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Examination of epigenetic inhibitor zebularine in treatment of skin wounds in healthy and diabetic mice
PublicationDNA methyltransferase inhibitor zebularine was proven to induce regeneration in the ear pinna in mice. We utilized a dorsal skin wound model to further evaluate this epigenetic inhibitor in wound healing. Full-thickness excisional wounds were made on the dorsum of 2 and 10-month-old healthy BALB/c and 3 and 8-month-old diabetic (db/db) mice, followed by topical or intraperitoneal zebularine delivery. Depending on the strain, age,...
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Enhancing Seismic Performance of Semi-rigid Connection Using Shape Memory Alloy Bolts Considering Nonlinear Soil–Structure Interaction
PublicationSteel Moment-Resisting Frames (SMRFs) have their lateral resistance for their rigid connections, while real conditions have shown that the rigidity of a connection depends on the bolts and the end-plate thickness, which may not provide the assumed rigidity in design process. In this research, the main goal is to enhance the semi-rigid connections using shape memory alloy (SMA) bolts and explore their effects on the seismic limit-state...
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Screen-printed Sn-doped TiO2 nanoparticles for photocatalytic dye removal from wastewater: A technological perspective
PublicationTiO2 is widely used as a photocatalyst with a wide band gap, which limited its application. Ion doping and formulating a high-quality screen-printing paste enhance its features. However, the printability of objects for advanced application seems essential nowadays. In this research, the Sn-doped TiO2 nanoparticles were prepared through a sol-gel method followed by calcination at various temperatures of 450 °C, 550 °C, 650 °C, 750...
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The Impact of Drying Conditions on the Surface Color Changes of Pine Wood
PublicationThe article presents the impact of drying process and selected parameters on the color changes on the surface of pine wood (Pinus sylvestris L.). Three predetermined process conditions (modes), mild, normal, and intensive, were investigated. The experiments were conducted using a semi-industrial scale dryer designed at the Gdańsk University of Technology with a loading capacity of 0.55 m3. The drying process was applied to pine...
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Extremal thermal loading of a bifurcation pipe
PublicationThe subject of considerations is a spherical bifurcation pipe of a live steam made of steel P91, which is an element of a block of coal-fired power plant working with a 18K370 turbine. As experience shows, it is a very sensitive element of the boiler pipelines. An extreme work scenario for such a block has been adopted, in which the turbine is shutting down to a warm state three times in 24 hours. This is an action dictated by...
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Metodyka badań rozwojowych nowego typu silników i pomp satelitowych
PublicationResearch and development of new type satellite motors and satellite pumps SM with small geometrical displacement, from 5 to 73 cm3/rev, has been conducted in cooperation with Stosowanie Maszyn company from Katowice (manufacturer of motors and pump SM). The improvement of construction of those machines, especially construction of axial compensation and construction of fluid distribution channels have been the main problem of research...
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CGO FILMS ON YSZ ELECTROLYTE FABRICATED BY SPRAY PYROLYSIS FOR SOFC
PublicationINTRODUCTION Solid oxide fuel cells are one of the fastest developing energy converters. The advancement introduced by research community provides steady state progress is stability and performance of the fuel cells. Significant influence on the cell’s performance and stability is related to cell design. The simplest design just consists of an anode, a solid electrolyte and a cathode. However, in order to improve the properties,...
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Pool boiling of nanofluids on rough and porous coated tubes: experimental and correlation
PublicationThe paper deals with pool boiling of water-Al2O3 and water- Cu nanofluids on rough and porous coated horizontal tubes. Commercially available stainless steel tubes having 10 mm outside diameter and 0.6 mm wall thickness were used to fabricate the test heater. The tube surface was roughed with emery paper 360 or polished with abrasive compound. Aluminium porous coatings of 0.15 mm thick with porosity of about 40% were produced by...
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The oil film parameters of the wankel engine apex seal in aspects of durability of mating elements
PublicationThe Wankel engine is one of only few alternatives to the reciprocating engines. The advantages such as good value of maximum engine power to its mass ratio are still present and can have great sense in selected fields of application, for example General Aviation. Nevertheless the disadvantages of the Wankel engine design have never lost its importance and still pose an obstacle to wider use of the Wankel engine. One of the main...
