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Synthesis, microstructure and electrical properties of nanocrystalline calcium doped lanthanum orthoniobate
PublikacjaThe single phase lanthanum orthoniobate with tetragonal structure has been synthesized by the means of mechanosynthesis method. The studies have shown the crystal structure of La0.98Ca0.02NbO4 depends on the synthesis stage. The samples were predominantly in the tetragonal phase with a trace amount of the monoclinic phase. The SEM studies of morphology and microstructure have shown nanocrystallinity of the materials. The Raman...
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A COMPARISON OF WEAR PROPERTIES OF WATER LUBRICATED NBR AND PTFE SLIDING BEARINGS
PublikacjaThe excessive wear of a journal shaft can be caused by many factors, for example, working conditions (e.g., temperaturę, slip speed, the type of lubricant), pressure, the type of material used on the bearings and shafts and their roughness, as well as contamination remaining in the system. This paper presents the roughness profiles co-operating with a rubber (NBR) and polytetrafluoroethylene (PTFE) bushes. The conditions of cooperation...
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Aggregation properties of some zirconium phosphate loaded with dirhenium(III) complexes
PublikacjaOne of the important areas of modern science is the selection of the right forms of drug delivery. Layered inorganic nanoparticles, such as zirconium phosphate, have proven themselves well in this area. The study of the properties of these systems and methods of their preparation makes it possible to determine a rational technology of their manufacture, storage conditions as well as suggest a possible mechanism of therapeutic action....
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Local dynamics of fluids and dielectrics as the foundation of signal-carrying wave properties
PublikacjaThis paper develops an original approach to fundamental problems of classical linear acoustics and electromagnetics, proving a crucial role of doubly-dynamic local properties of a propagation medium in supporting wave-like fields able to carry information signals. The proof is composed of two steps concerning, subsequently, fluid acoustics and dielectric electromagnetics. The first step consists in complementing a common, practically...
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Fabrication and properties of electrode material composed of ordered titania nanotubes and pEDOT:PSS
PublikacjaWe report on the two-stage preparation method of electrode material composed of titania nanotubes and poly(3,4-ethylenedioxythiopene):poly(2-styrenesulphonate) conductive polymer (pEDOT:PSS). Initially, titania nanotube arrays were produced by the anodization process of Ti substrate. Next, the polymer was potentiostatically deposited onto the thermally annealed nanotube arrays from the electrolyte containing monomer and counter...
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Effect of starch fillers on the dynamic mechanical properties of rubber biocomposite materials
PublikacjaIn the paper the results of dynamic mechanical study of the biocomposites containing one of two types of (potato or corn) strach used as fillers in different amount were discussed. The composites were obtained from rubbery mixture containing natural rubber (NR) as a main component. Thermomechanical analyses (by DMA) showed that the used quantity of strach fillers only slightly influence on the glass transition temperature of vulcanizates.
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Determination of Mechanical Properties of P91 Steel by Means of Magnetic Barkhausen Emission
PublikacjaIn this work, an attempt at determination of mechanical properties by means of a method based on magnetic Barkhausen emission measurements was proposed. The specimens made of P91 steel were subjected to creep or plastic flow which were interrupted after a range of selected time periods in order to achieve specimens with an increasing level of strain. Subsequently, measurements of magnetic Barkhausen emission were carried out, and...
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The influence of PET mechanical properties on Stretch Blow Molding (SBM) process
PublikacjaIn the paper it is said about the influence of PET mechanical properties on SBM process parameters changes. The below paper mentions also about the influence of PET orientation and crystallization processes which have a very big influence on mechanical and thermal properties of PET material during SBM process. All mechanical data of PET material and SBM process parameters change in time are been got from collected literature which...
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Methodology for determination of the selected mechanical properties of wood based on cutting tests
PublikacjaFrom kiln-dried spruce wood (with steam) as well as in natural conditions were randomly selected 8 samples. After determining the average dimensions, moisture content and density of the samples they have been cut on the frame sawing machine PRW15M for measurement of cutting power. Based on those results from a linear rela-tionship of cutting power versus feed per toot mechanical properties of wood such as facture toughness and...
