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Role of quantitative chest perfusion computed tomography in detecting diabetic pulmonary microangiopathy
PublikacjaAims: Aimof the study was to determine the role of perfusion chest computed tomography(pCT) in evaluation of pulmonary diabetic angiopathy.Methods: 18 never-smoking patients (10 diabetic patients and 8 healthy controls) underwentchest high resolution CT (HRCT) and then pCT scanning. In both groups, blood tests,biochemical analysis, fibrinogen, HbA1c, spirometry, diffusion capacity for carbonmonoxide(DLCO) and body pletysmography...
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Inhibition of amyloid fibril formation of hen egg white lysozyme by trimethylamine N-oxide at low pH
PublikacjaIn vitro inhibition of the formation of fibrous aggregates of proteins (amyloids) has gained increasing attention due to the number of diseases associated with protein misfolding and fibrillation. An interesting group of compounds for which pronounced activity against this phenomenon can be expected consists of low molecular weight substances (osmolytes) which have the ability to change protein stability. Here we investigate the...
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Bounds on the cover time of parallel rotor walks
PublikacjaThe rotor-router mechanism was introduced as a deterministic alternative to the random walk in undirected graphs. In this model, a set of k identical walkers is deployed in parallel, starting from a chosen subset of nodes, and moving around the graph in synchronous steps. During the process, each node successively propagates walkers visiting it along its outgoing arcs in round-robin fashion, according to a fixed ordering. We consider...
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Ag/Pt-modified TiO2 nanoparticles for toluene photooxidation in the gas phase
PublikacjaAg/Pt-modified TiO2nanocomposites were synthesized using the sol–gel method. The effect of metal typeand amount as well as synthesis route on the photocatalytic activity in reaction of toluene removal, usedas a model volatile organic compound, was investigated. Toluene, at the concentration of about 200 ppm,was irradiated over modified TiO2using light-emitting diodes (LEDs, max= 415 nm). The results showedthat toluene could be...
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Numerical analysis of chip removing system operation in circular sawing machine using CFD software
PublikacjaPaper presents the analysis of the results of numerical simulations of the air flow process of wood chips removing system in the circular sawing machine. The attention is focused on the upper cover and bottom shelter of the chip removing system. Within the framework of the work a systematic numerical modeling of the air flow distribution in the cover and shelter during operation of the selected rotational speed of saw blade with...
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Wstępne wyniki projektu GDArms - odtwarzanie środowiska rakiety kosmicznej
PublikacjaW trakcie wynoszenia na ładunek rakiety działają przyspieszenia, drgania, przepływ ciepła oraz zmiany ciśnienia atmosferycznego. Według aktualnych norm i standardów, przed lotem testy środowiskowe są wykonywane sekwencyjnie. Autorzy przedstawili projekt urządzenia do odtwarzania środowiska rakiety kosmicznej. Urządzenie zostało zbudowane na bazie gotowego wzbudnika elektrodynamicznego. Zaprojektowano układy sterowania układów:...
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Production and Properties of the Porous Layer Obtained by the Electrochemical Method on the Surface of Austenitic Steel
Publikacja: 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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The assessment of metrological properties of segmental orifice based on simulations and experiments
PublikacjaSegmental orifices are often used to measure flows of heterogeneous mixtures, especially in flow meters in the power industry, for example. The orifice (with module m= 0.25) was installed in a stainless-steel pipe with internal diameter of 50 mm, placed in a hydraulic water system. The research was performed for Reynolds numbers ranging from 9,000 to 17,000. The flow characteristics of this orifice obtained based on simulation...
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Experimental study on models of cylindrical steel tanks under mining tremors and moderate earthquakes
PublikacjaThe aim of the study is to show the results of complex shaking table experimental investigation focused on the response of two models of cylindrical steel tanks under mining tremors and moderate earthquakes, including the aspects of diagnosis of structural damage. Firstly, the impact and the sweep-sine tests have been carried out, so as to determine the dynamic properties of models filled with different levels of liquid. Then,...
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Usefulness of chest perfusion computed tomography in the diagnosis of diabetic pulmonary microangiopathy
PublikacjaThis paper presents the usefulness of perfusion computed tomography (pCT) in the diagnosis of diabetic pulmonary microangiopathy. Our previous works have shown that perfusion parameters are useful in the diagnosis of diabetic pulmonary microangiopathy. We are looking for such measurements and perfusion parameters that provide the most accurate diagnosis. Two types of comparison were made based on the results of clinical trials:...
