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The influence of rubber recyclate morphology on the properties of rubber-asphalt composite
PublikacjaIn the paper wastes, mostly in the form of used tires, were analyzed. One of the methods of waste tires application use them as a modifier of asphalt. However, the properties of rubber-asphalt composites depend on the morphology of waste tiregranulate and kind of tire recycled (car/truck). In this chapter, the influence of grinding methods of waste tire on the prop¬erties of rubber-asphalt composites were studied. SEM analysis...
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Mechanical Properties of a Dike Formed from a Soil-ash Composite
PublikacjaThe paper presents the research results on application of composite soils for dike construction. The composite soil is produced by mixing bottom ash (by-product of energetics) with dredged material (sand) taken from the mouth of The Vistula river. The optimum composite for dike core was chosen with respect to mechanical parameters: high internal friction angle, good compaction and reduced hydraulic conductivity. The test dike was...
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Problems with modelling the strength properties of sailing vessels rigging ropes
PublikacjaThis article presents the basic parameters of soft ropes: natural fibre ropes, soft wire ropes and synthetic fibre ropes used for running rigging. There are only several materials still used for the production of natural fibre ropes, including cotton, jute, hemp, sisal and manila hemp. The most commonly used soft wire ropes are twisted pair ropes; for smaller diameters there is a 6x19M - FC rope and for larger diameters – 6x37M...
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PROPERTIES OF ONE DIMENSIONAL OPEN-CHANNEL STEADY FLOW EQUATIONS
PublikacjaIn this paper properties of discrete forms of one dimensional steady gradually varied flow equations are discussed. Such forms of flow equations are obtained as a result of approximation of their differential forms, which is required to solve them numerically. For such purpose explicit or implicit numerical approximation schemes for ordinary differential equations can be applied. It turns out that dependently on the chosen approximation...
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The impact of natural fibers’ characteristics on mechanical properties of the cement composites
PublikacjaThe paper reviews the properties of cement composites reinforced with short fibres. The effect of natural fibres was investigated: cotton, sisal, jute, ramie, bamboo, and synthetic fibres: polymer and polypropylene. It was noticed that the fibres change the consistency of the mixture up to 15%. In the composite flexural strength tests, a change in strength by +/− 8% was observed, depending on the type of fibres used. The research...
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Vibrational Properties of LaNb0.8M0.2O4-δ (M=As, Sb, V, and Ta)
PublikacjaLaNb0.8M0.2O4-δ (where M=As, Sb, V, and Ta) oxides with pentavalent elements of different ionic sizes were synthesized by a solid-state reaction method. The vibrational properties of these oxides have been investigated. These studies revealed that the substituent element influences both Debye temperature value as well as the Raman active vibrational modes. Additionally, the low-temperature vibrational properties of LaNb0.8Sb0.2O4-δ...
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Dielectric Spectroscopy Studies and Modelling of Piezoelectric Properties of Multiferroic Ceramics
PublikacjaCompounds and solid solutions of bismuth ferrite (BiFeO3)—barium titanate (BaTiO3) system are of great scientific and engineering interest as multiferroic and potential high-temperature lead-free piezoelectric materials. In the present paper, the results of research on the synthesis and characterisation of 0.67Bi1.02FeO3–0.33BaTiO3 (67BFBT) ceramics in terms of crystal structure and dielectric and piezoelectric properties are reported....
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Processing, Mechanical and Morphological Properties of GTR Modified by SBS Copolymers
PublikacjaIn this work, ground tire rubber (GTR) was thermo-mechanically treated in the presence of styrene-butadiene-styrene (SBS) copolymers. During preliminary investigation, the effects of different SBS copolymer grades, the variable content of SBS copolymer on the Mooney viscosity, and the thermal and mechanical properties of modified GTR were determined. Subsequently, GTR modified by SBS copolymer and cross-linking agents (sulfur-based...
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Polyurethane Glycerolysate as a Modifier of the Properties of Natural Rubber Mixtures and Vulcanizates
PublikacjaChemical recycling of polyurethanes can be realized in several different ways, but the most important methods are glycolysis and glycerolysis. Both methods permit recovery of polyols (when the process is realized with the mass excess of depolymerizing agent) or substitutes of polyols, which contain urethane moieties in the main chains and terminate mainly in hydroxyl groups (when the process is realized with the mass excess of...
