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Search results for: NON-ALLOY STEELS, CLUSTER ANALYSIS, WELDABILITY
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The Use of Information and Communication Technologies in Cluster Organizations
PublicationThe purpose of the paper is to explore how cluster organizations (COs) take advantage of Information and Communication Technologies (ICT). The paper addresses the research question: “How do cluster organizations take advantage of ICT in fulfilling their main roles?”. The research was carried out in the first half of 2016 in four purposefully selected cluster organizations. The main research strategy involved Grounded Theory; the...
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NVRAM as Main Storage of Parallel File System
PublicationModern cluster environments' main trouble used to be lack of computational power provided by CPUs and GPUs, but recently they suffer more and more from insufficient performance of input and output operations. Apart from better network infrastructure and more sophisticated processing algorithms, a lot of solutions base on emerging memory technologies. This paper presents evaluation of using non-volatile random-access memory as a...
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Relationships Between Geographical and Virtual Proximity in Cluster Organisations
PublicationThe purpose of the paper is to explore the relationships between geographical and virtual proximity in cluster organizations (COs). The authors report the findings of a qualitative study conducted in four COs in Poland. The basic technique for collecting and analyzing data was an in-depth individual interview and qualitative content analysis. The research has shown that the relationships between geographical and virtual proximity...
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Torsional buckling and post-buckling of columns made of aluminium alloy
PublicationThe paper concerns torsional buckling and the initial post-buckling of axially compressed thin-walled aluminium alloy columns with bisymmetrical cross-section. It is assumed that the column material behaviour is described by the Ramberg–Osgood constitutive equation in non-linear elastic range. The stationary total energy principle is used to derive the governing non-linear differential equation. An approximate solution of the equation...
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Dissimilar underwater wet welding of HSLA steels
PublicationThe high-strength low-alloy S460ML and S460N steels were chosen for underwater wet welding of dissimilar T-joints using covered electrodes. For improving the quality of joints, the temper bead welding (TBW) method was used. The application of TBW in pad welding conditions has been investigated earlier but the possibility of usage of this technique in welded joints was not analyzed. The main aim of the study was to check the influence...
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Quality Evaluation of Agricultural Distillates Using an Electronic Nose
PublicationThe paper presents the application of an electronic nose instrument to fast evaluation of agricultural distillates differing in quality. The investigations were carried out using a prototype of electronic nose equipped with a set of six semiconductor sensors by FIGARO Co., an electronic circuit converting signal into digital form and a set of thermostats able to provide gradient temperature characteristics to a gas mixture. A volatile fraction...
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A Solution to Image Processing with Parallel MPI I/O and Distributed NVRAM Cache
PublicationThe paper presents a new approach to parallel image processing using byte addressable, non-volatile memory (NVRAM). We show that our custom built MPI I/O implementation of selected functions that use a distributed cache that incorporates NVRAMs located in cluster nodes can be used for efficient processing of large images. We demonstrate performance benefits of such a solution compared to a traditional implementation without NVRAM...
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Technological Capability and Absorptive Capacity Dynamics through Cluster Organizations, In: Sekliuckienė J., Susnienė R. (Eds). AIB-CEE 2019. Book of abstracts (pp. 127), 6th Academy of International Business Central Eastern European (AIB-CEE) chapter annual conference: „International business in the dynamic environment: changes in digitalization, innovation and entrepreneurship”, Kaunas University of Technology, Lithuania, September 25-27 (eISBN 9786090216378)
PublicationThe purpose of the paper is to portrait how members of cluster organizations (COs) perceive the role of clusters in enabling them accumulation of technological capability significant for their innovation. The authors report the findings from the qualitative study based on analysis of four COs from the metal and the highly internationalized ICT industry that concerns the role of knowledge and other cluster benefits in technological...
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Morphology and properties of nanotubular oxide layer on the Ti13Zr13Nb alloy
PublicationThe Ti13Zr13Nb alloy in solid and porous form was oxidised. The constant voltage 20 V, oxidation time 0.5 and 1 h, and 1 M H3PO4 (orthophosphoric acid) with addition of HF (hydrofluoric acid) as a test solution were applied. SEM (Scanning Electron Microscope) examinations of surface, EDS (Energy Dispersive X-ray Spectroscopy) chemical analysis, nanohardness and nano-scratch tests, and corrosion potentiokinetic tests at various...