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Effect of presence of lifting pocket on the THD performance of a large tilting-pad thrust bearing
PublicationHydrostatic assistance is a commonly used method to improve limited load carrying ability of tiltingpad thrust bearings during transient states of operation of vertical shaft hydro-generators. Despite of special hydraulic equipment (as pumps, valves, etc.), it also requires manufacturing of special recesses/pockets at pad sliding surfaces, into which oil is injected under high pressure. It allows to lift the rotor before start-up...
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Effect of irradiation intensity and initial pollutant concentration on gas phase photocatalytic activity of TiO2 nanotube arrays
PublicationWell-organized TiO2 nanotube arrays were fabricated via one-step anodization process. The as-prepared TiO2 nanotubes were characterized by X-ray powder diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS) and scanning electron microscopy (SEM). Photocatalytic activity of obtained photocatalyst was studied in reaction of toluene degradation in the gas phase using low powered and low...
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The mechanisms of degradation of titanium dental implants
PublicationTitanium dental implants show very good properties, unfortunately there are still issues regarding material wear due to corrosion, implant loosening, as well as biological factors—allergic reactions and inflammation leading to rejection of the implanted material. In order to avoid performing reimplantation operations, changes in the chemical composition and/or modifications of the surface layer of the materials are used. This research...
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DETERMINATION OF SEAKEEPING PERFORMANCE FOR A CASE STUDY VESSEL BY THE STRIP THEORY METHOD
PublicationThe increase of seakeeping performance is of particular importance for car and passenger ferries, service ships in the gas and oil extraction industry and offshore wind power farm industry, as well as for special purpose ships (including military applications). In the water areas of the Baltic Sea, North Sea, and Mediterranean Sea, which are characterised by a short and steep wave, the hull shape has a substantial impact on the...
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Exergy and Energy Analyses of Microwave Dryer for Cantaloupe Slice and Prediction of Thermodynamic Parameters Using ANN and ANFIS Algorithms
PublicationThe study targeted towards drying of cantaloupe slices with various thicknesses in a microwave dryer. The experiments were carried out at three microwave powers of 180, 360, and 540 W and three thicknesses of 2, 4, and 6 mm for cantaloupe drying, and the weight variations were determined. Artificial neural networks (ANN) and adaptive neuro-fuzzy inference systems (ANFIS) were exploited to investigate energy and exergy indices of...
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Lateral forces determine dimensional accuracy of the narrow‑kerf sawing of wood
PublicationThe shrinking global forest area limits the supply of industrially usable raw resources. This, in combination with the ever‑increasing consumption of timber due to population growth can lead to the lack of a positive balance between the annual volumetric growth and consumption of wood. An important innovation toward increasing environmental and economic sustainability of timber production is to reduce the volume of wood residues...
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Simultaneous optical and electrochemical label-free biosensing with ITO-coated lossy-mode resonance sensor
PublicationIn this work we discuss a new label-free biosensing device based on indium tin oxide (ITO) overlaid section of a multimode optical fiber fused silica core. The sensor has been used to optical measurements also simultaneously interrogated electrochemically (EC). Due to optimized thickness and optical properties of ITO film, a lossy-mode resonance (LMR) could be observed in the optical domain, where electrical properties of the film...
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A Highly Sensitive Planar Microwave Sensor for Detecting Direction and Angle of Rotation
PublicationThis article presents a technique based on a modified complementary split-ring resonator (CSRR) to detect angular displacement and direction of rotation with high resolution and sensitivity over a wide dynamic range. The proposed microwave planar sensor takes advantage of the asymmetry of the sensor geometry and measures the angle of rotation in terms of the change in the relative phase of the reflection coefficients. The sensor...
