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Cogging torque analysis based on energy approach in surface-mounted PM machines
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Precision surface characterization for finish cylindrical milling with dynamic tool displacements model
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Surface quality and topographic inspection of variable compliance part after precise turning
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Surface roughness analysis after machining of direct laser deposited tungsten carbide
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Surface properties of wustite based iron-cobalt catalysts for ammonia synthesis reaction
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The effect of manganese on the structural and surface properties of nanocrystalline cobalt catalyst for ammonia synthesis
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Experimental analysis on the risk of vortex ventilation and the free surface ventilation of marine propellers
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Lake surface changes of the Osa River catchment, (northern Poland), 1900–2010
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Structure and morphology of hydrogen reduced surface of bismuth germanateand bismuth silicate glasses.
PublicationOtrzymano nanostruktury krystalicznego bizmutu w matrycy XO2(X=Si,Ge) oraz warstwę nanostruktur krystalicznego bizmutu na powierzchni redukowanych w atmosferze wodoru szkieł Bi0.33Ge0.67O1. i Bi0.57Si0.43O1.72. Zaproponowano prosty model budowy zredukowanych szkieł bizmutowo-germanowych potwierdzony wynikami badań AFM i XRD. Obserwowane zmiany przewodnictwa elektrycznego redukowanych szkieł wyjaśniono na podstawie modelu.
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Laser assisted forming of the surface layer of Al-Si alloy at cryogenic conditions.
PublicationW artykule przedstawiono wpływ powierzchniowego laserowego przetapiania w warunkach kriogenicznych na mikrostrukturę, mikrotwardość i własności korozyjne stopu AlSi13Mg1CuNi. Stwierdzono korzystny wpływ obróbki laserowej na mikrostrukturę, mikrotwardość i odporność na zużycie ścierne badanego stopu aluminium.
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TiO2 photoactivity in vis and UV light: The influence of calcination temperature and surface properties
PublicationPrzygotowano serię fotokatalizatorów w postaci tlenku tytanu (IV) kalcynowanych w różnych temperaturach od 350 do 750˚C. Charakterystyka fotokatalizatorów za pomocą metod XRD, UV-Vis/DRS, FTIR, XPS, BET oraz BJH wykazała, że próbka TiO2 aktywna w świetle widzialnym posiadała strukturę anatazu, powierzchnię właściwą ok. 200 m2/g, absorbowała światło o długości fali λ>400 nm oraz zawierała 10,1 % at. węgla (wiązanie C-C). Aktywność...
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Determination (monitoring) of PAHs in surface waters: why operationally defined procedure is needed
PublicationW pracy przedstawiono i skomentowano rezultaty badań międzylaboratoryjnych oznaczania wielopierścieniowych węglowodorów aromatycznych w wodzie czystej i wodzie zawierającej zawiesinę. Badania wskazują, ze wyniki oznaczania zależa od zastosowanej techniki izolacji analitów z próbki i końcowej procedury ich rozdzielania i oznaczania. Przeprowadzone badania wskazują, że nowoczesna analityka nie dysponuje technikami izolacji, które...
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Organic Pollution in Surface Waters from the Fuglebekken Basin in Svalbard, Norwegian Arctic
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The phase composition of the surface layer of laser melted Ti-6Al-4V bioalloy
PublicationZastosowanie metody obróbki laserowej stopów Ti zwiekszyły twardość i odporność stopu na korozję. Jednakże uzyskane warstwy były stosunkowo cieńkie. W pracy zastosowano laser o dużej mocy dla stopu schłodzonego w ciekłym azocie, aby uzyskać grubszą warstwę, która w strefie zewnętrznej złożona będzie z tlenku i azotku tytanu, ważnych faz w biostopach.
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About nutrient liquid flow between potential flow and cartilage surface in bioreactor
PublicationW niniejszej pracy wyznaczony został przepływ cieczy odżywczej o właściwościach nienewtonowskich w cienkiej warstwie granicznej w pobliżu powierzchni komórek chrząstki (chondrocytu) podczas hodowli w bioreaktorze. Ruch cieczy w warstwie granicznej jest wywołany wydatkiem przepływu dostarczanej cieczy do bioreaktora. Ponadto prędkość przepływu cieczy w warstwie granicznej wokół hodowanych komórek chrząstki stawowej jest uzależniona...
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Influence of Laser Modification on the Surface Character of Biomaterials: Titanium and Its Alloys—A Review
PublicationLaser surface modification is a widely available and simple technique that can be applied to different types of materials. It has been shown that by using a laser heat source, reproducible surfaces can be obtained, which is particularly important when developing materials for medical applications. The laser modification of titanium and its alloys is advantageous due to the possibility of controlling selected parameters and properties...
