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Evaluation of organic coatings condition with AFM-based method
PublikacjaThe 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
PublikacjaThe 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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Integration of a Multilevel Transport System Model into Sustainable Urban Mobility Planning
PublikacjaWhen 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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Estimation of Failure Initiation in Laminated Composites by means of Nonlinear Six-Field Shell Theory and FEM
PublikacjaThe 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
PublikacjaThe 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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Experimental Study on Effectiveness of a Prototype Seismic Isolation System Made of Polymeric Bearings
PublikacjaSeismic 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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Modelling tunnelling-induced deformation in stiff soils with a hyperelastic–plastic anisotropic model
PublikacjaIn 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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Analiza pokrycia powierzchni terenu przez działanie robota mobilnego w otoczeniu przeszkód ruchomych
PublikacjaW 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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Colloidal transport of lipid digesta in human and porcine small intestinal mucus
PublikacjaSmall intestinal mucus transport of food-derived particulates has not been extensively studied, despite mucus being a barrier nutrients need to cross before absorption. We used complex dispersions of digesta obtained from simulated, dynamic gastrointestinal digestion of yogurt to examine the penetrability of human and porcine mucus to the particles formed of lipolysis products. Quantitative, time-lapse confocal microscopy revealed...
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Influence of addition of carbon nanotubes on rheological properties of selected liquid lubricants - a computer simulation study
PublikacjaThis 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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A novel in vivo approach to assess strains of the human abdominal wall under known intraabdominal pressure
PublikacjaThe 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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Stress–strain model of lower corroded steel plates of normal strength for fitness-for-purpose analyses
PublikacjaThis 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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The Analysis of Overall Ship Fuel Consumption in Acceleration Manoeuvre using Hull-Propeller-Engine Interaction Principles and Governor Features
PublikacjaThe 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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Porosity and shape of airborne wear microparticles generated by sliding contact between a low-metallic friction material and a cast iron
PublikacjaThe 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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Earthquake-induced pounding between asymmetric steel buildings
PublikacjaEarthquake-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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Experimental ORC micro-power plant for CHP application Part B: Radial and Multi-stage axial turbines
PublikacjaThe 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
PublikacjaAnalysis 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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Numerical Investigation on Dynamic Performance of a Multi-storey Steel Structure Model and Comparison with Experimental Results
PublikacjaShaking 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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Numerical investigation on dynamic performance of a multi-storey steel structure model and comparison with experimental results
PublikacjaShaking 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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Structural and physico-mechanical properties of natural rubber/GTR composites devulcanized by microwaves: Influence of GTR source and irradiation time
PublikacjaGround 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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Experiences and Challenges in Fatality Reduction on Polish Roads
PublikacjaAccording 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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Effects of the Covid-19 travel restrictions on metropolises mobility: empirical evidence from the Tricity metropolis (Poland)
PublikacjaThis 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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Influence of soil anisotropic stiffness on the deformation induced by an open pit excavation.
PublikacjaIn this paper, the problem of deformation induced by an open pit excavation in anisotropic stiff soils is analysed by FE modelling. The presented research is focused on the influence of material model with anisotropic stiffness on the accuracy of deformation predictions as compared with the field measurements. A new hyperelastic-plastic model is applied to simulate anisotropic mechanical behaviour of stiff soils. It is capable...
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Biowaste chicken eggshell powder as a potential cure modifier for epoxy/anhydride systems: competitiveness with terpolymer-modified calcium carbonate at low loading levels
PublikacjaBiowaste chicken eggshell (ES) powder was applied as a potential cure modifier in epoxy/anhydride systems. Cure behaviour and kinetics of composites filled with very low content (0.1 wt% based on epoxy resin) of ES, calcium carbonate (CaCO3), and terpolymer-modified fillers, mES and mCaCO3, were discussed comparatively. Surface analysis was performed by X-ray photoelectron spectroscopy. Cure kinetics was investigated by differential...
