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Voltage and Reactive Power Load Flow Optimization in the Power System Using Fuzzy Logic
PublicationThe paper presents issues related to voltage control in the power system. An original method of reactive power flow optimization is considered, which leads to improved voltages in the power system and reduced active power losses. The optimization method is based on a procedure that employs fuzzy logic and is supported by a gradient search algorithm. The method has been implemented in PLANS software and verified.
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System of protection against electric shock for circuits with power electronics converters
PublicationModern low voltage circuits are very often equipped with power electronics converters, therefore in these circuits non-sinusoidal earth currents (touch currents) may occur. For non-sinusoidal currents safety criteria should be modified. This paper presents these modified criteria and a computer system of protection against electric shock which can be implemented in circuits with power electronics converters. The system is based...
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[Soft Skills] Smart metering - social risk perception and risk governance (2023/2024)
e-Learning CoursesThe aim of the course is to broaden the understanding of the risks associated with technology and to present the concept of social risk perception and risk management in the context of smart metering technology. In the current phase of technological development - called the Fourth Industrial Revolution - rapid and profound changes are creating new, particularly destabilizing threats. In the increasingly complex technological systems...
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Eco-friendly modification of bitumen: The effects of rubber wastes and castor oil on the microstructure, processability and properties
PublicationThe bitumen industry in the European Union is facing several difficulties, including rising demand, unstable oil supply, rising prices for synthetic polymer modifiers, and a focus on lowering carbon footprint. Bitumen modification with crumb rubber (CR) is one of the most promising solution to these challenges. However, CR-modified bitumen have poor processability and low storage stability. To overcome these flaws we are introducing...
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Analysis and assessment of the acoustic emission suitability for determination of the energy states of a tribological system in the form of a four-ball tester friction node
PublicationThe present operating safety and cost reduction requirements of the compression ignition engines make it necessary to search for new methods of detecting their defects, e.g. by the analysis of acoustic emission signals coming from the slide bearings. The paper presents non-destructive measurements of acoustic emission (AE) in order to obtain information on the processes taking place in a tribological system under the continuously...
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Bacteriophages as an antistaphylococcal agent
PublicationRecently observed increase of infection caused by Staphylococcus aureus is currently one of the most important problem of clinical microbiology. Most of the strains responsible for the infections are a MRSA (methicillin resistant Staphylococcus aureus) strains. In this situation commonly used antibiotics are not sufficient. There is an urgent need to search for a new nonatibiotic treatment against this pathogen. In the literature...
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SOME PROBLEMS OF SUPPORTING OFFSHORE WIND TURBINES
PublicationBasic problems of foundations of sea wind turbines are considered in this paper. This aims to search for solutions to optimize supporting of the offshore turbines with a size greater than 10 MW. The types of foundations, their basic features, including most important dimensions, applications as well as general design considerations are discussed. Numerical model of the offshore turbine and some preliminary computations for a case...
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Auditory-visual attention stimulator
PublicationNew approach to lateralization irregularities formation was proposed. The emphasis is put on the relationship between visual and auditory attention stimulation. In this approach hearing is stimulated using time scale modified speech and sight is stimulated by rendering the text of the currently heard speech. Moreover, displayed text is modified using several techniques i.e. zooming, highlighting etc. In the experimental part of...
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Refined theoretical study of radiative association: Cross sections and rate constants for the formation of SiN
PublicationRadiative association of silicon mononitride (SiN) in its two lowest molecular electronic states is studied through quantum and classical dynamics. Special attention is paid to the behavior of the cross section at high collision energies. A modified expression for the semiclassical cross section is presented which excludes transitions to continuum states. This gives improved agreement with quantum mechanical perturbation theory...
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Synthesis of thiol derivatives of azobenzocrown ethers. The preliminary studies on recognition of alkali metal ions by gold nanoparticles functionalized with azobenzocrown and lipoic acid
PublicationThe article presents the synthesis of novel 13- and 16-membered azobenzocrown derivatives with peripheral thiol moieties and preliminary studies assessing their possible application in plasmonic sensors based on gold nanoparticles. The effect of the length of the chain connecting the macrocycle with the thiol group and the effect of the presence of the additional functional compound,...
