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Correlations of structural, thermal and electrical properties of sodium doped complex borophosphosilicate glass
PublicationBorophosphosilicate glasses with varying sodium ion concentrations were investigated for their, structural, thermal, and electrical properties. All the obtained glasses were transparent except the glass with the highest sodium content, which exhibited translucency due to inhomogeneities. Increasing sodium content led to reduced boron and silicon content while maintaining a constant B/Si ratio, indicating progressive depolymerization...
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Shape memory thin films of Polyurethane: Does graphene content affect the recovery behavior of Polyurethane nanocomposites?
PublicationThin nanocomposite films of polyurethane have received remarkable attention due to their shape memory properties. As most of the reports focus on the beneficial aspects of the presence of nanofillers such as graphene nanoplatelets (GNPs) introduced into shape memory polymers, some research results reveal the opposite trend. The polyether/polyester-based polyurethane was synthesized through a condensation polymerization and the...
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Comparison of Properties of the Hybrid and Bilayer MWCNTs—Hydroxyapatite Coatings on Ti Alloy
PublicationCarbon nanotubes are proposed for reinforcement of the hydroxyapatite coatings to improve their adhesion, resistance to mechanical loads, biocompatibility, bioactivity, corrosion resistance, and antibacterial protection. So far, research has shown that all these properties are highly susceptible to the composition and microstructure of coatings. The present research is aimed at studies of multi-wall carbon nanotubes in three different...
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Morphology, Thermo-Mechanical Properties and Biodegradibility of PCL/PLA Blends Reactively Compatibilized by Different Organic Peroxides
PublicationReactive blending is a promising approach for the sustainable development of bio-based polymer blends and composites, which currently is gaining more and more attention. In this paper, biodegradable blends based on poly(ε-caprolactone) (PCL) and poly(lactic acid) (PLA) were prepared via reactive blending performed in an internal mixer. The PCL and PLA content varied in a ratio of 70/30 and 55/45. Reactive modification of PCL/PLA...
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Mechanical exfoliation and layer number identification of single crystal monoclinic CrCl3
PublicationAfter the recent finding that CrI3, displays ferromagnetic order down to its monolayer, extensive studies have followed to pursue new two-dimensional (2D) magnetic materials. In this article, we report on the growth of single crystal CrCl3 in the layered monoclinic phase. The system after mechanical exfoliation exhibits stability in ambient air (the degradation occurs on a time scale at least four orders of magnitude longer than...
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Thermal Transitions and Structural Characteristics of Poly(3,4-ethylenedioxythiophene/cucurbit[7]uril) Polypseudorotaxane and Polyrotaxane Thin Films
PublicationHerein, we report the thermal transitions and structural properties of poly(3,4-ethylenedioxythiophene/cucurbit[7]uril) pseudopolyrotaxane (PEDOT∙CB7-PS) and polyrotaxane (PEDOT∙CB7-PR) thin films compared with those of pristine PEDOT. The structural characteristics were investigated by using variable-temperature spectroscopic ellipsometry (VTSE), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and atomic force...
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UWARUNKOWANIA I SKUTKI ŻYWIOŁOWEJ SUBURBANIZACJI W POLSCE. CZY OPANOWANIE JEJ JEST MOŻLIWE?
PublicationArtykuł dotyczy procesu żywiołowej suburbanizcji (urban sprawl) w Polsce. Jego celami są: (1) analiza powiązań między negatywnymi skutkami tego procesu, (2) prezentacja negatywnych skutków dla transportu i zużycia energii oraz ładu przestrzennego, (3) analiza sposobów przeciwdziałania negatywnym procesom, w tym uwarunkowań (w szczególności ograniczeń) stosowania tych sposobów i ich skuteczności. Jako metody zastosowano: obserwację,...
