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Wyniki wyszukiwania dla: transition
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Insights into Stoichiometry Adjustments Governing the Performance of Flexible Foamed Polyurethane/Ground Tire Rubber Composites
PublikacjaPolyurethanes (PU) are widely applied in the industry due to their tunable performance adjusted by changes in the isocyanate index—stoichiometric balance between isocyanate and hydroxyl groups. This balance is affected by the incorporation of modifiers of fillers into the PU matrix and is especially crucial for PU foams due to the additional role of isocyanates—foaming of the material. Despite the awareness of the issue underlined...
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BODIPY‐Perylene Charge Transfer Compounds; Sensitizers for Triplet‐Triplet Annihilation Up‐conversion
PublikacjaBODIPY heterochromophores, asymmetrically substituted with perylene and/or iodine at the 2 and 6 positions were prepared and investigated as sensitizers for triplet-triplet annihilation up conversion (TTA-UC). Single-crystal X-ray crystallographic analyses show that the torsion angle between BODIPY and perylene units lie between 73.54 and 74.51, though they are not orthogonal. Both compounds show intense, charge transfer absorption...
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Influence of Surface-Modified Montmorillonite Clays on the Properties of Elastomeric Thin Layer Nanocomposites
PublikacjaIn recent years, polyurethane nanocomposites have attracted more attention due to the massive demand for materials with increasingly exceptional mechanical, optical, electrical, and thermal properties. As nanofillers have a high surface area, the interaction between the nanofiller and the polymer matrix is an essential issue for these materials. The main aim of this study is to validate the impact of the montmorillonite nanofiller...
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A Method for Determination and Compensation of a Cant Influence in a Track Centerline Identification Using GNSS Methods and Inertial Measurement
PublikacjaAt present, the problem of rail routes reconstruction in a global reference system is increasingly important. This issue is called Absolute Track Geometry, and its essence is the determination of the axis of railway tracks in the form of Cartesian coordinates of a global or local coordinate system. To obtain such a representation of the track centerline, the measurement methods are developed in many countries mostly by the using...
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Modelling hydraulic and capillary-driven two-phase fluid flow in unsaturated concretes at the meso-scale with a unique coupled DEM-CFD technique
PublikacjaThe goal of the research was to demonstrate the impact of thin porous interfacial transition zones (ITZs) between aggregates and cement matrix on fluid flow in unsaturated concrete caused by hydraulic/capillary pressure. To demonstrate this impact, a novel coupled approach to simulate the two-phase (water and moist air) flow of hydraulically and capillary-driven fluid in unsaturated concrete was developed. By merging the discrete...
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Analiza kohortowa przyczyn bierności zawodowej osób w wieku 45+
PublikacjaZmiany demograficzne następujące w ostatnich latach w krajach rozwiniętych stawiają nowe wyzwania przed badaczami i praktykami rynku pracy. Jedną z najbardziej zauważalnych konsekwencji „starzenia społeczeństw” jest wydłużenie czasu bierności zawodowej. Jednocześnie w wolniejszym tempie występuje proces wydłużenia czasu aktywności zawodowej. Z punktu widzenia stabilności systemu emerytalnego istotne jest zatem określenie przyczyn...
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Międzysektorowa mobilność zatrudnienia oraz płac a efektywność rynku pracy.
PublikacjaCelem artykułu jest uzyskanie odpowiedzi na pytanie, czy ocenę efektywności funkcjonowania rynków pracy, rozumianej jako zdolność rynków do „oczyszczania się”, można przedstawić za pomocą analizy międzysektorowej mobilności płac oraz zatrudnienia. W połowie lat 90. XX wieku Paul Krugman dowodził, iż negatywne szoki gospodarcze skutkują w krajach europejskich wzrostem bezrobocia, natomiast w USA wzrostem rozpiętości płac. Tymczasem...
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Two-photon double ionization of atoms in attosecond x-ray radiation fields
PublikacjaWe consider two-photon double ionization of helium with 100, 200, and 400 eV excess energy for the two ejected electrons, corresponding to photon energies of 89.5, 139.5, and 239.5 eV, respectively. We focus on the case of ultrashort pulses (two oscillations of the field) and develop an approach to calculate the two-photon transition matrix elements within the lowest order of the time-dependent perturbation theory. One of the...
