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Investigation on the Sources and Impact of Trace Elements in the Annual Snowpack and the Firn in the Hansbreen (Southwest Spitsbergen)
PublikacjaWe present a thorough evaluation of the water soluble fraction of the trace element composition (Ca, Sr, Mg, Na, K, Li, B, Rb, U, Ni, Co, As, Cs, Cd, Mo, Se, Eu, Ba, V, Ge, Ga, Cr, Cr, P, Ti, Mn, Zr, Ce, Zn, Fe, Gd, Y, Pb, Bi, Yb, Al, Nb, Er, Nd, Dy, Sm, Ho, Th, La, Lu, Tm, Pr, Tb, Fe, In, Tl) and their fluxes in the annual snowpack and the firn of the Hansbreen (a tidewater glacier terminating in the Hornsund fjord, southwest...
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Seeding enhancement for microcrystaline diamond layers growth on non-diamond substrates
PublikacjaThe present paper gives an overview on the possible methods of seeding substrates for diamond layers growth. Diamond in reason of his properties is very desirable material in microelectronic, biomedical and waste treatment sensors. Microcrystalline diamond for these applications must be grown on silicon substrate in microwave plasma assisted chemical vapor deposition (MPACVD). To grow diamond on non-diamond surface pre-growth...
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Effect of Particle Size of Fly Ash Microspheres (FAMs) on the Selected Properties of Concrete
PublikacjaThis paper presents the investigations of selected properties of concrete containing two fractions of fly ash microspheres (FAMs) with grain size up to 200 μm and up to 500 μm. Concrete mixtures with ordinary Portland cement and three substitution rates of cement by FAMs, 1.3%, 2.0%, and 2.6%, were investigated. For all concrete mixes, the constant water–binder ratio (w/b) equal to 0.50 was used. The research program included the...
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Comprehensive Evaluation of the Biological Properties of Surface-Modified Titanium Alloy Implants
PublikacjaAn increasing interest in the fabrication of implants made of titanium and its alloys results from their capacity to be integrated into the bone system. This integration is facilitated by different modifications of the implant surface. Here, we assessed the bioactivity of amorphous titania nanoporous and nanotubular coatings (TNTs), produced by electrochemical oxidation of Ti6Al4V orthopedic implants’ surface. The chemical composition...
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Recycling of Polyurethanes Containing Flame-Retardants and Polymer Waste Transformed into Flame-Retarded Polyurethanes
PublikacjaThe growing number of polyurethanes (PUs) produced every year has developed methods for their mechanical and chemical recycling which yield valuable products like substitutes for commercial polyols or flame-retardants. PUs can be produced in different shapes and forms (i.e., elastomers, flexible or rigid foams, coatings, etc.) using several different components (i.e., di- or polyisocyanates, ester- or ether-based polyols, low-molecular...
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Structural properties of mixed conductor Ba1−xGd1−yLax+yCo2O6−δ
PublikacjaBa1−xGd1−yLax+yCo2O6−δ (BGLC) compositions with large compositional ranges of Ba, Gd, and La have been characterised with respect to phase compositions, structure, and thermal and chemical expansion. The results show a system with large compositional flexibility, enabling tuning of functional properties and thermal and chemical expansion. We show anisotropic chemical expansion and detailed refinements of emerging phases as La is...
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Quality of bottled waters
PublikacjaBottled water is a product that is purchased by annually increasing numbers of people of all age groups. The quality control of mineral waters tends to concentrate on the determination of anion and cation levels, since it is these that govern the taste, smell and possible medicinal properties of the water. The constantly rising sales of mineral waters bring with them the ever increasing exploitation of their sources. The consequences...
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MXene-based materials for removal of antibiotics and heavy metals from wastewater– a review
PublikacjaAs a novel family of 2D materials, MXenes provide an extensive variety of applications in water and effluent treatment due to their distinctive properties and attractive applicability, including superior electrical conductivity, higher thermal stability, hydrophilicity, and high sorption-reduction capacity. Their excellent sorption selectivity makes them perfect for removing hazardous contaminants. Currently, MXene-based materials...
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Process Control of Biogas Purification Using Electronic Nose
PublikacjaNowadays, biogas produced from landfills and wastewater treatment plants or lignocellulosic biomass is important sustainable and affordable source of energy. Impurities from biogas stream can cause a serious odor problem, especially for residents of areas immediately adjacent to production plants. Therefore, biogas pre-treatment is necessary to protect engines that convert biogas into energy and in order to increase the specific...
