementation and impact of such policies in order to yield healthy diets and activity patterns that result in healthier lives for all European citizens.
Advantageous conditions of saccharification of lignocellulosic biomass for biofuels generation via fermentation processes
- Karolina Kucharska
- Edyta Słupek
- Hubert Cieśliński
- Marian Kamiński
2020 Pełny tekst CHEMICAL PAPERS
Processing of lignocellulosic biomass includes four major unit operations: pre-treatment, hydrolysis, fermentation and product purifcation prior to biofuel generation via anaerobic digestion. The microorganisms involved in the fermentation metabolize only simple molecules, i.e., monosugars which can be obtained by carrying out the degradation of complex polymers, the main component of lignocellulosic biomass. The object of this paper was to evaluate the saccharifcation conditions and identify the process parameters that should be applied to improve the saccharifcation efciency of lignocellulosic biomass, defned as the simple sugars concentration, which was considered as a crucial parameter for hydrogen generation via dark fermentation. Drawing global conclusions about the occurring changes in the biomass requires learning about the nature of the biomass structure and composition at diferent stages of the process. Therefore, techniques for analysis, as FTIR, HPLC and SEM were applied. The experiment was planned employing Box–Behnken design. The advantageous operating conditions and the composition of saccharifcation enzymatic cocktail were identifed and their values occurred similar in the applied border conditions for all tested biomass types. Analysis of the intermediate solid and liquid streams generated during the pre-treatment procedure revealed several structural and compositional changes in the biomass.
AEGIS – Mobile Device for Generating Electromagnetic Curtain for Special Applications and Countering the Threats of RCIED
- Piotr Rajchowski
- Krzysztof Cwalina
- Jarosław Magiera
- Alicja Olejniczak
- Paweł Kosz
- Agnieszka Czapiewska
- Robert Burczyk
- Krzysztof Kowalewski
- Jarosław Sadowski
- Sławomir Ambroziak
2020 Pełny tekst International Journal of Electronics and Telecommunications
In the article the assumptions, design and realization of the technological demonstrator of a mobile device for generating an electromagnetic curtain (with a cryptonym AEGIS) were presented, both in the area of hardware and software. The device is designed to block the radio communication systems by which it is possible to detonate the Radio Controlled Improvised Explosive Devices (RCIEDs). The preliminary laboratory tests of the demonstrator for generating the jamming signal, that were presented in the paper, aimed at assessing the correctness of the device operation and verification of generated signal parameters. On the basis of the obtained results, the ability to jam the cellular systems as well as other radio devices operating in the frequency band from 400 MHz to 2700 MHz was assessed.
Aerodynamic Shape Optimization for Delaying Dynamic Stall of Airfoils by Regression Kriging
- Vishal Raul
- Leifur Leifsson
- Sławomir Kozieł
2020
The phenomenon of dynamic stall produce adverse aerodynamic loading which can adversely affect the structural strength and life of aerodynamic systems. Aerodynamic shape optimization (ASO) provides an effective approach for delaying and mitigating dynamic stall characteristics without the addition of auxiliary system. ASO, however, requires multiple evaluations time-consuming computational fluid dynamics models. Metamodel-based optimization (MBO) provides an efficient approach to alleviate the computational burden. In this study, the MBO approach is utilized for the mitigation of dynamic stall characteristics while delaying dynamic stall angle of the flow past wind turbine airfoils. The regression Kriging metamodeling technique is used to approximate the objective and constrained functions. The airfoil shape design variables are described with six PARSEC parameters. A total of 60 initial samples are used to construct the metamodel, which is further refined with 20 infill points using expected improvement. The metamodel is validated with the normalized root mean square error based on 20 test data samples. The refined metamodel is used to search for the optimal design using a multi-start gradient-based method. The results show that an optimal design with a 3∘ delay in dynamic stall angle as well a reduction in the severity of pitching moment coefficients can be obtained.