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Towards sustainable catalyst-free biomass-based polyurethane-wood composites (PU-WC): From valorization and liquefaction to future generation of biocomposites
PublikacjaA substantial aspect of materials engineering lies in the responsible process of designing polymer-based materials. Due to environmental pollution, excessive consumption of natural resources, and increasing environmental awareness of society, there is a massive need for polyurethane (PU) materials with reduced environmental impact. To date, research on catalyst-free polyurethane-wood composites (PU-WC) has demonstrated a huge potential...
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COVID-19 and digital deprivation in Poland
PublikacjaResearch background: The problem of digital deprivation is already known, but the COVID-19 pandemic has highlighted its negative consequences. A global change in the way of life, work and socialisation resulting from the epidemic has indicated that a basic level of digital integration is becoming necessary. During the lockdown, people were forced to use ICTs to adapt to a rapidly changing reality. Current experience with coronavirus...
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Screening stability, thermochemistry, and chemical kinetics of 3-hydroxybutanoic acid as a bifunctional biodiesel additive
PublikacjaThe thermo-kinetic aspects of 3-hydroxybutyric acid (3-HBA) pyrolysis in the gas phase were investigated using density functional theory (DFT), specifically the M06-2X theoretical level in conjunction with the cc-pVTZ basis set. The obtained data were compared with benchmark CBS-QB3 results. The degradation mechanism was divided into 16 pathways, comprising 6 complex fissions and 10 barrierless reactions. Energy profiles were calculated...
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Two-step synthesis of niobium doped Na–Ca–(Mg)–P–Si–O glasses
PublikacjaNiobium doped biosolubility glasses in the Na–Ca–(Mg)–P–Si–O system were prepared by using an untypical two-step synthesis route. The parent glass was melted in air atmosphere at 1350 °C followed by re-melting the glass in Nb crucible with the addition of metallic Mg/Ca powder in the nitrogen atmosphere. The second melting step was carried out at 1450–1650 °C, using an induction furnace. The topography and structure of the obtained...
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Modelling AOB-NOB competition in shortcut nitrification compared with conventional nitrification-denitrification process
PublikacjaIn particular, mainstream deammonification and/or shortened nitrificationdenitrification via nitrite (so-called “nitrite shunt”) is a promising new treatment concept that has the potential to revolutionise how nitrogen removal is achieved at WWTPs. Understanding the role of the AOB/NOB competition in the nitrogen cycle in wastewater treatment systems will change operational strategies of the novel nitrogen removal processes. The...
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Scaling scrum with a customized nexus framework: A report from a joint industry‐academia research project
Publikacjaespite a wide range of scaling frameworks available, large-scale agile transformations are not straightforward undertakings. Few organizations have structures in place that fit the predefined workflows – while once one applies an off-the-shelf framework outside of its prescribed process, guidance quickly runs out. In this paper, we demonstrate how to instantiate a method configuration process using a lightweight experimental approach...
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Financial Consequences of the Introduction of the Fit For 55 on the Example of Poland
PublikacjaIn Europe and in Poland, there is a growing conviction that climate action is a necessity. When creating long-term strategies or making current decisions, companies are increasingly taking into account issues related to sustainable development and reducing CO2 emissions. Following the signing of the Paris Agreement in 2015, countries around the world pledged to reduce greenhouse gas emissions by 2050 so that the average temperature...
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Different design aspects of an Organic Rankine Cycle turbine for electricity production using a geothermal binary power plant
PublikacjaIn recent years, pressure has been growing to increase the share of renewable energy sources in electricity generation, which may offer opportunities for the development of geothermal energy in regions that have been so far considered unprofitable in this respect. One such country currently undergoing an energy transition is Poland in which low-temperature geothermal resources are currently used for district heating and recreation...
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Comprehensive thermodynamic analysis of steam storage in a steam cycle in a different regime of work: A zero-dimensional and three-dimensional approach
PublikacjaDue to the current trends aiming to reduce carbon dioxide emissions by increasing the use of renewable energy sources, changes are required in the operation of coal-fired steam units. The unstable nature of renewable energy sources, depending on weather conditions, means that the amount of energy produced varies and is not always in line with peak demand. To ensure the security and stability of energy supplies in the energy system,...