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Underwater Acoustic Communications in Time-Varying Dispersive Channels
PublikacjaUnderwater acoustic communication (UAC) system designers tend to transmit as much information as possible, per unit of time, at as low as possible error rate. However, the bit rate achieved in UAC systems is much lower than for wire or radio-communication systems. This is due to disadvantageous properties of the UAC channels, namely the sea and inland waters. Estimation of UAC channel transmission properties is possible within...
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Intermetallic disordered magnet Gd2Pt1.1Ge2.9 and its relation to other AlB2 -type compounds
PublikacjaThe intermetallic germanide Gd 2 Pt 1.1 Ge 2.9 was synthesized using an arc-melting method. The crystal structure was characterized using powder x-ray diffraction, revealing a disordered ternary AlB 2 -type structure (space group P 6 / m m m , No. 191) with lattice parameters a = 4.2092 ( 1 ) Å and c = 4.0546 ( 2 ) Å . Physical properties were investigated by magnetic susceptibility and heat capacity measurements, which...
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Extended phase diagram of RNiC2 family: Linear scaling of the Peierls temperature
PublikacjaPhysical properties for the late-lanthanide-based RNiC2 (R = Dy, Ho, Er, and Tm) ternary compounds are reported. All the compounds show antiferromagnetic ground state with the Néel temperature ranging from 3.4 K for HoNiC2 to 8.5 K for ErNiC2. The results of the transport and galvanomagnetic properties confirm a charge density wave state at and above room temperature with transition temperatures TCDW = 284, 335, 366, and 394 K for...
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Mesoscopic impedance analysis of solid materials surface
PublikacjaSeveral techniques have been developed in order to characterize electrical properties of surfaces in micrometer/nanometer scale. Obtaining of the spatial distribution of sample resistance, capacitance or potential requires separate measurements performed in different scanning modes. On the other hand, analysis of the frequency response of investigated system enables determination of several physical quantities in single measurement...
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Organic photovoltaics - chosen aspects
PublikacjaThere are many types of organic and organic/inorganic (hybrid) photovoltaic devices that possess many beneficial properties over inorganic solar cells. That makes the former suitable for a broad range of applications and hence so much attention is paid to their development. In spite of intensive research carried on this field of science and technology there are still many crucial problems that need to be solved. Extensive knowledge...
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Application of Survey Simulator for Museums
Publikacja“Virtual Museum” is currently a very popular form of presenting museums’ collections of artefacts as well as an approach to archaeological research [1], [2], [3]. The term “virtual” can be understood in many ways – from a simple collection of on-line photographs, through multidirectional viewable panorama pictures, to complete interactive models of the real world, including 3-dimensional (3D) geometry, physical properties and many...
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Remarks on use of the term “deep eutectic solvent” in analytical chemistry
PublikacjaAbout 20 years ago, Abbott and co-workers researched new solvents that were based on mixtures of choline chloride with urea and carboxylic acids and that were liquid at ambient temperature. The term “deep eutectic solvent” (DES) was later adopted for similar mixtures. As DESs have a number of interesting features, they quickly attracted the attention of researchers and found application in various branches of chemical and materials...
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CO2 capture through direct-contact condensation in a spray ejector condenser and T- junction separator
PublikacjaThe design principle underlying the steam condensation and CO2 purification in a gas power plant with a focus on reducing CO2 emissions encompasses the deployment of a spray ejector condenser (SEC) and separator. This innovative system facilitates direct-contact condensation of steam with non-condensable gas (CO2) by inter acting with a spray of subcooled water, seamlessly integrated with a T-junction separator mechanism aimed...
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The Impact of Thermal Stresses on Volume Resistivity: Performance Comparison between TR-XLPE and XLPE Cables
PublikacjaMost failures in electric power cables are attributed to the development of water trees inside the insulating materials. Thus, the development and utilization of Tree Retardant Cross-Linked Polyethylene (TR-XLPE) based cables have recently been given great attention to overcome the treeing issues. TR-XLPE cables use low-density polyethylene compounds suppressing the formation of water trees while retaining excellent electrical,...
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Some geomechanical properties of a biopolymer treated medium sand
PublikacjaSome geomechanical properties of a biopolymer treated medium sand. This paper presents a laboratory assessment of geomechanical properties of sandy soil improved by biopolymer application. Additives (biosubstance) consist of polysaccharides and water. Biosubstance used in the project was xanthan gum, which comes from bacteria Xanthomonas campestris. Triaxial shear compression tests and unconfi ned compression tests were carried...