Agile Requirements Prioritization in Practice: Results of an Industrial Survey
- Aleksander Jarzębowicz
- Natalia Sitko
2020 Pełny tekst Procedia Computer Science
Agile software development stresses the importance of providing the customer with a product of a maximized business value. To achieve that, requirements prioritization is used. Agile development methods like Scrum define guidelines for prioritization, however practitioners do not necessarily have to follow them. Our goal was to investigate the industry practice related to requirements prioritization process, including its timing, participants, criteria used and prioritization techniques applied. We designed an on-line questionnaire (based on literature review) and conducted a survey involving practitioners from Polish IT industry. We received 69 valid responses indicating requirements prioritization practices in industrial Agile projects. We found out that despite the fact that business value is the most common criterion used to prioritize requirements, other criteria like complexity, stability and mutual interdependencies are considered as well. Other findings indicate that consideration of such multiple criteria requires different viewpoints, thus making requirements prioritization a process that has to involve many participants of different roles and competencies.
AGREE—Analytical GREEnness Metric Approach and Software
- Francisco Pena-Pereira
- Wojciech Wojnowski
- Marek Tobiszewski
2020 Pełny tekst ANALYTICAL CHEMISTRY
Green analytical chemistry focuses on making analytical procedures more environmentally benign and safer to humans. The amounts and toxicity of reagents, generated waste, energy requirements, the number of procedural steps, miniaturization, and automation are just a few of the multitude of criteria considered when assessing an analytical methodology’s greenness. The use of greenness assessment criteria requires dedicated tools. We propose the Analytical GREEnness calculator, a comprehensive, flexible, and straightforward assessment approach that provides an easily interpretable and informative result. The assessment criteria are taken from the 12 principles of green analytical chemistry (SIGNIFICANCE) and are transformed into a unified 0−1 scale. The final score is calculated based on the SIGNIFICANCE principles. The result is a pictogram indicating the final score, performance of the analytical procedure in each criterion, and weights assigned by the user. Freely available software makes the assessment procedure straightforward. It is open-source and downloadable from https://mostwiedzy.pl/AGREE.
Air-cooled photovoltaic roof tile as an example of the BIPVT system – An experimental study on the energy and exergy performance
- Jan Wajs
- Aleksandra Gołąbek
- Roksana Bochniak
- Dariusz Mikielewicz
2020 Pełny tekst ENERGY
The air-cooled photovoltaic tile is a subject of presented investigations, which focused on improving the overall system efficiency of PV tiles with heat recovery. The operational efficiency of a PV roof tile, together with the construction optimising the air cooling efficiency, were the main points of plans realized at this research stage. The article describes the experimental research consisting of the assessment of electrical, thermal, and total efficiency, as well as exergy efficiency and parameters of a commercial photovoltaic (PV) roof tile, which back wall was cooled by flowing air. An influence of various cooling duct depths and various volumetric flow rates on the system operation was analysed. During the tests, a solar light simulator and a radial fan, providing the assumed volumetric flow rate of cooling air were used. It has been proven that the depth of the cooling duct and the air volumetric flow rate have a crucial impact on the obtained results. Air cooling the back wall of the PV roof tile, lowered the average surface temperature by a maximum of 6.3 K, while the temperature difference, between the surface next to the cooling air inlet and the surface next to its outlet, was a maximum of 23.4 K. Both values were obtained for air cooling with a volumetric flow rate equal to 4 m3/h and a channel depth of 25 mm, with a solar irradiance of 900 W/m2. The overall efficiency was calculated as a sum of the electrical an thermal efficiencies. Its maximal obtained value was about 32%, wherein the highest thermal efficiency was at the level of 27%. An exergy analysis was performed and the exergy efficiency between 5.08 % and 9.94 % was determined. These results are promising for future utilization of the system consisted of the PV roof tiles together with the cooling ducts.
