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Search results for: POLYESTERS, SOLID STATE NMR, DFT CALCULATIONS
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Cavitation wearing of the SUPERSTON alloy after laser treatment at cryogenic conditions
PublicationThe purpose of this paper is to demonstrate the method of laser remelting at cryogenic conditions of the SUPERSTON alloy and its influence on microstructure and cavitation wearing. The cavitation test was performed using the rotating disc facility in IPM PAN Gdansk. During the cavitation test, the mass loss of the material with different parameters of laser remelting was determined. Surface and cross-section microstructure of the...
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High temperature oxidation of porous alloys for solid oxide fuel cell applications
PublicationW pracy proszki PI600, 317L i 430L stali użyto do przygotowania porowatych metalowych podłoży dla tlenkowych ogniw paliwowych. Po spiekaniu w różnych temperaturach oceniana była ich porowatość i wysokotemperaturową odporność na korozję. Cykliczna analiza termograwimetryczna, dyfraktometria rentgenowska i obrazów SEM były używane do opisu właściwości tych porowatych stopów. Właściwości elektryczne badano dla wybranych próbek. Wpływ...
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Research of hydrotronic variable displacement radial piston pump with electro -pneumatic control
PublicationThe paper presents the developed new electro-pneumatic control (pneumotronic) system for hydraulic fixed-displacement radial piston pump. Hydraulic fixed-displacement radial piston pump equipped with the proposed control system changes into hydrotronic variable-displacement radial piston pump. Pump flow rate control is realized by means of programmable logic controller, electro-pneumatic valves, pneumatic cylinders and a sensor.
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Effect of the Unit Pressure on the Selection Parameters of Intermetallic Coastings NiAl and Ni3Al after Platic Working
PublicationW artykule omówiono wpływ zgniotu na wybrane parametry warstwy międzymetalicznej NiAl i Ni3Al napawanej na stali C45 podanej obróbce plastycznej poprzez prasowanie na zimno.
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Analysis of Asymmetrical Rolling Process of Multilayer Plates
PublicationW niniejszej pracy przedstawiono wyniki badań numerycznych asymetrycznego procesu walcowania blach wielowarstwowych M1E-Al99,8-AlMg5. Modelowanie numeryczne procesu walcowania blach wielowarstwowych przeprowadzono w programie Forge 2D, którego obliczenia bazują na metodzie elementów skończonych. Przedstawione w pracy wyniki umożliwiły przeprowadzenie analizy procesu walcowania blach wielowarstwowych.
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Surface Roughness Model Components Created by Stereolithography Method
PublicationW pracy przedstawiono charakterystykę powierzchni elementów wykonywanych metodą stereolitografii. Opisano modele chropowatosci stosowane do opisywania powierzcni wraz z prezentacją formuł matematycznych. W oparciu o wyniki badań eksperymentalnych przeprowadzono częściową weryfikację modeli.
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Modeling and simulation of tool cycle in manufacturing cell
PublicationThe paper addresses issues concerning modeling and analysis of tool flow within a three-machine manufacturing cell used for small batch manufacturing of a definite spectrum of prismatic parts. The approach utilizes a method for job and tool allocation to work centers with limited number of machines and capacity of tool resources, based on the analysis of formalized relations: job - tool sets required. Selected tool flow control...
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Port-Based Modelling of Distributed-Lumped Parameter Systems
PublicationThere in the paper is presented an uniform, port-based approach to modelling of both lumped and distributed parameter systems. Port-based model of the distributed system has been defined by application of bond graph methodology and distributed transfer function method (DTFM). The approach proposed combines versatility of port-based modelling and accuracy of distributed transfer function method. The concise representation of lumped-distributed...
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Modal Reduction and Analysis of Gyroscopic Systems
PublicationThe paper introduces the method of the modal reduction of systems that experience the Coriolis acceleration or gyroscopic effect component. In such cases corresponding system equations are non-self-adjoined. To solve the problem modal reduced model is built up for the system without Coriolis acceleration or gyroscopic effect terms. These phenomena are included by application of any lumping technique. Hence, the final reduced model...
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Optimum Control of Gyroscopic Systems
PublicationThe problem of optimum control of transverse rotor vibrations with gyroscopic interactions has been described and solved in the paper. An integral performance index has been defined for such system in order to minimize vibration level of a chosen rotor point. For this reason, an efficient way of finding the weight coefficients of integral performance index for multi-degrees-of-freedom system with gyroscopic interactions has been...
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Redundantly Actuated 3RRR Parallel Planar Manipulator - Numerical Analyses of its Dynamics Sensitivity on Modifications of its Platform’s Inertia Parameters
PublicationIn the paper, numerical analyses, as well as dynamics of a complex mechanism, are presented. Two objectives are crucial for the paper: inverse dynamic model is needed (dedicated to be use in the model predictive controller); an identification method is searched (some trajectory parameters are controlled, when specific trajectory is tracked under an open-loop model-based control), as selected parameters must be identified for the...