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PARAMETERS OF THE ELECTROPHORETIC DEPOSITION PROCESS AND ITS INFLUENCE ON THE MORPHOLOGY OF HYDROXYAPATITE COATINGS. REVIEW
PublicationMetallic materials intended for bone implants should exhibit not only appropriate mechanical properties, but also high biocompatibility. The surface treatment modifications, for example acidic treatment, laser treatment, ion implantation and deposition of highly biocompatible coatings, are practiced. One of the most popular methods of surface modification is to deposit hydroxyapatite (HAp) coatings. HAp naturally occurs in human...
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A new hyperbolic-polynomial higher-order elasticity theory for mechanics of thick FGM beams with imperfection in the material composition
PublicationA drawback to the material composition of thick functionally graded materials (FGM) beams is checked out in this research in conjunction with a novel hyperbolic‐polynomial higher‐order elasticity beam theory (HPET). The proposed beam model consists of a novel shape function for the distribution of shear stress deformation in the transverse coordinate. The beam theory also incorporates the stretching effect to present an indirect...
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Thermal and economic investigation of straight and U-bend double tube heat exchanger with coiled wire turbulator
PublicationExperimental research has been carried out for four individual heat exchanger constructions, i.e., plain double tube, turbulized double tube, plain U-bend and U-bend with turbulator. Tests were made for the water-water system. The study covered a wide measuring range, i.e., Re = 800–9000 – on the shell side, for a constant cold water temperature of 9 ◦C and hot water of 50 ◦C. The heat exchangers were made from copper tubes with...
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Rapid development of the photoresponse and oxygen evolution of TiO2 nanotubes sputtered with Cr thin films realized via laser annealing
PublicationRecently, earth abundant transition metal oxides have gained particular attention as potential catalyst candidates due to their availability and low-cost comparing to substrates containing precious Pt or Au species. Herein, we present characterization of morphology, structure and electrochemical properties of pulsed 532 nm laser treated TiO2 nanotubes (NT) sputtered by the thin film of chromium. Scanning electron microscopy enables...
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On the generalized model of shell structures with functional cross-sections
PublicationIn the present study, a single general formulation has been presented for the analysis of various shell-shaped structures. The proposed model is comprehensive and a variety of theories can be used based on it. The cross-section of the shell structure can be arbitrarily analyzed with the presented equations. In other words, various types of shell structures, including cylindrical, conical, spherical, elliptical, hyperbolic, parabolic,...
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Electrochemical and photoelectrochemical properties of the interface between titania nanotubes covered by conducting polymer in aqueous by conducting polymer in aqueous electrolytes – The effect of various geometry and electrolytes concentration
PublicationIn the present work we show the impact of nanotubes (NTs) geometry of titania utilized as a substrate in organic-inorganic systems acting as a p-n junction on efficient conversion of radiation energy into electrochemical energy. The electrolytic bath composition and electrolysis conditions were controlled in order to obtain TiO2NTs of various geometry as a result of electrochemical oxidation of titanium foil. The electrode material...
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Decision support system for design of long distance heat transportation system
PublicationDistrict Heating (DH) systems are commonly supplied using local heat sources. Nowadays, modern insulation materials allow for effective and economically viable heat transportation over long distances (over 20 km). The paper proposes a Decision Support System (DSS) for optimized selection of design and operating parameters of a long distance Heat Transportation System (HTS). The method allows for evaluation of feasibility and effectiveness...
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TiO 2 Co x O y composite nanotube arrays via one step electrochemical anodization for visible light–induced photocatalytic reaction
PublicationTiO2CoxOy (x = 1, y = 1 or x = 3, y = 4) composite photocatalysts have been synthesized via one step anodic anodization of TiCo alloys. The effects of the cobalt content in the alloy (5, 10 and 15 wt%), water content (2, 5 and 10%) in the electrolyte solution, and applied voltage (30, 40 and 50 V) during the anodization process on the morphology and surface properties. Additionally, the dependence of cobalt content in the nanotubes...
