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Search results for: UNIAXIAL STRETCH
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Highly Dissipative Materials for Damage Protection against Earthquake-Induced Structural Pounding
PublicationIt is a common situation that seismic excitations may lead to collisions between adjacent civil engineering structures. This phenomenon, called earthquake-induced structural pounding, may result in serious damage or even the total collapse of the colliding structures. Filling the gap between two buildings erected close to one another by using visco-elastic materials can be considered to be one of the most effective methods to avoid...
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Blowing Kinetics, Pressure Resistance, Thermal Stability, and Relaxation of the Amorphous Phase of the PET Container in the SBM Process with Hot and Cold Mold. Part I: Research Methodology and Results
PublicationThe technology of filling drinks without preservatives (such as fresh juices, iced tea drinks, vitaminized drinks) is carried out using hot filling. Mainly due to the production costs and lower carbon footprint, polyethylene terephthalate bottles, commonly called PET, are increasingly used in this technology. In this paper, the main aim is to describe the statistical analysis methodology of the influence of the temperature of the...
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Blowing Kinetics, Pressure Resistance, Thermal Stability, and Relaxation of the Amorphous Phase of the PET Container in the SBM Process with Hot and Cold Mold. Part II: Statistical Analysis and Interpretation of Tests
PublicationThe technology of filling drinks without preservatives (such as fresh juices, iced tea drinks, and vitaminized drinks) is carried out using hot filling. Mainly due to the production costs and lower carbon footprint, polyethylene terephthalate (PET) bottles are increasingly used in this technology. In this paper, the main aim is to describe and interpret the results of statistical analysis of the influence of the temperature of...
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Buckling Analysis of a Micro Composite Plate with Nano Coating Based on the Modified Couple Stress Theory
PublicationThe present study investigates the buckling of a thick sandwich plate under the biaxial non-uniform compression using the modified couple stress theory with various boundary conditions. For this purpose, the top and bottom faces are orthotropic graphene sheets and for the central core the isotropic soft materials are investigated. The simplified first order shear deformation theory (S-FSDT) is employed and the governing differential...
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Optymalizacja doboru prawa konstytutywnego membrany o strukturze plecionej
PublicationCelem niniejszej dysertacji jest opracowanie zagadnienia optymalizacyjnego pozwalającego dobrać model konstytutywny opisujący mechaniczne zachowanie membrany technicznej. Do analizy wybrano membrany plecione, stosowane w medycynie, tzw. siatki chirurgiczne. W celu wykonania identyfikacji praw konstytutywnych, wykonano dwuosiowe rozciąganie próbek materiałów, otrzymując wskazanie na nieliniowe anizotropowe zachowanie materiałów....
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Jacek Krenz : City in my eyes
PublicationSketch City: Tips and Inspiration for Drawing on Location is the companion for any creative traveler, urban explorer, or budding artist. 50 artists scattered around the globe have been brought together to share tips about their favorite urban settings, including locations in South America, Europe, Canada, Asia, and beyond. Citified sketchers are guiding through techniques for capturing frenetic street scenes as well as the rare...
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Accurate modeling of quasi-resonant inverter fed IM drive
PublicationIn this paper wide-band modeling methodology of a parallel quasi-resonant dc link inverter (PQRDCLI) fed induction machine (IM) is presented. The modeling objective is early-design stage prediction of conductive electromagnetic interference (EMI) emissions of the considered converter fed IM drive system. Operation principles of the selected topology of PQRDCLI feeding IM drive are given. Modeling of the converter drive system is...
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Effective configuration of a double triad planar parallel manipulator for precise positioning of heavy details during their assembling process
PublicationIn the paper, dynamics analysis of a parallel manipulator is presented. It is an atypical manipulator, devoted to help in assembling of heavy industrial constructions. Few atypical properties are required: small workspace; slow velocities; high loads. Initially, a short discussion about definition of the parallel manipulators is presented, as well as the sketch of the proposed structure. In parallel, some definitions, assumptions...