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Wear of Electroplated Tools Used for Flat Grinding of Ceramics
PublicationTwo methods for the abrasive properties evaluation, based on the image processing, are presented in the paper. Image processing analysis was developed to evaluate quickly the abrasive properties as the tool wears down. The coefficient based on the image brightness was calculated and additional analysis was based on the number of grains located on the active surface of the tool before and after machining. The active surfaces of...
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Surface Structure of Components Created by Stereolitography
PublicationStereolithography is an additive rapid prototyping method. This method is based on the principle of solidifying a liquid photopolymer (resin) by laser radiation. Models obtained with this method are characterized by a specific surface structure called “stairstep effect”. It causes that, the surface should be processed by additional finishing (postprocessing). To minimize the additional machining process, the model should be set...
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Research on Tool Temperature Dependence on Lapping Grains Size
PublicationCommonly used as a finishing operation, lapping has been used for achieving ultra-high finishes and close tolerances between mating pieces. Its carried out by applying loose abrasive grains between work and lap surfaces, and causing a relative motion between them resulting in a finish of multi-directional lay. The grains activity (sliding and rolling) in the working gap causes not only the material removal but also the temperature...
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The Influence of Workpiece Hardness on Plate Temperature during One Side Lapping
PublicationLapping leads to a surface with low roughness and high precision. Because of required parts accuracy tool flatness is the key to the successful machining. To avoid its excessive thermal expansion, plate temperature research was taken. The goal was to determine the correlation between the basic lapping conditions and wheel temperature. In work Bulsara et al. authors developed model to estimate the maximum and average temperature...
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Comparison of Single and Multi-Population Evolutionary Algorithm for Path Planning in Navigation Situation
PublicationIn this paper a comparison of single and multi-population evolutionary algorithm is presented. Tested algorithms are used to determine close to optimal ship paths in collision avoidance situation. For this purpose a path planning problem is defined. A specific structure of the individual path and fitness function is presented. Principle of operation of single-population and multi-population evolutionary algorithm is described....
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Technological Problems in Lapping on Flat Surfaces of Ceramic Parts
PublicationThis paper will present the results of research on single-disc lapping of flat surfaces of small ceramic elements. Machining with the use of different tools such as metallic, two-metallic and abrasive-metallic will be analyzed. The basics and techniques of reinforcement of laps will be discussed. The results of the influence of parameters on the surface quality of ceramic conponents (sealing) for three treatments on lapping machines...
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SmallAngle Neutron Scattering Study of the Structure of Mixed Micellar Solutions Based on Nonionic and Two Cationic Surfactants
PublicationThe aggregation in mixed water systems based on nonionic surfactant, i.e., heptaethylene glycol monotetradecyl ether (C14E7), and cationic surfactants, i.e., cetyltrimethylammonium bromide (CTAB), and cetyltrimethylammonium chloride (CTAC) has been investigated using the smallangle neutron scattering method. The preliminary results of the study of the behavior of C14E7 aqueous solutions (for a concentration of 0.17%) when adding...
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Influence of pyrolysis atmosphere on the lithium storage properties of carbon-rich polymer derived SiOC ceramic anodes
PublicationPolymer derived carbon-rich SiOC ceramics are prepared from polysiloxane precursors through a pyrolysis process at 1000 °C using pure argon and argon/hydrogen mixture as pyrolysis atmosphere. The precursor is synthesized from a linear (Si–H)-containing polysiloxane cross-linked with divinylbenzene using hydrosilylation reaction in the presence of a platinum catalyst. Pyrolysis in Ar/H2 mixtures, compared to the treatment under...
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A simplified model of 3-D pipe system conveying flowing liquid
PublicationThe paper presents a model reduction technique of a 3-D pipe system with flowing liquid. In the analysis and design of control (mechatronic) systems it is useful to work with simple, low order models. A hybrid reduced order model is proposed. The system model consists of two parts, the modal model and the finite element model.
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Influence of Flat Lapping Kinematics on Machinability of Ceramics
PublicationNew tools for flat grinding of ceramics are presented in the paper. Electroplated CBN tools (B64 and B107) were used in a modified single-disc lapping machine configuration. The results from experiments, such as the material removal rate and surface roughness parameters are presented and analyzed. Numerical simulations, based on the model for the shape error and tool wear estimation in machining with flat lapping kinematics, are...
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The effect of pre-hydrogen charging on corrosion behaviour of superduplex stainless steel welded joints
PublicationThe paper presents results of research undertaken to determine the influence of hydrogen on passivity and corrosion resistance of 2507 super duplex stainless steel welded joints. Butt welded joints were made with low heat input using flux corded arc welding (FCAW) method. Coupons of 5.0 x 5.0 mm were cut from the welded joints containing weld metal (WM), heat affected zone (HAZ) and parent metal (PM). Hydrogen was introduced...