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Numerical analysis of elastic wave propagation in unbounded structures
PublikacjaThe main objective of this paper is to show the effectiveness and usefulness of the concept of an absorbing layer with increasing damping (ALID) in numerical investigations of elastic wave propagation in unbounded engineering structures. This has been achieved by the authors by a careful investigation of three different types of structures characterised by gradually increasing geometrical and mathematical description complexities....
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Biochemical characteristic of biofilm of uropathogenic Escherichia coli Dr+ strains.
PublikacjaUrinary tract infections caused by Escherichia coli are very common health problem in the developed countries. The virulence of the uropathogenic E. coli Dr+ IH11128 is determined by Dr fimbriae, which are homopolymeric structures composed of DraE subunits with the DraD protein capping the fiber. In this study, we have analyzed the structural and biochemical properties of biofilms developed by E. coli strains expressing Dr fimbriae...
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INFLUENCE OF SURFACE CURVATURE ON SESSILE DROPLET CONTACT ANGLE OF NANOFLUIDS
PublikacjaThis paper deals with change in contact angle of droplets of three nanofluids, i.e. water-Al2O3, water-TiO2 and water-Cu. Nanoparticles were tested at the concentration of 0.01%, 0.1%, and 1% by weight. Although dispersants were not used to stabilize the suspension, the solutions tested exhibited satisfactory stability. Ultrasonic vibration was used in order to stabilise the dispersion of the nanoparticles. Experimental measurements...
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Optimal placement of IMU sensor for the detection of children activity
PublikacjaIn this paper an investigation to determine the optimal placement of IMU sensors for the purpose of children characteristic activity detection is presented. The article compares four different placement of two IMU sensors on human body. Ten healthy volunteers participated within the study. Data were collected firstly from two wireless 9-axial IMU sensors placed at the left and right wrists, then sensors were placed at lower back...
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Modified linear viscoelastic model of earthquake-induced structural pounding
PublikacjaIn recent times, earthquake-induced structural pounding has been intensively studied through the use of different impact force models. The numerical results obtained from the previous studies indicate that the linear viscoelastic model is relatively simple and accurate in modeling pounding-involved behavior of structures during earthquakes. The only shortcoming of the model is a negative value of the pounding force occurring just...
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The experimental identification of the dynamic coefficients of two hydrodynamic journal bearings operating at constant rotational speed and under nonlinear conditions.
PublikacjaHydrodynamic bearings are commonly used in ship propulsion systems. Typically, they are calculated using numerical or experimental methods. This paper presents an experimental study through which it has been possible to estimate 24 dynamic coefficients of two hydrodynamic slide bearings operating under nonlinear conditions. During the investigation, bearing mass coefficients are identified by means of a newly developed algorithm....
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The Experimental Determination of Bearings Dynamic Coefficients in a Wide Range of Rotational Speeds, Taking into Account the Resonance and Hydrodynamic Instability
PublikacjaMethods for the experimental determination of dynamic coefficients are commonly used for the analysis of various types of bearings, including hydrodynamic, aerodynamic and foil bearings. There are currently several algorithms that allow estimating bearing dynamic coefficients. Such algorithms usually use various excitation techniques applied to rotor–bearings systems. So far only a small number of scientific publications show how...
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Application and optimization of headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography - flame-ionization detector (GC-FID) to determine products of the petroleum industry in aqueous samples
PublikacjaA simple and solvent-free analytical method has been optimized for the determination of hydrocarbons (C6 - C20) from products of the petroleum industry in aqueous samples. Extraction and analysis was carried out using headspace solid-phase microextraction (HS-SPME) and gas chromatography coupled with flame-ionization detector (GC-FID). A ZB-5 capillary column (30 m × 0.25 mm inner diameter, 0.25 µm film thickness) was used for...
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Pressure drop of HFE7000 and HFE7100 during flow condensation in minichannels
PublikacjaAttention is focused on the issues of flow resistance and pressure drop of perspective refrigeration fluids during condensation in the two-phase flow in minichannels. The case of the flow through a cylindrical single channel of 2.3 mm inner diameter was carefully analyzed. Pressure drop tests have been performed in diabatic flow conditions. The effect of heat flux, mass flux, vapour quality and saturation temperature on the two-phase...
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The optimization of CuxO microwires synthesis for improvement in photoelectrochemical performance
PublikacjaOne of the most important challenges in the fabrication of CuxO microstructures via the electrochemical method is formation of long, regular and well-packed microwires with good adhesion on the Cu substrate and to achieve better photoelectrochemical properties, which can be potentially applied in solar-driven water splitting and CO2 conversion to light hydrocarbons. In this paper, Cu2O photoelectrode has been fabricated by direct...
