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Synthesis and properties of AxV2Al20 (A = Th, U, Np, Pu) ternary actinide aluminides
PublicationPolycrystalline samples of AxV2Al20 (A = Ce, Th, U, Np, Pu; 0.7 ≤ x ≤ 1.0) actinide intermetallics were synthesized using the arc-melting method. Crystal structure studies were performed by means of powder x-ray diffraction and the Rietveld refinement method. All studied compounds crystallize in the CeCr2Al20-type structure (space group Fd-3m, no. 227) with the actinoid and Ce atom located in the oversized icosahedral cage formed...
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Searching for innovation knowledge: insight into KIBS companies
PublicationThe paper analyses the activity of research for “innovation knowledge”—here defined as knowledge that can lead to the introduction of service innovations—by Knowledge-Intensive Business Services (KIBS) companies. It proposes a classification of the possible search approaches adopted by those companies based on two dimensions: the pro-activity of search efforts and the source primarily used. Such classification is then discussed...
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Water absorption and blistering of glass fibre-reinforced polymer marine laminates with nanoparticle-modified coatings
PublicationMacro and microstructural damage was studied in typical glass fibre-reinforced polymer laminates with two types of coating systems – (a) isophtalic gel coat: pure or mixed with SiO2 nanoparticles 5 wt% (5%N) or 10 wt% (10%N) and (b) a two-layer coating system: urethane-modified vinyl ester-based gel coat and additional polyester barrier coat layer. Accelerated tests were performed at 50C for 50 days for specimens with nanoparticle-modified...
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Materials Design for the Titanium Scaffold Based Implant
PublicationThe main objective of here presented research is a design the scaffold/porous titanium(Ti) alloy based composite material demonstrating better biocompatibility, longer lifetime andbioactivity behaviour for load-bearing implants. The development of such material is proposed bymaking a number of consecutive tasks. Modelling the mechanical, biomechanical and biologicalbehavior of porous titanium structure and an elaboration of results...
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Perfect thermal contact of hyperbolic conduction semispaces with an interfacial heat source
PublicationThe problem of thermal contact between two bodies with a heat source at their interface presents great scientific and practical interest. On the time scale of a nanosecond or shorter, heat propagation should be considered in the form of thermal waves of finite speeds. This study investigated the thermal behaviour of hyperbolic conduction semispaces in perfect thermal contact subjected to the action of an interfacial heat source....
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Thermal visualization of Ostwald-de Waele liquid in wavy trapezoidal cavity: Effect of undulation and amplitude
PublicationThe present study is concerned with the numerical simulations of Ostwald-de Waele fluid flow in a wavy trapezoidal cavity in the presence of a heated cylinder situated at the center of the cavity. The work consists in characterizing the mixed convection as a function of the intensity of heat flow. The flow behaviour and temperature distribution in a cavity are the main focus of this study. The lower wall of the cavity is fixed...
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End-of-life management of single-use baby diapers: Analysis of technical, health and environment aspects
PublicationSingle-use baby diapers belongs to an important group of products used in the parenting journey because of their high performance and convenience. Single-use baby diapers are normally thrown away after one-time use, resulting in a waste management problem. The goal of this paper was to better understand main environmental concerns of different types of diapers and address how to reduce them, with a special consideration of waste...
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Nonlinear Fuzzy Control System for Dissolved Oxygen with Aeration System in Sequencing Batch Reactor
PublicationBiological processes at a wastewater treatment plant are complex, multivariable, time varying and nonlinear. Moreover, interactions between the components are very strong. Control of dissolved oxygen is one of most important task at the plant. The level of dissolved oxygen in aerobic tanks has significant influence on behaviour and activity of microorganisms at the plant. Air for aerated tanks is supplied by the aeration system...
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Application of chiral chromatography for enantiomeric separation of currently used pesticides from various chemical groups
PublicationChiral pesticides account for more than 25 % of currently used pesticides and this ratio is still increasing. According to the number of chiral centers in the structure, a pesticide may consist of two or multiple enantiomers or stereoisomers. Studies into the stereoselective behaviour of pesticides started in the early 1990s and most research efforts focused on understanding the environmental fate and effects of these pesticides....
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Influence of microwave treatment conditions of GTR on physico-mechanical and structural properties of NBR/NR/GTR composites
PublicationThe increasing amount of tires used in the industry induces the researchers to find alternatives to the recycling of the end-of-life tires. Several alternatives in order to application of ground tire rubber GTR include their incorporation as a filler in composites. The main issue in this approach is the lack of compatibility between GTR and polymer matrix. In order to solve this problem the devulcanization by microwaves has been...