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Emulsifi ers from renewable materials: an eco-friendly synthesis and properties
PublikacjaThe focus of this study was the preparation of novel bio based polyglycerol emulsifiers characterized by a one pot synthesis, thus by modified properties with respect to interfacial activity and effectiveness as emulsion stabilizers. The final products of the esterification process, carried out in the presence of carboxylates were used directly as emulsifiers (without purification or fractionation). Polyglycerol emulsifiers obtained...
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The external walls of a passive building: A classification anddescription of their thermal and optical properties
PublikacjaThis paper attempts a new classification of insulating materials from the perspective of their utility in thepro-ecological passive construction industry. The main criterion is the conductivity of thermal and solarenergy. Based on their ability to conduct or block fluxes of thermal and solar energy, six types of insulatingwalls are proposed. On the basis of this criterion there are traditional dividing walls (typical walls, wallinsulating...
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MECHANICAL PROPERTIES OF BOTTOM ASH – DREDGED MATERIAL MIXTURES IN LABORATORY TESTS
PublikacjaBottom ash from EC Gdańsk and dredged material taken from the mouth of The Vistula were mixed to form an engineering material used for dike construction. Mixtures with different bottom ash content were tested in laboratory to determine its basic physical and mechanical properties. The optimum bottom ash–dredged material mixture, built in the corps of the test dike, contains 70% of ash. The optimum bottom ash content in the mixture...
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Effect of Coating Material Properties on Tilting-pad Thrust Bearing Performance
PublikacjaPolymer lined tilting-pad bearings demonstrate many advantages over traditional bearing systems. Bearings with a polymer layer in comparison with a babbitted layer show, for example: lower value of friction coefficient (important during start/stops), higher fatigue strength of the coating, better distribution of the load on individual pads due to lower elasticity of the polymers, wider range of operational temperatures or the ability...
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Mechanical properties of polyvinyl chloride-coated fabric under cyclic tests
PublikacjaThe aim of the present paper is to propose a method of laboratory tests necessary for the identification of mechanical properties of the coated fabric. The material parameters of the coated fabric AF 9032 are specified on the basis of the uniaxial and biaxial tensile tests. For the identification process, the techniques based on the least squares methods are used. Additionally, the uniaxial and biaxial cyclic tests are performed...
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Influence of the internal electrolyte composition on amperometric sulphur dioxide sensor properties
PublikacjaIn this work investigation of an amperometric sulphur dioxide sensor with a liquid electrolyte, a mercury sulphate reference electrode and solid polymer electrolyte (Nafion) covered with gold as a working electrode properties is presented. The main goal of this research is to determine the influence of internal electrolyte composition on the sensor properties. Sensor filled with 1M and 5M sulphuric acid has been studied.
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Preparation, composition and properties of fish silage produced with post-coagulation sludge
PublikacjaPost-coagulation sludge was added to fish fydrolyzates (silage). Silage was prepared using whole sprats. Technology of the process has been modified and sulphuric acid was replaced with phosphoric acid. The objective was to evaleuate the quality of produced silage during storage, particulary the changes of peroxide value and amount of free acids in silage fat.
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Enhanced photocatalytic properties of lanthanide-TiO2 nanotubes: An experimental and theoretical study
PublikacjaA series of Er-, Yb-, Ho-, Tb-, Gd-, Pr-TiO2 nanotubes (RE-NTs) was prepared via an electrochemical method. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–vis absorption, scanning electron microscopy (SEM) and luminescent spectroscopy. The experiments demonstrated that toluene in the gas phase was successfully degraded under visible light (LEDs λmax = 465...