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A Probe into the Corrosion Behavior of a WE43B Magnesium Alloy in a Simulated Body Fluid using Dynamic Electrochemical Impedance Spectroscopy
PublicationWE43B is one of the newest Mg alloys with practical application in biomedical implant technology. This work attempts to scrutinize the corrosion characteristics of WE43B alloy in a simulated body fluid (SBF) at a typical body temperature. The dynamic-electrochemical impedance spectroscopy with the capacity to track changes on surfaces in a dynamic corrosive system is used in combination with other classical techniques namely, linear...
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High temperature corrosion resistance of porous hastelloy alloy
PublicationTo further understand the suitability of Ni-Cr-base alloy for solid oxide fuel cell (SOFC), a commercial Ni-Cr-Fe-Mo alloy, Hastelloy X was selected and evaluated for oxidation behaviour under high temperature conditions. HastelloyX was chosen due to its unusual resistance to oxidizing, reducing and neutral atmospheres. For long term stability of metal supported fuel cell, the corrosion resistance plays a vital role and must be...
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MESOSCALE FUNCTIONS OF GPS SLANT DELAY
PublicationThe paper presents a computer module for GPS slant delay determination using data from COAMPS (Coupled Ocean/Atmosphere Mesoscale Prediction System) mesoscale non-hydrostatic model of the atmosphere which is run on IA64 Feniks computer cluster in the Department of Civil Engineering and Geodesy of the Military University of Technology. The slant delay is the result of integrating the ray (eikonal) equation for the spatial function...
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Development of cooperation in localized cooperation networks: A comparative study of cluster organizations and technology parks
PublicationThe main aim of the paper is to analyze the level of development of cooperative relationships in localized cooperation networks – among enterprises associated in cluster organizations and park tenants. The author reports the findings from the quantitative study carried out in the selected cluster organizations and technology parks functioning in Poland. The basic method of data collection was a survey questionnaire. The research...
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An experimental study of high-hydrogen welding processes
PublicationThis paper presents investigation results of determination of the diffusible hydrogen content in deposited metal obtained by means of two most often used methods-the glycerin method and the mercury method. Relation has been defined between results of those methods in the area characteristic of low-hydrogen as well as high-hydrogen welding processes. Relations available in the literature do not include the diffusible hydrogen content...
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Effect of native air-formed oxidation on the corrosion behavior of AA7075 aluminum alloys
PublicationThe microstructure of aluminum alloys plays a key role in their corrosion resistance. In particular, the presence of intermetallic precipitates differing in the potential from the alloy matrix induces local corrosion. The study presents the effect of native air-formed oxidation on the corrosion behavior of AA 7075 aluminum alloy. Various microscopic and spectroscopic techniques were used to examine the changes occurring in the...
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Pre-oxidation of porous ferritic Fe22Cr alloys for lifespan extension at high-temperature
PublicationPre-oxidation of porous ferritic Fe22Cr alloys was extensively studied in this paper. Weight gain measurements and SEM analysis revealed that pre-oxidation performed at 900◦C for 40 min increased the lifespan of the alloy. A Cr evaporation study did not disclose any significant influence of the pre-oxidation process on the Cr content in the alloy. For a more detailed assessment, TEM imaging and X-ray tomography measurements of...
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An analytical hierarchy process for selection of the optimal procedure for resveratrol determination in wine samples
PublicationThe study shows the application of analytical hierarchy process (AHP) in ranking the analytical procedures, that are applied for resveratrol determination in wine samples. 19 different analytical methodologies are described by metrological, economic and environmental criteria, that are further divided into 10 subcriteria. Before AHP application, the amount of input data is decreased with cluster analysis. The first run of AHP is...
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Flexural buckling and post-buckling of columns made of aluminium alloy
PublicationThe paper concerns flexural buckling and initial post-buckling of axially compressed columns made of aluminium alloy described by the Ramberg-Osgood relationship. The non-linear differential equation of the problem is derived using the stationary total energy principle and the assumptions of classical beam theory within a finite range. The approximate analytical solution of the equation leading to the buckling loads and initial...
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Typology of low developed non-metropolitan sub-regions in the European Union
PublicationThis paper shows a typology of 319 NUTS-3 sub-regions in the European Union. The selected sub-regions are non-metropolitan sub-regions, whose gross domestic product per capita in 2011 was below 75% of the EU average. The objective of this typology was to recognize diversity in the examined sub-regions as a starting point for the selection of areas for future comparative research. The typology takes into account 24 variables related...