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In-situ odd random phase electrochemical impedance spectroscopy study on the electropolymerization of pyrrole on iron in the presence of sodium salicylate – The influence of the monomer concentration
PublicationIn this work, the potentiostatic electropolymerization of polypyrrole (PPy) on iron in aqueous solution of sodium salicylate and pyrrole is studied in situ by odd random phase electrochemical impedance spectroscopy (ORP-EIS). The influence of the pyrrole concentration on the electrosynthesis process is investigated. The ORP-EIS technique ensures a reliable analysis of the PPy electrosynthesis on iron by means of an advanced data...
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The effectiveness of polymer adhesive in reduction of vibrations of structural members
PublicationIn this paper, the idea of using polymer adhesive as a damping layer is proposed. An experimental study of two aluminium cantilevered beams has been conducted. One of them presents a plain cantilevered beam, while the second one considers two aluminium beams bonded with a polymer adhesive of different thickness (0,5; 1,2; 1,75; 3,1 and 5 mm). The polymer adhesive considered in the study is a specially designed flexible...
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Influence of Selected Warm Mix Asphalt Additives on Cracking Susceptibility of Asphalt Mixtures
PublicationWarm mix asphalt (WMA) has been widely accepted as a future asphalt paving technology. Besides clear advantages, there are still some concerns regarding durability and long-term performance of pavements made with this type of asphalt mixtures. One of the most important issues is low temperature behaviour of WMA because certain additives used for temperature reduction can aect bitumen properties. This paper presents the evaluation...
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Civil liability for artificial intelligence products versus the sustainable development of CEECs: which institutions matter?
PublicationThe aim of this paper is to conduct a meta-analysis of the EU and CEECs civil liability institutions in order to find out if they are ready for the Artificial Intelligence (AI) race. Particular focus is placed on ascertaining whether civil liability institutions such as the Product Liability Directive (EU) or civil codes (CEECs) will protect consumers and entrepreneurs, as well as ensure undistorted competition. In line with the...
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Dynamic analysis of the railway bridge span under moving loads
PublicationThe first part of this paper provides a review of the state of knowledge of the dynamic behaviour of railway bridges under moving loads. Particular attention is paid to developments in modelling railway bridge loading and dynamic vehicle-span (structure) interaction. The most important aspects determining the advancements in this area of knowledge are identified. The contemporary techniques for defining bridge span finite element...
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Increasing the Seismic Resistance of Wood-frame Buildings by Applying PU Foam as Thermal Insulation
PublicationWood-frame buildings are very common in regions that are exposed to earthquakes. Most of residential buildings are constructed using this technology; therefore, the seismic resistance of them is really essential in order to prevent human losses and structural damage. The aim of the present article is to show the results of the detailed numerical FEM analysis focused on the seismic behaviour of the wood-frame house with different...
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Contribution to the mechanism of liquid membrane oscillators involving cationic surfactant.
PublicationIt is shown that liquid membrane oscillators with cationic surfactants havemore complex oscillation patterns than observed previously. The actual details of the oscillations depend strongly on the nature of the membrane material, dislosing even the presence of parallel molecular events. It appearsthat sampling topology also has a great influence on the observed oscillato-ry behaviour. Variation of oscillation patterns with...
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Tuning the work function of graphite nanoparticles via edge termination
PublicationGraphite nanoparticles are important in energy materials applications such as lithium-ion batteries (LIBs), supercapacitors and as catalyst supports. Tuning the work function of the nanoparticles allows local control of lithiation behaviour in LIBs, and the potential of zero charge of electrocatalysts and supercapacitors. Using large scale density functional theory (DFT) calculations, we find that the surface termination of multilayer...
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Materials Design for the Titanium Scaffold Based Implant
PublicationThe main objective of here presented research is a design the scaffold/porous titanium(Ti) alloy based composite material demonstrating better biocompatibility, longer lifetime andbioactivity behaviour for load-bearing implants. The development of such material is proposed bymaking a number of consecutive tasks. Modelling the mechanical, biomechanical and biologicalbehavior of porous titanium structure and an elaboration of results...
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Experimental Investigations of Fracture Process Using DIC in Plain and Reinforced Concrete Beams under Bending
PublicationThe fracture behaviour of concrete and reinforced concrete beams under quasi-static three-point bending was comprehensively investigated with experiments at laboratory scale. The eight various concrete mixes were tested. The influence of the shape, volume and size of aggregate particles and reinforcement on concrete fracture under bending was studied. Displacements on the surface of concrete beams were measured by means of the...