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Deformation of the Structural Details of the Components Created by the Rapid Prototyping Method
PublicationThe paper present the results of preliminary research and describes the deformation of construction details within the process of producing small element employing a stereography system. The article discuses a scheme for changes in data conversion. Variation in construction details have been described on the basis of analysing photographs.
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Hardened Steel Surface Waviness Created by Rolling Burnishing Process
PublicationThe surface of the finishing machined parts is defined mainly by roughness parameters. Growing demands on the part, especially mating sliding or rolling, require the specification of additional parameters, such as waviness parameters, particularly when there is significant resistance to seizing or noise reduction. This paper presents surface waviness characteristics of hardened burnished steel.
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The Roughness of the Hardened Steel Surface Created by the Rolling-Burnishing Process
PublicationBurnishing hard materials can be used as an alternative finishing process. this paper presents the results of burnishing hardened steel. The article discusses surface deformation that occurs during this process and depends on the selected parameters of the geometric structure of the force applied for surface burnishing.
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Evaluation of Wear Resistance of Ti alloys used for elements friction of knee endoprosthesis
PublicationThe paper presents research results of resistance to abrasive wear of titanium alloys: Ti6Al4V (commonly used) and Til3Nb13Zr (alloy of new generation) in association with polyethylene (UHMW-PE) predisposed for elements on pair of the knee endoprosthesis. The results were analysed from the point of possibility of an use of new generation titanium alloys as components of such implants. The tests of resistance to abrasive wear of...
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Synthesis and structural properties of (Y, Sr)(Ti, Fe, Nb)O3−δ perovskite nanoparticles fabricated by modified polymer precursor method
PublicationThe yttrium, iron and niobium doped-SrTiO3 powders have been successfully fabricated by a modified low–temperature synthesis method from a polymer complex. The usage of strontium hydroxide precursor instead of conventional strontium nitrate or strontium carbonate provides to the possibility of significant decrease of annealing temperature. It allows to prepare a material with sphere-shape grains of nanometric size (15–70 nm). The...
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Identification of Kinematic Excitation Function by the Modal Coordinates Estimation of the System's Dynamics
PublicationThe paper presents a method of the kinematic excitation courses’ identification in excitation points, based on the car road test acceleration at different measurement points. For the purpose of the laboratory fatigue life investigation of contemporary complex structures (e.g. cars bodies) and components of these structures (i.e. cars roofs), only a few first vibration modes are usually taken into account. During real life tests...
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Electronic conductivity in the SiO2–PbO–Fe2O3 glass containing magnetic nanostructures
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Electrical properties and structure of lead-borate glass containing iron ions
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Multi Parameter Sliding Test Result Evaluation for the Selection of Material Pair for Wear Resistant Components of a Hydraulic Motor Dedicated for Use with Environmentally Friendly Working Fluids
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Degradation of Gel-Coat Layer in Glass/Polyester Laminate in Seawater Environment
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Magnetic properties of charge ordered complex TCNQ salts with lattice distortions
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Rock salt ordered-type double perovskite anode materials for solid oxide fuel cells
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Correlation between crystal and transport properties in LnBa0.5Sr0.5Co1.5Fe0.5O5+δ (Ln - selected lanthanides, Y)
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Enhanced oxygen mobility by doping Yb in BaGd1-xYbxMn2O5+δ double perovskite-structured oxygen storage materials
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Evaluation of BaY1−Pr Mn2O5+δ oxides for oxygen storage technology
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Crystal structure and proton conductivity in highly oxygen-deficient Ba1−xLax(In,Zr,Sn)O3−δ perovskites
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Structure and transport properties of proton-conducting BaSn 0.5 In 0.5 O 2.75 and A-site substituted Ba 0.9 Ln 0.1 Sn 0.5 In 0.5 O 2.8 (Ln = La, Gd) oxides
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Cation-ordered perovskite-type anode and cathode materials for solid oxide fuel cells
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Possibility of determination of transport coefficients D and k from relaxation experiments for sphere-shaped powder samples
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Evaluation of W-containing Sr1−Ba Fe0.75W0.25O3– (x= 0, 0.5, 1) anode materials for solid oxide fuel cells
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Laser Surface Alloying of Aluminium Alloys with Cu/Fe Metallic Powders
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Laser Thermal Oxidation by Ytterbium-Doped Fibre Laser of the Hot and Cold-Rolled Stainless Steel Surface
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Structure and Mechanical Properties of Composite Layers Prepared by Laser Alloying of Aluminium Alloy
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Chemical instability of the cobalt oxyhydrate superconductor under ambient conditions
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Superconductivity in three-layer Na0.3CoO2·1.3H2O
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Generation of Optimal Process Plan Alternatives for Manufacturing Mechanical Components
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Application of Syntactic Pattern Recognition Approach in Design and Optimisation of Group Machining Systems
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The effect of Fe and Ru substitution on the superconductivity in MgCNi3
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