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Rozumieć Kanta całościowo czyli o Opus postumum Immanuela Kanta
PublicationTekst pokazuje fundamentalne znaczenie Opus postumum Kanta dla zrozumienia całości jego filozofii, dynamiki jej rozwoju, jej trudności i niekonsekwencji. Podstawowym problemem jest tu problem przejścia od metafizyki przyrody do fizyki. Omawiając pracę Tomasza Kupścia tekst pokazuje jak ważne w rozumieniu Kanta jest wyjście poza problematykę filozofii przyrody w stronę filozofii Boga, bo zwieńczenie filozofii transcendentalnej...
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Zmiany udziału pracy w dochodzie narodowym a nierówności społeczne na przykładzie państw Grupy Wyszehradzkiej
PublicationDokonująca się liberalizacja handlu, rynków pieniężnych i kapitałowych, umiędzynaro-dowienie produkcji oraz szybkie i szerokie wykorzystanie technologii stanowiące siłę napędową globalizacji włączyły, transformującą się gospodarkę polską w ten proces. Globalizacja określa rozprzestrzenianie się charakterystycznych trendów światowej ekonomii, polityki, życia społecznego i kultury na całym świecie, niezależnie od stopnia zaawansowania...
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Education of Logisticians in Poland: Problems and Prospects in Students’ Opinion
PublicationLogistics is one of the key sectors of the Polish economy. Its value reflects not only its own capacity, but also the role it plays in ensuring the proper functioning of the entire economy. The rapid development of the industry and the highest demands on logistics solutions bring to the fore the problem of preparing a new generation of specialists in logistics. That is why the question of compliance to learning expectations of...
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Challenges of branding and marketing of clusters
PublicationClusters have proved to be powerful engine s of economic development in the European Union. Clusters and their stakehol ders can derive many benefits fr om a strong cluster brand. However, they face numerous branding and marketing challenges. Specifics of clusters, such as multiple stakeholders, make it difficult to forge a strong brand identity. This paper addresses the need to develop a cluster specific approach to branding and...
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Can Communication Power of Separable Correlations Exceed That of Entanglement Resource?
PublicationThe scenario of remote state preparation with a shared correlated quantum state and one bit of forward communication [B. Dakić et al., Nat. Phys. 8, 666 (2012)] is considered. Optimization of the transmission efficiency is extended to include general encoding and decoding strategies. The importance of the use of linear fidelity is recognized. It is shown that separable states cannot exceed the efficiency of entangled states by...
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Environmental Fate of Two Psychiatric Drugs, Diazepam and Sertraline: Phototransformation and Investigation of their Photoproducts in Natural Waters
PublicationExperimental studies were conducted to investigate the photodegradation of diazepam and sertraline, two of the most frequently used psychiatric drugs, induced by xenon lamp irradiation, which overlap the sunlight spectra, and natural sunlight. Degradation kinetics was established indicating the occurrence of autocatalytic reactions. The application of liquid chromatography coupled to quadrupole time-of-flight mass spectrometry...
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Effect of Compounding Conditions on Static and Dynamic Mechanical Properties of High Density Polyethylene/Ground Tire Rubber Blends
PublicationSearching for new and cost-effective methods of waste rubber recycling is a subject of research in many scientific centers in the world. In this paper there are presented results of the research of the extrusion process of cheap and environmentally friendly thermoplastic compositions containing 50 % wt. of masses of ground tire rubber (GTR). The aim of this study was to determine the relationship between the mixing conditions and...
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Changing by light - how the lighting of intelligent spaces can influence the urban image
PublicationIn the article light will be presented as a tool in the process of transforming the urban space. The reason for this use of light is the commercial aspect of space that forces it to be still competitive and profitable. Such a need gives rise to many innovative solutions in the city space, which allow transmitting information in order to attract human attention, and sometimes make it even possible to involve the user in the interaction...