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Experimental Study on Effectiveness of a Prototype Seismic Isolation System Made of Polymeric Bearings
PublicationSeismic isolation is identified as one of the most popular and effective methods of protecting structures under strong dynamic excitations. Base isolators, such as Lead Rubber Bearings, High Damping Rubber Bearings, and Friction Pendulum Bearings, are widely used in practice in many earthquake-prone regions of the world to mitigate structural vibrations, and therefore minimize loss of life and property damage during seismic events....
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EXPERIMENTAL ANALYSIS OF RUBBER AND STYROFOAM BUMPERS INFLUENCE ON THE COLLIDING STRUCTURES
PublicationPast and recent investigations of colliding structures under seismic excitation confirmed that pounding may have a significant influence on the structural response. Interactions between adjacent buildings may cause serious damage to the structures, leading even to its total collapse. The main reason of earthquake-induced pounding, besides insufficient distance between structures, are differences in stiffness or mass of colliding structures....
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Badania eksperymentalne modelu zbiornika stalowego na stole sejsmicznym = Experimental study on steel tank model using shaking table
PublicationCylindrical steel tanks are very popular structures used for storage of products of chemical and petroleum industries. Their safety and reliability is really crucial because any failure may have serious consequences. Earthquakes are the most dangerous and also the most unpredictable dynamic loads acting on such structures. On the other hand, rockburst-induced ground motions are usually considered to be less severe due to lower...
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Adhesive Monitoring with Instrumented Wedge Test
PublicationThe wedge test (sometimes called the Boeing wedge test) is amongst the most readily exploitable techniques for assessment of the rate-dependent fracture energy of adhesive materials when used to bond relatively rigid substrates. With its siblings: the double cantilever beam (DCB), and the tapered double cantilever beam (TDCB), a force is applied, essentially in cleavage, to provoke substrate separation perpendicularly to the bondline...
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VALUATION OF EMBEDDED OPTIONS IN NON-MARKETABLE CALLABLE BONDS: A NEW NUMERICAL APPROACH
PublicationThe issue of how to price options embedded in callable bonds has attracted a lot of interest over the years. The usual bond valuation methods rely on yield curves, risk premium, and other parameters to estimate interest rates used in discounted cash flow calculations. The option to retire the bond is, however, neglected in the standard pricing models, causing a systematic overvaluation of callable bonds. In the event of a decline...
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On some problems in determining tensile parameters of concrete model from size effect tests
PublicationThe paper presents results of numerical simulations of size effect phenomenon in concrete specimens. The behaviour of in-plane geometrically similar notched and unnotched beams under three-point bending is investigated. In total 18 beams are analysed. Concrete beams of four different sizes and five different notch to depth ratios are simulated. Two methods are applied to describe cracks. First, an elasto-plastic constitutive law...
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Evaluation of organic coatings condition with AFM-based method
PublicationThe paper presents an atomic force microscopy (AFM)-based approach to evaluation of local protective properties of organic coatings. Apart from topography, it provides local ac and dc characteristics of examined coating. The method consists in application of ac voltage perturbation signal between conductive AFM tip and coated metal substrate. The resulting current is used to determine local impedance characteristics. Both impedance...
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FEM analysis of composite materials failure in nonlinear six field shell theory
PublicationThe monography deals with the problem of failure initiation in thin laminated composites. Known techniques of laminate structures modelling are briefly characterised. Eventually, shell based approach is chosen for the purpose of the description of the composite structures behaviour, as it predicts their deformation and states of stress effectively in a global sense. The nonlinear six parameter shell theory (6p theory) with asymmetric...
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Estimation of Failure Initiation in Laminated Composites by means of Nonlinear Six-Field Shell Theory and FEM
PublicationThe monography deals with the problem of failure initiation in thin laminated composites. Known techniques of laminate structures modelling are briefly characterised. Eventually, shell based approach is chosen for the purpose of the description of the composite structures behaviour, as it predicts their deformation and states of stress effectively in a global sense. The nonlinear six parameter shell theory (6p theory) with asymmetric...
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The effect of macro polymer fibres length and content on the fibre reinforced concrete
PublicationThe paper presents studies of a ready-mix concrete containing polymer fibres of three different lengths: 24, 38 and 54 mm. The performed tests allowed to determine the effect of fibre volume fraction and length on the concrete strength. The basic parameters of concrete mixture (consistency, air content and bulk density) were identified. Fibre reinforced concrete belongs to a group of composite materials. The polymer fibres are...