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The effect of tyre rubber grinding method on the rubber-asphalt binder properties
PublikacjaRubber products, especially those used in the automotive industry, are responsible for a significant amount of waste, mainly in the form of worn tyres. One way to recycle tyres is to use them as an asphalt binder modifier. The properties of rubber-asphalt binders vary greatly depending on the morphology of the ground tyre rubber (GTR) grains and the type of tyre to be recycled (car/truck). The paper presents the results of research...
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On the influence of shell element properties on the response of car model in crash test
PublikacjaIt goes without saying that numerical simulations play important role in the modern engineering practice. Contemporary CAD environments combined with FEM solvers, along with computer power of modern processors, give the engineer fast and efficient tool. Ultimately, however it is the user alone who is responsible for the correctness of the results. As long as the FEM calculations remain in the sphere of academic exercise, the inevitable...
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Rigid polyurethane foams with different flame retardants and their physical and mechanical properties
PublikacjaRigid polyurethane foams (PUFs) containing 3, 6 or 9 % of one of of two selected fire retardants (FR): oligomeric ethyl ethylene phosphate (Fyrol PNX) and expandable graphite (EG) were prepared, inspected and compared to foam without that fillers as the control. The thermal stability of PUFs was described by horizontal test according to norm: UL 94 HB. Compressive strength and physical properties (density, fragility and water absorption)...
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Influence of anodes fabrication conditions on properties of solid oxide fuel cells
PublikacjaW pracy zamieszczono wyniki badań tlenkowych ogniw paliwowych różniących się warunkami przygotowania anody. Poszczególnego ogniwa różniły się ciśnieniem ściskania, temperaturą spiekania i składem anody.
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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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Electrical properties of Na2O-CaO-P2O5 glasses doped with SiO2 and Si3N4
PublikacjaSodium-calcium-phosphate glasses doped with SiO2 or Si3N4 having similar sodium ion concentrations were prepared by melt quenching. The conductivity was measured by impedance spectroscopy under nitrogen atmosphere in a wide frequency range (10 mHz–1 MHz) and wide temperature range (153–473 K). At 36.6 °C, DC conductivities of all glasses vary between 1.1 ∗ 10−12 and 8.9 ∗ 10−12 S cm−1 and have similar activation energies (between...
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Effect of Semiconductor Element Substitution on the Electric Properties of Barium Titanate Ceramics
PublikacjaThe investigated ceramics were prepared by a solid-state reaction from simple oxides and carbonates with the use of a mixed oxide method (MOM). The morphology of BaTi0.96Si0.04O3 (BTSi04) ceramics was characterised by means of a scanning electron microscopy (SEM). It was found that Si+4 ion substitution supported the grain growth process in BT-based ceramics. The EDS results confirmed the high purity and expected quantitative composition...
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Effects of the Origin and Deacetylation Degree of Chitosan on Properties of Its Coatings on Titanium
PublikacjaThe properties of chitosan coatings on titanium surfaces may be influenced by a variety of factors, including their chemical characteristics and the deposition method. The aim of this research was to determine the influence of a chitosan’s origin (a type of shrimp) and deacetylation degree (DD), when deposited on a very smooth titanium surface, on adhesion and biological behavior. The tests were performed using chitosan of a degree...
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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...
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Experimental and predicted physicochemical properties of monopropanolamine-based deep eutectic solvents
PublikacjaIn this work, the novel deep eutectic solvents (DESs) based on 3-amino-1-propanol (AP) as hydrogen bond donor (HBD) and tetrabutylammonium bromide (TBAB) or tetrabutylammonium chloride (TBAC) or tetraethylammonium chloride (TEAC) as hydrogen bond acceptors (HBAs) were synthesized with different molar ratios of 1:4, 1:6 and 1:8 salt to AP. Fourier Transform Infrared Spectroscopy measurements were performed to provide an evidence...
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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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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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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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Biological and mechanical properties of bone cement with nanoparticles - in vivo and in vitro research
PublikacjaDespite antibiotics preventive treatment, before and after an implant implementation, risk of infection are real. These infections at the implant surface develop in a few months after applying them into the body. To prevent the development of bacteria and to reduce the risk of infection, implants coated with nanoparticles come into use. The Mechanical Department of the Technical University of Gdańsk carried out a research with...