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CSR and small business from the international and national perspective
PublicationCorporate and social responsibility is nowadays quite a popular topic among large companies but thanks to numerous popularization activities undertaken by national and international institutions, also small entrepreneurs become more and more interested in exploring this fairly new approach. This paper outlines the main differences between the implementation of the CSR approach in large companies and in SMEs, which are not able...
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Thermo-resonance analysis of an excited graphene sheet using a new approach
PublicationForced vibration of graphene nanoplate based on a refined plate theory in conjunction with higher-order nonlocal strain gradient theory in the thermal environment has been investigated. Regarding the higher-order nonlocal strain gradient theory, both stress nonlocality and size-dependent effects are taken into account, so the equilibrium equations which are governing on the graphene sheet have been formulated by the theory....
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Experimental study on steel columns subjected to impact load under earthquake conditions
PublicationEarthquakes affecting urbanized regions cause exceptional loads to load bearing structural elements such as columns. Such a boost in the load conditions can lead to severe damages which, in a worst case scenario, can lead to a total collapse of a building. This boost is caused by the horizontal ground movement generating a rise in the internal forces due to considerable large displacement between the top and bottom support of columns....
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Compensation of pressure peaks in pwk-type hydraulic pumps
Publicationhydraulic axial pumps equipped with cam-driven commutation unit (pwk pumps) proved their high efficiency up to 55 mpa and ability to work self-sucking, even at high speed. displacement of pwk pump may easily be changed by moving its control cam. full discharge from hydrostatic forces makes such control possible by direct action of a low-energy actuator like proportional electromagnet or stepping motor. that eliminates heavy and...
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Skilled-Unskilled Wage Gap Versus Evolving Trade And Labour Market Structures in the EU
PublicationThis paper proposes an alternative approach to the empirical study of wage gap between workers with different educational levels in the enlarged EU. The analysis is based on sectoral database, linking labor market statistics and trade data at the level of 12 manufacturing sectors in a group of 20 European countries: selected New Member States (NMS-5) and former EU-15 economies, in the period 1995-2005. The results of the empirical...
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Correlation between natural frequencies and buckling load in a stiffened shell
PublicationThe paper deals with correlation between natural frequencies and buckling load of a stiffened shell composed of corrugated sheets and vertical stiffeners (columns). The simplified shell segment represents the buckling behaviour of a whole silo with sparsely distributed columns. The paper covers variants of linear buckling anal-yses, dynamic eigenvalue analyses and geometrically non-linear analyses of a segment modelled with shell...
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Seismic pounding between adjacent buildings: Identification of parameters, soil interaction issues and mitigation measures
PublicationStructural pounding has been observed in many previous earthquakes due to insufficient gap commonly provided between adjacent structures. The collisions usually generate large impact forces and short duration acceleration pulses which may result in significant damage to the colliding buildings. Because of that, earthquake induced structural pounding has been intensively studied and investigated for the last three decades. Results...
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SPECTRAL DYNAMIC ANALYSIS OF A STATIONARY JACK-UP PLATFORM
PublicationThe paper refers to the dynamic short-term response analysis of the Baltic steel drilling platform (see Fig.2) in a random sea-state represented by one-dimensional wave spectrum proposed by Striekalov and Massel and it is recommended for the Baltic Sea area. The Baltic drilling platform is a jack-up type platform for the exploration and exploitation of oil under the Baltic Sea. The analysis presented deals with the stationary...
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A Preliminary Study and Analysis of Tidal Stream Generators
PublicationFor a sustainable future, tidal energy can play a vital role. Tidal energy relies on the gravitational pull of the Moon and the Sun along with the centrifugal forces created by the Earth. Tidal barrage uses the potential energy from the tide and has been very successful in electricity production. With the help of a turbine, kinetic energy can also be harnessed from tidal currents to generate electricity. However, it is not economically...