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Indoor accelerated controlled corrosion degradation test of small- and large-scale specimens
PublikacjaThe work presented here is a part of a long-term project analysing the structural behaviour of ageing marine structures. An accelerated corrosion degradation set-up was developed to reproduce corroded marine structural specimens of different degrees of degradation, controlling various natural factors, i.e., temperature, oxygen content, salinity, and flow velocity. The nine stiffened plates of 1.2 m length and 30 small scale specimens...
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Power Hardware-In-the-Loop Approach for Autonomous Power Generation System Analysis
PublikacjaThe article presents the Power Hardware-In-the-Loop (PHIL) dynamic model of a synchronous generator of 125 kVA for autonomous power generation system analysis. This type of system is typically composed of electrical energy sources in the form of several diesel generator units with synchronous machines, the main distribution switchboard and different loads. In modern power distribution systems, the proposed power management strategies...
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Lighting conditions in Home Office and occupant’s perception: an international study
PublikacjaThe global pandemic and physical distancing restrictions are forcing us to rethink how residential buildings are used regarding the visual environment. This paper describes home office lighting conditions within different countries and continents. The aim is to define the current limitations of home offices in providing a resilient visual environment. The work was developed by a team of international experts working together on...
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Polynomial Chaos Expansion in Bio-and Structural Mechanics
PublikacjaThis monograph presents a probabilistic approach to modelling the mechanics of materials and structures where the modelled performance is influenced by uncertainty in the input parameters. The work is interdisciplinary and the methods described are applied to medical and civil engineering problems. The motivation for this work was the necessity of mechanics-based approaches in the modelling and simulation of implants used in the...
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The Role of Greenery and Traffic Calming Measures in Planning of Road Infrastracture
PublikacjaThe role of greenery and traffi c calming measures in road infrastructure planning. The “life” of a town is connected with its infrastructure. So it is that, apart from serving their principal function, motorways, roads, airports and other facilities which make transport possible largely determine contemporary urban design. To achieve balanced forms of urban infrastructure that ensure comfort, safety and spatial order, it is necessary when...
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Tuning of photocatalytic activity by creating a tridentate coordination sphere for palladium
PublikacjaThe synthesis and characterisation of an asymmetric potential bridging ligand bmptpphz (bmptpphz = 2,17-bis(4-methoxyphenyl)tetrapyrido[3,2-a:2’,3’-c:3’’,2’’-h:2’’’,3’’’-j] phenazine) is presented. This ligand contains a 1,10-phenanthroline (phen) and a 2,9-disubstituted phen sphere and possesses a strong absorbance in the visible. Facile coordination of the phen sphere to a Ru(tbbpy)2 core leads to Ru(bmptpphz) ([(tbbpy)2Ru(bmptpphz)](PF6)2;...
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Viscous versus electromagnetic damping – amplification in a neighbourhood of a mechanism singular position
PublikacjaIn the paper, damping of vibrations are considered and compared in a mechanical and in a electromechanical system. In the system, a continuous beam is considered as the main vibrating element. The compared dissipations methods are based on: viscous dampers and DC generators. To increase the possible damping effectiveness, velocity amplification is proposed, i.e., a mechanism is introduced between the beam and the damping element....
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Design and investigations of a micro-turbine flow part
Publikacja-generative micro-power plant with the HFE7100 as a working medium was designed and built for experimental investigations. The heat output of the plant was assumed equal to 20 kW, while the electric output amounted to about 3kW.In the paper a multi-stage micro-turbine with partial admission of all the stages is described in detail and the results of the particular experimental investigations and numerical calculations are shown,...
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Distillery Fusel Oil as an Alternative Carbon Source for Denitrification – from Laboratory Experiments to Full-Scale Applications
PublikacjaIndustrial waste products may be a viable alternative to commercial external carbon sources. In this study, the properties of fusel oil (distillery waste product) were investigated in terms of temperature dependency of denitrification and acclimation period. Furthermore, results obtained during three different full-scale trials were used to verify similarities and differences with the results obtained under laboratory-scale conditions....