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Optimization of condition for demineralization Baltic cod (Gadus morhua) backbone
PublicationKręgosłupy dorsza bałtyckiego (Gadus morhua) są alternatywnym źródłem kolagenu. Aby uzyskać z nich natywny niezanieczyszczony kolagen należy usunąć z nich białka mięśniowe i sole mineralne. Obecność tych związków pogarsza funkcjonalne właściwości preparatu kolagenowego. Dlatego celem pracy było opracowanie optymalnych parametrów demineralizacji kręgosłupów dorsza. Najlepszy efekt demineralizacji, nieomal 100%, przy stratach tylko...
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Wpływ budowy stopni wejściowych falowników na generowanie prądów wirowych i upływowych
PublicationPodstawowymi rozwiązaniami stopni wejściowych falowników są układy z:-prostownikiem 6-pulsowym stosowanym dla obniżenia kosztów,-prostownikiem 12 lub 18-pulsowym stosowanym dla obniżenia zniekształceń harmonicznych,- sterowanym prostownikiem 6-pulsowym PWM stosowanym dla obniżenia zniekształceń harmonicznych oraz zwiększenia współczynnika mocy.Zawartość harmonicznych po stronie zasilania ma wpływ na możliwość powstania potencjalnych...
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GNIAZDA PRZEDSIĘBIORCZOŚCI W STREFIE PODMIEJSKIEJ METROPOLII
PublicationProblem suburbanizacji jest wciąż aktualny w analizach rozwoju miast. Przybiera często formy spontanicznego rozlewania się miast (urban sprawl). Badacze tego problemu skupiają się przeważnie na rozwoju funkcji mieszkaniowej w strefach podmiejskich. Specyficzny charakter polskiego procesu suburbanizacji polega na równoległym rozwoju klasycznej suburbanizacji osiedleńczej oraz rozwoju mikro- oraz małych i średnich przedsiębiorstw....
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Effects of laser pulse duration in two-photon vision threshold measurements
PublicationPulsed near-infrared (NIR) light sources can be successfully applied for both imaging and functional testing of the human eye, as published recently1. These two groups of applications have different requirements. For imaging applications, the most preferable is invisible scanning beam while efficiently visible stimulating beam is preferable for functional testing applications. The functional testing of human eye using NIR laser...
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Some geomechanical properties of a biopolymer treated medium sand
PublicationSome geomechanical properties of a biopolymer treated medium sand. This paper presents a laboratory assessment of geomechanical properties of sandy soil improved by biopolymer application. Additives (biosubstance) consist of polysaccharides and water. Biosubstance used in the project was xanthan gum, which comes from bacteria Xanthomonas campestris. Triaxial shear compression tests and unconfi ned compression tests were carried...
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Stiffness assessment of the laminate recovered from end-of-life wind turbine blade
PublicationIn the paper the stiffness parameters of the laminate recovered from an aerodynamic shell of a decommissioned wind turbine blade are evaluated. The aim of the work is to assess selected methods for identifying material data, as well as to estimate the level of stiffness degradation during turbine operation. Several practical identification methods are presented and compared. Two concepts of a single laminate layer are considered,...
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The effective elastic properties of human trabecular bone may be approximated using micro-finite element analyses of embedded volume elements.
PublicationBoundary conditions (BCs) and sample size affect the measured elastic properties of cancellous bone. Samples too small to be representative appear stiffer under kinematic uniform BCs (KUBCs) than under periodicity-compatible mixed uniform BCs (PMUBCs). To avoid those effects, we propose to determine the effective properties of trabecular bone using an embedded configuration. Cubic samples of various sizes (2.63, 5.29, 7.96, 10.58...
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Aluminum-TiO2 NPs Composites as Non-precious Catalysts for Efficient Electrochemical Generation of Hydrogen
PublicationIn this paper, we demonstrated, for the first time, aluminum titania nanoparticle (Al-TiO2 NP) composites with variable amounts of TiO2 NPs as nonprecious active catalysts for the electrochemical generation of H2. These materials were synthesized by mixing desired amounts of hydrogen titanate nanotubes (TNTs), fabricated here by a cost-effective approach at moderate hydrothermal conditions, with aluminum powder (purity 99.7%; size...