Aktualność "Sporu o istnienie świata" Romana Ingardena w świetle współczesnych mu stanowisk filozoficznych
- Andrzej Lisak
2020 Pełny tekst Przegląd Filozoficzny Nowa Seria
Paradoksalnie Ingarden nie jest w stanie wykazać, że świat realny istnieje w pewnym zasadniczym sensie „istnienia”, bo przyjmuje taki sam jak Husserl egologiczny, przeżyciowy model czystej świadomości i sam podążając za Husserlem przyjmuje istnienie dwóch dziedzin przedmiotów indywidualnych: dziedzinę czystej świadomości (rozumianej po husserlowsku jako strumień przeżyć) i dziedzinę świata realnego za punkt wyjścia swoich rozważań. Świadomość pojmowana jest tutaj jako zbiór aktów, a nie treści. Świadomość jest jednak(co dobrze pokazał w neokantyźmie Natorp, a w obrębie fenomenologii Sartre) pierwotnością, w której konstytuuje się z jednej strony świat a drugiej strony realny podmiot, sama więc nie może być utożsamiana z podmiotem Sama niczego nie konstytuuje, ale jest miejscem, w którym widzimy samą konstytucję Świadomość tak pojęta nie zawiera przeżycia świata, ale jest bezpośrednio przy bycie. To, że posiadamy przeżycie świata jest dopiero wtórnie przez już ukonstytuowany w pierwotnej świadomości podmiot domniemane. Dzielone wspólnie z Husserlem kartezjańskie założenia w połączeniu z przejętym z empiryzmu brytyjskiego modelem poznania: „treść wrażeniowa – jej intencjonalne ujęcie” oraz w połączeniu z tym, co określam „metafizyką ciała stałego” są powodem fiaska projektu Ingardena. Odsłaniane są zarazem te momenty filozofii Ingardena, które rzeczywiście prowadzą w stronę realizmu.
Aktywna Termografia Dynamiczna - przetwarzanie serii obrazów w diagnostyce medycznej
- Mariusz Kaczmarek
- Antoni Nowakowski
2020
Aktywna termografia dynamiczna (ATD) jest metodą obrazowania zmian temperatury na powierzchni badanego obiektu w czasie jako odpowiedź na zastosowane pobudzenie zewnętrzne (ogrzewanie lub chłodzenie). Celem badania jest określenie właściwości obiektu w czasie trwania termicznych procesów przejściowych, takich jak grzanie lub chłodzenie. Obiekt badany jest pobudzany sygnałem cieplnym (zewnętrznie) lub farmakologicznie (wewnętrznie). Formą odpowiedzi obiektu na to pobudzenie jest zmiana temperatury (wzrost lub spadek), a szybkość zmian temperatury zawiera informację o wartościach pojemności cieplnej (Cp) i przewodności cieplnej (ke), charakteryzujących strukturę badanego obiektu. Dla organizmów żywych należy jednak uwzględniać transport ciepła przez krew, a także procesy generacji ciepła w cyklu metabolicznym. Mechanizmy te ujęte są w modelu zaproponowanym w latach 40-tych XX wieku przez Pennesa. Jest to tzw. równanie biologicznego przepływu ciepła. Zdefiniowanych dodatkowych czynników biologicznych nie ma w przypadku analizy przejściowych procesów cieplnych w materiałach sztucznych-przemysłowych. ATD może stanowić w badaniach medycznych nową jakość, jako że pozwala na określenie właściwości termicznych tkanek będących często pochodnymi ukrwienia i procesów metabolicznych. Stanowi też uzupełnienie dla termografii statycznej, która jest bardziej podatna na działanie czynników zewnętrznych. W dotychczasowych aplikacjach aktywnej termografii dynamicznej w medycynie można wyróżnić dwa kierunki. Pierwszy, związany jest z badaniem zmian homeostazy badanej tkanki, na którą zadziałał bodziec np. w kardiochirurgii przy badaniu drożności naczyń. Drugi kierunek koncentruje się na badaniu powierzchni tkanki i różnicowaniu obszarów patologicznych od prawidłowych, które charakteryzują się odmiennymi parametrami termicznymi takimi jak przewodność cieplna i pojemność cieplna. Dla termografii z wymuszeniem rozkład temperatury będzie się zmieniał na kolejnych termogramach wraz z trwaniem bodźca termicznego, a po jego ustaniu obserwowana na powierzchni temperatura będzie dążyła do stanu równowagi termicznej, a rozkład temperatury również będzie się zmieniał, aż do osiągnięcia stanu ustalonego. Te procesy dążenia do osiągnięcia stanu ustalonego można scharakteryzować tzw. zastępczym modelem termicznym (ZMT), najczęściej pewną postacią równania matematycznego ze współczynnikami, których wartości wyznaczone zostaną w procedurze dopasowania do danych pomiarowych (PDD).