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Improvement of Performance Level of Steel Moment-Resisting Frames Using Tuned Mass Damper System
PublicationIn this paper, parameters of the tuned mass dampers are optimized to improve the performance level of steel structures during earthquakes. In this regard, a six-story steel frame is modeled using a concentrated plasticity method. Then, the optimum parameters of the Tuned Mass Damper (TMD) are determined by minimizing the maximum drift ratio of the stories. The performance level of the structure is also forced to be located in a...
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Do morphometric parameters and geological conditions determine chemistry of glacier surface ice? Spatial distribution of contaminants present in the surface ice of Spitsbergen glaciers (European Arctic)
PublicationAbstract The chemism of the glaciers is strongly determined by long-distance transport of chemical substances, and their wet and dry deposition on the glacier surface. This paper concerns spatial distribution of metals, ions, and dissolved organic carbon, as well as the differentiation of physicochemical parameters (pH, electrical conductivity) determined in ice surface samples collected from four Arctic glaciers during the summer...
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Electromodulation of photoluminescence in vacuum-evaporated films of bathocuproine
PublicationElectric field-modulated photoluminescence (EML) was measured in vacuum-evaporated films of bathocuproine (BCP), electron-transporting material commonly used in organic light-emitting diodes (OLEDs). The external electric field of 106 V/cm strength decreases long-wavelength photoluminescence (PL) up to 10% but the same effect on short-wavelength PL is above one order of magnitude smaller. The distinctive difference between the...
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Professional activity and women entrepreneurship in Poland – Europe 2020 Strategy perspective
PublicationThe level of economic activity of women in Poland is the lowest among Baltic Sea Region countries. The analysis of Europe 2020 targets, shows that at least 3 of the 5 main objectives relate, more or less, to women (e.g. participation in labor market). The objective concerning social inclusion assumes the increase in the employment rate of men and women (aged 20-64) in Poland up to 71%. To achieve this goal, support programs to...
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Alternative convolution approach to friction in unsteady pipe flow
PublicationIn the paper some aspects of the unsteady friction in pipe flow expressed by the convolution are analyzed. This additional term introduced into the motion equation involves the accelerations of fluid occurring in the past and a weighting function. The essence of such approach is to assume the appropriate form of weighting function. However, until now no fully reliable formula for this function has been found. To avoid some inconveniences...
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Electrical properties and structure of lead-borate glass containing iron ions.
PublicationThe 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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Wykorzystanie kamery termowizyjnej nowej generacji do oceny wpływu sił ortodontycznych na dziąsło = The application of a new-generation thermal imaging camera for the assessment of hemodynamic changes in gingiva during orthodontic treatment
PublicationIntroduction. One ot the most interesting modern methods of assessing microcirculation is thermovisiual examination. Thermovision cameras are commonly used in general medicine. As the periodontium is one of the most vascularized tissues in the human body, the application of high-sensitivity thermovision cameras may allow tor noninvasive asses- sment and early detection ot pathological changes in the gingiva by giving a complete...
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Intercalation complex of imidazoacridinone C-1311, a potential anticancer drug, with DNA helix d(CGATCG)2: stereostructural studies by 2D NMR spectroscopy.
PublicationImidazoacridinone C-1311 (Symadex®) is a powerful antitumor agent, which successfully made its way through the Phase I clinical trials and has been recommended for Phase II few a years ago. It has been shown experimentally that during the initial stage of its action C-1311 forms a relatively stable intercalation complex with DNA, yet it has shown no base-sequence specificity while binding to DNA. In this paper, the d(CGATCG)2:C-1311...
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Chemical-Assisted Mechanical Lapping of Thin Boron-Doped Diamond Films: A Fast Route Toward High Electrochemical Performance for Sensing Devices
PublicationThere is an urgent need for an effective and economically viable increase in electrochemical performance of boron-doped diamond (BDD) electrodes that are used in sensing and electrocatalytic applications. Specifically, one must take into consideration the electrode heterogeneity due to nonhomogenous boron-dopant distribution and the removal of sp2 carbon impurities saturating the electrode, without interference in material integrity....