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Modification of cellulosic filler with diisocyanates – volatile organic compounds emission assessment and stability of chemical structure over time
PublicationThis paper investigated the impact of type and content of diisocyanate on the structure of modified cellulose fillers. Four the most popular isocyanates were applied – isophorone, hexamethylene, toluene and methylene diphenyl diisocyanate – at loadings of 1–15 wt%. Chemical structure, and its short-term storage stability, were investigated for eight weeks. Moreover, the main volatile organic compounds detected during modification,...
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Dagmara Lisman PhD
PeopleScientist, biologist, forensic geneticist. She completed her master's studies at the West Pomeranian University of Technology in Szczecin, at the Faculty of Biology, and obtained a doctoral degree in forensic genetics at the Pomeranian Medical University in Szczecin. Currently, he works as an assistant at the Department of Forensic Medicine of the same university. Her research, conducted at the Department of Forensic Genetics at...
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Towards increasing F-measure of approximate string matching in O(1) complexity
PublicationThe paper analyzes existing approaches for approximate string matching based on linear search with Levenshtein distance, AllScan and CPMerge algorithms using cosine, Jaccard and Dice distance measures. The methods are presented and compared to our approach that improves indexing time using Locally Sensitive Hashing. Advantages and drawbacks of the methods are identified based on theoretical considerations as well as empirical evaluations...
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Microseismic Monitoring of Hydraulic Fracturing - Data Interpretation Methodology With an Example from Pomerania
PublicationMicroseismic monitoring is a method for localizing fractures induced by hydraulic fracturing in search for shell gas. The data is collected from an array of geophones deployed on the surface or underground. Ground vibrations are recorded and analysed for fracture location, magnitude and breakage mechanism. For successful microseismic monitoring one need a velocity model of underlying formations. The model is further tuned with...
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Smart metering - social risk perception and risk governance (10h, 2 ECTS credits)
e-Learning CoursesThe goal of the course is to broaden the understanding of technology-related risks and to present the concepts of social risk perception and risk governance in the context of smart metering technology. In current phase of technological development – known as the fourth industrial revolution – rapid and profound changes are setting up new and particularly destabilizing risks. In more and more complex technological systems that constitute...
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Modifications of total synthesis of mycophenolic acid
PublicationThe total synthesis of mycophenolic acid (MPA), a potent immunosuppressant, was modified. The obtained mycophenolic acid was suitable for further preparation of new prospective immunosuppressants with improved therapeutic properties.
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LOCAL E-MARKETING AND PHARAMACY SELECTION PROCESS AMONG CURRENT AND PROSPECTIVE CONSUMERS
PublicationWORK OBJECTIVES: To examine whether and to what extent a company's presence in Google Search mobile results, and Google Maps service search results, affects pharmacies' acquisition of new consumers RESEARCH QUESTIONS: Does the presence of pharmacies in Google MyBusiness increase the number of their customers ? Is the increase in the...
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Study of the effect of thermally reduced graphene oxide on the physical and mechanical properties of flexible polyurethane foams
PublicationFlexible polyurethane foams were obtained from a two-component system via the one-step method. The foams were modified with thermally reduced graphene oxide added in the amount equal to 0.25, 0.5 and 0.75 wt%. The morphology, static and dynamic properties, and thermal stability of modified foams were determined. The application of carbon filler resulted in the visible increase in the cell size, apparent density and rigidity of...
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Mono- and bi-metallic plasmonic photocatalysts for degradation of organic compounds under UV and visible light irradiation
PublicationTitania powders were surface modified with gold and/or silver nanoparticles (NPs) by photodeposition method. Gold modified titania exhibited much higher photocatalytic activity during methanol dehydrogenation under UV irradiation than titania modified with monometallic silver and bimetallic Au–Ag NPs. Bimetallic photocatalysts exhibited either enhanced or reduced visible light activity, depending on properties of noble metal NPs,...
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Impact of the Finite Element Mesh Structure on the Solution Accuracy of a Two-Dimensional Kinematic Wave Equation
PublicationThe paper presents the influence of the finite element mesh structure on the accuracy of the numerical solution of a two-dimensional linear kinematic wave equation. This equation was solved using a two-level scheme for time integration and a modified finite element method with triangular elements for space discretization. The accuracy analysis of the applied scheme was performed using a modified equation method for three different...
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Expedited optimization of antenna input characteristics with adaptive Broyden updates
PublicationSimulation-driven adjustment of geometry and/or material parameters is a necessary step in the design of contemporary antenna structures. Due to their topological complexity, other means, such as supervised parameter sweeping, does not usually lead to satisfactory results. On the other hand, rigorous numerical optimization is computationally expensive due to a high cost of underlying full-wave electromagnetic (EM) analyses, otherwise...