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Properties of Nanohydroxyapatite Coatings Doped with Nanocopper, Obtained by Electrophoretic Deposition on Ti13Zr13Nb Alloy
PublikacjaNowadays, hydroxyapatite coatings are the most common surface modification of long-term implants. These coatings are characterized by high thickness and poor adhesion to the metallic substrate. The present research is aimed at characterizing the properties of nanohydroxyapatite (nanoHAp) with the addition of copper nanoparticle (nanoCu) coatings deposited on the Ti13Zr13Nb alloy by an electrophoresis process. The deposition of...
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Polaronic and Mott insulating phase of layered magnetic vanadium trihalide VCl3
PublikacjaTwo-dimensional (2D) van der Waals (vdW) magnetic 3d-transition metal trihalides are a new class of functional materials showing exotic physical properties useful for spintronic and memory storage applications. In this article, we report the synthesis and electromagnetic characterization of single-crystalline vanadium trichloride, VCl 3 , a novel 2D layered vdW Mott insulator, which has a rhombohedral structure (R3, No. 148) at...
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Diamond-based protective layer for optical biosensors
PublikacjaOptical biosensors have become a powerful alternative to the conventional ways of measurement owing to their great properties, such as high sensitivity, high dynamic range, cost effectiveness and small size. Choice of an optical biosensor's materials is an important factor and impacts the quality of the obtained spectra. Examined biological objects are placed on a cover layer which may react with samples in a chemical, biological...
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Alternative convolution approach to friction in unsteady pipe flow
PublikacjaIn 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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Nanocrystalline CVD Diamond Coatings on Fused Silica Optical Fibres: Optical Properties Study
Publikacjapre-treatment by dip coating in two detonation nanodiamond (DND) seeding media has been studied. The DND suspension in ethyl alcohol and dispersion of DND in dimethyl sulfoxide (DMSO) with polyvinyl alcohol (PVA) were chosen for the seeding purpose. The grain size distribution of nanodiamond particles in both seeding media was kept at the same level (approximately 1050 nm). After the seeding nanocrystalline diamond lms were deposited...
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Microplastics removal from aqueous environment by metal organic frameworks
PublikacjaThis paper provides an overview of recent research performed on the applications of metal–organic frameworks (MOFs) for microplastics (MPs) removal from aqueous environments. MPs pollution has become a major environmental concern due to its negative impacts on aquatic ecosystems and human health. Therefore, developing effective and sustainable methods for removing them from aqueous environments is crucial. In recent years, MOFs...
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Preparation and characterization of asphaltene based adsorbents for gas-solid adsorption systems
PublikacjaThe dissertation presents results of the experimental research on asphaltene-based adsorbents (support coated with asphaltene layer) for gas-solid adsorption systems, with special reference to volatile organic compounds (VOCs) removal from gas streams. Analysis of gas adsorption properties revealed that asphaltenes isolated from oxidized bitumen have strong affinity toward VOCs. Interactions with target gas molecules, and selectivity...
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Structural and electrical properties of Cr-doped SrTiO 3 porous materials
PublikacjaSeries of single-phase materials with assumed formula SrTi1−xCrxO3 (where x = 0, 1, 4, 6 mol.%) were obtained by sol-gel method. The structure and microstructure of materials were characterised by X-ray diffraction and scanning electron microscopy methods. Moreover, the study of electrical properties and evaluation of chemical stability in CO2/H2O atmosphere was performed by electrochemical impedance spectroscopy and thermogravimery...
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Portable raman spectrometer for maritime security applications
PublikacjaThe fast identification of explosives, narcotics and other chemicals carried on board of ships or transported in containers to the harbors is an important problem of maritime security. Raman spectroscopy is widely used for fast identification of various chemicals. Continuous progress in the field of photonics has resulted in commercial availability of low-power compact Raman spectrometers which can be integrated into portable systems....
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Approaches Towards Better Immunosuppressive Agents
PublikacjaSeveral classes of compounds are applied in clinics due to their immunosuppressive properties in transplantology and the treatment of autoimmune diseases. Derivatives of mycophe-nolic acid, corticosteroids and chemotherapeutics bearing heterocyclic moieties like methotrexate, azathioprine, mizoribine, and ruxolitinib are active substances with investigated mechanisms of action. However, improved synthetic approaches of known drugs...
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Bioactive Ingredients with Health-Promoting Properties of Strawberry Fruit (Fragaria x ananassa Duchesne)
PublikacjaStrawberries (Fragaria x ananassa Duchesne) belong to the berry group and are characterized primarily by delightful sensory properties. Due to their chemical composition, these fruits are a rich source of bioactive compounds that can modify the metabolic and physiological functions of the body. The aim of this work is to present the current state of research on bioactive ingredients found in these fruits in the context of their...