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Preparation and properties of composite coatings, based on carbon nanotubes, for medical applications
PublicationThe coatings based on carbon nanotubes (CNTs) are increasingly developed for their applications, among others, in medicine, in particular for implants in implantology, cardiology, and neurology. The present review paper aims at a detailed demonstration of diferent preparation methods for such coatings, their performance, and relationships between deposition parameters and microstructure and material, mechanical, physical, chemical,...
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Sustainable Chemically Modified Mater-Bi/Poly(ε-caprolactone)/Cellulose Biocomposites: Looking at the Bulk through the Surface
PublicationSustainable polymer composites are progressively under development in a technological paradigm shift from "just use more and more" to "convert into value-added products". The bio-based blends based on Mater-Bi bio-plastic (A) and poly(ε-caprolactone) (B), at a weight ratio of 70:30 (A:B) were developed, followed by the addition of UFC100 cellulose (C) filler to yield 70/30 (w/w) (A:B)/C sustainable biocomposites. The effects of...
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Controlling nodal displacement of pantographic structures using matrix condensation and interior-point optimization: A numerical and experimental study
PublicationThis study presents an innovative approach for the precise control of nodal displacements in pantographic structures. The method is founded on the Matrix Condensation of Force Method, seamlessly integrated with an Interior Point Optimization algorithm. This combination offers a unique advantage by allowing users to manipulate displaced nodes within a defined coordination domain. Furthermore, this approach introduces the Interior...
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Experimental study on the feasibility of alternative materials for tilting pad thrust bearings operating in transition to mixed friction
PublicationIn hydrodynamic bearings traditional bearing alloys: Babbitts and bronzes are most frequently utilized. Polymer sliding layers are sometimes applied as a valuable alternative. Hard diamond-like carbon (DLC) coatings, which are also considered for certain applications may show some advantages, as well. Although material selection is of secondary importance in a full film lubrication regime it becomes important in mixed friction...
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Seismic performance evaluation of steel buckling-restrained braced frames including SMA materials
PublicationThe permanent deformation of the building after seismic excitations can be determined by the Maximum Residual Interstory Drift Ratio (MR-IDR), which may be used for measuring the damage states. Low-post yield stiffness of the steel buckling-restrained braced frame (BRBF) makes this system vulnerable to large MR-IDR after a severe earthquake event. To overcome this issue, this paper investigates the seismic limit state performances...
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Selected Aspects of 3D Printing for Emergency Replacement of Structural Elements
PublicationThe paper presents a synthetic characterization of modern methods of manufacturing or regenerating machine elements. Considered methods are machining and additive methods, in particular 3D printing in the FDM/FFF technique. For the study, the authors made samples of the holder bracket using selected methods. Samples made by machining operations, 3D printing with various filling were tested. The paper contains a technical and economic...
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Dependent self-employed individuals: are they different from paid employees?
PublicationThis study focuses on dependent self-employment, which covers a situation where a person works for the same employer as a typical worker while on a self-employment contractual basis, i.e., without a traditional employment contract and without certain rights granted to "regular" employees. The research exploits the individual-level dataset of 35 European countries extracted from the 2017 edition of the European Labour Force Survey...
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GTR/Thermoplastics Blends: How Do Interfacial Interactions Govern Processing and Physico-Mechanical Properties?
PublicationIn this work, GTR/thermoplastics blends (in ratio 50/50 and 75/25 wt.%) were prepared by melt-compounding in an internal mixer. During research, trans-polyoctenamer rubber (TOR), ethylene-vinyl acetate copolymer (EVA), ethylene-octene copolymer (EOC), and linear low-density polyethylene (LLDPE), were used in their thermoplastic phase. Microstructure and processing-performance property interrelationships of the studied materials...