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Biomarkers of alcohol consumption in body fluids - possibilities and limitations of application in toxicological analysis
PublikacjaEthyl alcohol is the most popular legal drug, but its excessive consumption causes social problems. Despite many public campaigns against alcohol use, car accidents, instances of aggressive behaviour, sexual assaults and deterioration in labor productivity caused by inebriated people is still commonplace. Fast and easy diagnosis of alcohol consumption is required in order to introduce proper and effective therapy, and is crucial...
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Polynomial Chaos Expansion in Bio- and Structural Mechanics
PublikacjaThis thesis presents a probabilistic approach to modelling the mechanics of materials and structures where the modelled performance is influenced by uncertainty in the input parameters. The work is interdisciplinary and the methods described are applied to medical and civil engineering problems. The motivation for this work was the necessity of mechanics-based approaches in the modelling and simulation of implants used in the repair...
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TB11 test for short w-beam road barrier
PublikacjaFEM (Finite Element Method) is well-suited and widely used tool for simulating a range of phenomena: from these with simple and static behaviour, up to those complicated, highly nonlinear and involving many contacts. In present paper we use one of the advantages of FEM: parametric study could be easily performed and is more economical than series of in-situ tests. If recommended practices is carefully followed, results obtained...
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Antibiotic-sterol interactions provide insight into the selectivity of natural aromatic analogues of amphotericin B and their photoisomers
PublikacjaAromatic heptaene macrolides (AHMs) belong to the group of polyene macrolide antifungal antibiotics. Members of this group were the first to be used in the treatment of systemic fungal infections. Amphotericin B (AmB), a non-aromatic representative of heptaene macrolides, is of significant clinical importance in the treatment of internal mycoses. It includes the all-trans heptaene chromophore, whereas the native AHMs contain two...
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Fe-modified Mn2CuO4 spinel oxides: coatings based on abundant elements for solid oxide cell interconnects
PublikacjaThe current state of the art steel interconnect coating materials are based on critical raw material - Co-oxide spinels. Replacing Co-oxide spinels with alternative, abundant materials can reduce the dependence on the critical raw materials. Cobalt-free coatings with the general formula Mn2-xCuFexO4, where x = 0, 0.1, 0.3, were electrophoretically deposited on a ferritic stainless-steel support and evaluated. Prior to deposition,...
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Multilayer coatings based on cerium oxide and manganese cobaltite spinel for Crofer22APU SOC interconnects
PublikacjaThe current state of the art steel interconnect coating materials are based on critical raw material - Co-oxide spinels. Replacing Co-oxide spinels with alternative, abundant materials can reduce the dependence on the critical raw materials. Cobalt-free coatings with the general formula Mn2-xCuFexO4, where x = 0, 0.1, 0.3, were electrophoretically deposited on a ferritic stainless-steel support and evaluated. Prior to deposition,...
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MICROPROPAGATION, ANTIOXIDANT ACTIVITY, TOTAL PHENOLICS AND FLAVONOIDS CONTENT OF GARDENIA JASMINOIDES ELLIS AS AFFECTED BY GROWTH REGULATORS
PublikacjaThis investigation has been carried out to study Micropropagation of Gardenia jasminoides Ellis shootlet,induction and growth of callus and enhancement of antioxidant, total phenolics and flavonoids content in shootlet andcalli. The results revealed that for shooting stage adding 2 or 3 mg/l BAP gave the highest shootlet number/explant. Butadding 3 mg/l 2iP produced the longest shootlet and leaves number. The...
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Evaluating the convenience and safety effects of bicycle lanes in Gdańsk
PublikacjaBicycle lanes are lanes marked on a road and dedicated for exclusive use for cyclists.. Because they combine bike and motor traffic they provide directness and flow. However, a shared use of streets could result in bicycle-car accidents. Following up on the good practice Western countries have in planning cycle infrastructure, Gdańsk has recently introduced bike lanes on a few streets. The aim of the research was to assess the...
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Integrating Digital Twin Technology Into Large Panel System Estates Retrofit Projects
PublikacjaAs sustainability is now a standard for the proposed developments, the focus ought to be shifted towards the existing buildings and, among them, the worldwide stock of large panel system (LPS) buildings. Major upgrades and retrofits were done to some of the LPS estates in Germany and France, but a leading sustainable way must still be developed for LPS buildings in Eastern European countries, where apartments in those half‐a‐century‐old...