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Keratin-Butyrate Scaffolds Promote Skin Wound Healing in Diabetic Rats Through Down-Regulation of IL-1β and Up-Regulation of Keratins 16 and 17
PublicationImpaired wound healing particularly in diabetics creates a significant healthcare burden. The study aimed to evaluate the effect of keratin-butyrate fibers (FKDP +0.1%NaBu) in a full-thickness skin wound model in 30 diabetic rats. Physicochemical examination showed that the obtained dressing possesses a heterogeneous structure and butyrate was slowly released into the wound. Moreover, the obtained dressing is nontoxic and supports...
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Electro-optical transducer based on indium-tin-oxide-coated optical fiber for analysis of ionized media
PublicationThe paper introduces a concept of an optical fiber based electro-optical transducer for monitoring of ionized media, such as low-temperature plasma. It utilizes optical fiber with a section of a core coated with tailored indium tin oxide (ITO) thin film and thus combines the optical phenomena of lossy-mode resonance (LMR) with the electrostatic probe. ITO is an optically transparent and electrically conductive material and if its...
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Effect of wet Hydrogen Sulfide on Carbon Steels Degradation in Refinery Based on Case Study
PublicationMaterial degradation caused by wet hydrogen sulfide (Wet H2S) is one of the major issues in refineries. Carbon steel is the main construction material used in refineries and is subjected not only to thickness loss but the hydrogen is the major concern. H2S leads to high atomic hydrogen penetration in steel which causes degradation in the form of blistering and/or cracking (HIC/SOHIC) and stress cracking in the area of welds and...
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Dissimilar autogenous TIG joint of Alloy 617 and AISI 304H steel for AUSC application
PublicationTo reduce costs and improve high-temperature performance in Advanced Ultra Super Critical (AUSC) boilers, it is necessary to weld austenitic steel to Inconel alloy. In this study, the autogenous tungsten inert gas (TIG) welding process was used to join Alloy 617 and an austenitic AISI 304H steel plate of thickness 5 mm. Microstructural analysis showed that the microstructure formation was uneven along the weldments, with columnar...
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Non-enzymatic flexible glucose sensing platform based on nanostructured TiO2–Au composite
PublicationAll over the world the number of people suffering from diabetes and related complications is drastically growing. Therefore, the need for accurate, reliable and stable sensor for monitoring of glucose in human body fluids is becoming highly desirable. In this work we show that material composed of gold layers deposited onto TiO2 nanotubes (NTs) formed onto the flexible Ti foil exhibits great response toward glucose oxidation and...
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The possibility of estimating the height of the ionospheric inhomogeneities based on TEC variations maps obtained from dense GPS network
PublicationA state of the ionosphere can be effectively studied using electromagnetic signals received from global navigation satellite systems (GNSS). Utilization of the dual frequency observations allows estimating values of the total electron content (TEC). They can be used for a number of scientific studies such as detection and monitoring of traveling ionospheric disturbances or plasma bubbles. Moreover, maps of TEC variations allow...
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The fracture behaviour of notched PMMA specimens under simple loading conditions – Tension and torsion experimental tests
PublicationThis paper presents the results of experimental testing of flat PMMA specimens during uniaxial loading conditions. Two separate tests were conducted: tensile and torsion. The specimens were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. The specimens were made in two thickness variants: 5 and 15 mm. Monotonic tensile and torsion tests were carried out while keeping the averaged strain rate constant,...
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A novel one-variable first-order shear deformation theory for biaxial buckling of a size-dependent plate based on Eringen’s nonlocal differential law
PublicationPurpose – This paper aims to present a new one-variable first-order shear deformation theory (OVFSDT) using nonlocal elasticity concepts for buckling of graphene sheets. Design/methodology/approach – The FSDT had errors in its assumptions owing to the assumption of constant shear stress distribution along the thickness of the plate, even though by using the shear correction factor (SCF), it has been slightly corrected, the errors...
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Modelling hydraulic and capillary-driven two-phase fluid flow in unsaturated concretes at the meso-scale with a unique coupled DEM-CFD technique
PublicationThe goal of the research was to demonstrate the impact of thin porous interfacial transition zones (ITZs) between aggregates and cement matrix on fluid flow in unsaturated concrete caused by hydraulic/capillary pressure. To demonstrate this impact, a novel coupled approach to simulate the two-phase (water and moist air) flow of hydraulically and capillary-driven fluid in unsaturated concrete was developed. By merging the discrete...
