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High-temperature Co-electrolysis of CO2/H2O and direct methanation over Co-impregnated SOEC. Bimetallic synergy between Co and Ni
PublikacjaTo study the synergy between the transition metals for enhancing the electrochemical and chemical activity, a series of SOECs were modified with a small amount of Co ions, namely 1.8, 3.6, and 5.4 wt% in the reduced state. The addition of βCD into the precursor solution allowed for extremely fine dispersion of Co species across the Ni-YSZ cermet structure. The sample containing 3.6 wt% Co reached an outstanding over 2.5-times-higher...
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Biocompatibility and potential functionality of lanthanum-substituted cobalt ferrite spinels
PublikacjaBulk and nanostructurized lanthanum-cobalt spinels have attracted a lot of interest from researchers, due to their unique physical and chemical properties as well as functionalities, which are interesting for biomedical and electronic industries. In this manuscript we show that introducing small lanthanum (La3+) content can tune magnetic, electronic and cytotoxic properties of the CoFe2− xLaxO4 system (x ≤ 0.1). The mechanisms...
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Experimental tuning of AuAg nanoalloy plasmon resonances assisted by machine learning method
PublikacjaPlasmonic nanostructures based on AuAg nanoalloys were fabricated by thermal annealing of metallic films in an argon atmosphere. The nanoalloys were chosen because they can extend the wavelength range in which plasmon resonance occurs and thus allow the design of plasmonic platforms with the desired parameters. The influence of initial fabrication parameters and experimental conditions on the formation of nanostructures was investigated....
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Current status and future success of renewable energy in Pakistan
PublikacjaMismatch between energy demand and supply from last two decades has been increasing because of the domination of expensive imported oil in energy mix of Pakistan. To import crude oil Government paid US $ 9 billion in 2008–2009 to meet the energy demands...
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Elemental composition, environment of deposition of the Lower Carboniferous Emma Fiord Formation oil shale in Arctic Canada
PublikacjaThe sedimentary succession of 51-m consisting of a thin coal seam (1 m) and oil shale with a marlstone and carbonate-mudstone matrix of the Lower Carboniferous (Viséan) Emma Fiord Formation located on the Grinnell Peninsula, Devon Island, Arctic Canada was examined. The techniques used include reflected light microscopy, and instrumental neutron activation analysis (INAA) for elemental concentration, and inductively coupled plasma...
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Chiral Schiff base complexes as an effective catalyst in Diels-Alder reaction
PublikacjaDiels Alder reaction is a very important tool in carbon-carbon bond formation. It is a cycloaddition between a conjugated diene and a second compound called dienophile. Where one or more heteroatoms are present in the diene and/or dienophile framework, the cycloaddition is called hetero-Diels-Alder reaction (HDA). The asymmetric Diels-Alder reaction is among the most powerful available methodologies for that construction of optically...
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Effect of Tool Positioning Factors on the Strength of Dissimilar Friction Stir Welded Joints of AA7075-T6 and AA6061-T6
PublikacjaFriction Stir Welding (FSW) is a solid-state bonding technique. There are many direct and indirect factors affecting the mechanical and microstructural properties of the FSW joints. Tool offset, tilt angle, and plunge depth are determinative tool positioning in the FSW process. Investigating the effect of these factors simultaneously with other parameters such as process speeds (rotational speed and translational speed) and tool...
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Contemporary and Conventional Passive Methods of Intensifying Convective Heat Transfer—A Review
PublikacjaThe ever-increasing demand for effective heat dissipation and temperature control in industrial and everyday applications highlights a critical research problem. The need for development is not only in terms of providing thermal comfort to humans but also forms the basis for the efficient operation of machines and equipment. Cooling of industrial machinery and household electronic equipment is a crucial element in any manufacturing...
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Biological responses to environmental contamination. How can metal pollution impact signal honesty in avian species?
PublikacjaEnvironmental pollution, for example with metals, can significantly affect the ecosystem balance leading to severe changes. Biologically active pigments are relevant for the appearance and condition of birds. Melanin and carotenoid particles are the most frequently deposited pigments in avian integument. They are responsible for the majority of colors of bird plumage. The phenotypic expression can be affected by metal contamination....
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Toxicity and chemical analyses of airport runoff waters in Poland
PublikacjaThe aim of this study was to assess the ecotoxicological effects of various compounds in complex airport effluents using a chemical and ecotoxicological integrated strategy. The present work deals with the determination of sum of PCBs, PAHs, pesticides, cations, anions, phenols, anionic, cationic, non-ionic detergents, formaldehyde and metals – as well as TOC and conductivity – in runoff water samples collected from 2009 to 2011...
