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COMPOSITE MATERIAL SELECTION FOR A PATIENT TRANSFER ASSIST DEVICE
PublikacjaLaminates - layered composites containing at least two elements (matrix and reinforcement) widely used in industry have also found their usage in medicine. Their main feature is the ability to modify the material in order to obtain the required properties. Depending on the needs, we can modify reinforcement, type of resin or the method of bonding substrates. Commonly used fibers are: carbon fiber, glass and aramid fibers; resins...
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Alternative way of the main reinforcement anchorage in reinforced short cantilevers
PublikacjaThe results of the experimental investigation of the reinforced corbels and dapped end beams with steel studs were introduced in the work. The efficiency of this type of the reinforcement was compared with the typical reinforcenet applied in reinforced conctrete construcions.
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Investigation and operation problems of metal tanks in Poland
PublikacjaThe paper consists of three parts concerned with steel cylindrical, vertical tank for liquid fuel. In the first part the present trends in tank design and building in Poland are described. The main are: · reduction of environment contamination danger caused by tank leakage and hydrocarbons evaporation, · increasing capacity of new tanks (100000 m3 and more) due to economic factor - reduction of steel amount per m3 of storage capacity....
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Protective and Suppressing Electromagnetic Interference Properties of Epoxy Coatings Containing Nano-Sized NiZn Ferrites
PublikacjaNano-crystalline ferrites with the chemical formula NixZn(1−x)Fe2O4, where x = 0, 0.2, 0.4, 0.6, 0.8, 1.0, were synthesized using a co-precipitation method. The obtained ferrites were investigated by X-ray diffraction (XRD). The corrosion inhibiting behavior of nano-sized ferrites was tested using carbon steel samples and 10% aqueous ferrite extracts. Results were compared with previous data obtained for micro-sized ceramic ferrites....
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Wybrane aspekty modelowania uderzenia pojazdem dźwigara wiaduktu
PublikacjaW pracy przedstawiono różne zagadnienia związane z uderzeniem pojazdu w dźwigar wiaduktu. Omówiono wybór modelu obliczeniowego, na podstawie porównania wyników dla modelu dźwigara zespolonego, modelu dźwigara stalowego oraz modelu wiaduktu. Następnie opisano model dźwigara zespolonego zastosowany w analizie MES oraz metodę wyznaczania współczynników tłumienia Rayleigha. Symulację numeryczną uderzenia dźwigara wiaduktu przez koparkę...
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PRĄDY WYRÓWNAWCZE W UZIOMACH FUNDAMENTOWYCH I SZTUCZNYCH
PublikacjaW artykule omówiono zasady wykonywania uziomów fundamentowych i sztucznych. Przedstawiono wyniki pomiarów prądów w instalacji zawierającej stal zbrojeniową w fundamencie, połączoną z układem uziomu sztucznego w ziemi wykonanym z stali ocynkowanej.
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TRUSS JOINT WITH POSITIVE ECCENTRICITY EXPERIMENTAL RESEARCH
PublikacjaDue to the technological reasons in modern lightweight steel trusses, fabricated from cold- formed sections, positive eccentricities appear in the truss nodes what induce additional forces in the truss chords. To account for the real load-carrying capacity of truss node area the steel structure research in scale 1:1 were conducted. The experiments consisted of two parts: preliminary and proper one, when conclusions from...
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Investigation of behaviour of metal structures with polymer dampers under dynamic loads
PublikacjaA large number of accidents concerning structures subjected to dynamic loads have been recently observed. One of the examples of such a structure is a temporary steel grandstand erected using scaffolding system. Dynamic load that is generated by crowd movement has a significant influence on the behaviour of the structure and may lead to excessive structural vibrations. The aim of the study is to consider the idea of using polymer...
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Corrosion monitoring by harmonic analysis in aqueous environments
PublikacjaThis paper presents tests concerning the rate of corrosion in non-alloy steel (type S235JR) in an aqueous environment, with an additive of sodium chloride by means of polarization resistance measurements and harmonic analysis. The tests have been carried out for steel samples exposed to the testing environment for six weeks, in order to obtain a constant rate of corrosion in the function of time. The measurements have aimed at...
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INFLUENCE OF SOLID PARTICLE CONTAMINATION ON THE WEAR PROCESS IN WATER LUBRICATED MARINE STRUT BEARINGS WITH NBR AND PTFE BUSHES
PublikacjaThis paper reports on a study of the influence of solid particle contamination on the wear process in water-lubricated slide bearings (steel-acrylonitrile-butadiene rubber (NBR) and steel- polytetrafluoroethylene (PTFE)). To compare the wear of the shaft journal and bushes (NBR and PTFE) when lubricated with fresh water and contaminated water, an experiment was carried out to identify key factors that influence the state of wear...