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Structural and dynamic properties of water within the solvation layer around various conformations of the glycine-based polypeptide
PublicationSeveral conformations of the solvated glycine-based polypeptides were investigated using molecular dynamics simulations. Some properties of water in the neighbouring space around these molecules were investigated. It was found, that water forms a well-defined layer - the first solvation shell - around the peptide molecule, and thickness of this layer is independent of the peptide structure, and it equals to approximately 0.28 nm....
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Time-frequency analysis in optical coherence tomography for technical objects examination
PublicationOptical coherence tomography (OCT) is one of the most advanced optical measurement techniques for complex structure visualization. The advantages of OCT have been used for surface and subsurface defect detection in composite materials, polymers, ceramics, non-metallic protective coatings, and many more. Our research activity has been focused on timefrequency spectroscopic analysis in OCT. It is based on time resolved spectral analysis...
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Application of adjusted subpixel method (ASM) in HRCT measurements of the bronchi in bronchial asthma patients and healthy individuals
PublicationBackground: Recently, we described a model system which included corrections of high-resolution computedtomography (HRCT) bronchial measurements based on the adjusted subpixel method (ASM).Objective: To verify the clinical application of ASM by comparing bronchial measurements obtained bymeans of the traditional eye-driven method, subpixel method alone and ASM in a group comprised ofbronchial asthma patients and healthy individuals.Methods:...
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The miniaturised emission chamber system and home-made passive flux sampler studies of monoaromatic hydrocarbons emissions from selected commercially-available floor coverings
PublicationThe estimation of the emission rate of organic compounds released from various types of indoor materials can be performed using stationary environmental test chambers (ETC) classified as ex-situ methods or small-scale portable analytical devices based on the use of passive technique at the stage of analytes sampling from the gaseous phase (in-situ methods). The paper presents results of emissions of selected organic compounds from...
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Tailoring the optical parameters of optical fiber interferometer with dedicated boron-doped nanocrystalline diamond thin film
PublicationOptical fiber interferometer using nanocrystalline boron-doped diamond film was investigated. The diamond films were deposited on glass plates using a Microwave Plasma-Enhanced Chemical Vapour Deposition (μPE CVD) sys-tem. The growth time was 3h, with boron doping level of 10 000 ppm producing films (B-NCD-10) of thickness ~ 200 nm. The presence of boron atoms in the diamond film is evident in Raman spectrum as peaks at 1212 cm-1...
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Wear of electroplated diamond tools in lap-grinding of Al2O3 ceramic materials
PublicationCurrent development of modern products, together with ever-increasing demands for their operation and usage, necessitate the search for new processing methods. Abrasive machining is widely used in many industrial areas, especially for processing difficult-to-machine materials such as advanced ceramics. Grinding with lapping kinematics, also called lap-grinding, is still one of the innovative methods of abrasive processing being...
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Effect of Thermal Treatment of Birch Wood by Saturated Water Vapor on Granulometric Composition of Chips from Sawing and Milling Processes from the Point of View of Its Processing to Composites
PublicationThe goal of this work is to investigate the impact of thermal modification of birch wood with saturated steam on the particle size distribution of the sawing and milling process. Birch wood (Betula pendula Roth) is an excellent source to produce plywood boards. Wastes from mechanical processing of birch wood are suitable to produce composite materials. Granulometric analyses of chips from sawing processes on the PRW 15M frame saw,...
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Diatomaceous earth as a drug-loaded carrier in a glass-ionomer cement
PublicationThe effect of a natural filler (diatomaceous earth [DE], a promising drug-delivery agent) and its content was investigated on the performance of a model glass-ionomer cement (GIC). Three sample series, differing in DE content (0, 2.5 and 5 wt%), were prepared using a commercial GIC as a matrix (3M Ketac Molar Easymix). The resultant surface microhardness and roughness, wear performance, and compressive strength of the samples were...