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Influence of selected WMA additives on viscoelastic behaviour of asphalt mixes and pavements
PublicationWarm mix asphalt additives are effective in decreasing production, laying and compaction temperatures of asphalt mixes. However, there are still questions concerning influence of warm mix additives on properties of asphalt mixes and pavement performance. This paper presents results of the comprehensive research of viscoelastic behaviour of asphalt mixes and pavement structures with layers made with warm mix asphalt additives at...
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Fractal dimension for bending–torsion fatigue fracture characterisation
PublicationFracture surfaces after biaxial fatigue tests were compared using fractal dimension for three types of metallic materials in smooth and notched specimens made of S355J2 and 10HNAP steels and 2017-T4 aluminium alloy, considering both proportional and nonproportional cyclic loading. High-resolution optical 3D measurement studies were performed on the entire fracture surface. A direct correlation between fractal dimension and fatigue...
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Valence and Ionic Lowest-Lying Electronic States of Isobutyl Formate Studied by High-Resolution Vacuum Ultraviolet Photoabsorption, Photoelectron Spectroscopy, and Ab Initio Calculations
PublicationThe highest resolution vacuum ultraviolet photoabsorption spectrum of isobutyl formate, C5H10O2, yet reported is presented over the energy range 4.5−10.7 eV (275.5−118.0 nm) revealing several new spectral features. Valence and Rydberg transitions and their associated vibronic series observed in the photoabsorption spectrum have been assigned in accordance with new ab initio calculations of the vertical excitation energies and oscillator...
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Wytwarzanie i modyfikacja powierzchni porowatych struktur tytanowych przeznaczonych na implanty
PublicationCelem pracy było wytworzenie stopu Ti-13Nb-13Zr z wykorzystaniem technologii selektywnego topienia laserowego (SLM) oraz jego biofunkcjonalizacja za pomocą utleniania mikrołukowego (MAO), a następnie określenie wpływu parametrów procesowych na właściwości otrzymanych materiałów pod kątem ich zastosowania na implanty. Oceniono wpływ napięcia, natężenia i czasu procesu MAO przeprowadzanego w elektrolicie zawierającym wapń i fosfor...
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Analytical predictions for the buckling of a nanoplate subjected to non-uniform compression based on the four-variable plate theory
PublicationIn the present study, the buckling analysis of the rectangular nanoplate under biaxial non-uniform compression using the modified couple stress continuum theory with various boundary conditions has been considered. The simplified first order shear deformation theory (S-FSDT) has been employed and the governing differential equations have been obtained using the Hamilton’s principle. An analytical approach has been applied to obtain...
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Wykorzystanie chromatografii jonowej w analityce jonów cyjankowych
PublicationNazwa cyjanki obejmuje związki, które zawierają w swojej cząsteczce grupę –C≡N, w której atom węgla i azotu są połączone wiązaniem potrójnym. Są to trujące i niebezpieczne związki, które znalazły swoje zastosowanie w różnych dziedzinach. Cyjanki wykorzystywane są w różnych strefach działalności przemysłowej, włączając w to przemysł wydobywczy i chemiczny. Naturalnym źródłem cyjanków są rośliny m.in. maniok, migdały, fasola, siemię...
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Kompozytowa skrzynkowa kładka pieszo-rowerowa: projektowanie, modelowanie i badania numeryczne
PublicationZaprojektowano kompozytową kładkę pieszo-rowerową, o ustroju nośnym skrzynkowym otwarto-zamkniętym, utworzonym przez sklejenie dwóch powłok kompozy-towych winyloestrowo-szklanych. Wzmocnienie stanowią tkaniny zrównoważone zszywane o gęstości powierzchniowej 800 g/m2 i orientacji włókien [0/90] i [45/–45] w stosunku do osi kładki. Kładka jest swobodnie podparta, o rozpiętości 12,00 m i szerokości użytkowej 2,50 m. Sprawdzono trzy...
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Properties of Nanohydroxyapatite Coatings Doped with Nanocopper, Obtained by Electrophoretic Deposition on Ti13Zr13Nb Alloy
PublicationNowadays, hydroxyapatite coatings are the most common surface modification of long-term implants. These coatings are characterized by high thickness and poor adhesion to the metallic substrate. The present research is aimed at characterizing the properties of nanohydroxyapatite (nanoHAp) with the addition of copper nanoparticle (nanoCu) coatings deposited on the Ti13Zr13Nb alloy by an electrophoresis process. The deposition of...