Aktywność biologiczna koniugatów nanonośników molekularnych z inhibitorami enzymatycznymi
- Dorota Martynow
2020 Pełny tekst
Przedmiotem badań były cztery grupy koniugatów nanonośników molekularnych z inhibitorami enzymatycznymi o potencjalnym działaniu przeciwgrzybowym. Pierwszą z tych grup tworzyły koniugaty peptydów penetrujących z inhibitorem gyrazy ciprofloksacyną lub z cząsteczką kwasu N3-(4-metoksyfumaroilo)-L-2,3-diaminopropanowego (FMDP), inhibitorem syntazy GlcN-6-P. W dwóch kolejnych grupach, cząsteczki FMDP oraz cispentacyny, inhibitora syntetazy Ile-tRNAIle połączone były z nanonośnikami lipidowymi lub tzw. parasolami molekularnymi. W niektórych z tych koniugatów występował ,jako dodatkowy składnik mający zapewnić efektywne uwalnianie inhibitora, tzw. „trimethyl lock‖. Ponadto, zbadano także wpływ skoniugowania parasoli molekularnych z antybiotykami przeciwgrzybowymi z grupy makrolidów polienowych na ich selektywną toksyczność in vitro w układzie komórki grzybowe: komórki ssacze. Wykonano szereg badań dotyczących nośników związków aktywnych o działaniu przeciwgrzybowym. Wykazano, że ich modyfikacja za pomocą nośników może doprowadzić do polepszenia aktywności przeciwgrzybowej, polepszenia zdolności transportowych oraz zmniejszenia właściwości hemolitycznych i cytotoksycznych. Wykonane badania mogą służyć jako silne podstawy do zaprojektowania skutecznego i nietoksycznego układu nośnik-lek o działaniu przeciwgrzybowym.
AKUSTYCZNY ASPEKT ZASTOSOWANIA BLACHY KORTENOWEJ W EUROPEJSKIM CENTRUM SOLIDARNOŚCI W GDAŃSKU
- Andrzej Kulowski
- Wojciech Targowski
2020
Artykuł opisuje użycie blachy kortenowej jako dominującego materiału wykończeniowego na elewacjach i we wnętrzach budynku o przesłaniu symbolicznym. Przedstawiono architektoniczne przesłanki, uzasadniające jednorodność zastosowanego materiału. Na tym tle omówiono wpływ blachy kortenowej na akusty-kę pomieszczeń, wraz z podaniem kroków zaradczych redukujących nadmierną pogłosowość i zwiększających stopień rozproszenia dźwięku. Pozytywnym sprawdzianem dla warunków akustycznych uzyskanych w największym pomieszczeniu ECS jest zaprezentowanie w nim dużego dzieła z dziedziny muzyki klasycznej.
"Alians znaków"
- Dominika Krechowicz
2020
Wystawa "Koncepcja obrazu - Twórcy Galerii Koło". Prezentacja nowej pracy z cyklu "Alians znaków" na wystawie w Centrum Sztuki Współczesnej Łaźnia 2, ul. Strajku Dokerów 5, Gdańsk Nowy Port 80-544. Praca została zrealizowana w 2020 roku w technice olejnej na płótnie. Jest to kompozycja złożona z dwudziestu części o wymiarach 38 x 55 cm. Wymiary pracy: 167 x 295 cm. Czas trwania wystawy: 6 marca - 28 czerwca 2020.
ALTERNATIVE, DIRECT SYNTHESIS METHOD OF THE CERAMIC SOLID SOLUTIONS BASED ON BaTiO3 THROUGH A HIGH ENERGY BALL MILLING
- Wojciech Bąk
- Piotr Dulian
- Barbara Garbarz-Glos
- Dionizy Czekaj
- Agata Lisińska-Czekaj
2020 Pełny tekst ARCHIVES OF METALLURGY AND MATERIALS
Polycrystalline samples BaTiO3 and the solid solutions Ba0.9Sr0.1TiO3, Ba0.9Sr0.1Ti0.9Sn0.1O3, Ba0.9Sr0.1Ti0.8Sn0.2O3 were obtained by means of a mechanochemical treatment based on the high-energy ball milling technique and next a high temperature solid state reaction method. The influence of synthesis condition on microstructural, dielectric and ferroelectric properties of obtained solid solutions were investigated. The structure and morphology of the investigated samples were characterized by an X-ray diffraction (XRD) and scanning electron microscopy (SEM). The characterization of electrical properties of the ceramics within the temperature range from –130°C to 250°C were performed by means of a dielectric spectroscopy method at the frequency ranging from 0.1 Hz to 10 MHz. The diffusion of the paraelectric – ferroelectric phase transition and dielectric relaxation for ceramic samples are described.