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Klasyfikacja wyrobów tytoniowych z wykorzystaniem elektronicznych nosów
PublikacjaZapobieganie nielegalnej dystrybucji wyrobów tytoniowych w Polsce stanowi poważny problem. Wyroby tytoniowe przemycane do Polski mogą charakteryzować się niższą jakością, wynikającą z wykorzystania surowców gorszego gatunku. Jednym z rozwiązań zmniejszających skalę tego problemu mogą być działania ograniczające przemyt przez granice państwa. Autorzy pracy uważają, że wykorzystanie elektronicznych nosów do rutynowych kontroli przewożonych...
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TaRh 2 B 2 and NbRh 2 B 2 : Superconductors with a chiral noncentrosymmetric crystal structure
PublikacjaIt is a fundamental truth in solid compounds that the physical properties follow the symmetry of the crystal structure. Nowhere is the effect of symmetry more pronounced than in the electronic and magnetic properties of materials—even the projection of the bulk crystal symmetry onto different crystal faces is known to have a substantial impact on the surface electronic states. The effect of bulk crystal symmetry on the properties...
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Closer look into the structures of tetrabutylammonium bromide–glycerol-based deep eutectic solvents and their mixtures with water
PublikacjaIn recent years, deep eutectic solvents (DES) and it’s mixture with water have become more and more attention as green solvents used in chemistry. However, there are only a few theoretical studies on the mechanisms of pure DES and DES-water complex formation. Therefore, the structural properties of tetrabutylammonium bromide–glycerol-based deep eutectic solvents and their mixtures with water have been investigated by means of Molecular...
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Clay-filled starch films. Part I: Effect of clay kind and glycerol concentration on functional properties of composites
PublikacjaThe aim of this work was to improve the mechanical and water barrier properties of composite filmsprepared from starch and clays, plasticized with glycerol at different concentrations. The effects ofhydrophilic Closite Naþand Nanomer PGV were compared with that exerted by organicallymodifiedmorehydrophobicNanofil2 and NanoBent ZR-1. The antimicrobial activity of compositescontaining hydrophobic clays was also investigated. The hydrophilic...
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Modal Analysis of a Steel Radial Gate Exposed to Different Water Levels
PublikacjaWith the increase in water retention needs and planned river regulation, it might be important to investigate the dynamic resistance of vulnerable elements of hydroelectric power plants, including steel water locks. The most frequent dynamic loads affecting hydroengineering structures in Poland include vibrations caused by heavy road and railway traffic, piling works and mining tremors. More destructive dynamic loads, including...
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FAILURE OF MAGNETIC FLUID SEALS OPERATING IN WATER: PRELIMINARY CONCLUSIONS
PublikacjaThe article analyses properties of magnetic fluid seals installed in rotary sealing no des which operate in the utility water environment. Seals of this type have been examined as a possible solution to the problem with ship manoeuvring propulsion sealing. The present analysis bases on laboratory durability tests of magnetic fluid seals expo sed to long - term utility water loads, at different water pressures and shaft revolutions....
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Glass-ceramic joining of Fe22Cr porous alloy to Crofer22APU: interfacial issues and mechanical properties
PublikacjaThis work deals with the joining of porous Fe22Cr ferritic stainless steel to a dense Crofer22APU plate by using a silica-based, Ba-containing glass-ceramic. The chemical and interfacial stability and the mechanical properties of the joints were evaluated before and after thermal ageing at 700 ◦C for 500hrs. The sintering behaviour of the glass was assessed by using heating stage microscopy (HSM) to study the influence of a porous...
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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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Synthesis and structural characterization of bio-based bis(cyclic carbonate)s for the preparation of non-isocyanate polyurethanes
PublikacjaBio-based cyclic carbonates are of significant research interest as monomers for non-isocyanate polyurethane (NIPU) synthesis. This research describes the synthesis of a series of five-membered bis(cyclic carbonate)s using bio-based polyether polyols (PO3G) with different molecular weights (250, 650 and 1000 g mol−1) and carbon dioxide as green feedstocks. The utilization of CO2 as a source of carbon in the chemical reaction is...
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Diversity and distribution of Tardigrada in Arctic cryoconite holes
PublikacjaDespite the fact that glaciers and ice sheets have been monitored for more than a century, knowledge on the glacial biota remains poor. Cryoconite holes are water-filled reservoirs on a glacier’s surface and one of the most extreme ecosystems for microinvertebrates. Tardigrada, also known as water bears, are a common inhabitant of cryoconite holes. In this paper we present novel data on the morphology, diversity, distribution and...