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Artificial Neural Network based fatigue life assessment of riveted joints in AA2024 aluminum alloy plates and optimization of riveted joints parameters
PublicationThe objective of this paper is to provide the fatigue life of riveted joints in AA2024 aluminum alloy plates and optimization of riveted joints parameters. At first, the fatigue life of the riveted joints in AA2024 aluminum alloy plates is obtained by experimental tests. Then, an artificial neural network is applied to estimate the fatigue life of riveted lap joints based on the number of lateral and longitudinal holes, punch pressure,...
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Role of buttering layer composition on microstructural heterogeneity and mechanical properties of Alloy 617 and P92 steel dissimilar welded joints for future Indian AUSC program
PublicationRestrictive operating conditions (even exceeding 700 °C) of materials in advanced ultra super critical (AUSC) power plants and the need to minimize manufacturing and maintenance costs require the production of dissimilar metal welded joints (DMW). Significant differences in the physical and chemical properties of welded materials lead to phenomena that reduce the weldability of the metals used and force the search for solutions...
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Application of Multivariate Analysis Methods in Welding Engineering
PublicationPhenomena and processes taking place during welding are usually very complex and, for this reason, should be described using multivariate methods. The article discusses the methodological basis and selected application areas as regards the solving of welding problems using statistical multivariate methods. In addition, the article presents exemplary applications of the design of experiment, multiple regression analysis, cluster...
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Ocena odporności na zużycie ścierne stopów Ti na elementy pary trącej endoprotez stawu kolanowego
PublicationNajczęściej stosowanym biomateriałem tytanowym na elementy endoprotez stawu kolanowego jest stop Ti6Al4V. Z uwagi na zawartość wanadu, zaliczanego do pierwiastków o dużej toksyczności podejmowane są działania w kierunku zastąpienia wskazanego stopu - stopami bezwanadowymi. Jednym z najbardziej obiecujących jest stop Ti13Nb13Zr zawierający w swoim składzie jedynie pierwiastki witalne, niewywołujące stanów zapalnych i odczynów...
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X-ray Photoelectron Spectroscopy of Carboxylic Acids as Corrosion Inhibitors of Aluminium Alloys
PublicationThe datasets, titled X-ray Photoelectron Spectroscopy studies of citric acid adsorption on aluminium alloy 5754 in alkaline media and X-ray Photoelectron Spectroscopy studies of various carboxylic acids adsorption on aluminium alloys in alkaline media, contain XPS studies of the corrosion inhibitory action of selected dicarboxylic acids towards commercially available aluminium alloy 5754 in alkaline media at pH=11. These datasets...
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Proximity and Innovation in Clusters: How Close, How Far?
PublicationThe concept of proximity, whilst attractive cognitively, is still a poorly explored area in management sciences. The earliest publications on proximity were published at the end of the twentieth century and the development of this concept was strongly influenced by The French School of Proximity (Kirat & Lung, 1999; Rallet & Torre, 1999; Torre & Gilly, 2000; Carrincazeaux et al., 2001; Torre & Rallet, 2005). However, the most influential...
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Determination of t8/5 cooling times for underwater local dry welding of steel
PublicationKnowledge of thermal history is the basic condition for studying the structure - properties of welded joints. The determinant of thermal history is the thermal cycle, whose in-situ measurements are still a big challenge. Water as the welding environment complicates this issue even more. The article presents a method to determine an equation for calculating t8/5 cooling times for underwater gas metal arc welding of unalloyed steels...
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Studies on Silver Ions Releasing Processes and Mechanical Properties of Surface-Modified Titanium Alloy Implants
PublicationDispersed silver nanoparticles (AgNPs) on the surface of titanium alloy (Ti6Al4V) and titanium alloy modified by titania nanotube layer (Ti6Al4V/TNT) substrates were produced by the chemical vapor deposition method (CVD) using a novel precursor of the formula [Ag5(O2CC2F5)5(H2O)3]. The structure and volatile properties of this compound were determined using single crystal X-ray diffractometry, variable temperature IR spectrophotometry...