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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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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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Investigation of tracking systems properties in CAVE-type virtual reality systems
PublikacjaIn recent years, many scientific and industrial centers in the world developed a virtual reality systems or laboratories. One of the most advanced solutions are Immersive 3D Visualization Lab (I3DVL), a CAVE-type (Cave Automatic Virtual Environment) laboratory. It contains two CAVE-type installations: six-screen installation arranged in a form of a cube, and four-screen installation, a simplified version of the previous one. The...
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Numerical analysis of mechanical properties of an infill structure used in 3D printings
PublikacjaThe paper presents results of a numerical analysis focused on an identification of mechanical properties of an element created by using Fused Deposition Modelling additive manufacturing technique (FDM). There is presented a description of technology of the 3D printing, numerical model created by using the finite element method (FEM), as well as some problems referred to estimation of the mechanical properties of the printout. The...
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The Effect of Calcination Temperature on Structure and Photocatalytic Properties of WO3/TiO2 Nanocomposites
PublikacjaSeries ofWO3/TiO2 nanocompositeswere obtained by hydrothermal method followed by calcination in the temperature range from 400∘C to 900∘C. The characteristics of photocatalysts by X-ray diffractometry (XRD), scanning electron microscope (SEM), and diffuse reflectance spectroscopy (DRS) showed that increasing the calcination temperature from 400 to 900∘C resulted in change of photocatalytic activity under UV-Vis light.Moreover,...
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Thermal and Mechanical Properties of Microporous Polyurethanes Modified with Reduced Graphene Oxide
PublikacjaMicroporous polyurethanes (MPU) were modified by adding 0.25%–1.25 wt% of reduced graphene oxide (RGO). The materials were prepared without solvent via in situ polymerization. From a technological point of view, it is very important to obtain functional materials by using reacting compounds only. The thermal characteristics of obtained MPU were investigated using TGA, DSC, and DMA techniques. In comparison to nonmodified microporous...
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Structural properties of hypothetical CeBa2Cu3O7 compound from LSDA+DMFT calculations
PublikacjaThe hypothetical stoichiometric CeBa2Cu3O7 (Ce123) compound, which has not been synthesized as a single phase yet, was studied by the density functional theory (DFT). We utilized a method which merges the local spin density approximation (LSDA) with the dynamical mean-field theory (DMFT) to account for the electronic correlations. The LSDA+DMFT calculations were performed in the high-temperature range. The particular emphasis was...
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Signal conditioning for examination of shallow-water acoustic noise correlation properties
PublikacjaThe article describes the process of signal conditioning for examination of acoustic noise correlation properties in shallow water. Knowledge of these properties is very important for the design processes of passive and active hydroacoustic systems. This paper focuses on the above issue from the point of view of passive sonar. In sonar systems, signal processing algorithms operate on both useful acoustic signals, and accompanying...
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Structural and Transportation Properties of Strontium Titanate Composites with Ion Conductive Oxides
PublikacjaThis paper has been written based on the author’s doctoral dissertation “Structural and transportation properties of strontium and titanate composites with ion conductive oxides”, prepared under the supervision of Prof. Dr. Hab. Eng. Bogusław Kusz at the Department of Solid State Physics of Gdańsk University of Technology. It reports the idea of the thesis and conclusions from the study. Niobium doped strontium titanate (Sr(Ti,Nb)O3)...
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Structure and properties of liquid Al–Cu alloys: Empirical potentials compared
PublikacjaWe report on the structure and mass transport properties of liquid Al–Cu alloys predicted by two recently-developed empirical many-body potentials: MEAM (Jelinek et al., 2012) and EAM-ADP (Apostol and Mishin, 2011), and by the well-known Gupta potential. Total and partial pair correlation functions, angular distribution functions, densities, coordination numbers and self-diffusion coefficients are compared with published experimental...