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Ultrasound-assisted wet-impregnation of Ag–Co nanoparticles on cellulose nanofibers: Enhanced catalytic hydrogenation of 4-nitrophenol
PublikacjaIn this study, a novel nanocomposite of bimetallic Ag–Co nanoparticles supported on cellulose nanofibers (CNFs) was synthesised using the ultrasound-assisted wet-impregnation method for catalytic applications. CNFs were prepared from cellulose acetate using the electrospinning technique. Fourier transform infrared spectroscopy (FTIR) analysis confirmed the successful synthesis of CNFs. Further, scanning electron microscopy (SEM)...
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Prediction of metal deformation due to line heating; an alternative method of mechanical bending, based on artificial neural network approach
PublikacjaLine heating is one of the alternative methods of forming metals and this kind of forming uses the heating torch as a source of heat input. During the process, many parameters are considered like the size of the substrate, thickness, cooling method, source power intensity, the travel speed of the power source, the sequence of heating, and so on. It is important to analyze the factors affecting the...
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Mercury concentration in the sediments as a function of changing climate in coastal zone of Southern Baltic Sea – preliminary results
PublikacjaMercury, despite of its many uses in industry, is also highly toxic. It is highly neurotoxic, and because of the ability of mercury to penetrate placental barrier, in some countries ban on predatory fish consumption (the main route of mercury into human organism) by pregnant women was introduced. There are very little publications describing the consequences of weather anomalies on contaminants cycles. No research was published...
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Lanthanide co-doped TiO2: the effect of metal type and amount on surface properties and photocatalytic activity
PublikacjaPreparation of new rare earth metal-containing TiO2 nanocomposites (Nd3+/Er3+, Nd3+/Eu3+, Eu3+/Ho3+-TiO2) using sol–gel route and their photoactivity under visible and ultraviolet light is reported. The obtained photocatalysts were subsequently characterized by Brunauer–Emmett–Teller (BET) method, UV–Vis diffuse-reflectance spectroscopy (DRS), luminescence spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction...
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Study of the anticancer potential of Cd complexes of selenazoyl-hydrazones and their sulfur isosters
PublikacjaThe biological activity of Cd compounds has been investigated scarce since Cd has been recognized as a human carcinogen. However, the toxicity of cadmium is comparable to the toxicity of noble metals such as Pt and Pd. The paradigm of metal toxicity has been challenged suggesting that metal toxicity is not a constant property, yet it depends on many factors like the presence of appropriate ligands. Studies on anticancer activity...
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Ionic liquids for nano- and microstructures preparation. Part 1: Properties and multifunctional role
PublikacjaIonic liquids (ILs) are a broad group of organic salts of varying structure and properties, used in energy conversion and storage, chemical analysis, separation processes, as well as in the preparation of particles in nano- and microscale. In material engineering, ionic liquids are applied to synthesize mainly metal nanoparticles and 3D semiconductor microparticles. They could generally serve as a structuring agent or as a reaction...
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ANALYSIS OF THE IMPACT OF THE PLANNED SEWAGE DISCHARGE FROM THE ‘NORTH’ POWER PLANT ON THE VISTULA WATER QUALITY
PublikacjaThe paper presents results of analysis of the industrial sewage discharge impact from the ‘North’ Power Plant on the Vistula water quality around 45+330 of the river kilometer. For the analysis, the two-dimensional models of flow, impurities and temperature transport were used. Hydrological conditions of the analyzed section of the river, characteristic flows and bathymetry of the riverbed in the first instance were defined....
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Synthesis of CoFe2O4 Nanoparticles: The Effect of Ionic Strength, Concentration, and Precursor Type on Morphology and Magnetic Properties
PublikacjaThe present study highlights the effect of metal precursor types (SO4 2¯, Cl¯, and NO3¯), their concentration, and the influence of ionic strength of reaction environment on the morphology, surface, and magnetic properties of CoFe2O4 particles. The magnetic nanoparticles were obtained by chemical coprecipitation in alkaline medium at increasing metal concentration in the range of 0.0425 mol·dm-3 to 0.17 mol·dm-3 and calcination...