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Tuning of the Titanium Oxide Surface to Control Magnetic Properties of Thin Iron Films
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Surface Characteristics of Plasma Treated and Titanium Nitride (TiN) Deposited Aluminum Alloy
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Surface Property Modification of Collagen, Hyaluronic Acid, and Chitosan Films with the Neodymium Laser
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EXPERIMENTAL STUDY OF SURFACE ROUGHNESS EFFECT ONTHE RHEOLOGICAL BEHAVIOR OF MR FLUID
PublicationPaper presents the results of shear stress measurements of a commercial magnetorheological fluid using a plate-plate type geometry with a modified working surface. The purpose of the study was to determine the effect of changing the roughness of the measuring plate on the obtained shear stress results. Controlled shear rate tests and Magneto Sweep measurements were carried out for three MR fluid layer heights. The tests were...
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Investigations of Energy Conversion and Surface Effect for Laser-Illuminated Gold Nanorod Platforms
PublicationAchieving a quick temperature increase is a burning issue for biophysical applications, like germ inactivation and tumor ablation, and for energy performances, like solar collectors and steam generators. Based on the plasmon resonance phenomenon, noble metallic nanoparticles have emerged as promising weapons due to their very high biocompatibility, optical properties, and high surface-to-volume ratio, increasing energy conversion...
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Conditions for measurement, analog-to-digital conversion and frequency analysis of irregularities of profile surface
PublicationPrzedstawiono uwarunkowania pomiaru, przetwarzania analogowo-cyfrowego i analizy częstotliwościowej nierówności powierzchni toczonych dla celów rozpoznawania ich głównych składowych. Przedstawiono ograniczenia w pomiarze igłą, która odwzorowuje nierówności poprzeczne. Podano zależności parametrów pomiaru cyfrowego nierówności warunkujące zakresy ich rozpatrywania. Dla wartości przedziału próbkowania, dla którego nie jest spełnione...
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Morphology and corrosion characteristics of laser surface remelted Al-Sialloy at cryogenic conditions
PublicationPrzedstawiono koncepcję obróbki laserowej stopu Al-Si w warunkach kriogenicznych. Określono jej wpływ na lokalny skład chemiczny oraz mikrostrukturę i właściwości korozyjne wymienionego stopu. Stwierdzono znaczącą poprawę właściwości korozyjnych w 0,01 M H2SO4.
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Application of 3D Whole Body Scanning in Research on Human Body Surface Area
PublicationHuman body surface area (BSA) is one of the major parameters used in several medical fields. Its heterogeneity caused by individual human characteristics sustains a many-decades-long research on the matter. Today’s technology allows to create exact body models in mere seconds. However, an extensive research that includes scanning people with major disfigurements or people suffering from diseases, which often prevent their mobility,...
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Influence of yttria surface modification on high temperature corrosion of porous Ni22Cr alloy
PublicationProtective coatings for porous alloys for high temperature use are relatively new materials. Their main drawback is high temperature corrosion. In this work protective coatings based the on Y-precursor infiltrated into the sintered Ni22Cr alloys are studied at 700°C. Effects of the amount of the protective phase on the resulting corrosion properties are evaluated in air and humidified hydrogen. Weight gain of the samples, their...
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Selected anionic and cationic surface active agents: case study on the Kłodnica sediments
PublicationSurface active agents (surfactants) are a group of chemical compounds, which are used as ingredients of detergents, cleaning products, cosmetics and functional products. After use, wastes containing surfactants or their degradation products are discharged to wastewater treatment plants or directly into surface waters. Due to their specific properties of SAAs, compounds are able to migrate between different environmental compartments...
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Design and Application of Magnetic Photocatalysts for Water Treatment. The Effect of Particle Charge on Surface
PublicationCore-interlayer-shell Fe3O4/SiO2/TiO2, CoFe2O4/SiO2/TiO2 and BaFe12O19/SiO2/TiO2 magnetic photocatalysts were obtained. A water-in-oil microemulsion system with suitable surfactants was used for functionalization of the magnetic core with silica interlayer and TiO2-based photocatalyst. Uncoated and coated particles were characterized by electrophoretic meaurements, X-ray diffractometry (XRD), scanning electron microscopy (SEM),...
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Transport of dangerous goods by rail, and threats to the subsoil of the railway surface in the event of a disaster
PublicationIn Poland, in 2020, the mass of dangerous goods (loads) transported by rail was 26 151.06 thousand tone. This translated into the performance of 8 899 691.89 thousand tone - km of transport performance. In 2020, these figures accounted for 11.72% of the weight of goods transported by rail. The situation is similar in other countries around the world. With such a large volume of transport of dangerous...