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Self-Supervised Learning to Increase the Performance of Skin Lesion Classification
PublicationTo successfully train a deep neural network, a large amount of human-labeled data is required. Unfortunately, in many areas, collecting and labeling data is a difficult and tedious task. Several ways have been developed to mitigate the problem associated with the shortage of data, the most common of which is transfer learning. However, in many cases, the use of transfer learning as the only remedy is insufficient. In this study,...
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Creating Polish space language dictionary - lessons learned
PublicationPolish space industry suffers from lack of space vocabulary. Since joining European Space Agency in 2012, the sector has expanded rapidly now employing over 1000 specialists focusing mainly on space sustainability, space debris detection and tracking, robotics and propulsion systems. The Polish Space Agency together with The Polish Committee for Standardization have committed to creating the first lexicon of space language, along...
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Road Infrastructure Safety Management in Poland
PublicationThe objective of road safety infrastructure management is to ensure that when roads are planned, designed, built and used road risks can be identified, assessed and mitigated. Road transport safety is significantly less developed than that of rail, water and air transport. The average individual risk of being a fatality in relation to the distance covered is thirty times higher in road transport that in the other modes. This is...
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Insight into (Electro)magnetic Interactions within Facet-Engineered BaFe12O19/TiO2 Magnetic Photocatalysts
PublicationA series of facet-engineered TiO2/BaFe12O19 composites were synthesized through hydrothermal growth of both phases and subsequent deposition of the different, faceted TiO2 nanoparticles onto BaFe12O19 microplates. The well-defined geometry of the composite and uniaxial magnetic anisotropy of the ferrite allowed alternate interfaces between both phases and fixed the orientation between the TiO2 crystal structure and the remanent...
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Wpływ zderzaków na odpowiedź kolidujacych ze sobą konstrukcji stalowych poddanych obciążeniom sejsmicznym
PublicationXXI wiek oraz bardzo wysoki poziom urbanizacji stanowi duże wyzwanie dla inżynierów. Stopień zagęszczenia budynków, z uwagi na coraz mniejsze możliwości wykorzystywania terenów pod zabudowę, jest ważnym czynnikiem branym pod uwagę podczas projektowania budynków – szczególnie tych, które leżą w strefach zagrożonych wstrząsami sejsmicznymi. Obciążenia sejsmiczne są jednymi z najbardziej nieprzewidywalnych i katastrofalnych w skutkach...
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Characteristics of silver-dopped carbon nanotube coating destined for medical applications
PublicationCarbon nanotubes are materials demonstrating outstanding mechanical, chemical, and physical properties and are considered coatings of titanium implants. The present research is aimed to characterize the microstructure and properties of the multi-wall carbon nanotubes (MWCNTs) layer decorated with silver nanoparticles (Ag NPs) on the Ti13Nb13Zr alloy destined for long-term implants. The electrophoretic deposition of coatings...
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Simulations of hydro-fracking in rock mass at meso-scale using fully coupled DEM/CFD approach
PublicationThe paper deals with two-dimensional (2D) numerical modelling of hydro-fracking (hydraulic fracturing) in rocks at the meso-scale. A numerical model was developed to characterize the properties of fluid-driven fractures in rocks by combining the discrete element method (DEM) with computational fluid dynamics (CFD). The mechanical behaviour of the rock matrix was simulated with DEM and the behaviour of the fracturing fluid flow...
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Lessons learned during SRAD hybrid motor development
PublicationStudent Researched and Developed (SRAD) hybrid rocket motor H-15 with total impulse of 15 $kNs$ was built. First version of the engine has average thrust of 3 $kN$, the second, improved one is prepared with an aim to have average thrust of 5 $kN$. Engine development was started from scratch and went through phases of: definition of design assumptions and constraints, numerical modelling to predict engine performance, CAD and CAM...
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Two-photon perimetry utilizing picosecond laser
PublicationAge-related impairments are becoming more and more severe for aging societies. The sensory organ diseases are particularly troublesome as they exclude seniors from their everyday activity. Therefore, maintaining good quality eyesight is essential for normal functioning. New medical therapies help restrain age-related changes, but still, monitoring is essential to the treatment process. Humans do not have the natural ability to...