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An analytical four-layer horizontal electric current dipole model for analysing underwater electric potential in shallow seawater
PublicationThe paper presents a new analytical four‑layer (air–water–bottom–non‑conductive layer) horizontal electric dipole model which allows an accurate approximation of ship’s Underwater Electric Potential (UEP) from a sufficient depth in shallow coastal marine waters. The numerical methods, usually Finite Element Method (FEM) or Boundary Elements Method (BEM), are typically used to estimate the electric field and the distribution of...
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Architectural and Urban Planning Solutions for the Protection of Heritage Buildings in the Context of Terrorist Attacks: Following the Example of Passive Protection Systems
PublicationEvents in recent years showing numerous terrorist attacks raise awareness regarding the neces-sity of considering the safety of heritage buildings. The analysis of available data allows us to conclude that it is not possible to fully prevent terrorist attacks. On the other hand, it is possible to minimize the impact of such incidents through proper design of Passive Protection System (PPS) components. One possible architectural...
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Thermal dewetting as a method of surface modification of the gold thin films for surface plasmon resonance based sensor applications
PublicationHere, we report a quick and simple approach with low, optimized production costs to obtain surface plasmon resonance (SPR) based sensors fabricated through a time- and resource-effective method based on thermal dewetting of thin Au films. From the applicative point of view, the method of detection presented here should be easier to implement, since light transmission measurements seem to be much less challenging than light refractive...
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Physicochemical and Mechanical Performance of Freestanding Boron-Doped Diamond Nanosheets Coated with C:H:N:O Plasma Polymer
PublicationThe physicochemical and mechanical properties of thin and freestanding heavy boron-doped diamond (BDD) nanosheets coated with a thin C:H:N:O plasma polymer were studied. First, diamond nanosheets were grown and doped with boron on a Ta substrate using the microwave plasma-enhanced chemical vapor deposition technique (MPECVD). Next, the BDD/Ta samples were covered with nylon 6.6 to improve their stability in harsh environments and...
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Experimental Study on the Effectiveness of Polyurethane Flexible Adhesive in Reduction of Structural Vibrations
PublicationThe aim of the present study is to consider the idea of using polyurethane flexible adhesive in to reduce the vibrations in structures exposed to dynamic loads and evaluate their damping properties in relation to large deformations. Firstly, two aluminium cantilever beams, simulating structural elements (without and with polyurethane layer in the form of tape), were analysed, in order to check the damping of the unconstrained polymer...
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Analysis of pavement structure sensitivity to passage of oversized heavy duty vehicle in terms of bearing capacity
PublicationOversized heavy duty vehicles occur in traffic very rarely but they reach extremely high weights, even up to 800 tonne. The detrimental impact of these vehicles on pavement structure is much higher than in case of commercial vehicles that comprise typical traffic, thus it is necessary to assess the sensitivity of pavement structure to passage of oversized vehicles. The paper presents results of sample calculations of load equivalency factor...
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Wire Arc Additive Manufactured Mild Steel and Austenitic Stainless Steel Components: Microstructure, Mechanical Properties and Residual Stresses
PublicationWire arc additive manufacturing (WAAM) is an additive manufacturing process based on the arc welding process in which wire is melted by an electric arc and deposited layer by layer. Due to the cost and rate benefits over powder-based additive manufacturing technologies and other alternative heat sources such as laser and electron beams, the process is currently receiving much attention in the industrial production sector. The gas...
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Study on extraction and characterization of anchote (Coccinia abyssinica) starch and reinforced enset (Ensete ventricosum) fiber for the production of reinforced bioplastic film
PublicationPopulation expansion is causing an increase in dependence on plastic materials. The worst aspects of conventional plastics were their inability to biodegrade, their poor capacity to transmit water vapor, and their production of greenhouse gases. Usages of bioplastics are necessary for the advancement of a green economy and environment in order to eradicate these drawbacks of traditional plastics. In this study, reinforced bioplastic...