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On Effective Bending Stiffness of a Laminate Nanoplate Considering Steigmann–Ogden Surface Elasticity
PublicationAs at the nanoscale the surface-to-volume ratio may be comparable with any characteristic length, while the material properties may essentially depend on surface/interface energy properties. In order to get effective material properties at the nanoscale, one can use various generalized models of continuum. In particular, within the framework of continuum mechanics, the surface elasticity is applied to the modelling of surface-related...
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Mechanical and Corrosion Properties of Laser Surface-Treated Ti13Nb13Zr Alloy with MWCNTs Coatings
Publication: Titanium and its alloys is the main group of materials used in prosthetics and implantology. Despite their popularity and many advantages associated with their biocompatibility, these materials have a few significant disadvantages. These include low biologic activity—which reduces the growth of fibrous tissue and allows loosening of the prosthesis—the possibility of metallosis and related inflammation or other allergic reactions,...
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On weak solutions of boundary value problems within the surface elasticity of Nth order
PublicationA study of existence and uniqueness of weak solutions to boundary value problems describing an elastic body with weakly nonlocal surface elasticity is presented. The chosen model incorporates the surface strain energy as a quadratic function of the surface strain tensor and the surface deformation gradients up to Nth order. The virtual work principle, extended for higher‐order strain gradient media, serves as a basis for defining...
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Curved Surface Minijet Impingement Phenomena Analysed with ζ-f Turbulence Model
PublicationThe jet impingement phenomenon plays an important role among the heat transfer intensification methods. Very often its application and analyses refer to simple flat surfaces, while there is a lack of information in the literature for cases addressing curved surfaces. In the present work, the single jet impingement on the non-flat (concave and convex) surface is studied for a wide range of geometries, which originate from the mini-jet...
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Effect of surface on the flexomagnetic response of ferroic composite nanostructures; nonlinear bending analysis
PublicationOur analysis incorporates the geometrically nonlinear bending of the Euler-Bernoulli ferromagnetic nanobeam accounting for a size-dependent model through assuming surface effects. In the framework of the flexomagnetic phenomenon, the large deflections are investigated referring to von-Kármán nonlinearity. Employing the nonlocal effects of stress coupled to the gradient of strain generates a scale-dependent Hookean stress-strain...
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On the use of leading safety indicators in maritime and their feasibility for Maritime Autonomous Surface Ships
PublicationAlthough the safety of prospective Maritime Autonomous Surface Ships will largely depend on their ability to detect potential hazards and react to them, the contemporary scientific literature lacks the analysis of how to achieve this. This could be achieved through an application of leading safety indicators. The aim of the performed study was to identify the research directions of leading safety indicators in three safety-critical...
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Capacity of Surface Production of Band Sawing in Manufacture of Oak Floor Upper Layers
PublicationThin lamellae, corresponding to the layer components of structural glued members, i.e., 2-ply or 3-ply glued flooring, can be manufactured in re-sawing operations of kiln-dried wood blocks or in wet technologies, which currently seem to be more common because of the shorter drying time. The re-sawing process in wet technology is conducted on dedicated thin-cutting band sawing machines with stellite-tipped band saws. The goal of...
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Influence of Surface-Modified Montmorillonite Clays on the Properties of Elastomeric Thin Layer Nanocomposites
PublicationIn recent years, polyurethane nanocomposites have attracted more attention due to the massive demand for materials with increasingly exceptional mechanical, optical, electrical, and thermal properties. As nanofillers have a high surface area, the interaction between the nanofiller and the polymer matrix is an essential issue for these materials. The main aim of this study is to validate the impact of the montmorillonite nanofiller...
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Trace elements content of surface peat deposits in the Solovetsky Islands (White Sea)
PublicationPeatlands form environmental archives of trace element deposition. In this regard they are particularly valuable for areas such as the Arctic, where regular pollution monitoring is either impossible or extremely costly. The aim of this study was to assess pollution in the Solovetsky Islands (65° 05' N, 35° 53' E) by examining the spatial variability in trace element content of the uppermost layer of peat, immediately below the...
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Wireless Local Area Network Technologies as Communication Solutions for Unmanned Surface Vehicles
PublicationAs the number of research activities and practical deployments of unmanned vehicles has shown a rapid growth, topics related to their communication with operator and external infrastructure became of high importance. As a result a trend of employing IP communication for this purpose is emerging and can be expected to bring significant advantages. However, its employment can be expected to be most effective using broadband communication...