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Polyglycerol esters of lauric acid with defined hydrophile-lipophile properties.
PublikacjaZsyntetyzowano estrowe pochodne poligliceroli i kwasu laurynowego w obecności laurynianu sodu powstającego in situ. Przeanalizowano wpływ temperatury, stężenia katalizatora oraz czasu reakcji na postęp reakcji polimeryzacji glicerolu, a także wpływ stężenia karboksylanu i czasu reakcji na reakcję estryfikacji uzyskanej mieszaniny polioli kwasem laurynowym. Zauważono, że zastosowana metoda syntezy estrów poligliceroli prowadzi do...
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Sources, properties and suitability of new thermostable enzymes in food processing
PublikacjaW niniejszym artykule przedstawiono przegląd badań wskazujących na przydatność rekombinantowej alfa-amylazy z Pyrococcus woesei i alfa glukozydazy z Thermus thermohilus do jednoetapowego wytwarzania syropów skrobiowych. Rekombinantowa beta-glikozydaza z Pyrococcus woesei może być natomiast stosowana do produkcji bezlaktozowych produktów z mleka i serwatki. Zachowanie aktywności w szerokim zakre-sie pH od 4,3 do 6,6 oraz duża termostabilność...
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Properties of PA6/thermoplastic polyurethane and PA6/polyurethane nanocomposite blends
PublikacjaPrzedstawiono wyniki badań właściwości i struktury mieszanin i nanokompozytów układów PA6/termoplastyczny poliuretan. W przypadku nanokompozytów wprowadzano nanonapełniacz w postaci montmorylonitu. Zbadano właściwości termiczne i wytrzymałościowe oraz omówiono wyniki analiz strukturalnych, otrzymanych z dyfrakcji rentgenowskiej i mikroskopii elektronowej.
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Synthesis, physical and chemical properties of polyetherurethanes modified by natural antioxidant
PublikacjaOtrzymano nowe polieterouretany modyfikowane witaminą E. Ten naturalny przeciwutleniacz związany został z makrocząsteczkami w postaci bocznych odgałęzień poprzez wiązanie eterowe lub uretanowe, zależnie od użytego w syntezie jednego z dwóch rodzajów otrzymanych uprzednio monomerów. Polimery scharakteryzowano mierząc wytrzymałość na rozciąganie i twardość oraz absorpcję wody i oleju słonecznikowego. Odporność chemiczną badano oznaczając...
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Effect of boundary conditions in shear testers on properties of bulk solids.
PublikacjaPrzedstawiono wpływ warunków brzegowych w dwóch różnych aparatach ścinania na wielkość odkształceń i naprężeń. Obliczenia wykonano przy zastosowaniu metody elementów skończonych i mikropolarnego prawa hipoplastycznego.
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Capping ligand initiated CuInS2 quantum dots decoration on, ZnIn2S4 microspheres surface under different alkalinity levels resulting in different hydrogen evolution performance
PublikacjaSurface distribution of quantum dots (QDs) at the semiconductor matrix caused by synthesis condition (e.g. pH of solution during coupling) could lead to different photocatalytic activity. Thus, achieving an optimal covering of semiconductor matrix by QDs has been challenging. Herein, the influence of the alkalinity level of aqueous decoration medium for the coupling of mercaptoundecanoic acid (MUA) capped CuInS2 quantum dots (CIS)...
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Influence of alkali metal cations on the photoactivity of crystalline and exfoliated amorphous WO3 – photointercalation phenomenon
PublikacjaIn order to investigate the effect of photointercalation on photoelectrochemical properties, two types of WO3-based photoanodes, bulk and exfoliated have been prepared and investigated. An aqueous exfoliation method is introduced for the simple fabrication of amorphous and hydrated WO3 nanomaterial using commercial bulk WO3 precursor. The comparison of obtained material with bulk WO3 was performed using Raman, UV–vis, and XPS as...