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High-Resolution Wind Wave Parameters in the Area of the Gulf of Gdańsk During 21 Extreme Storms
PublicationThis dataset contains the results of wind-wave parameter modelling in the area of the Gulf of Gdańsk (Southern Baltic). For the simulations, a high resolution SWAN model was used. The dataset consists of the significant wave height, the direction of the wave approaching the shore and the wave period during 21 historical, extreme storms. The storms were selected by an automatic search over the 44-year-long significant wave height...
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Modification of Titanium (IV) Dioxide with Small Silver Nanoparticles: Application in Photocatalysis
PublicationThe surface of commercial TiO2 compounds (P25 and ST01) has been modified with Ag nanoparticles induced by radiolysis. On P25, the Ag nanoclusters are very small (1−2 nm) and homogeneous in size while on ST01, two populations of nanoparticles are obtained, small nanoparticles (1−2 nm) and larger ones (mean diameter 7 to 12 nm depending on the silver loading). The photocatalytic properties of Ag-modified TiO2 have been studied for...
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Generating optimal paths in dynamic environments using RiverFormation Dynamics algorithm
PublicationThe paper presents a comparison of four optimisation algorithms implemented for the purpose of finding the shortest path in static and dynamic environments with obstacles. Two classical graph algorithms –the Dijkstra complete algorithm and A* heuristic algorithm – were compared with metaheuristic River Formation Dynamics swarm algorithm and its newly introduced modified version. Moreover, another swarm algorithm has been compared...
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Application of cyanated asphaltenes in gas-phase adsorption processes for removal of volatile organic compounds
PublicationThe paper presents an innovative, chemically modified (methylcyanated) asphaltene-based adsorbent that can be an inter-esting low-cost alternative for traditional adsorbents. Adsorption properties of adsorbents were examined by inverse gas chromatography technique, adsorption isotherms, and breakthrough curves. A significant increase in retention volume for pyridine, 2-pentanone, nitropropane, toluene, and 1-butanol was observed....
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Preparation and Characterization of Films Based on Disintegrated Bacterial Cellulose and Montmorillonite
PublicationThe food packaging materials from natural polymers including polysaccharides offer an ecologically important alternative to commonly used synthetic, non-biodegradable counterparts. The purpose of this work was to modify of bacterial cellulose (BC) leading to the improvement of its functional properties in terms of use as a food packaging material. Effects of disintegration of BC and addition of montmorillonite (MMT) on its water...
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Sensorless induction motor drive with voltage inverter and sine-wave filter
PublicationThis paper presents a speed sensorless control system of an induction motor with an output LC filter. It is known that the parameters design of the filter gives sine wave motor supply voltage but complicates control and estimation process. The reason is that the voltage drop and phase shift between filter input and output signals are imposed, and hence the motor voltages and currents differ from the inverter output waveforms. To...
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Language of Benefits as a Novel Tool for Improving Website Personalization
PublicationA properly designed website allows the user to search for information faster, and more accurately. The information content of the website should be also adapted to the needs of the user. The purpose of this article is to present a novel Language of Benefits (LoB) approach to facilitate the use of websites for individual user groups. The LoB approach is an approach addressed to IT Analysts, to facilitate the process of web design,...
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Protonic Ceramic Fuel Cells as novel electrochemical devices
PublicationProton ceramic conductors are novel materials which are interesting from the application point of view. For example, Protonic Ceramic Fuel Cells (PCFCs) is a type of a solid oxide fuel cell, which uses proton ceramic conductors as an electrolyte. Scientists are looking for the most efficient materials for these devices. In recent years main focus has been put on the search for new proton and mixed proton-electron conductors which...
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Modyfikacja cementu kostnego w celu uzyskania długotrwałej ochrony antybakteryjnej
PublicationNiniejsza rozprawa doktorska stanowi przewodnik po jednotematycznym cyklu publikacji, dotyczącym modyfikacji akrylowego cementu kostnego celem uzyskania długotrwałej i efektywnej ochrony antybakteryjnej. W ramach niego przeprowadzono badania eksperymentalne polegające na opracowaniu technologii wytwarzania modyfikowanego cementu kostnego oraz procedury medycznej jego stosowania. Cement kostny był modyfikowany przez zastosowanie...