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Periodic Properties of 1D FE Discrete Models in High Frequency Dynamics
PublikacjaFinite element discrete models of various engineering 1D structures may be considered as structures of certain periodic characteristics. The source of this periodicity comes from the discontinuity of stress/strain field between the elements. This behaviour remains unnoticeable, when low frequency dynamics of these structures is investigated. At high frequency regimes, however, its influence may be strong enough to dominate calculated...
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Photovoltaic properties of cadmium selenide–titanyl phthalocyanine planar heterojunction devices
PublikacjaPhotovoltaic phenomenon taking place in cadmium selenide (CdSe)/titanyl phthalocyanine (TiOPc) planar heterojunction devices is described. Mechanisms of free charge carrier generation and their recombination in the dark and under illumination are analyzed, chosen photovoltaic parameters are presented.
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Cold-Active beta-Galactosidases: Sources, Biochemical Properties and Their Biotechnological Potential
Publikacjabeta-D-Galactosidases have been studied extensively in terms of their application to a variety of industrial technologies. To date, considerable research efforts have been devoted to characterization of new cold-active beta-D-galactosidases which were isolated directly from selected species of bacteria and yeasts, as well as with the use of metagenomic approaches. This chapter will provide a review of current research towards cold-active...
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Influence of nanoparticle concentration on thermal properties of thermal oil-MWCNT nanofluid
PublikacjaResults of the measurements of dynamic viscosity, thermal conductivity, electrical conductivity and pH of thermal oil-MWCNT (TO-MWCNT) nanofluid have been presented. Nanoparticles were tested at the concentration of 0.001%, 0.005%, 0.01%, 0.05%, and 0,1% by weight. Thermal oil (TO) was selected as a base liquid, because of possible application in ORC systems as an intermediate heating agent. Multi-walled carbon nanotubes were used...
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In vitro antioxidative and binding properties of phenolics in traditional, citrus and exotic fruits
PublikacjaMany polyphenols bind proteins, therefore our research was focused on the potential of protein binding to polyphenols of investigated fruits and their health-related effects. The contents of polyphenols and related antioxidant activities of traditional, citrus and exotic fruits were compared. The presence of polyphenols (flavonoids and phenolic acids) in the investigated samples and their interaction with human serum albumin (HSA)...
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AN ALTERNATIVE WAY OF DETERMINING MECHANICAL PROPERTIES OF WOOD BY MEASURING CUTTING FORCES
PublikacjaThe cutting force is an energetic effect of splitting material, and might be therefore considered from a point of view of modern fracture mechanics. The dedicated mathematical model developed for description of the wood cutting has been developed here on the base of fracture theory, and includes work of separation (fracture toughness) in addition to the material plasticity and friction. The effect of the cutting edge dullness is...
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THE INFLUENCE OF PET MECHANICAL PROPERTIES ON SBM PROCESS PARAMETERS – LITERATURE REVIEW
PublikacjaIn the paper it is said about the influence of PET (polyethylene terephthalate) mechanical properties on SBM (stretch blow molding) process output parameters changes. The below paper mentions also about the influence of PET orientation and crystallization processes on mechanical and thermal properties of PET material during SBM process. All mechanical data of PET material and SBM process output parameters changes are from collected...
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INFLUENCE OF NANOPARTICLE CONCENTRATION ON THERMAL PROPERTIES OF THERMAL OIL-MWCNT NANOFLUID
PublikacjaThis paper deals with measurements of dynamic viscosity, thermal conductivity, electrical conductivity and pH of thermal oil-MWCNT (TO-MWCNT) nanofluid. Nanoparticles were tested at the concentration of 0.001%, 0.005%, 0.01%, 0.05%, and 0,1% by weight. Ultrasonic vibration was used in order to stabilize the dispersion of the nanoparticles. Thermal oil (TO) was selected as a base liquid, because of possible application in ORC systems...