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Lanthanide-organic-frameworks modified ZnIn2S4 for boosting hydrogen generation under UV–Vis and visible light
PublikacjaNovel Ln-MOF with microrods shape were successfully combined with ZnIn2S4 (ZIS) microsphere and used for photocatalytic hydrogen generation under UV–Vis and visible light. The Ln-MOFs/ZIS system comprises lanthanide-carboxylate coordination networks (Tm and Gd as metal ions, and 1,3,5-benzenetricarboxylic acid (BTC) as the organic linker) deposited on ZnIn2S4 microspheres. Effect of the amount of ((Tm,Gd)-BTC) (1, 5, 10 wt%) on...
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Magnetic photocatalysts for water treatment
PublikacjaThe concept of magnetic photocatalysts with separation function requires ferromagnetic material with high magnetic susceptibility to an external magnetic field to enable recycling of composite nanoparticles. Currently, much attention is devoted to functionalization of photocatalyst using MFe2O3, where M =Fe, Zn, Co, Mn. However direct contact between photocatalyst and magnetic iron oxide particles leads to photodissolution of iron...
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KTaO3-based nanocomposites for air treatment
PublikacjaThe advantage is that photocatalytic methods allow removing VOCs, NOx, SO2, deodorants, and microorganisms at the same system. The new third generation of photoactive materials activated by low powered and low cost irradiation sources (such as LEDs or black fluorescent UV lamps) can be used as photocatalysts in air purification systems. A series of single semiconductors and their nanocomposites combination were prepared using hydrothermal...
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Energy requirements for methods improving gas detection by modulating physical properties of resistive gas sensors
PublikacjaAbstract. One of the most important disadvantage of resistive gas sensors is their limited gas selectivity. Therefore, various methods modulating their physical properties are used to improve gas detection. These methods are usually limited to temperature modulation or UV light irradiation for the layers exhibiting photocatalytic effect. These methods cause increased energy consumption. In our study we consider how much energy...
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Fabrication of ILs-Assisted AgTaO3 Nanoparticles for the Water Splitting Reaction: The Effect of ILs on Morphology and Photoactivity
PublikacjaThe design of an active, stable and ecient photocatalyst that is able to be used for hydrogen production is of great interest nowadays. Therefore, four methods of AgTaO3 perovskite synthesis, such as hydrothermal, solvothermal, sol-gel and solid state reactions, were proposed in this study to identify the one with the highest hydrogen generation eciency by the water splitting reaction. The comprehensive results clearly show that...
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Mono- and bimetallic (Pt/Cu) titanium(IV) oxide core–shell photocatalysts with UV/Vis light activity and magnetic separability
PublikacjaTitanium(IV) oxide is one of the most widely investigated photocatalysts. However, separation of nano-sized particulate titania might result in profitless technologies for commercial applications. Additionally, bare titania is almost inactive under the Vis range of solar spectrum due to its wide bandgap. Therefore, the present study aims to prepare novel coreinterlayer- shell TiO2 magnetic photocatalysts modified with metal nanoparticles...
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Insight into (Electro)magnetic Interactions within Facet-Engineered BaFe12O19/TiO2 Magnetic Photocatalysts
PublikacjaA series of facet-engineered TiO2/BaFe12O19 composites were synthesized through hydrothermal growth of both phases and subsequent deposition of the different, faceted TiO2 nanoparticles onto BaFe12O19 microplates. The well-defined geometry of the composite and uniaxial magnetic anisotropy of the ferrite allowed alternate interfaces between both phases and fixed the orientation between the TiO2 crystal structure and the remanent...
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Preparation and Characterization of Au/Pd Modified-TiO2 Photocatalysts for Phenol and Toluene Degradation under Visible Light—The Effect of Calcination Temperature
PublikacjaRutile loaded with Au/Pd nanoparticles was prepared using a water-in-oil microemulsion system of water/AOT/cyclohexane followed by calcination.Theeffect of calcination temperature (from350 to 700∘C) on the structure ofAu/Pd nanoparticles deposited at rutile matrix and the photocatalytic properties of Au/Pd-TiO2 was investigated in two model reactions (toluene degradation in gas phase and phenol degradation in aqueous phase). The...