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Marine traffic risk modelling – an innovative approach and a case study
PublicationThis paper presents a model to analyse the risk of two common marine accidents: collision and grounding. Attention is focused on oil tankers since they pose the highest environmental risks. A case study in selected areas of the Gulf of Finland in ice-free conditions is presented. The model utilizes a formula for risk calculation that considers both the probability of an unwanted event and its consequences. The model can be decomposed...
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Electrochemical cobalt oxidation in chloride media
PublicationThe green transition, despite recent advances in cobalt-free battery technologies, is still highly dependent on the availability of critical cobalt-based materials. Consequently, there has been increasing interest towards the development of new methods that maximize critical metals recovery from industrial hydrometallurgical solutions. In the current study, direct anodic oxidation of cobalt species from cobalt chloride solutions...
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Remote measurement of building usable floor area - Algorithms fusion
PublicationRapid changes that are taking place in the urban environment have significant impact on urban growth. Most cities and urban regions all over the world compete to increase resident and visitor satisfaction. The growing requirements and rapidity of introducing new technologies to all aspects of residents' lives force cities and urban regions to implement "smart cities" concepts in their activities. Real estate is one of the principal...
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The fracture behaviour of notched PMMA specimens under simple loading conditions – Tension and torsion experimental tests
PublicationThis paper presents the results of experimental testing of flat PMMA specimens during uniaxial loading conditions. Two separate tests were conducted: tensile and torsion. The specimens were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. The specimens were made in two thickness variants: 5 and 15 mm. Monotonic tensile and torsion tests were carried out while keeping the averaged strain rate constant,...
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Study of the formation of calcareous deposits on cathodically protected steel in Baltic sea water
PublicationPurpose – The purpose of this paper is to investigate whether the sedimentation of calcareous deposits occurs on cathodically protected steel in Baltic sea water. Design/methodology/approach – Steel electrodes were cathodically polarized in natural Baltic sea water at potential þ0.150 V vs Zn electrode in potentiostatic mode. During exposure chronoamperometric measurements were carried out. After the exposure, the electrode’s surface...
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Advanced Hysteretic Model of a Prototype Seismic Isolation System Made of Polymeric Bearings
PublicationThe present paper reports the results of acomprehensive study designed to verify the effectiveness of an advanced mathematical model in simulating the complex mechanical behaviour of a prototype seismic isolation system made of polymeric bearings (PBs). Firstly, in order to construct the seismic bearings considered in this research, a specially prepared flexible polymeric material with increased damping properties was employed....
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The changes of crosslink density of polyurethanes synthesised with using recycled component. Chemical structure and mechanical properties investigations.
PublicationThis paper aims at the utilisation of glycerolysate (Gly) obtained in polyurethane recycling process by means of crude glycerine, which has in its structure hydroxyl end groups that allow for further processing. Polyurethanes (PUs) were synthesised using prepolymer method with the mixture of neat polyol and glycerolysate, in different ratios, with 4,4-diphenylmethane diisocyanate (MDI). The prepolymer was subsequently extended...
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Porous structures in aspects of transpirating cooling of oxycombustion chamber walls
PublicationA wet oxycombustion chamber, which must be effectively cooled due to high temperature evolved during the oxy-combustion process, by using the phenomena of Reynolds thermal transpiration and Navier slip velocity. Closures needed to execute mass flow rate in a microchannel, which should be treated as a single porous structure in the walls of the combustion chamber, have been obtained by applying a local 3D approach. The Navier-Stokes...
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Kinetics of molecular decomposition under irradiation of gold nanoparticles with nanosecond laser pulses—A 5-Bromouracil case study
PublicationABSTRACT Laser illuminated gold nanoparticles (AuNPs) efficiently absorb light and heat up the surrounding medium, leading to versatile applications ranging from plasmonic catalysis to cancer photothermal therapy. Therefore, an in-depth understanding of the thermal, optical, and electron induced reaction pathways is required. Here, the electrophilic DNA nucleobase analog 5-Bromouracil (BrU) has been used as a model compound to...