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Overview of Metamaterials-Integrated Antennas for Beam Manipulation Applications: The Two Decades of Progress
PublikacjaMetamaterials (MMs) are synthetic composite structures with superior properties not found in naturally occurring materials. MMs have gained massive attention over the last two decades because of their extraordinary properties, such as negative permittivity and permeability. These materials enable many applications in communication subsystems, especially in the field of antenna design, to enhance gain, bandwidth, and efficiency,...
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Information content of systems as a physical principle
PublikacjaTo explain the conceptual gap between classical and quantum and other, hypothetical descriptions of the world, several principles have been proposed. So far, all these principles have not explicitly included the uncertainty relation. Here we introduce an information content principle ( ICP ) which represents a constrained uncertainty principle. The principle, by taking into account the encoding and decoding properties of a single physical...
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Sustainable synthesis of cyclic carbonates from bio‐based polyether polyol: the structure characterization, rheological behaviour and thermal properties
PublikacjaThe cycloaddition of CO2 to epoxides represents a green efficient method to form bis(cyclic carbonate)s. The main purpose of the work reported in this paper was to examine the effect of the gas flow rate (20, 40, 60 and 100 mL min–1) during carbonation on the conversion yield, chemical structure, rheological behaviour and thermal properties of the prepared compounds. A series of new bis(cyclic carbonate)s was obtained from bio‐based...
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Cough influence on fascia-mesh system built for a hernia repair - an experimental research
PublikacjaAn experimental approach to identify stronger and weaker fixation schemes in laparoscopic ventral hernia repair is presented in the paper. Two types of implants, whose mechanical properties are significantly different and five kinds of connectors are considered. Physical models of operated hernia have been built using those materials and porcine abdominal tissue. The models have been subjected to dynamic impulse load, similar to...
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Slurry Surfacing Mixes on the Basis of Bitumen Modified with Phenol-Cresol-Formaldehyde Resin
PublikacjaSlow-breaking monophase cationic bitumen emulsions have been produced on the basis of bitumen modified with phenol-cresol-formaldehyde resin (PhCR-F). Bitumen emulsions were used as a binder for thin-layer coatings with slurry surfacing mixes (SSM). Physical and technical parameters of modified and unmodified emulsions were determined and analyzed. The optimal compositions of SSM were selected according to the breaking criterion....
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Underwater Local Cavity Welding of S460N Steel
PublikacjaIn this paper, a comparison of the mechanical properties of high-strength low-alloy S460Nsteel welded joints is presented. The welded joints were made by the gas metal arc welding (GMAW)process in the air environment and water, by the local cavity welding method. Welded joints were testedfollowing the EN ISO 15614-1:2017 standard. After welding, the non-destructive—visual, penetrant,radiographic, and ultrasonic (phased array) tests...
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The state of the art in the field of decrease the pollution in the South Baltic area
PublikacjaVarious form of human activity such as maritime transports, industrial activities, busy traffic, intensive farming and animal husbandry can have negative impact on natural marine environment. Baltic Sea catchment area is characterized by the high river water flux and wastewater treatment plants discharges. Additionally, the limited shallow connection to the North Sea results in little water exchange and residence time of approximately...
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Theoretical Model of Acoustic Wave Propagation in Shallow Water
PublikacjaThe work is devoted to the propagation of low frequency waves in a shallow sea. As a source of acoustic waves, underwater disturbances generated by ships were adopted. A specific feature of the propagation of acoustic waves in shallow water is the proximity of boundaries of the limiting media characterised by different impedance properties, which affects the acoustic field coming from a source situated in the water layer “ deformed”...
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Transport properties of aqueous ionic liquid microemulsions: influence of the anion type and presence of the cosurfactant
PublikacjaTransport properties, viz. specific conductivity, dynamic viscosity and apparent diffusion coefficients, were measured as a function of water content in aqueous ionic liquid microemulsions containing 1-butyl-3- methylimidazolium hexafluorophosphate, [BMIM][PF6] and bis(trifluoromethanesulphonyl)imide, [BMIM][Tf2N], stabilized by the nonionic surfactant TX-100, or its mixture with a cosurfactant, i.e. butanol. The investigation covered...
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Application of Ionic Liquids in Amperometric Gas Sensors
PublikacjaThis article presents an analysis of available literature data on metrological parameters of the amperometric gas sensors containing ionic liquids as an electrolyte. Four mechanism types of signal generation in amperometric sensors with ionic liquid are described. Moreover, this article describes the influence of selected physico-chemical properties of the ionic liquids on the metrological parameters of these sensors. Some metrological...