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Extremal thermal loading of a bifurcation pipe
PublicationThe subject of considerations is a spherical bifurcation pipe of a live steam made of steel P91, which is an element of a block of coal-fired power plant working with a 18K370 turbine. As experience shows, it is a very sensitive element of the boiler pipelines. An extreme work scenario for such a block has been adopted, in which the turbine is shutting down to a warm state three times in 24 hours. This is an action dictated by...
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Enhanced Spectroscopic Insight into Acceptor-Modified Barium Strontium Titanate Thin Films Deposited via the Sol–Gel Method
PublicationIn the present paper, composite thin films of barium strontium titanate (BaxSr1−xTiO3) with an acceptor modifier (magnesium oxide—MgO) were deposited on metal substrates (stainless steel type) using the sol–gel method. The composite thin films feature BaxSr1−xTiO3 ferroelectric solid solution as the matrix and MgO linear dielectric as the reinforcement, with MgO concentrations ranging from 1 to 5 mol%. Following thermal treatment...
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Progress in the post weld residual stress evaluation using Barkhausen effect meter with a novel rotating magnetic field probe
PublicationWe report the progress in post weld residual stress evaluation using Barkhausen effect (BE) meter with rotating magnetic field probe. The novel probe of the BE meter contains two C-core electromagnets and searching coil with ferrite antenna. This meter allows automatic measurements of BE intensity envelopes at different angles of magnetizing field. The full process of measurement at given position of the probe takes about only...
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Artificial Thermal Ageing of Polyester Reinforced and Polyvinyl Chloride Coated Technical Fabric
PublicationArchitectural fabric AF9032 has been subjected to artificial thermal ageing to determine changes of the material parameters of the fabric. The proposed method is based on the accelerated ageing approach proposed by Arrhenius. 300 mm x 50 mm samples were cut in the warp and fill directions and placed in a thermal chamber at 80 °C for up to 12 weeks or at 90 °C for up to 6 weeks. Then after one week of conditioning at ambient temperature,...
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Powder metallurgy of the porous Ti-13Nb-13Zr alloy of different powder grain size
PublicationThe objective of the present project was to determine the effects of powder granulation (fraction of grain size) for the Ti-13Nb-13Zr alloy, produced by powder metallurgy, on its porosity, grain cohesion, compressive strength, and Young`s modulus. Two powder fractions, 45–105 µm, and 106–250 µm were applied. The 50 mass pct of NH4HCO3 was added as a space holder. The specimens were in compaction stage uniaxially pressed at pressure...
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Adaptive Positioning Systems Based on Multiple Wireless Interfaces for Industrial IoT in Harsh Manufacturing Environments
PublicationAs 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...
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The role and importance of total organic carbon (TOC) in production chain of KGHM Polska Miedż S.A. = Rola i znaczenie węgla organicznego w ciągu produkcyjnym realizowanym w KGHM Polska Miedź S.A.
PublicationWęgiel organiczny ma szczególne znaczenie w procesach realizowanych w ciągu technologicznym KGHM Polska Miedź S.A. Obecność węgla organicznego i złożoność problemów z nim związanych wynika głównie z jego występowania we wszystkich fazach tworzenia się złoża, a obecnie ma znaczący wpływ zarówno na przebieg procesu wzbogacania, jakość koncentratu, jak również na procesy ogniowe w technologii pieca zawiesinowego. Jednocześnie forma...
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Zagrożenia dla środowiska naturalnego w działaniach firm regionu gdańskiego związanych z organizacją EURO 2012 a współpraca PPP
PublicationSukces ekonomiczny przedsiębiorców w Gdańsku może być wiekszy, jeżeli losowanie druzyn rozgrywających mecze w Gdańsku będzie korzystne. Jeśli druzyny europejskie przyjadą do Gdańska wraz ze swoimi kibicami, przedsiebiorca branż hotelowej i gastronomicznej mogą uzyskać wieksze dochody. Należy mieć na uwadze ochronę wód powierzchniowych i podziemnych Gdańska. Główne ujęcia wód podziemnych znajdują się w sąsiedztwie stadionu PGE...