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The interplay between dopant and a surface structure of the photocatalyst – The case study of Nb-doped faceted TiO2
PublikacjaAnatase nanoparticles, exposing the majority of the {0 0 1}, {1 0 0} and {1 0 1} facets were synthesized and doped with different niobium amount to investigate the self-trapping of the excess electrons and resulting photocatalytic activity. Photocatalyst structure and presence of excess electrons inside the obtained Nb-doped anatase samples was confirmed by the combination of structural and spectroscopic analyses. Only for the...
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Luminescence properties of TeOx gels
Dane BadawczeThe DataSet contains the emission and excitation spectra of TeOx gels. The material was obtained by the sol-gel method. The starting solution was prepared by mixing telluric acid (precursor) with thetraetylene glycol, water, and ethanol. The sol was obtained by vigorously stirring precursor solution at 50°C for 2h, then the temperature was raised...
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KTaO3-based nanocomposites for air treatment
PublikacjaA series of single semiconductors and their nanocomposites combination (such as KTaO3 + CdSe + SrTiO3; KTaO3 + CdS +WO3; KTaO3 + CdS + MoS2) were prepared using hydrothermal route. Photocatalytic activity of as-prepared nanocomposites was estimated by photocatalytic degradation of toluene in the gas phase using light-emitting diodes (LEDs, 375 nm) in four subsequent cycles. The nanocomposites were characterized by scanning electron...
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Monometallic nanoparticles decorated and rare earth ions doped KTaO3/K2Ta2O6 photocatalysts with enhanced pollutant decomposition and improved H2 generation
PublikacjaNew, monometallic nanoparticles (MNPs) decorated surface and rare earth (RE) ions doped lattice of perovskite-type (KTaO3)/pyrochlore-type (K2Ta2O6) photocatalysts were successfully prepared by facile hydrothermal incorporation of RE ions into KTaO3/K2Ta2O6 lattices followed by photodeposition of MNPs. The impact of noble metal type (MNPs = Au, Pt, Rh) and rare earth dopant type (RE = Er, Pr) on the physicochemical properties correlated...
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Antimony substituted lanthanum orthoniobate proton conductor – structure and electronic properties.
PublikacjaX‐ray and neutron diffraction have been utilized to analyze the crystalline and electronic structure of lanthanum orthoniobate substituted by antimony. Using X‐ray absorption spectroscopy and photoelectron spectroscopy, changes in the electronic structure of the material upon substitution have been analyzed. The structural transition temperature between fergusonite and scheelite phases for 30 mol% antimony substitution was found...
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Biological and mechanical properties of bone cement with nanoarticles - in vitro and in vivo research
PublikacjaDespite antibiotic preventive treatment both before and after implant implementation, the risks of infection are real. These infections develop at the implant surface a few months after inserting them into the body. To prevent the development of bacteria and reduce the risk of infection, implants coated with nanoparticles are used. The Mechanical Department of the Technical University of Gdansk carries out research into using bone...
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Determination of the Bending Properties of Wire Rope Used in Cable Barrier Systems
PublikacjaThis paper presents research on the bending properties of 3 × 7 19-mm wire rope commonly used in road cable barriers. A total of 19 experimental tests were conducted. In addition, two nonlinear 3D numerical models of the wire rope using beam and solid finite elements were developed. Based on these models, four numerical simulations were carried out. The numerical results were validated against the experimental ones and a very good...
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Single crystal growth and physical properties of MCo2Al9 (M= Sr, Ba)
PublikacjaSingle crystals of SrCo2Al and BaCo2Al9 were grown using a self-flux method. A LeBail analysis of the powder X-ray diffraction patterns show that both compounds crystallize in a hexagonal (P6/mmm) crystal structure with lattice parameters: a = 7.8995(1) Å, c = 3.9159(1) Å for SrCo2Al9, and a = 7.9162(2) Å, c = 3.9702(1) Å for BaCo2Al9 aluminide. The low temperature analysis of the heat capacity measurements give a Sommerfeld...
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Application of Artificial Neural Networks to Predict Insulation Properties of Lightweight Concrete
PublikacjaPredicting the properties of concrete before its design and application process allows for refining and optimizing its composition. However, the properties of lightweight concrete are much harder to predict than those of normal weight concrete, especially if the forecast concerns the insulating properties of concrete with artificial lightweight aggregate (LWA). It is possible to use porous aggregates and precisely modify the composition...