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Integration of a Multilevel Transport System Model into Sustainable Urban Mobility Planning
PublicationWhen planning their transport policy, cities usually focus on developing sustainable transport systems and reducing the negative consequences of transport. One way to deliver transport policies is to use the Sustainable Urban Mobility Plan (SUMP), a strategic document designed to meet the demand for mobility whilst ensuring adequate quality of life for the residents. The process of Sustainable Urban Mobility Planning (SUMP process)...
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Deep Instance Segmentation of Laboratory Animals in Thermal Images
PublicationIn this paper we focus on the role of deep instance segmentation of laboratory rodents in thermal images. Thermal imaging is very suitable to observe the behaviour of laboratory animals, especially in low light conditions. It is an non-intrusive method allowing to monitor the activity of animals and potentially observe some physiological changes expressed in dynamic thermal patterns. The analysis of the recorded sequence of thermal...
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Earthquake-Induced Pounding Between Asymmetric Steel Buildings
PublicationEarthquake-induced pounding between buildings has been the subject of numerous numerical and experimental studies in the resent years. The phenomenon may cause severe damage to structural elements as well as may also lead to the total collapse of colliding structures. A major reason leading to pounding between adjacent, insufficiently separated buildings results from the differences in their dynamic properties. The aim of this...
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Compliance tests of the polymer layers used as hydrodynamic bearing coatings
PublicationOperational experience and scientific investigations results showed that polymer lined hydrodynamic bearings can withstand more severe operating conditions compared than white metal bearings. PTFE and PEEK-based coatings are the most frequently used as Babbitt alternatives. Both polymers differ significantly from the each other in material properties. According to catalogue data compression modulus of PTFE, it is about an order...
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A biochemical multi-species quality model of a drinking water distribution system for simulation and design
PublicationDrinking Water Distribution Systems (DWDSs) play a key role in sustainable development of modern society. They are classified as critical infrastructure systems. This imposes a large set of highly demanding requirements on the DWDS operation and requires dedicated algorithms for on-line monitoring and control to tackle related problems. Requirements on DWDS availability restrict the usability of the real plant in the design phase....
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Modelling tunnelling-induced deformation in stiff soils with a hyperelastic–plastic anisotropic model
PublicationIn this paper, the tunnelling-induced deformation in anisotropic stiff soils is analysed using FE modelling. The influence of material description is investigated rather than an advanced simulation of the tunnelling method. A new hyperelastic– plastic model is proposed to describe the anisotropic mechanical behaviour of stiff highly overconsolidated soil. This model can reproduce the superposition of variable stress-induced anisotropy...
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Experimental ORC micro-power plant for CHP application Part B: Radial and Multi-stage axial turbines
PublicationThe co-generative micro-power plant with the HFE7100 applied as a working medium was designed and built for experimental investigations. Special attention is paid to a micro-turbine which was built and tested in two variants: a radial turbine and an axial turbine. A concept of a radial turbine with 2 centripetal and 2 centrifugal stages is shown. This prototype was equipped with an aerostatic gas bearing and, alternatively, with...
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Analysis of Historic Brick Walls' Strengthening Methods
PublicationAnalysis of the behavior of historical brick walls is difficult and complicated. However, computer calculations are being increasingly used in the evaluation of cultural heritage buildings and some of their elements. The aim of this paper is to analyze the historic brick walls reinforcement. Different methods of strengthening are compared and discussed. Numerical analysis, based on finite element method, was conducted on the assumption...
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Earthquake-induced pounding between asymmetric steel buildings
PublicationEarthquake-induced pounding between buildings has been the subject of numerous numerical and experimental studies in the resent years. The phe-nomenon may cause severe damage to structural elements as well as may also lead to the total collapse of colliding structures. A major reason leading to pounding between adjacent, insufficiently separated buildings results from the differences in their dynamic properties. The aim of this...
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Analiza pokrycia powierzchni terenu przez działanie robota mobilnego w otoczeniu przeszkód ruchomych
PublicationW artykule została opisana metodyka rozwiązania problemu całkowitego pokrycia nieznanej powierzchni przez autonomicznego robota mobilnego podczas jednoczesnego unikania kolizji z przeszkodami ruchomymi. Przedstawiono sformułowanie oraz dokonano szczegółowej analizy obu problemów, ze zwróceniem szczególnej uwagi na występujące ograniczenia. Zaprezentowano behawioralne podejście do sterowania robotem mobilnym wzorowane na reakcjach...