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Experimental examination and modification of chip suction system in circular sawing machine
PublikacjaThe article presents the results of experimental examination of the wood chip suction system in the existing sliding table saw before and after its modifi cation. The studies focused on the extraction hood of the mentioned system. The methodical experimental research of the pressure distribution inside the hood during wood chip removal for the selected rotational speed of saw blades of 3500 and 6000 min-1 with a diameter of 300...
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A concept for reducing PM 10 emissions for car brakes by 50%
PublikacjaWith regard to airborne particles with an aerodynamic diameter of less than 10 μm (PM10), in countries in the European Union, the mass of brake emissions equals approximately 8–27% of the total traffic-related emissions. Using a research methodology combining tests at different scale levels with contact mechanics simulations and PM10 chemical characterization, the REBRAKE EU-financed project had the following aims: i) to demonstrate...
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Compact Dual-Polarized Corrugated Horn Antenna for Satellite Communications
PublikacjaIn this paper, a structure and design procedure of a novel compact dual-polarized corrugated horn antenna with high gain and a stable phase center for satellite communication is presented. The antenna incorporates an Ortho-Mode Transducer (OMT), a mode converter, and a corrugated structure. The compact OMT section is designed to be fed by standard WR-75 waveguides. The proposed compact design utilizes only ten corrugated slots...
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Wpływ parametrów strugi paliwa wtryskiwanego do cylindra silnika okrętowego na początkową fazę rozpylania
PublikacjaPrzedmiotem rozprawy jest analiza procesu wtrysku oleju napędowego do cylindra silnika okrętowego z zapłonem samoczynnym i bezpośrednim wtryskiem paliwa. Analiza tego zagadnienia została przeprowadzona w aspekcie wpływu makro parametrów strugi na początkową fazę rozpylania oleju napędowego. Celem niniejszej pracy jest określenie wpływu współczynnika L/D (długość otworu/średnica) otworu wylotowego wtryskiwacza na zmianę charakterystyki...
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Selected studies of flow maldistribution in a minichannel plate heat exchanger
PublikacjaAnalysis of the state of-the-art in research of minichannel heat exchangers, especially on the topic of flow maldistribution in multiple channels, has been accomplished. Studies on minichannel plate heat exchanger with 51 parallel minichannels with four hydraulic diameters, i.e., 461 μm, 574 μm, 667 μm, and 750 μm have been presented. Flow at the instance of filling the microchannel with water at low flow rates has been visualized. The...
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approximation of photonic crystal fibres with large air holes by the step index fibre model
PublikacjaAn equivalent step index fibre with a silica core and air cladding is used to model photonic crystal fibres with large air holes. We model this fibre for linear polarisation (we focus on the lowest few transverse modes of the electromagnetic field). The equivalent step index radius is obtained by equating the lowest two eigenvalues of the model to those calculated numerically for the photonic crystal fibres. The step index parameters...
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Roof over PGE Arena in Gdansk. Review of structure and monitoring system
PublikacjaThis paper presents general structural assumptions of the steel construction designed for a newfootball stadium to be built for UEFA Championship 2012 in the city of Gdańsk. The superstructureis founded directly on the modified abutment. The facade and the roof are collected from 82 steelgirders made of tube profiles. The girders are braced by circular beams and X tension rods. All thiscreates a quasi - dome covered by polycarbonate...
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Modelling method for a class of distributed-lumped parameter systems
PublikacjaThe paper presents an alternative approach for modelling and order reduction of continuous system. The proposed methodology combines application of two methods: the modal decomposition method and the rigid finite element method. The given continuous structure is divided into 1D continuous substructures. For each 1D substructure modal decomposition and reduction procedure is applied. Interactions between substructures are described...
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Intelligent turbogenerator controller based on artifical neural network
PublikacjaThe paper presents a desing of an intelligent controller based on neural network (ICNN). The ICNN ensures at the same time two fundamental functions : the maintaining of generator voltage at the desired value and the damping of the electromechanical oscillations. Its performance is evaluted on a single machine infinite bus power system through computer simulations. The dynamic and transient operation of the proposed controller...
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Critical Remarks on Landauer’s principle of erasure– dissipation: Including notes on Maxwell demons and Szilard engines
PublikacjaWe briefly address Landauer’s Principle and some related issues in thermal demons. We show that an error-free Turing computer works in the zero-entropy limit, which proves Landauer’s derivation incorrect. To have a physical logic gate, memory or information-engine, a few essential components necessary for the operation of these devices are often neglected, such as various aspects of control, damping and the fluctuation–dissipation...