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Application of the ISE Optimized Proportional Control of the Wave Maker in a Towing Tank
PublikacjaThis paper presents the improvement of the wave maker control system. The wave maker is a facility widely used in hydromechanics laboratories to generate waves in towing tanks. It is equipped with an electrohydraulic drive and an actuator submerged into water. The waves are generated to model the environmental conditions for physical experiments, performed on reduced-scale models of maritime objects. The physical experiments allow...
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Amperometric sensing of chemical oxygen demand at glassy carbon and silicon electrodes modified with boron-doped diamond
Publikacja.A boron-doped diamond (BDD) sensor is proposed for effective detection of chemical oxygen demand (COD) by means of amperometric technique. Boron-doped diamond thin films, acting as active sensors, were deposited on both silicon wafer and glassy carbon (GC) substrates by microwave plasma assisted chemical vapour deposition. SEM micrographs showed that BDD–Si displays triangle-faceted crystallites ca. 0.5–3 μm in size, while BDD–GC...
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Preparation and structure of nanocrystalline sol-gel derived Cu doped LiTi2O4 powders
PublikacjaAmong the spinel oxides materials, lithium titanate (Li1+xTi2-xO4 where 0 ≤ x ≤ 0.33) could be very interested from pratical applications point of view. Lithium titanate is a II type spinel oxide superconductor with relatively high (~13 K for x = 0) superconducting transition temperature Tc. Above Tc lithium titanate shows metallic behaviour and can be used e.g. as electrodes for rechargeable lithium-ion batteries. Since the discovery...
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Electrical properties and structure of lead-borate glass containing iron ions.
PublikacjaThe ac and dc conductivity in iron–lead-borate glass samples was investigated in the frequency range from 1 mHz to 1 MHz and in the temperature range from 153 K to 423 K. The structure was investigated by the means of atomic force microscopy (AFM) and the crystalline phases (if present) were identified by the means of X-ray diffractometry. Two types of ac electrical behaviour were observed. The first group of glass samples which...
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Preparation, morphology and properties of natural rubber composites filled with untreated short jute fibres
PublikacjaGreen composites were obtained by incorporation of short jute fibres in natural rubber matrix using a laboratory two-roll mill. The influence of untreated fibre content (1, 2.5, 5, 7.5 and 10 phr) on the mechanical properties, dynamic mechanical properties, swelling properties was examined. The behaviour of prepared green composites under cyclic compression was also investigated. Fibre dispersion in rubber matrix was studied by...
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Pedestrian protection, speed enforcement and road network structure the key action for implementing Poland's Vision Zero
PublikacjaSince 1991 Poland's road safety has been systematically improving with a 60% reduction in road deaths. Despite the progress Poland continues to be one of the European Union' worst performing countries. The country's main road safety problems remain unchanged: dangerous behaviour of road users, underdeveloped system of road safety management and low quality of road infrastructure. This is why subsequent road safety programmes (implemented...
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Strategies for mitigating nitrous oxide production and decreasing the carbon footprint of a full-scale combined nitrogen and phosphorus removal activated sludge system
PublikacjaNitrous oxide (N2O) emitted from biological nutrient removal activated sludge systems contributes significantly to the total carbon footprint of modern wastewater treatment plants. In the present study, N2O production and emissions were experimentally determined in a large-scale plant (220,000 PE) employing combined nitrogen (N) and phosphorus (P) removal. As a modelling tool, the Activated Sludge Model 2d (ASM2d) was extended...
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Analysis of temporary steel grandstand with different bracing systems exposed to crowd load
PublikacjaGrandstands are structures which are regularly subjected to dynamic loads generated by crowd motions. It is a dangerous situation when spectators induce rhythmic jumping, dancing, stamping, etc. If the synchronized movement of spectators excites a natural frequency of the structure, resonant response might occur. To avoid such situations, temporary steel grandstands are commonly strengthened using additional elements that create...