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The impact of sediment, fresh and marine water on the concentration of chemical elements in water of the ice-covered lagoon
PublikacjaThe common use of chemical elements by man has been contributing to their extraction for centuries. As a consequence, they have been directly or indirectly introduced into the biogeochemical cycle. In the framework of many conventions, mining and processing of elements are currently subject to many restrictions. However, their large load that has already been deposited in the soil and bottom sediments can be remobilised and...
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Multi Parameter Sliding Test Result Evaluation for The Selection of Material Pair for Wear Resistant Components of a Hydraulic motor Dedicated for Use With Environmentally Friendly Working Fluids
PublikacjaIn the paper the method and results are presented of the testing of tribological performance of a number of hard materials available commercially. The tests consisted in unidirectional sliding with liquid lubrication. The load and velocity regime chosen were similar to a standard four-ball lubricity test with constant velocity and load increasing over time. The regime was modified in such a way that over the initial part of the...
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Lead In drinking water: Adsorption method and role of zeolitic imidazolate frameworks for its remediation: A review
PublikacjaDue to various characteristics properties lead(II) metal is utilized in many applications like lead ion batteries, water pipes, ammunition and paints. For this reason, concentration of lead(II) ions in water is increasing days by days which is alarming for water pollution. Water pollution is a major problem worldwide which affects biosphere badly, and causes continuous reduction of accessible sources of fresh water and ground water, available...
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Hybrid systems using hydrodynamic cavitation/ultrasound/Fenton processes for effective treatment of wastewater
PublikacjaThe present situation of rapid growth in industrialization generates complex recalcitrant pollutants that are challenging to degrade by conventional wastewater treatment processes. The new generation pollutants such as non-metals in cosmetics or household cleaning chemicals and radioactive compounds which are recalcitrant are the emerging threat to the ecosystem. The headstrong micro and macro pollutants present in wastewater are...
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Functionalized nanodiamonds as a perspective green carbo-catalyst for removal of emerging organic pollutants
PublikacjaRapid industrial and urban development jointly with rising global population strongly affect the large-scale issues with drinking, groundwater, and surface water pollution. Concerns are not limited to environmental issues but also human health impact becoming serious global aspect. Organic pollution becomes a primarily serious hazard, therefore, the novel sophisticated approaches to treat them are thoroughly investigated. Among...
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Green engineered biomaterials for bone repair and regeneration: Printing technologies and fracture analysis
PublikacjaDespite the exceptional self-regeneration properties of bone, severe injuries often require additional surgical intervention such as using artificial bone constructs. These structures need to meet a number of criteria regarding their structure, performance, alongside the rate and the mechanism of erosion and fracture when implanted, for stimulating the regeneration of defected bone and, more critically providing support in the...
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Polish FDI in Central Asian Countries
PublikacjaSince gaining independence, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan gradually opened their markets to foreign investors. Before Poland’s accession to the European Union, the activities of Polish investors in Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan were based on bilateral treaties concluded by Poland with those countries. Later, except Turkmenistan, they were governed by the partnership...
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Assessment of cytotoxic and endocrine potential of selected xenobiotics commonly present in food products
PublikacjaMore and more increased intensity of anthropopressure processes can be observed, among other things, in the release of great quantities of synthetic substances into the environment, including the Endocrine Disrupting Compounds (EDC). A vast number of chemical substances is considered to belong to the this group, including substances which occur naturally in the environment, such as mycotoxins and phytoestrogens, and substances...
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Estimating the Impact of Inflow on the Chemistry of Two Different Caldera Type Lakes Located on the Bali Island (Indonesia)
PublikacjaThis paper is a preliminary attempt to assess the composition of pollutants in two different caldera lakes situated in the Indonesian Archipelago: Batur and Bratan. Both lakes are characterized by largely different physico-chemical regimes; Batur Lake is located in an area that is currently volcanically active, unlike Bratan Lake. The latter is much smaller and shallower than Batur Lake. The concentration of pollutants in the Indonesian...
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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)
PublikacjaAbstract 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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In-depth characterization of icosahedral ordering in liquid copper
PublikacjaThe presence of icosahedral ordering in liquid copper at temperatures close to the melting point is now well-established both experimentally and through computer simulation. However, a more elaborate analysis of local icosahedral and icosahedron-like structures, together with a system for classifying such structures based on some measure of "icosahedrity", has so far been conspicuously absent in the literature. Similarly, the dynamics...
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The importance of CEFTA 2006 for Western Balkan countries
PublikacjaFree foreign trade is one of the most important issues all over the world. The impact of bilateral trade can be studied both from economic as well as political perspectives; when it improves economic development, it also creates the conditions for international stability. The aim of the article is to conduct a comparison of the changes to export trade flow in the Central European Free Trade Agreement 2006, with reference to countries...