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Case study of water vapour transmission properties of EPDM façade membranes
PublikacjaThis research aimed to investigate the water vapour transmission properties of chosen EPDM membranes applied in façade and window systems under laboratory tests. The applied procedure included in national and international standards utilized for the laboratory tests of water vapour transmission properties of EPDM membrane is described. Two main types (outside and inside types) of EPDM membranes are laboratory tested. The authors...
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Preparation and Properties of Thermoplastic Polyurethane Composites Filled with Powdered Buckwheat Husks
PublikacjaBio-based fillers for the polymer composites are still interesting from the scientific and industrial point of view, due to their low cost and renewable nature. In this work partially green composites were obtained by the mixing of thermoplastic poly(ester-urethane) with the unmodified and modified (by acetylation) grinded buckwheat husks. Obtained biocomposites were characterized in the terms of their chemical structure (FTIR),...
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Praseodymium Orthoniobate and Praseodymium Substituted Lanthanum Orthoniobate: Electrical and Structural Properties
PublikacjaIn this paper, the structural properties and the electrical conductivity of La1−xPrxNbO4+δ (x = 0.00, 0.05, 0.1, 0.15, 0.2, 0.3) and PrNbO4+δ are presented and discussed. All synthesized samples crystallized in a monoclinic structure with similar thermal expansion coefficients. The phase transition temperature between the monoclinic and tetragonal structure increases with increasing praseodymium content from 500 ◦C for undoped...
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Mechanical Properties of Bio-Composites Based on Epoxy Resin and Nanocellulose Fibres
PublikacjaThe aim of our research was to investigate the effect of a small nanocellulose (NC) addition on an improvement of the mechanical properties of epoxy composites. A procedure of chemical extraction from pressed lignin was used to obtain nanocellulose fibers. The presence of nanoparticles in the cellulose pulp was confirmed by FTIR/ATR spectra as well as measurement of nanocellulose particle size using a Zetasizer analyzer. Epoxy...
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Interline power flow controller - properties and control strategy in dynamic states
PublikacjaHigh-power electronic converter topologies, in such forms as Unified Power Flow Controllers (UPFC), Static Compensators (STATCOM) and Interline Power Flow Controllers (IPFC), have been used to enhance and optimize the use of transmission facilities, under the concept of a flexible ac transmission system (FACTS). In Europe, the anticipated proliferation of distributed-generation (DG) in the near future, driven by governmental initiatives...
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The Influence of Cement Type on Early Properties of Cold In-Place Recycled Mixtures
PublikacjaCold in-place recycling is a commonly used maintenance treatment in rehabilitation of low and medium volume roads in Poland. Typically, two types of binding agents are used—cement and bituminous emulsion (or foamed bitumen).Due to the harsh Polish climate with many freeze/thaw cycles and frequent occurrence of saturated conditions, the used amounts of cement are higher than those commonly used in warmer parts of Europe. While there...
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Eco-Friendly Ether and Ester-Urethane Prepolymer: Structure, Processing and Properties
PublikacjaThis study concerns bio-based urethane prepolymers. The relationship between the chemical structure and the thermal and processing parameters of bio-based isocyanate-terminated ether and ester-urethane prepolymers was investigated. Bio-based prepolymers were obtained with the use of bio-monomers such as bio-based diisocyanate, bio-based polyether polyol or polyester polyols. In addition to their composition, the bio-based prepolymers...
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Biomass-Derived Nitrogen Functionalized Carbon Nanodots and Their Anti-Biofouling Properties
PublikacjaThe prevalence of the antibiotic resistant bacteria remains a global issue. Cheap, sustainable and multifunctional antibacterial membranes are at the forefront of filtrating materials capable of treating multiple flow streams, such as water cleansing treatments. Carbon nanomaterials are particularly interesting objects shown to enhance antibacterial properties of composite materials. In this article, amino-functionalized, photoluminescent...