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Structural and spectroscopic analysis of a new family of monomeric diphosphinoboranes
PublikacjaWe present a series of amino- and aryl(diphosphino)boranes R2PB(R’’)PR’2, where R2P, R’2P = tBu2P, tBuPhP, Ph2P, Cy2P, and R’’ = iPr2N, Ph, which were obtained via the metathesis reaction of iPr2NBBr2 or PhBBr2 with selected lithium phosphides. The structures of isolated diphosphinoboranes were characterized in the solid state and in solution by means of X-ray diffraction and NMR spectroscopy, respectively. The utility of these...
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Properties of Oxygen Vacancy and Hydrogen Interstitial Defects in Strontium Titanate: DFT + Ud,p Calculations
PublikacjaThis work presents extensive theoretical studies focused on the mixed ion-electron transport in cubic strontium titanate (STO). A new approach to the description of this difficult system was developed within the framework of linear-scaling Kohn–Sham density functional theory, as realized in the ONETEP program. The description we present is free of any empirical parameters and relies on the Hubbard U and Hund’s J corrections applied...
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Comprehensive Investigation of Stoichiometry–Structure–Performance Relationships in Flexible Polyurethane Foams
PublikacjaPolyurethane (PU) foams are versatile materials with a broad application range. Their performance is driven by the stoichiometry of polymerization reaction, which has been investigated in several works. However, the analysis was often limited only to selected properties and compared samples differing in apparent density, significantly influencing their performance. In the bigger picture, there is still a lack of comprehensive studies...
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Intense and stable room-temperature photoluminescence from nanoporous vanadium oxide formed by in-ambient degradation of VI3 crystals
PublikacjaVanadium oxides have attracted research interest because their optoelectronic properties make them optically active with room-temperature photoluminescence (PL) emission, which, however, is not sufficiently intense for real applications. For this reason, many nanostructured vanadium oxides are currently fabricated through several precursors and different treatments to improve the PL efficiency and enhance the PL intensity. Herein,...
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Photoresponsive Amide-Based Derivatives of Azobenzene-4,4′-Dicarboxylic Acid—Experimental and Theoretical Studies
PublikacjaAzobenzene derivatives are one of the most important molecular switches for biological and material science applications. Although these systems represent a well-known group of compounds, there remains a need to identify the factors influencing their photochemical properties in order to design azobenzene-based technologies in a rational way. In this contribution, we describe the synthesis and characterization of two novel amides...
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Anionic states of C6Cl6 probed in electron transfer experiments
PublikacjaThis is the first comprehensive investigation on the anionic species formed in collisions of fast neutral potassium (K) atoms with neutral hexachlorobenzene (C6Cl6) molecules in the laboratory frame range from 10 up to 100 eV. In such ion-pair formation experiments, we also report a novel K+ energy loss spectrum obtained in the forward scattering giving evidence of the most accessible electronic states. The vertical electron affinity...
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Release of selected chemical elements from shale drill cuttings to aqueous solutions of different pH
PublikacjaThe effect of pH changes on leachability of light and heavy metals from shale drill cuttings generated from unconventional shale gas production was investigated. Cuttings, being the primary byproduct generated from drilling operations, belong to the potentially hazardous type of wastes due to presence of heavy and radioactive elements and remains of drilling fluid. In this regard, assessment of potentially dangerous components...
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Effect of high loading of titanium dioxide particles on the morphology and selected properties of natural rubber-based composites
PublikacjaThe aim of this work was to prepare and characterize the natural rubber vulcanizates contained different amounts of titanium dioxide particles. At first rubber mixture was prepared using a laboratory two-roll mill and then samples were vulcanized in a hydraulic press. The formulation of rubber mixture and rubber-processing technique is based on our earlier investigations. Materials were obtained at the different titanium dioxide...
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THE APPLICATION EFFECTS OF CONTINUOUS SATELLITE MEASUREMENTS OF RAILWAY LINES
PublikacjaThe paper presents results of satel lite surveying of the railway's rout es, which have been conducted just after starting in Poland (in 2008) the Active Geodesy Network ASG-EU POS. Afterwards it was possible to effectively utilize the GNSS survey ing results for the inventory of the (exploring) railways in service. Already at the beginning of 2009, the research team from Gdansk University of Technology and Naval Academy in Gdynia,...