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Tribological Properties of Thermoplastic Materials Formed by 3D Printing by FDM Process
PublikacjaThe dataset entitled 3D printed ABS thermoplastic vs. steel. Dry sliding wear test in constant load & velocity ring on flat configuration. Test parameters: print layer thickness and orientation. Test symbol: 019_h_4 contains: the time base (expressed in seconds and minutes), the friction torque for sliding friction, rotational velocity of the counter – specimen (velocity of sliding), friction coefficient, load in the friction contact...
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On the correlation between magnetoacoustic emission and magnetostriction dependence on the applied magnetic field
PublikacjaThe correlation between magnetoacoustic emission signal envelopes and magnetostriction curves is investigated. Two sets of samples are being considered: tempered martensitic steel and plastically deformed ferritic steel. It is shown that even though some general relations may be observed, as was demonstrated in the literature, the correlation is not always present. One may not expect to change both quantities in the same way if...
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Study on Microstructural Characterization, Mechanical Properties and Residual Stress of GTAW Dissimilar Joints of P91 and P22 Steels
PublikacjaThis article deals with the dissimilar joining of two different grade Cr-Mo steel (2.25Cr-1Mo: P22 and modified 9Cr-1Mo: P91) for power plant application. The dissimilar butt-welded joint was produced for conventional V groove design by using the gas tungsten arc welding (GTAW) process with the application of an ERNiCrMo-3 Ni-based super alloy filler. A microstructure characterization was performed to measure the inhomogeneity...
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Recovery and re-use of photovoltaic solar cells from crystalline silicon
PublikacjaCrystalline silicon-type PV modules consist, in order of mass, of glass, an aluminium frame, an EVA coating, solar cells, a terminal box, back film and tapping screws. From the economic point of view, pure silicon, recoverable from spent cells, is the most important material owing to its cost and shortage. For crystalline, silicon-based PV cells, the following chemical treatments were performed: removal of the metal coating, followed...
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Potential of Functionalized Polyolefins in a Sustainable Polymer Economy: Synthetic Strategies and Applications
PublikacjaPolymers play a crucial role in our modern life as no other material exists that is so versatile, moldable, and lightweight. Consequently, the demand for polymers will continue to grow with the human population, modernization, and technological developments. However, depleted fossil resources, increasing plastic waste production, ocean pollution, and related growing emission of greenhouse gases has led to a change in the way we...
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Is the Concept of Zero Waste Possible to Implement in Construction?
PublikacjaThe scientifically treated problem of reusing building materials appeared in the literature more than 50 years ago. This paper includes an analysis of the characteristics of recycled building materials, which is a prerequisite for rational recycling. The analysis and simulation of building stocks at different scales has led to the conclusion that the most important link in the transformation of the construction industry towards...
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Recovery of silver metallization from damaged silicon cells
PublikacjaMetallization is one of the key process steps to fabricate solar cells with high performance in a cost-effective way. Majority of photovoltaic solar cell manufacturing uses thick film screen print metallization with Ag containing paste to produce solar cells. The average lifetime of PV modules can be expected to be more than 25 years. The disposal of PV systems will become a problem in view of the continually increasing production...
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Corrosion behavior of concrete produced with diatomite and zeolite exposed to chlorides
PublikacjaChloride induced reinforcement corrosion is widely accepted to be the most frequent mechanism causing premature degradation of reinforced concrete structures. The electrochemical impedance of reinforcing steel in diatomite- and zeolite-containing concrete exposed to sodium chloride was assessed. Chemical, physical and mineralogical properties of three concrete samples (20% diatomite, 20% zeolite, and a reference containing neither)...
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Surface Texture after Turning for Various Workpiece Rigidities
PublikacjaIn the paper, we present an analysis of the surface texture of turned parts with L/D (length/diameter) ratios of 6 and 12 and various rigidity values. The studies were carried out on samples made of S355JR steel and AISI 304 stainless steel. A detailed analysis of 2D surface profiles was carried out by using a large number of parameters that allowed us to distinguish significant differences in the surface microgeometry, which confirmed...
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Effect of electrode waterproof coating on quality of underwater wet welded joints
PublikacjaIn this paper, the effects of different hydrophobic coatings on the surface of covered electrodes on the quality of wet welded carbon steel joints were discussed. Commonly available hydrophobic substances used in industrial applications were selected for the research. The aim of using waterproof coatings was to check the possibility to decreasing the susceptibility of highstrength low-alloy S460N steel to cold cracking. During...