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Effects of the Covid-19 travel restrictions on metropolises mobility: empirical evidence from the Tricity metropolis (Poland)
PublicationThis paper aims to assess changes in mobility and modal shift caused by COVID-19 travel restrictions among the residents of Gdańsk Bay Metropolis (Poland). Measurement’s moments were assumed in periods differing in the level of restric- tions. The computer-assisted telephone interview (CATI) was carried out in November and December 2020. The results did not confirm the expected modal shift. However, significant changes in the number...
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A novel in vivo approach to assess strains of the human abdominal wall under known intraabdominal pressure
PublicationThe study concerns mechanical behaviour of a living human abdominal wall. A better mechanical understanding of a human abdominal wall and recognition of its material properties is required to find mechanically compatible surgical meshes to significantly improve the treatment of ventral hernias. A non-invasive methodology, based on in vivo optical measurements is proposed to determine strains of abdominal wall corresponding to...
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Influence of addition of carbon nanotubes on rheological properties of selected liquid lubricants - a computer simulation study
PublicationThis work is motivated by the improvement of anti-friction properties of lubricants by addition of CNTs proved experimentally in literature. In particular, a methodology is developed to compute the shear viscosity of liquid lubricants (Propylene Glycol) based on Molecular Dynamics simulation. Non-Equilibrium molecular dynamics (NEMD) approach is used with a reactive force field ReaxFF implemented in LAMMPS. The simulations are...
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Stress–strain model of lower corroded steel plates of normal strength for fitness-for-purpose analyses
PublicationThis study investigates the mechanical properties of specimens made of normal strength steel subjected to lower marine immersed corrosion degradation levels (below 25 %). The specimens were corroded in laboratory conditions, and only natural factors were controlled to raise the corrosion rate (reaching the level of 1 mm/year). Three different thicknesses of plates made of normal strength of shipbuilding steel are investigated (between...
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Porosity and shape of airborne wear microparticles generated by sliding contact between a low-metallic friction material and a cast iron
PublicationThe wear of brakes in transport vehicles is one of the main anthropogenic sources of airborne particulate matter in urban environments. The present study deals with the characterisation of airborne wear microparticles from a low-metallic friction material / cast iron pair used in car brakes. Particles were generated by a pin-on-disc machine in a sealed chamber at sliding velocity of 1.3 m/s and contact pressure of 1.5 MPa. They...
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Structural and physico-mechanical properties of natural rubber/GTR composites devulcanized by microwaves: Influence of GTR source and irradiation time
PublicationGround tire rubber from car and truck was modified using microwave irradiation at variable time. The irradiated ground tire rubber was used as filler in composites based on natural rubber. The composites, with high content of ground tire rubber, were prepared using an internal batch mixer and subsequently cross-linked at 160℃. The influence of the ground tire rubber source (car/truck) and irradiation time on structure, physico-mechanical...
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The Analysis of Overall Ship Fuel Consumption in Acceleration Manoeuvre using Hull-Propeller-Engine Interaction Principles and Governor Features
PublicationThe problem of reduction of greenhouse gas emissions in shipping is currently addressed by many research works and related industries. There are many existing and visionary technologies and ideas, which are conceptually defined or practically realised. This goal can be achieved in different ways, and reducing fuel consumption is one of the major methods. In these circumstances, the aim of this study is to analyse the possibility...
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Numerical Investigation on Dynamic Performance of a Multi-storey Steel Structure Model and Comparison with Experimental Results
PublicationShaking table testing is the most commonly adopted method to simulate earthquake forces. This approach allows us to analyze the dynamic performance and provides a valuable insight into the dynamics of building structures, which helps to improve their future safety and reliability. The present study aims to conduct a numerical evaluation of dynamic response of a multi-storey steel structure model, which was previously examined during...
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Experiences and Challenges in Fatality Reduction on Polish Roads
PublicationAccording to the UN, road safety is the key to achieving sustainable development goals, yet the complexity of how road accidents happen makes this a difficult challenge leaving many countries struggling with the problem. For years, Poland has infamously been one of the EU’s top countries for road-accident fatality rates. Despite that, it has made significant progress in the last thirty years with a fatality reduction of more than...
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Numerical investigation on dynamic performance of a multi-storey steel structure model and comparison with experimental results
PublicationShaking table testing is the most commonly adopted method to simulate earthquake forces. This approach allows us to analyze the dynamic performance and provides a valuable insight into the dynamics of building structures, which helps to improve their future safety and reliability. The present study aims to conduct a numerical evaluation of dynamic response of a multi-storey steel structure model, which was previously examined during...