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CSR knowledge and perception in Polish SMEs: Evidence from the region of Pomerania.
PublikacjaThe concept of CSR was created in the second half of 20th century mostly with respect to large businesses, mostly multinational corporations. Alongside with the renaissance of small and medium-sized enterprises (SMEs), which took place in the seventh decade of 20th centu-ry, we can observe a constant increase in the popularity of research into CSR practices among SMEs. This topic still remains under-researched, especially in transition...
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Electronically Excited States in Solution via a Smooth Dielectric Model Combined with Equation-of-Motion Coupled Cluster Theory
PublikacjaWe present a method for computing excitation energies for molecules in solvent, based on the combination of a minimal parameter implicit solvent model and the equation-of-motion coupled-cluster singles and doubles method (EOM-CCSD). In this method, the solvent medium is represented by a smoothly varying dielectric function, constructed directly from the quantum mechanical electronic density using only two tunable parameters. The...
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Heat treatment effect on Eu3+ doped TeO2-BaO-Bi2O3 glass systems with Ag nanoparticles.
PublikacjaGlass systems of 73TeO2-4BaO-3Bi2O3-2Eu2O3-xAg ( in molar ratio where x= 0, 1, 2, 3) compositions have been successfully synthesized. Silver nanoparticles were obtained with the employment of heat treatment (HT) procedure executed at 350 °C. Glass transition temperatures of different compositions have been determined through DSC measurements. XRD measurement results presented characteristic amorphous halo indicating lack of long...
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Role of the disulfide bond in stabilizing and folding of the fimbrial protein DraE from uropathogenic Escherichia coli
PublikacjaDr fimbriae are homopolymeric adhesive organelles of uropathogenic Escherichia coli composed of DraE subunits, responsible for the attachment to host cells. These structures are characterized by enormously high stability resulting from the structural properties of an Ig-like fold of DraE. One feature of DraE and other fimbrial subunits that makes them peculiar among Ig-like domain-containing proteins is a conserved disulfide bond...
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Structure redetermination, transport and thermal properties of the YNi3Al9 compound
PublikacjaSingle crystals of completely ordered variant of the YNi3Al9 compound were grown by self-flux method with excess of aluminum. The crystal structure of the title compound was redetermined from single crystal X-ray diffraction data. The structure adopts ErNi3Al9 type, space group R32, parameters of the unit cell a = 7.2838(2) Å, c = 27.4004(8) Å. The growth of relatively large single crystals of the YNi3Al9 compound, having completely...
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Debonding of coin-shaped osseointegrated implants: Coupling of experimental and numerical approaches
PublikacjaWhile cementless implants are now widely used clinically, implant debonding still occur and is difficult to anticipate. Assessing the biomechanical strength of the bone–implant interface can help improving the understanding of osseointegration phenomena and thus preventing surgical failures. A dedicated and standardized implant model was considered. The samples were tested using a mode III cleavage device to assess the mechanical...
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Specialization and inequality along the development path: an interindustry analysis.
PublikacjaCelem niniejszej rozprawy doktorskiej jest przeprowadzenie empirycznej analizy procesów zwišzanych ze zmianami w strukturze specjalizacyjnej państw w procesie rozwoju ekonpmicznego oraz zwišzanych z nimi efektami dystrybucyjnymi dotyczšcymi rozkładu płac i dochodu. Rozprawa składa się z czterech częci: I. Employment and export specialization patterns versus GDP per capita performance - unifying approach; II.Determinants of export...
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The Metal-Free Regioselective Deuteration of 2-Methylquinolin-8-ol and 2,5-Dimethylquinolin-8-ol, Spectroscopic and Computational Studies
PublikacjaAbstract: Aim and Background: Introducing deuterium to a molecule is of interest to a wide variety of research, including investigation of reaction mechanisms or kinetics, analysis of drug metabolism, structural elucidation of molecules, and syntheses of isotopically labeled materials used for NMR spectroscopy and medicinal research. Objective: The transition-metal-free regioselective deuteration of 2-methylquinolin-8-ol...