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High-Efficacy Global Optimization of Antenna Structures by Means of Simplex-Based Predictors
PublicationDesign of modern antenna systems has become highly dependent on computational tools, especially full-wave electromagnetic (EM) simulation models. EM analysis is capable of yielding accurate representation of antenna characteristics at the expense of considerable evaluation time. Consequently, execution of simulation-driven design procedures (optimization, statistical analysis, multi-criterial design) is severely hindered by the...
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On Accelerated Metaheuristic-Based Electromagnetic-Driven Design Optimization of Antenna Structures Using Response Features
PublicationDevelopment of present-day antenna systems is an intricate and multi-step process requiring, among others, meticulous tuning of designable (mainly geometry) parameters. Concerning the latter, the most reliable approach is rigorous numerical optimization, which tends to be re-source-intensive in terms of computing due to involving full-wave electromagnetic (EM) simu-lations. The cost-related issues are particularly pronounced whenever...
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Influence of several biodegradable components added to pure and nanosilver-doped PMMA bone cements on its biological and mechanical properties
PublicationAcrylic bone cements (BC) are wildly used in medicine. Despite favorable mechanical properties, processability and inject capability, BC lack bioactivity. To overcome this, we investigated the effects of selected biodegradable additives to create a partially-degradable BC and also we evaluated its combination with nanosilver (AgNp). We hypothesized that using above strategies it would be possible to obtain bioactive BC. The Cemex...
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Estimation of Broadband Complex Permeability Using SIW Cavity-Based Multimodal Approach
PublicationIn this article, an attractive multimodal substrate integrated waveguide (SIW) based methodology is presented for the characterization of magnetic materials in the broadband microwave frequency. The proposed approach employs a modified feed under-coupled SIW cavity instead of conventional feed over-coupled multiple SIW cavities; it uses the modified closedform expression, developed from the first principle to consider the effect...
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Adjusting the Stiffness of Supports during Milling of a Large-Size Workpiece Using the Salp Swarm Algorithm
PublicationThis paper concerns the problem of vibration reduction during milling. For this purpose, it is proposed that the standard supports of the workpiece be replaced with adjustable stiffness supports. This affects the modal parameters of the whole system, i.e., object and its supports, which is essential from the point of view of the relative tool–workpiece vibrations. To reduce the vibration level during milling, it is necessary to...
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Fast EM-Driven Nature-Inspired Optimization of Antenna Input Characteristics Using Response Features and Variable-Resolution Simulation Models
PublicationUtilization of optimization technique is a must in the design of contemporary antenna systems. Often, global search methods are necessary, which are associated with high computational costs when conducted at the level of full-wave electromagnetic (EM) models. In this study, we introduce an innovative method for globally optimizing reflection responses of multi-band antennas. Our approach uses surrogates constructed based on response...
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Novel sugar-based nickel-tungsten carbide catalysts for dry reforming of hydrocarbons
PublicationThe search for new materials for dry reforming of hydrocarbons with high activity, stability, and ease of synthesis is still one of the main directions of research in the field of heterogeneous catalysis. Traditional methods of carbide synthesis require the use of combustible gases of petrochemical origin. The search for new catalysts based on renewable and safe carbon sources is highly demanded. Therefore, we report WC and Ni-WC...
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Globalized parametric optimization of microwave components by means of response features and inverse metamodels
PublicationSimulation-based optimization of geometry parameters is an inherent and important stage of microwave design process. To ensure reliability, the optimization process is normally carried out using full-wave electromagnetic (EM) simulation tools, which entails significant computational overhead. This becomes a serious bottleneck especially if global search is required (e.g., design of miniaturized structures, dimension scaling over...
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Design specification management with automated decision-making for reliable optimization of miniaturized microwave components
PublicationThe employment of numerical optimization techniques for parameter tuning of microwave components has nowadays become a commonplace. In pursuit of reliability, it is most often carried out at the level of full-wave electromagnetic (EM) simulation models, incurring considerable computational expenses. In the case of miniaturized microstrip circuits, densely arranged layouts with strong cross-coupling effects make EM-driven tuning...
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Near-Infrared III Nanophosphorswith Cr3+Ni2+ Energy Transfer for Bioimaging
Open Research DataIn the biomedical field, the use of fluorescence imaging in the second near-infrared (NIR-II) region is growing rapidly because it imparts the advantages of reduced autofluorescence and low photon scattering. The advantage of reduced scattering is that it increases penetration depth in vivo and improves imaging clarity. Herein, this work uses mesoporous...