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Hybrid Reduced Model of Continuous System
PublikacjaThe paper introduces an alternative method of modelling and modal reduction of continuous systems. Presented method is a hybrid one. It combines the advantages of modal decomposition method and the rigid finite element method. In the proposed method continuous structure is divided into one-dimensional continuous elements. For each 1D element modal decomposition and reduction is applied. Interactions between substructures are...
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Experimental study on effectiveness of polymer dampers in reduction of structural vibrations
PublikacjaVibrations of civil engineering structures, generated by dynamic loads, may be very dangerous to the structures themselves as well as may have significant influence on human perception and comfort. A number of different methods have been proposed in order to minimize such situations. This concern newly designed structures as well as those which dynamic properties have to be modified due to problems with excessive vibrations. One...
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Linking of adjacent three-storey buildings for mitigation of structural pounding during earthquakes
PublikacjaThe reports after major earthquakes indicate that the earthquake-induced pounding between insufficiently separated buildings may lead to significant damage or even total collapse of structures. An intensive study has recently been carried out on mitigation of pounding hazards so as to minimize the structural damages or prevent collisions at all. The aim of this paper is to investigate the effectiveness of the method when two adjacent...
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Experimental study on the effectiveness of polymer dampers in reduction of structural vibrations
PublikacjaVibrations of civil engineering structures, generated by dynamic loads, may be very dangerous to the structures themselves as well as may have significant influence on human perception and comfort. A number of different methods have been proposed in order to minimize such situations. This concern newly designed structures as well as those which dynamic properties have to be modified due to problems with excessive vibrations. One...
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Mitigating the seismic pounding of multi-story buildings in series using linear and nonlinear fluid viscous dampers
PublikacjaSeismic-induced pounding between adjacent buildings may have serious consequences, ranging from minor damage up to total collapse. Therefore, researchers try to mitigate the pounding problem using different methods, such as coupling the adjacent buildings with stiff beams, connecting them by using viscoelastic links, and installing damping devices in each building individually. In the current paper, the effect of using linear and...
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Investigation method of large-volume tire with mobile test rig
PublikacjaThe goal of this research is to develop the tire test method and mobile tire test rig. The test rig enables measurement of tire properties as stiffness and viscous damping in vertical direction, and tire–ground characteristics on the asphalt rigid surface. The tire-ground characteristics are measured by force and a torque measurement hub. The design, calibration and the algorithm for calculating the forces in the wheel center are...
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Deposition of phosphate coatings on titanium within scaffold structure
PublikacjaPurpose: Existing knowledge about the appearance, thickness, and chemical composition of phosphate coatings on titanium inside porous structures is insufficient. Such knowledge is important for the design and fabrication of porous implants. Methods: Metallic scaffolds were fabricated by selective laser melting of 316L stainless steel powder. Phosphate coatings were deposited on Ti sensors placed either outside the scaffolds or...
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Suitableness of SLM Manufactured Turbine Blade for Aerodynamical Tests
PublikacjasettingsOrder Article Reprints Open AccessArticle Suitableness of SLM Manufactured Turbine Blade for Aerodynamical Tests by Janusz Telega 1,*ORCID,Piotr Kaczynski 1ORCID,Małgorzata A. Śmiałek 2ORCID,Piotr Pawlowski 3ORCID andRyszard Szwaba 1ORCID 1 Institute of Fluid Flow Machinery Polish Academy of Sciences (IMP PAN), Fiszera 14, 80-231 Gdansk, Poland 2 Faculty of Mechanical Engineering and Ship Technology, Institute of Naval...
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Designing control strategies of aeration system in biological WWTP
PublikacjaThe paper presents the complete design processes of a novel aeration control systems in the SBR (Sequencing Batch Reactor) wastewater treatment plant (WWTP). Due to large energy expense and high influence on biological processes, the aeration system plays a key role in WWTP operation. The paper considers the aeration system for a biological WWTP located in the northeast of Poland. This system consists of blowers, the main collector...
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GaN Nanowire Array for Charge Transfer in Hybrid GaN/P3HT:PC71BM Photovoltaic Heterostructure Fabricated on Silicon
PublikacjaAbstract: We demonstrate that a GaN nanowire array can be used for efficient charge transfer between the organic photovoltaic layer and silicon in a Si/GaN/P3HT:PC71BM inverted hybrid heterostructure. The band alignment of such a material combination is favorable to facilitate exciton dissociation, carrier separation and electron transport into Si. The ordered nature of the GaN array helps to mitigate the intrinsic performance...