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THE INTERNATIONAL COMPETITIVENESS OF EUROPEAN UNION COUNTRIES AND STRATEGIES FOR ITS ENHANCEMENT: A TAXONOMIC ANALYSIS
PublicationThe aim of this article is to identify clusters of countries with similar levels of competitiveness among the EU-27 countries and to identify for each of the 27 EU countries the path to growth in competitiveness. The taxonomic cluster analysis conducted confirms the hypothesis that the European Union is an area with a high differentiation in terms of levels of competitiveness. The analysis shows that the strategy to increase competitiveness...
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Knowledge management implementation in small and micro KIBS : A categorization
Publicationhe main goal of the paper is to provide a statistical categorization of small and micro knowledge-intensive business service (KIBS) companies, based on their knowledge management (KM) attitude. Since knowledge is the main production factor and output of these companies, it is essential to achieve a better understanding of how they manage this resource. A questionnaire-based survey was conducted on a sample of Polish small and micro...
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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
PublicationIn the paper the method and results are presented of the testing of tribological performance of a number of hard materials available commercially. The tests consisted in unidirectional sliding with liquid lubrication. The load and velocity regime chosen were similar to a standard four-ball lubricity test with constant velocity and load increasing over time. The regime was modified in such a way that over the initial part of the...
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Whole-genome sequencing and antimicrobial potential of bacteria isolated from Polish honey
PublicationThe aim of this study was the whole-genome analysis and assessment of the antimicrobial potential of bacterial isolates from honey harvested in one geographical location—the north of Poland. In total, 132 strains were derived from three honey samples, and the antimicrobial activity of CFAM (cell-free after-culture medium) was used as a criterion for strain selection and detailed genomic investigation. Two of the tested isolates...
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The Method of a Two-Level Text-Meaning Similarity Approximation of the Customers’ Opinions
PublicationThe method of two-level text-meaning similarity approximation, consisting in the implementation of the classification of the stages of text opinions of customers and identifying their rank quality level was developed. Proposed and proved the significance of major hypotheses, put as the basis of the developed methodology, notably about the significance of suggestions about the existence of analogies between mathematical bases of...
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Chemometrics approaches to green analytical chemistry procedure development
PublicationChemometric tools are widely used in analytical chemistry for the reduction of data dimensionality, grouping of variables and processing of analytical signals. They have also the potential to be applied in analytical procedure development with the aim of minimizing the procedure’s environmental impact. The design of experiment gives the possibility to obtain much better information on the system response than in case of “changing...
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The impact of surface slope and calculation resolution on the fractal dimension for fractures of steels after bending-torsion fatigue
PublicationThe article presents the results of the fractal dimension measurements on the fatigue fracture surfaces of 10HNAP and S355J2 steels specimens after combined bending-torsion fatigue. For smooth and ring-notched specimens, three loading conditions were analyzed: (1) bending; (2) bending-torsion; and (3) torsion fatigue. Post-failure surface topography measurements were carried out on the entire fracture surfaces using an optical...
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Failure of austenitic stainless steel tubes during steam generator operation
PublicationThe article presents the failure process of austenitic stainless steels used in power devices, such as heat exchangers, steam generators, in terms of local corrosion: pitting, stress and intergranular corrosion, paying particular attention to welded joints area. The effect of steel chemical composition, microstructure, welding process and work environment was analyzed. The second part of the article presents the results of the...
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Investigation of magnetic order in a new intermetallic compound Nd2PtGe3
PublicationIn the present study we report a successful synthesis of the new intermetallic compound Nd2PtGe3 by an arc-melting method. The powder X-ray diffraction analysis indicates that this compound crystallizes in an disordered variant of the AlB2-type structure (space group P6/mmm, no. 191) with lattice parameters a = 4.2455 Å and c = 4. 1933 Å. The compound exhibits a cluster-glass transition below Tf = 2.9 K, characterized through ac...
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Effect of water salinity on properties of multipass underwater wet manual metal arc welded joints
PublicationThe weldability of steel under the water is limited due to the influence of the environment. Water causes limited visibility, presence of the residual stresses, increasing the cooling rate, and increasing the diffusible hydrogen content in deposited metal, leading to the formation of brittle microstructures in heat-affected zone (HAZ). The paper presents the results of mechanical properties testing of S420G2+M steel welded joints...