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Effects of Na+, K+ and B3+ Substitutions on the Electrical Properties of La10Si6O27 Ceramics
PublikacjaDoping of Na and K at La sites and of B at Si site in La10Si6O27 with oxyapatite structure and fabrication of their ceramics were made by the solid-state reaction method. It was found that partial substitution of Na+ and K+ on La sites decreased the sinterability of the La10Si6O27 based ceramics, whereas partial substitution of B3+ on the Si site improved the sinterability. Na+ and K+ substitutions in La10−xNaxSi6O27−x and La10−xKxSi6O27−x...
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Study of nanomechanical properties of (1-y)BST-yMgO thin films
PublikacjaIn the present study thin films of MgO – modified Ba0.6Sr0.4TiO3 (BST60/40) solid solution were prepared by the sol-gel-type chemical solution deposition method on stainless steel substrates. A multilayer spin-coating approach was utilized for the Ba0.6Sr0.4TiO3-MgO thin film deposition with subsequent thermal annealing at T=650-750C. Dried BST60/40-MgO gel powders were studied with thermogravimetric and differential thermal analysis...
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Effects of Na+, K+ and B3+ Substitutions on the Electrical Properties of La10Si6O27 Ceramics
PublikacjaDoping of Na and K at La sites and of B at Si site in La10Si6O27 with oxyapatite structure and fabrication of their ceramics were made by solid-state reaction method. It was found that partial substitution of Na+ and K+ on La sites decreased the sinterability of the La10Si6O27 based ceramics, whereas partial substitution of B3+ on Si site imporved the sinterability. Na+ and K+ substitutions in La10-xNaxSi6O27-x and La10-xKxSi6O27-x...
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Comparison of Properties of the Hybrid and Bilayer MWCNTs—Hydroxyapatite Coatings on Ti Alloy
PublikacjaCarbon 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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Influence of Sn and Pb Ions Substitutions on Dielectric Properties of Barium Titanate
PublikacjaThe results of the microstructural and dielectric measurements of (Ba1-xPbx)(Ti1-xSnx)O3 (BPTSx) (x = 0, 0.05, 0.10, 0.30) polycrystalline samples are presented. The samples were obtained by means of a high temperature synthesis and their expected stoichiometry was confirmed by energy dispersive spectroscopy (EDS) measurements. The dielectric properties of BPTSx were studied with the use of broadband dielectric spectroscopy. The...
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PROCESSING, MECHANICAL AND THERMAL PROPERTIES OF RECYCLED LOW-DENSITY POLYETHYLENE STREAMS
PublikacjaThe recycling of plastics is currently one of the most significant industrial challenges. Due to the enormous amounts of plastic wastes generated by various industry branches, it is essential to look for the potential methods of their utilization. Nevertheless, for the efficient application of recycled materials it is crucial to analyze their performance. Therefore, in presented paper we investigated the processing (melt flow index),...
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Gigantic electro-chemo-mechanical properties of nanostructured praseodymium doped ceria
PublikacjaSome oxygen defective fluorites are non-Newnham electrostrictors, i.e., the electromechanical response does not depend on their dielectric properties. Here, we show gigantic electrostriction in nanocrystalline 25 mol% praseodymium doped ceria (PCO) bulk ceramics. The material was fabricated with a fieldassisted spark plasma sintering (SPS) process from high-purity nanoscale PCO powders (<20 nm). The SPS process consolidates the...
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Investigation of Acoustic Properties of Poroelastic Asphalt Mixtures in Laboratory and Field Conditions
PublikacjaMeasures for the improvement of acoustic conditions in the vicinity of roads include the construction of pavement structures with low-noise surfaces with optimal macrotexture and the highest possible sound absorption coefficient. Laboratory evaluation of acoustic properties of a designed asphalt mixture before its placement in the pavement is a good solution. Currently, the most popular method for the determination of the sound...
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Copolymerization of Styrene and Pentadecylphenylmethacrylate (PDPMA): Synthesis, Characterization, Thermomechanical and Adhesion Properties
PublikacjaThe copolymerization of styrene (St) with a bioderived monomer, pentadecylphenylmethacrylate (PDPMA), via atom transfer radical polymerization (ATRP) was studied in this work.The copolymerization reactivity ratio was calculated using the composition data obtained from1HNMR spectroscopy, applying Kelen-Tudos and Finemann-Ross methods. The reactivity ratio of styrene (r1=0.93) and PDPMA (r2=0.05) suggested random copolymerization...