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Production and Properties of the Porous Layer Obtained by the Electrochemical Method on the Surface of Austenitic Steel
Publication: The growing demand for implants has seen increasing interest in the introduction of new technologies and surface modification methods of metal biomaterials. This research aimed to produce and characterize a porous layer grown on austenitic stainless steel 316L, obtained via the anodization process near the micro-arc oxidation, i.e., low voltage micro-arc oxidation (LVMAO). The discussed layer significantly influences the properties...
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Preliminary Results of a System-theoretic Assessment of Maritime Autonomous Surface Ships' Safety
PublicationWhile a system‐theoretic approach to the safety analysis of innovative socio‐technical systems gains a growing acceptance among academia, safety issues of Maritime Autonomous Surface Ships (MASS) remain largely unexplored. Therefore, we applied a System‐Theoretic Process Analysis to develop and analyze a preliminary model of the unmanned shipping system in order to elaborate safety recommendations for...
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Microstructure and mechanical properties of laser surface-treated Ti13nb13zr alloy with MWCNTs coatings
PublicationLaser surface modification of titanium alloys is one of the main methods of improving the properties of titanium alloys used in implantology. This study investigates the microstructural morphology of a laser-modified surface layer on a Ti13Nb13Zr alloy with and without a carbon nanotube coating deposited by electrophoretic deposition. Laser modification was performed for samples with and without carbon nanotube coating for two...
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Effectiveness of a dual surface modification of metallic interconnects for application in energy conversion devices
PublicationA dual surface modification of an SOFC metallic interconnect with a Gd2O3 layer and an MnCo2O4 coating was evaluated. The tested samples were oxidized for 7000 h in air at 1073 K. Oxidation products were characterized using XRD, SEM-EDS, and confocal Raman imaging, and ASR was measured. The effect of gadolinium segregation at grain boundaries in Cr2O3 was evaluated using S/TEM-EDS. Area specific-resistance was measured and fuel...
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Influence of Surface Modification of Titanium and Its Alloys for Medical Implants on Their Corrosion Behavior
PublicationTitanium and its alloys are often used for long-term implants after their surface treatment. Such surface modification is usually performed to improve biological properties but seldom to increase corrosion resistance. This paper presents research results performed on such metallic materials modified by a variety of techniques: direct voltage anodic oxidation in the presence of fluorides, micro-arc oxidation (MAO), pulse laser treatment,...
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Influence of Laser Modification on the Surface Character of Biomaterials: Titanium and Its Alloys—A Review
PublicationLaser surface modification is a widely available and simple technique that can be applied to different types of materials. It has been shown that by using a laser heat source, reproducible surfaces can be obtained, which is particularly important when developing materials for medical applications. The laser modification of titanium and its alloys is advantageous due to the possibility of controlling selected parameters and properties...
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Surface texture formation in precision machining of direct laser deposited tungsten carbide
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The effect of random surface topography height on fretting in dry gross slip conditions
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Application of surface active amino acid ionic liquids as phase-transfer catalyst
PublicationFive structurally related morpholinium derived ionic liquids containing N-acetyl-glycinate anion were synthesized and their thermal stability, surface properties and activity as phase transfer catalysts investigated. The thermal properties were studied by differential scanning calorimetry, while the adsorption at the air/water interface and micellization behavior was analyzed by surface tension measurements, conductometry and isothermal...
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Analysis of the Ways to Identify Rail Running Surface Defects by Means of Vibration Signals
PublicationTh e article discusses a preliminary concept of a method enabling the identifi cation of chosen rail running surface defects, such as squats, spalling, and running surface defects, by analysing the parameters of vibration signals. It features a description of the methodology of the conducted tests, the scope thereof, and the selection of the measurement points with specifi c defect types. Th e article covers selected results of...
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Reliability-Based Stability Analysis of a Baltic Cliff by the Combined Response Surface Method
PublicationA simple, straightforward computational procedure was proposed, incorporating the Response Surface Method (RSM) linked with the standard Monte Carlo (MC) simulation method and the Point Estimate Method (PEM). PEM samples make it possible to analyse the sensitivity of the cliff’s stability to variation in subsoil parameters and to reduce the number of random variables of the problem. The proposed methods were tested in two cases:...
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Measurements and calculations of the width of the fracture process zones on the surface of notched concrete beams
PublicationArtykuł omawia wyniki pomiaru i analizy numerycznej szerokości strefy pękania w belkach betonowych z nacięciem. Do pomiarów zastosowano metodę DIC. Do symulacji zastosowano model sprężysto - plastyczny i model z degradacją sztywności. Oba modele zostały rozszerzone o nielokalne osłabienie. Wyniki symulacji porównano z doświadczeniami.