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INFLUENCE OF TACK WELDS DISTRIBUTION AND WELDING SEQUENCE ON THE ANGULAR DISTORTION OF TIG WELDED JOINT
PublikacjaIn this paper the influence of tack welds distribution and welding sequence on angular distortion of the Tungsten Inert Gas (TIG) welded joint was tested. Additionally, the effect of welding current on angular distortion was assessed. For research X2CrTiNb18 (AISI 441) stainless steel (2.5 mm thick) was chosen. During research specimens were prepared with different distributionsof tack...
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Ship’s de-perming process using coils lying on seabed
PublikacjaA ship built from ferromagnetic steel disturbs the uniformity of the Earth’s magnetic field. Changes of ship’s signature are due to the magneto-mechanical interaction of the hull with the Earth’s magnetic field. The ship’s magnetic field can be detected by a magnetic naval mine. For this reason, the vessel has to be demagnetized. There are several methods of ship’s de-perming. The results of experimental and computer simulations...
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Reference-free determination of debonding length in reinforced concrete beams using guided wave propagation
PublikacjaThis paper presents theoretical and experimental investigations of guided wave propagation in reinforced concrete beams, with pre-existing debonding between steel rebars and concrete blocks, for the purpose of damage detection. The primary aim of these investigations was a detailed analysis of the possible applications of wave propagation in single and multiple debonding detection in reinforced concrete structures and reference-free...
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Numerical investigation of the core eccentricity effect on wave propagation in embedded waveguide
PublikacjaThe paper presents results of theoretical and numerical investigation of guided wave propagation in two-layer bars with geometric imperfections in the form of eccentric location of steel core. Steel rod of diameter equal to 1 cm embedded in composite mortar-type cover with external diameter equal to 5 cm has been taken into consideration. Several different rods with variable size of eccentricity are analysed. Results for rods with...
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Repeated Projectile Impact Tests on Multi-Layered FibrousCementitious Composites
PublikacjaThis research aims to experimentally evaluate the behaviour of multi-layered fibrous cementitious composites withintermediate Glass Fibre Meshes (GFM) under repeated projectile load. The impact load was subjected through a convexedge projectile needle at a low velocity on cylindrical specimens of three-layered fibrous cementitious composites, whichhave two different steel fibre distributions. In series A mixtures, a constant steel...
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Building damage due to structural pounding during earthquakes
PublikacjaEarthquake-induced pounding between adjacent buildings has been identified as one of the reasons for substantial damage or even total collapse of colliding structures. A major reason leading to interactions in buildings results from the differences in their dynamic parameters and also from insufficient distance between the structures. Although the research on structural pounding has been much advanced, the studies have mainly been...
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Mechanical Properties of 3D Printed Parts and Their Injection Molded Alternatives Subjected to Environmental Aging
PublikacjaAdditive manufacturing is the technology used in medical, industrial, or lifestyle applications. The scientific literature include works reporting various manufacturing parameters’ influence on changes in additive manufacturing components’ mechanical behavior, especially with fused filament fabrication (FFF). The changes in mechanical strength and toughness of FFF compared to injection molding parts were studied. In the study,...
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The Impact of Hybrid Flame Retardant Compositions on the Performance of Foamed Flexible Polyurethane/Ground Tire Rubber Composites
PublikacjaCurrent sustainability-oriented trends affect polyurethane (PU) materials and stimulate the incorporation of recycled or waste-based materials as fillers. Ground tire rubber (GTR) poses as an auspicious candidate due to the excellent performance of car tires. Despite the benefits related to the mechanical performance, it contributes to the increasing flammability of the resulting composites. Herein, presented work assessed the...
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Recycling of Waste Rubber by Thermo-Mechanical Treatment in a Twin-Screw Extruder
PublikacjaRecycling of waste tires is a significant issue considering both environmental and economic aspects. One of the leading recycling routes is the shredding of tires resulting in the generation of ground tire rubber. This material can be easily introduced into various polymer matrices as a filler, reducing the use of conventionally applied petroleum-based materials. In such cases, it is essential to ensure sufficient interfacial compatibility,...
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Ground anchors diagnostic process based on elastic wave propagation method
PublikacjaThe paper is focused on analysis of elastic wave propagation in the context of diagnostics of ground anchors. Numerical simulations were performed to assess the possibility of evaluation of the anchorage quality. It was assumed that the quality and the load capacity of the anchor system directly depend on the length, on which mortar and steel cooperate.