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Computer experiments with a parallel clonal selection algorithm for the graph coloring problem
PublicationArtificial immune systems (AIS) are algorithms that are based on the structure and mechanisms of the vertebrate immune system. Clonal selection is a process that allows lymphocytes to launch a quick response to known pathogens and to adapt to new, previously unencountered ones. This paper presents a parallel island model algorithm based on the clonal selection principles for solving the Graph Coloring Problem. The performance of...
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Words context analysis for improvement of information retrieval
PublicationIn the article we present an approach to improvement of retrieval informationfrom large text collections using words context vectors. The vectorshave been created analyzing English Wikipedia with Hyperspace Analogue to Language model of words similarity. For test phrases we evaluate retrieval with direct user queries as well as retrieval with context vectors of these queries. The results indicate that the proposed method can not...
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Talents, Competencies and Techniques of Business Analyst: A Balanced Professional Development Program
PublicationThis paper presents preliminary results of action research in which we search for fundamentals of an universal theory of balanced approaches to software process. It is developed on the basis of balanced approach for professional development program for business analysts which integrates approaches oriented on talents, competencies and techniques. This paper includes the description of key concepts in background approaches, components...
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Morphology of bio-based polyurethane composites filled by mer-cerized or silanized natural fibres
PublicationBio-composites are materials which possess unique properties and undergo biodegra-dation under specific conditions. Bio-composites belong to the group of materials produced with the use of renewable raw materials. They contain reinforcement, mainly in the form of natural fiber, which has high stiffness and resistance; filler powders are less frequently used. Significant features of natural fibers are elongation, density, thermal...
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Rolling Resistance And Tire/Road Noise on Rubberized Asphalt Pavement In Poland
PublicationThe paper presents results of tire/road noise and rolling resistance measurements performed on stone-matrix asphalt (SMA) that contains rubberized asphalt developed and produced by the company in Poland. Bituminous binder was modified with polymer and additive of crumb rubber. First observations of asphalt mixture with the new kind of modified bitumen used on the field section are presented. Rolling resistance of passenger car...
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Rolling resistance and tyre/road noise on rubberised asphalt pavement in Poland
PublicationThe paper presents results of tyre/road noise and rolling resistance measurements performed on stone mastics asphalt (SMA) that contains rubberised asphalt, developed and produced by a refinery in Poland. Bituminous binder was modified with polymer and addition of crumb rubber. The first observations of asphalt mixture with the new kind of modified bitumen used on the field section are presented. Rolling resistance of passenger...
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High-performance method of carbon nanotubes modification by microwave plasma for thin composite films preparation
PublicationIn this work we present a simple and efficient method of nitrogen plasma modification of carbon nanotubes (CNTs). The process allows for treatment of the nanotubes in the form of powder with quite a high yield (65 mg of CNTs per hour). The modified carbon nanotubes contain approx. 3.8% of nitrogen, mostly in the pyridinic form. Plasma treated CNTs exhibit better dispersibility in water and higher electric capacitance than pristine...
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Multiple reference frame theory in the synchronous generator model considering harmonic distortions caused by nonuniform pole shoe saturation
PublicationThe paper describes a synchronous generator model developed based on the multiple reference frame theory. The main physical phenomena included in the model are the machine armature non-sinusoidal voltage waveform and the influence of armature current in load conditions on the armature voltage waveform higher harmonic components. The modified multiple reference frame theory model is proposed. In this modified theory model the field...
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Antibacterial properties of laser-encapsulated titanium oxide nanotubes decorated with nanosilver and covered with chitosan/Eudragit polymers
PublicationTo provide antibacterial properties, the titanium samples were subjected to electrochemical oxidation in the fluoride-containing diethylene glycol-based electrolyte to create a titanium oxide nanotubular surface. Afterward, the surface was covered by sputtering with silver 5 nm film, and the tops of the nanotubes were capped using laser treatment, resulting in an appearance of silver nanoparticles (AgNPs) of around 30 nm in diameter...
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Antibacterial polyurethanes, modifed with cinnamaldehyde, as potential materials for fabrication of wound dressings
PublicationThe epidermis is a skin layer, which protects an organism from the different factors of external environment. Therefore, the fast and effective regeneration of epidermis is important. Potential materials used for epidermis regeneration may be polyurethane scaffolds in form of the thin permeable layers. One and main disadvantage of such polyurethane scaffolds are their lack of antibacterial and antifungal properties. The great proposition...