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Deep neural network architecture search using network morphism
PublikacjaThe paper presents the results of the research on neural architecture search (NAS) algorithm. We utilized the hill climbing algorithm to search for well-performing structures of deep convolutional neural network. Moreover, we used the function preserving transformations which enabled the effective operation of the algorithm in a short period of time. The network obtained with the advantage of NAS was validated on skin lesion classification...
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Human Centric Lighting. The New X Factor?
PublikacjaWe live in challenging times, and one could even claim we’re experiencing a revolution in lighting with LED technology taking over the world. Part of this rapid change involves a concept called Human Centric Lighting (HCL). In Frankfurt this year, during Light+Building, it was the buzzword, with nearly every second manufacturer’s stand claiming they had figured out the special formula necessary to create perfect HCL illumination....
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Broker telekomunikacyjny
PublikacjaDemonopolizacja rynku usług telekomunikacyjnych narzuca konieczność realizacji funkcji wyboru operatora sieci dla obsługi żądania usługi. W pracy przedstawiono koncepcję, realizację oraz wyniki testów i badań Brokera Telekomunikacyjnego BT, który realizuje tą funkcję. Algorytm podejmowania decyzji przez BT uwzględnia parametry poziomu i jakości usług oferowane przez operatorów oraz preferencje klienta dotyczące połączenia. Klient...
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Nano-structured Pt embedded in acidic salts of heteropolymolybdate matrices: MS EXAFS study
PublikacjaA structural study of Pt nano-catalysts is presented in the paper. The innovation in the case of the considered catalytic materials resides in the use a meso-microporous inorganic matrix of heteropolyacid salt of composition X2.5H0.5YMo12O40 where X = Rb, Cs and Y = P, Si as a catalyst support. Metallic nanoparticles were created by platinum ions reduction in a hot H2/Argon stream and were mainly located into matrix pores. As the...
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Deterministic rendezvous of asynchronous bounded-memory agents in polygonal terrains
PublikacjaTwo mobile agents, modeled as points starting at differentlocations of an unknown terrain, have to meet. The terrain is a polygon with polygonal holes. We consider two versions of this rendezvous problem: exact RV, when the points representing the agents have to coincide at some time, and epsilon-RV, when these points have to get at distance less than epsilon in the terrain. In any terrain, each agent chooses its trajectory, but...
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Parity vertex colouring of graphs
PublikacjaA parity path in a vertex colouring of a graph is a path along which each colour is used an even number of times. Let Xp(G) be the least number of colours in a proper vertex colouring of G having no parity path. It is proved that for any graph G we have the following tight bounds X(G) <= Xp(G) <=|V(G)|− a(G)+1, where X(G) and a(G) are the chromatic number and the independence number of G, respectively. The bounds are improved for...
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Properties of ordered titanium templates covered with Au thin films for SERS applications
PublikacjatCurrently, roughened metal nanostructures are widely studied as highly sensitive Raman scattering sub-strates that show application potential in biochemistry, food safety or medical diagnostic. In this workthe structural properties and the enhancement effect due to surface enhanced Raman scattering (SERS) ofhighly ordered nano-patterned titanium templates covered with thin (5–20 nm) gold films are reported.The templates are formed...
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Experimental Studies of Concrete-Filled Composite Tubes under Axial Short- and Long-Term Loads
PublikacjaThe paper presents experimental studies on axially compressed columns made of concrete-filled glass fiber reinforced polymer (GFRP) tubes. The infill concrete was C30/37 according to Eurocode 2. The investigated composite pipes were characterized by different angles of fiber winding in relation to the longitudinal axis of the element: 20, 55 and 85 degrees. Columns of two lengths, 0.4 m and 2.0 m, were studied. The internal diameter...
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Assessment of the impact of jet impingement technique on the energy efficiency of air-cooled BIPV/T roof tile
PublikacjaThe paper concerns a numerical analysis of cooling of the hybrid photovoltaic (PV) modules dedicated to Building-Integrated Photovoltaic/Thermal (BIPV/T) systems. Attention was focused on the photovoltaic roof tiles, using a jet impingement technique, in which the intensification of heat transfer is ensured by streams of air hitting the heat exchange partition. A series of numerical simulations were carried out to assess an influence...
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The impact of natural fibers’ characteristics on mechanical properties of the cement composites
PublikacjaThe paper reviews the properties of cement composites reinforced with short fibres. The effect of natural fibres was investigated: cotton, sisal, jute, ramie, bamboo, and synthetic fibres: polymer and polypropylene. It was noticed that the fibres change the consistency of the mixture up to 15%. In the composite flexural strength tests, a change in strength by +/− 8% was observed, depending on the type of fibres used. The research...