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Computer support of analysis optical spectra measurements
PublikacjaVerification of measurement errors has a big impact on assessment of accuracy of conducted measurements and obtained results. In many cases computer simulation results are compared with measurement results in order to evaluate measurement errors. The purpose of our research was to check the accuracy of measurements made with Fabry-Perot interferometer working in the transmission mode. In measurement setup, a 1310 nm superluminescent...
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Detection of Delamination in Laminate Wind Turbine Blades Using One-Dimensional Wavelet Analysis of Modal Responses
PublikacjaThis paper demonstrates the effectiveness of a nondestructive diagnostic technique used to determine the location and size of delamination in laminated coatings of wind turbine blades. This is realized based on results of numerical and experimental investigations obtained by the use of the finite element method (FEM) and laser scanning vibrometry (LSV). The proposed method is based on the one-dimensional continuous wavelet transform...
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The Application of Cluster Analysis in the Assessment of the Weldability of Unalloyed Steels
PublikacjaNon-alloy steels constitute a large group of steels characterised by diversified chemical composition, structural morphology and a wide range of mechanical properties (determining weldability). The paper presents results of multidimensional analyses (based on cluster analysis) of 110 selected unalloyed steel grades. Properties adopted as diagnostic features included the chemical composition, mechanical properties (yield point)...
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Risks caused by microbiologically influenced corrosion in diesel fuel storage tanks
PublikacjaMicrobiologically influenced corrosion (MIC) poses serious problems for the petrochemical and refinery industries. Particularly favourable conditions for MIC arise in storage tanks and transmission pipelines for mixtures of diesel oil with the addition of a biocomponent (in Poland 7%). The best conditions for the development of MIC occur at the fuel-water interface, where microorganisms are provided with a source of food and water,...
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Influence of the Widespread Use of Corten Plate on the Acoustics of the European Solidarity Centre Building in Gdansk
PublikacjaThis paper describes the relationship between a strong architectural vision that is difficult to balance, and user expectations in terms of acoustics. The focus is on the use of corten steel as the dominant finishing material on façades and interiors to achieve an expressive, symbolic message through program-based design. The architectural premises justifying the adopted solutions are presented, especially the universality and...
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Novel application of dynamic electrochemical impedance monitoring to a cataphoretic coating process
PublikacjaThe paper presents a novel method of on-line impedance monitoring of cataphoretic coating application process. Utilization of dynamic electrochemical impedance spectroscopy (DEIS) overcame the fundamental problem connected with non-stationarity of the aforementioned coating deposition process, which eliminates classical impedance spectroscopy technique from a real-time description of cataphoresis. The paper illustrates selected examples...
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The Influence of Selected Parameters of Numerical Modelling on Strains and Stresses at Weld Toe Notch
PublikacjaLatest development in the field of welding technology and prefabrication enabled massive production of thin-walled sandwich structures. Multi-layered sandwich structures are fabricated with the use of high-power CO2 lasers, friction welding, arc welding, hybrid welding, or other technique designed for the special purpose. Steel or aluminium alloy plates with thickness between 1 and 5 mm are connected by internal stiffeners. Strength...
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Burnout Investigation of Small Diameter Tubes Immersed in Nanofluids
PublikacjaThis paper deals with research into pool boiling critical heat flux (CHF) of water–Al2O3, water–TiO2 and water–Cu nanofluids on horizontal stainless steel tubes. The experiments were conducted under atmospheric pressure. Nanoparticles were tested at concentrations of 0.001%, 0.01%, 0.1% and 1% by weight. Ultrasonic vibration was used in order to stabilize the dispersion of the nanoparticles. Although dispersants were not used to...
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Manganese Phosphatizing Coatings: The Effects of Preparation Conditions on Surface Properties
PublikacjaManganese phosphate coating could be used to protect the surface of steel products. However, it is essential to determine the effects which process parameters, as well as the types of additives used, have on the efficiency of coating deposition. Thus, we present here a process of phosphatization of low-alloy steel (for 15 min at 95 ◦C) in manganese/nickel baths followed by a passivation process with the use of a silicon and zircon...
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Buckling Analysis of Cold Formed Silo Column
PublikacjaThe paper is devoted to stability analysis of different models of steel cold formed silo column. The steel cylindrical silos are often composed of corrugated walls and vertical open-sectional columns uniformly placed along the silo circumference. Both the whole 3D silo, a simplified model consisting of one column with a part of the silo walls, and a single column resting on elastic foundation provided by the silo walls were analyzed....