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Przewodnik Architektoniczny=Architectural Guide=Architekturführer. Gdynia
PublicationGdynia is a unique city that is particularly interesting for architects due to its homogeneous architecture. The city, based on the structure of an earlier fishing village, was entirely designed and built from scratch in the interwar period, as was the case later for cities such as Brasilia and Chandigarh. Today, Gdynia is a modern port town that forms the Tri-City metropolitan area together with Gdańsk, the city of amber, and...
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Significant Production of Thermal Energy in Partially Ionized Hyperbolic Tangent Material Based on Ternary Hybrid Nanomaterials
PublicationNanoparticles are frequently used to enhance the thermal performance of numerous materials. This study has many practical applications for activities that have to minimize losses of energy due to several impacts. This study investigates the inclusion of ternary hybrid nanoparticles in a partially ionized hyperbolic tangent liquid passed over a stretched melting surface. The fluid motion equation is presented by considering the...
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Updating a hospital building. A task for innovation design
PublicationRefurbishment of a hospital, especially located in a historical building, is a task that goes far beyond a standard framework of architectural practice. A concept of modularity in the architecture of the late nineteenth and early twentieth century was only just to happen, building system installations and technical equipment appeared as the simplest solutions. Inscribing complex functional solutions into such a space is an interesting...
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Analiza egzergetyczna bloku gazowo parowego współpracującego z obiegiem ORC
PublicationW pracy przedstawiono sposób przeprowadzania bilansu egzergetycznego dla obiegu Clausiusa – Rankina. Następnie przy pomocy programu EES współpracującego z bazą REFPROP 9.0 (Reference Fluid Thermodynamic and Transport Properties Database) [6] wykonany został bilans egzergetyczny dla układu kaskadowego siłowni CCGT – ORC, w którym blok gazowo – parowy współpracuje z obiegiem ORC. Obliczenia wykonano w oparciu o rzeczywiste parametry...
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Effects of Micro-Arc Oxidation Process Parameters on Characteristics of Calcium-Phosphate Containing Oxide Layers on the Selective Laser Melted Ti13Zr13Nb Alloy
PublicationTitania-based films on selective laser melted Ti13Zr13Nb have been formed by micro-arc oxidation (MAO) at different process parameters (voltage, current, processing time) in order to evaluate the impact of MAO process parameters in calcium and phosphate (Ca + P) containing electrolyte on surface characteristic, early-stage bioactivity, nanomechanical properties, and adhesion between the oxide coatings and substrate. The surface...
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Technologie prośrodowiskowe dla budynków miejskich
PublicationWspółczesne duże miasta na całym świecie charakteryzują się dużą i wciąż rosnącą intensywnością zabudowy. Jest to tendencja utrwalona, którą pogłębia idea „miasta zwartego” jako rozwiązania dla problemu nadmiernego rozrastania terytorialnego i rozpraszania się struktury terenów miejskich. Jednocześnie realną potrzebą współczesnych miast jest poprawa jakości ich środowiska (eliminacja zanieczyszczeń, minimalizacja zjawiska miejskiej...
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Evaluation of adhesion strength, corrosion, and biological properties of the MWCNT/TiO2 coating intended for medical applications
PublicationMulti-wall carbon nanotube (MWCNT) coatings are gaining increasing interest because of their special properties used in many science fields. The titania coatings are known for their improvement of osteoblast adhesion, thus changing the surface architecture. Bi-layer coatings comprising 0.25 wt% of the MWCNTs and 0.30 wt% of titania (anatase structure) were synthesized in a two-stage procedure using the electrophoretic deposition...
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Goblet Cell Ratio in Combination with Differentiation and Stem Cell Markers in Barrett Esophagus Allow Distinction of Patients with and without Esophageal Adenocarcinoma
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Polygons vs. clumps of discs: A numerical study of the influence of grain shape on the mechanical behaviour of granular materials
PublicationWe performed a series of numerical vertical compression tests on assemblies 01 20 granular material using a Discrete Element code and studied the results with regard to the grain shape. The samples consist of 5000 grains made from either 3 overlapping discs (clumps - grains with concavities) or six-edged polygons (convex grains). These two grain type have similar external envelope, which is a fund ion of a geometrical parameter...