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Synthesis, structure and properties of novel poly(hydroxyurethane)s obtained by non-isocyanate route
PublikacjaNon-isocyanate polyurethanes (NIPUs) can be synthesized by polyaddition of five-membered bis(cyclic carbonate)s and primary diamines. NIPUs are an alternative for the commonly used (in the form of foams, elastomers, coatings or fibers) in the industry polyurethanes obtained using toxic and moisture sensitive diisocyanates, polyols and low-molecular weight chain extenders. The main aim of this work was to synthesize non-isocyanate...
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Oxidation kinetics of Zircaloy-4 alloy at 673 K determined by GDOES technique
PublikacjaOxidation of zirconium alloys is a process that takes place during the operation of nuclear reactors and is essential for assessing the durability of fuel claddings. The present study was aimed to determine the oxidation kinetics of the Zircaloy-4 alloy using GDOES (glow discharge optical emission spectroscopy) at temperature 673 K corresponding to the conditions of use of fuel pellets. The tests were performed on non-oxidized...
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Experimental study of flow boiling pressure drop and heat transfer of R1233zd(E) at moderate and high saturation temperatures
PublikacjaThe paper presents the results of experimental study of flow boiling of R1233zd(E) in minichannel at moderate and high saturation temperatures. The heat transfer coefficient and pressure drop were measured for flow boiling in a stainless steel tube with 2 mm inside diameter and a length of 300 mm. Experiment has been conducted for saturation temperatures ranging from 83 to 145 °C which corresponds to values of reduced pressures...
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An Investigation of Polyamides Based on Isoidide-2,5-dimethyleneamine as a Green Rigid Building Block with Enhanced Reactivity
PublikacjaNovel, semicrystalline polyamides and copolyamides were synthesized from a new carbohydrate-based diamine, namely isoidide-2,5-dimethyleneamine (IIDMA). In combination with 1,6-hexamethylene diamine (1,6-HDA) as well as the biobased sebacic acid (SA) or brassylic acid (BrA), the desired copolyamides were obtained via melt polymerization of the nylon salts followed by a solid-state polycondensation (SSPC) process. Depending on the...
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The effect of metal cluster deposition route on structure and photocatalytic activity of mono- and bimetallic nanoparticles supported on TiO2 by radiolytic method
PublikacjaTiO2 (P25) was modified with small and relatively monodisperse mono- and bimetallic clusters (Ag, Pd, Pt, Ag/Pd, Ag/Pt and Pd/Pt) induced by radiolysis to improve its photocatalytic activity. The as-prepared samples were characterized by X-ray fluorescence spectrometry (XRF), photoluminescence spectrometry (PL), diffuse reflectance spectroscopy (DRS), X-ray powder diffractometry (XRD), scanning transition electron microscopy (STEM)...
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Changes in gene methylation patterns in neonatal murine hearts: Implications for the regenerative potential
PublikacjaBackground The neonatal murine heart is able to regenerate after severe injury; this capacity however, quickly diminishes and it is lost within the first week of life. DNA methylation is an epigenetic mechanism which plays a crucial role in development and gene expression regulation. Under investigation here are the changes in DNA methylation and gene expression patterns which accompany the loss of regenerative potential. Results The...
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Identification and characterization of single-stranded DNA-binding protein from the facultative psychrophilic bacteria Pseudoalteromonas haloplanktis
PublikacjaSingle-stranded DNA-binding protein (SSB) plays an important role in DNA metabolism such as DNAreplication, repair, and recombination, and is essential for cell survival. This study reports on the ssb-likegene cloning, gene expression and characterization of a single-stranded DNA-binding protein of Pseudoal-teromonas haloplanktis (PhaSSB) and is the first report of such a protein from psychrophilic microorganism.PhaSSB possesses...
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Synthesis, crystal structure and cytotoxic activity of ruthenium(II) piano-stool complex with N,N-chelating ligand
PublikacjaA mononuclear compound of the general formula [(η6-p-cymene)RuIICl(2,2′-PyBIm)]PF6 has been synthesized from a bidentate N,N-donor ligand, viz. 2,-(2′-pyridyl)benzimidazole (2,2′-PyBIm) and the corresponding chloro-complex [(η6-p-cymene)Ru(μ-Cl)Cl]2 (precursor). The isolated coordination compound was characterized by IR, UV–vis and 1H, 13C NMR spectroscopies. The single crystal X-ray analysis of the complex reveals that the asymmetric...