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A High-Arctic flow-through lake system hydrochemical changes: Revvatnet, southwestern Svalbard (years 2010–2018)
PublikacjaLake ecosystems are strongly coupled to features of their surrounding landscapes such as geomorphology, lithology, vegetation and hydrological characteristics. In the 2010–2018 summer seasons, we investigated an Arctic flow-through lake system Revvatnet, located in the vicinity of the coastal zone of Hornsund fjord in Svalbard, characterising its hydrological properties and the chemical composition of its waters. The lake system...
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Iridium 5d -electron driven superconductivity in ThIr3
PublikacjaA polycrystalline sample of superconducting ThI r 3 was obtained by arc-melting Th and Ir metals. Powder x-ray diffraction revealed that the compound crystalizes in a rhombohedral crystal structure (R-3m, s.g. #166) with the lattice parameters: a = 5.3394 ( 1 ) Å and c = 26.4228 ( 8 ) Å . Normal and superconducting states were studied by magnetic susceptibility, electrical resistivity, and heat capacity measurements. The results...
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Spatial Differences in the Chemical Composition of Surface Water in the Hornsund Fjord Area: A Statistical Analysis with A Focus on Local Pollution Sources
PublikacjaSurface catchments in Svalbard are sensitive to external pollution, and yet what is frequently considered external contamination may originate from local sources and natural processes. In this work, we analyze the chemical composition of surface waters in the catchments surrounding the Polish Polar Station in Svalbard, Hornsund fjord area. We have pooled unpublished and already published data describing surface water composition...
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Electrochemical cobalt oxidation in chloride media
PublikacjaThe 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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Monitoring strategy for industrially contaminated rivers - A study of all year round behaviour of Klodnica river catchment, upper Silesia, Poland
PublikacjaThe study was undertaken to thoroughly characterise the contamination of water in industrially influenced river Klodnica, in order to explore monitoring strategies in case of limited analytical capacity. Statistical analysis undertaken after a short study was found to be helpful in reducing monitoring efforts in the future.Klodnica river is located within area of dominating coal mining, metallurgy, and additionally being influenced...
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Influence of Different Nanometals Implemented in PMMA Bone Cement on Biological and Mechanical Properties
PublikacjaCemented arthroplasty is a common process to fix prostheses when a patient becomes older and his/her bone quality deteriorates. The applied cements are biocompatible, can transfer loads, and dampen vibrations, but do not provide antibacterial protection. The present work is aimed at the development of cement with antibacterial effectivity achieved with the implementation of nanoparticles of different metals. The powders of Ag,...
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Electrochemical determination of neurotransmitter serotonin using boron/nitrogen co-doped diamond-graphene nanowall-structured particles
PublikacjaElectrode fouling is a major issue in biological detection due to the adhesion of the protein itself and polymerization of biomolecules on the electrode surface, impeding the electron transfer ability and decreasing the current response. To overcome this issue, the use of anti-fouling material, especially boron-doped diamond (BDD) electrode, is an alternative way. However, the electrocatalytic activity of BDD is inadequate compared...
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Ni-WC/Al2O3 and Ni-WC/MgWO4/MgAl2O4 catalysts for resource recovery via pyrolysis combined with the dry reforming of plastics (PCDR)
PublikacjaPlastic waste (PW) is currently one of an environmental threat. Despite the increasing share of recycled plastics, their disposal remains high. Therefore, there is a high demand for new PW management systems. Among them, pyrolysis combined with dry reforming (PCDR) is an advantageous solution because it allows for resource recovery in the form of gas and liquid fuels, with simultaneous utilization of CO2. To date, catalysts based...
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New kagome prototype materials: discovery of KV3Sb5, RbV3Sb5, and CsV3Sb5
PublikacjaIn this work, we present our discovery and characterization of a new kagome prototype structure, KV3Sb5. We also present the discovery of the isostructural compounds RbV3Sb5 and CsV3Sb5. All materials exhibit a structurally perfect two-dimensional kagome net of vanadium. Density-functional theory calculations indicate that the materials are metallic, with the Fermi level in close proximity to several Dirac points. Powder and single-crystal...
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Structural investigations of niobium-doped bioactive calcium-phosphate glass-ceramics by means of spectroscopic studies
PublikacjaSynthetic calcium-phosphate based glasses and glass-ceramics play a crucial role in the development of tissue engineering. These materials have a high biocompatibility with biological analogues, excellent ability to undergo varying degrees of resorbability and due to their non-toxicity and relatively high bioactivity they are commonly used as bone and dental implants. A substantial research effort is devoted to improve synthetic...