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Ocena stanu technicznego rurociągu przesyłowego zawiesiny popiołów w Elektrowni Ostrołęka B
PublikacjaPrzedmiotem pracy był rurociąg przesyłowy zawiesiny popiołów przesyłanych z Elektrowni Ostrołęka B. Celem pracy było potwierdzenie przynależności próbek yvyciętych z rurociągu do określonego gatunku stali i ocena stanu materiału po eksploatacji. Dla zrealizowania tego celu wykonano: - analizę składu chemicznego materiału pobranego ze stalowych rur, - mikroanalizę warstw wierzchnich na powierzchni wewnętrznej i zewnętrznej, -...
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Badania nośności na zginanie innowacyjnego kształtownika giętego na zimno typu GEB
PublikacjaLekkie konstrukcje metalowe wytwarzane z kształtowników giętych na zimno to jedna z najszybciej rozwijających się dyscyplin w zakresie budownictwa. Do niedawna profile gięte na zimno stosowano wyłącznie jako elementy drugorzędne, czyli płatwie oraz rygle. Nowo opatentowany przekrój typu GEB ma być wykorzystywany jako element nośny konstrukcji ramowych. Jednak jego zaistnienie na rynku budowlanych konstrukcji metalowych jest uwarunkowane...
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Carbon dioxide sequestration by industrial wastes through mineral carbonation: Current status and perspectives
PublikacjaMineral carbonation using natural minerals or industrial wastes is a safe and promising strategy for CO2 sequestration. Application of industrial wastes for this purpose has significant ecological and environmental value, which is one of the key green technologies in the global carbon mitigation. This review summarizes the current research status of CO2 mineralization by industrial wastes. This work surveys the mechanisms and capacities...
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Standard and modified falling mass impact tests on preplaced aggregatefibrous concrete and slurry infiltrated fibrous concrete
PublikacjaAlthough several studies have been conducted to evaluate the impact response of concrete using theAmerican Concrete Institute (ACI) 544-2R falling mass impact test, the variations in test results are themain drawback of this testing method. This study aims to reduce the variations in experimental impacttest results by introducing two simple test setup modifications; (1) using coarse or fine aggregate bed-ding as an alternative...
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The correlation of fractal dimension to fracture surface slope for fatigue crack initiation analysis under bending-torsion loading in high-strength steels
PublikacjaIn this study, the fractal dimension of fatigue fracture surfaces is investigated in order to find an alternative failure loading indicator. Some of many metrological factors are generalized by reducing the fracture surface structure to one factor and develop an entire fracture surface procedure by analyzing the impact of surface slope and calculation resolution. Three notched geometries are studied under cyclic bending-torsion:...
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Multiparameter sensitivity analysis of a GFRP composite footbridge of a sandwich structure and U-shaped cross-section
PublikacjaThe paper deals with multiparameter sensitivity analysis of a composite footbridge. A shell‐like structure is 14.5 m long shows U‐shaped cross‐section and inner service dimensions 1.3 × 2.5 m. Glass fiber reinforced polymer GFRP laminate constitutes faces of a sandwich structure while PET foam received from recycled bottle builts a core. The structure was divided into 285 independent areas where the thickness of laminates and stiffness...
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The concept of sewage-sludge management system for an individual household
PublikacjaThe individual farms at the rural areas often face problems with domestic sewage collection and treatment. In many cases building of sewerage systems and central wastewater treatment plants (WWTPs) brings too high costs, due to high distances from one farm to another and terrain configuration. Treatment wetlands for individual farms can solve this problem. In the article, an overview of individual treatment wetlands in Europe and...
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Poroelastic Road Surface – a Promising Road Traffic Noise Abatement Solution
PublikacjaRoad surfaces have a direct impact on the generation of noise by rolling tyres, the main and dominant source of noise of moving vehicles, as well as may affect propagation of noise emitted by all noise sources of a vehicle. Thus there is no doubt that pavement should be considered as one of the major potential road traffic noise abatement measure. Low noise pavements of existing types may in new conditions provide up to 8 dB of...
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The Influence of Modelling Material Zones on Strains and Stresses at Weld Toe Notch
PublikacjaThe latest development in the field of welding technology enabled prefabrication of thin-walled sandwich structures in an industrial scale. Sandwich structures fabricated of steel, or aluminium alloy plates and stiffeners are welded with the use of hi-power CO2 lasers. Strength analysis of such structures with the use of finite element method needs proper material modelling.In this paper the material model of steel sandwich panel...
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Evaluation of reformer tubes degradation after long term operation
PublikacjaPurpose of this paper is to show the effect of long-term service at elevated temperatures on microstructural changes of cast steel reformer tubes made of the alloy IN-519 (24%Cr, 24%Ni, Nb). The relationship between mechanical properties and microstructure degradation is discussed. Investigations were performed on five tubes taken from ammonia reformer furnace. Tubes worked at temperature of 880C and 3,2 MPa pressure. The operation...