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MEASUREMENT AND ANALYSIS OF A FLOOD WAVE PROPAGATION ON THE KACZA RIVER IN GDYNIA IN NORTHERN POLAND
PublikacjaKacza river is located in northern Poland in the neighborhood of the Gulf of Gdansk and the Baltic Sea. A Kacza having length of 15 km and catchment area of 53 km2 collects the water into the Gulf mostly from inhabited and forested areas within the administrative boundaries of the city of Gdynia. On the 14th and 15th of July 2016 in northern Poland on the large area of Tri-City agglomeration (Gdynia, Gdansk and Sopot) total daily...
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Fracture in Asymmetric Bonded Joints
PublikacjaAdhesion was studied in asymmetric bonded joints using fracture mechanics tests. The asymmetric bonded joints consist of two different type and/or thickness materials bonded by an adhesive. Mentions of asymmetric bonded joint tests employed so far are rare in the literature. They are imperfect and therefore are not standardized. Accordingly three new tests were introduced in this work to study bonded joints. The new metrological...
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Ruthenium(II) and Iridium(III) Complexes as Tested Materials for New Anticancer Agents
PublikacjaThe oncological use of cisplatin is hindered by its severe side eects and a very important resistance problem. To overcome these problems, scientists have attempted to design new generation transition-metal anticancer complexes. In this study, we present new complexes, ruthenium(II) [(6-p-cymene)RuCl(py2CO)]PF6 (1), iridium(III) [(5-Cp)IrCl(py2CO)]PF6 (2), and NH4[IrCl4(py2CO)]H2O (3), based on di-2-pyridylketone (py2CO). The prepared...
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Data librarian and data steward – new tasks and responsibilities of academic libraries in the context of Open Research Data implementation in Poland
PublikacjaThesis/Objective – The policy of Open Access (OA) for researching resources in Europe has been implemented for more than 10 years. The first recommendations concerning providing OA to scientific materials were defined during the implementation of the 7th Framework Programme. Introducing another set of recommendations concerning OA to research data was the next stage. The recommendations were transformed into obligations under the...
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Potential Skyrmion Host Fe(IO3)3: Connecting Stereoactive Lone-Pair Electron Effects to the Dzyaloshinskii-Moriya Interaction
PublikacjaMagnetic skyrmions, which are topologically distinct magnetic spin textures, are gaining increased attention for their unique physical properties and potential applications in spintronic devices. Here we present a design strategy for skyrmion host candidates based on combinations of magnetic spin, asymmetric building units having stereoactive lone-pair electrons, and polar lattice symmetry. To demonstrate the viability of the proposed...
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Universities’ journey towards sustainability- systematic literature review
PublikacjaPurpose: This research aims to identify a sustainable university's key features. It is an essential step in tracing the topics discussed in the context of a sustainable university and their evolution in the scientific discourse. Design/methodology/approach: This paper relies on a systematic literature review (SLR) conducted using two scholarly databases: Emerald and Scopus. The timeframe selected by the authors for reviewing the...
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From structure to luminescence investigation of oxyfluoride transparent glasses and glass-ceramics doped with Eu3+/Dy3+ ions
PublikacjaGlasses and glass-ceramics with nominal composition 73 TeO2– 4BaO– 3Bi2O3–18SrF2-2RE2O3 (where RE = Eu, Dy) have been synthesized by conventional melt-quenching technique and subsequent heat treatment at 370 °C for 24 h in air atmosphere. Various Eu3+ to Dy3+ molar ratio have been applied to investigate luminescence properties in both glass and glass-ceramic matrices. Especially, white light emission through simultaneous excitation...
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Epoxy/Ionic Liquid-Modified Mica Nanocomposites: Network Formation–Network Degradation Correlation
PublikacjaWe synthesized pristine mica (Mica) and N-octadecyl-N’-octadecyl imidazolium iodide (IM) modified mica (Mica-IM), characterized it, and applied it at 0.1–5.0 wt.% loading to prepare epoxy nanocomposites. Dynamic differential scanning calorimetry (DSC) was carried out for the analysis of the cure potential and kinetics of epoxy/Mica and epoxy/Mica-IM curing reaction with amine curing agents at low loading of 0.1 wt.% to avoid particle...