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Optical and photocatalytic properties of rare earth metal-modified ZnO quantum dots
PublikacjaA series of novel ZnO quantum dots modified with rare earth metals was successfully prepared by a simple sol-gel approach. The effects of types (Eu, Er, Tb, Yb, Ho, La) and amounts (from 0.09 to 0.45 mmol) of lanthanides on the optical properties, structural characterization and photocatalytic activity of ZnO/RE QDs were systematically investigated. The X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform...
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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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Temperature-controlled nanomosaics of AuCu bimetallic structure towards smart light management
PublikacjaGold–copper nanostructures are promising in solar-driven processes because of their optical, photocatalytic and photoelectrochemical properties, especially those which result from the synergy between the two metals. Increasing interest in their internal structure, such as the composition or distribution of the Au and Cu as well as the size and shape of the nanoparticles, have developed to define their physicochemical properties. In...
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Challenges in operating and testing loop heat pipes in 500–700 K temperature ranges
PublikacjaThe potential applications of loop heat pipes (LHPs) are the nuclear power space systems, fuel cell thermal management systems, waste heat recovery systems, medium temperature electronic systems, medium temperature military systems, among others. Such applications usually operate in temperature ranges between 500–700 K, hence it is necessary to develop an LHP system that will meet this requirement. Such a thermal management device...
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From ashes to porous hierarchical nanocarbon electrode: Upcycling secondary waste materials through self-catalytic chemical vapour deposition
PublikacjaMetal and metal oxide particles are abundant in various ash-based wastes. Utilizing these as catalyst sources for the fabrication of carbon nanomaterials could present a valuable approach to reduce our reliance on non-renewable and costly catalyst sources, thereby facilitating large-scale nanomaterial production. In this context, secondary waste materials (SWMs) are by-products resulting from the (complete or partial) combustion...
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Rainwater chemistry composition in Bellsund: Sources of elements and deposition discrepancies in the coastal area (SW Spitsbergen, Svalbard)
PublikacjaDiscrepancies in rainfall chemistry in Bellsund were found to be influenced by the orographic barrier and related to the variability in the inflow of air masses as well as to the distance of sampling sites from the sea and thus the extent of sea spray impact. This study covers measurements of rainfall (P) and air temperature (T), physicochemical parameters (pH, specific electrolytic conductivity (SEC), major ions (Cl , NO3 , SO4...
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ENVIRONMENTALLY FRIENDLY MATERIALS IN ARCHITECTURE � MODERN TRENDS AND DEVELOPMENT DIRECTIONS
PublikacjaFor a long time the interest in environmentally friendly materials in architecture is no longer limited to the use of renewable and natural substances such as wood, stone, straw, or reusable materials, such as metals or glass. Today the so-called naturals and the materials compatible with the idea of sustainability constantly appear on the market in new forms. Increasing awareness of the necessity to limit the building sector’s...
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Damage detection in 3D printed plates using ultrasonic wave propagation supported with weighted root mean square calculation and wavefield curvature imaging
Publikacja3D printing (additive manufacturing, AM) is a promising approach to producing light and strong structures with many successful applications, e.g., in dentistry and orthopaedics. Many types of filaments differing in mechanical properties can be used to produce 3D printed structures, including polymers, metals or ceramics. Due to the simplicity of the manufacturing process, biodegradable polymers are widely used, e.g., polylactide (polylactide...
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A Multi Rig Screening Test for Thin Ceramic Coatings in Bio - Tribological Applications
PublikacjaA method is presented for the comparative testing of wear resistance of ceramic coatings made from materials potentially feasible in tribo - medical applications, mainly orthopaedic implants made from ceramics coated metals for low cost, long life and low wear particle emission into the body. The method was devised as the main tool for use in research and is comprised of flat on flat and ball on flat surface (sliding) tests. Seven...
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Phytoextraction and recovery of rare earth elements using willow (Salix spp.)
PublikacjaSoil and water contaminations are caused by rare earth elements (REEs) due to mining and industrial activities, that threaten the ecosystem and human health. Therefore, phytoremediation methods need to be developed to overcome this problem. To date, little research has been conducted concerning the phytoremediation potential of Salix for REEs. In this study, two Salix species (Salix myrsinifolia and Salix schwerinii) and two Salix...