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Real-Time Monnitoring of Vegetable Oils' Thermal Degradation Using Proton Transfer Reaction Mass Spectrometry
PublicationThe volatile aldehydes, which are generated during frying, can be harmful to human health, therefore the concentration of these compounds in frying fumes should be monitored. In addition, aldehydes are markers of oils’ quality, and so it is possible to determine shelf-life or suitability for frying of these oils. Commonly, in order to determine aldehydes concentration gas chromatography is performed, however it does not allow for...
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Chemometrics for Selection, Prediction, and Classification of Sustainable Solutions for Green Chemistry—A Review
PublicationIn this review, we present the applications of chemometric techniques for green and sustainable chemistry. The techniques, such as cluster analysis, principal component analysis, artificial neural networks, and multivariate ranking techniques, are applied for dealing with missing data, grouping or classification purposes, selection of green material, or processes. The areas of application are mainly finding sustainable solutions...
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Oxidation and hydrogen behavior in Zr-2Mn alloy
PublicationThe purpose of the present research was to determine the oxidation and hydrogenation behavior in the new Zr-2Mn alloy. The oxidation of alloy was performed at temperatures between 350°C and 900°C for 30 minutes. The hydrogen charging was made for 72 h at a current density 80 mA/cm2. The charged samples were heat treated at 400°C for 4 h to obtain a uniform hydrogen profile content across the sample. The oxidation resulted in an...
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Investigation of the electrochemical behaviour of AA1050 aluminium alloy in aqueous alkaline solutions using Dynamic Electrochemical Impedance Spectroscopy
PublicationThe paper presents the electrochemical behaviour of aluminium alloy AA1050 in aqueous alkaline media in the pH range 14–8.5. Electrochemical study was applied in order to obtain comprehensive information on the mechanism and kinetics of the process of anodic dissolution of aluminium, supplemented by monitoring of surface topography using an electron microscope. The corrosion rate of AA1050 increases with increasing concentration...
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Stability of roof trusses stiffened by corrugated sheets
PublicationThe present parametric study is devoted to the stability analysis of a set of trusses stiffened by decking of corrugated steel sheets. For different parameters of corrugated sheets the critical loading of the roof is calculated. In the parametrical analysis the threshold bracing condition of the roof is obtained. Then the geometrically non-linear analysis of trusses braced by corrugated sheets was conducted. As a results of non-linear...
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APPLICATION OF CHEMOMETRIC ANALYSIS TO THE STUDY OF SNOW AT THE SUDETY MOUNTAINS, POLAND
PublicationSnow samples were collected during winter 2011/2012 in three posts in the Western Sudety Mountains (Poland) in 3 consecutive phases of snow cover development, i.e. stabilisation (Feb 1st), growth (Mar 15th) and its ablation (Mar 27th). To maintain a fixed number of samples, each snow profile has been divided into six layers, but hydrochemical indications were made for each 10 cm section of core. The complete data set was subjected...
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Properties of Composite Oxide Layers on The Ti13Nb13Zr Alloy
PublicationThe development of composite oxide layers on the Ti13Nb13Zr alloy, their structure and properties have been demonstrated. Two subsequent methods were applied to prepare the composite layers. During the first stage gas oxidation produced a solid oxide layer, and subsequently oxide nanotubes were produced by using an electrochemical method. Scanning electron microscopy (SEM), chemical analysis, energy dispersive X-ray spectroscopy...
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A study of cavitation erosion resistance of an ion nitrided titanium alloy by means of the vibration and rotating disk methods
PublicationIn this work, a comparative analysis of the cavitation erosion resistance of the Ti– 6.7Al–2.5Mo–1.8Cr–0.5Fe–0.25Si alloy (known as brand VT3-1) before and after lowtemperature ion nitriding is carried out. Two test methods were applied, using vibrative (ASTM G-32) and rotating disk rigs, respectively. The kinetic dependences of the erosive destruction of samples of titanium alloy VT3-1 in the initial state, after ion nitriding...
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Optimization of biocorrosion resistance and mechanical properties of PM Ti–XAl–2Fe–3Cu alloys by response surface methodology
PublicationIn the current study, the biocorrosion resistance and mechanical properties of the Ti–XAl–2Fe–3Cu (wt%) (X = 6, 4, 2 wt%) alloy produced by powder compact extrusion of blended elemental powders were optimized by using the response surface methodology in order to gain the best combination of processing parameters. To run the optimization process, central composite design with three equal levels of oxygen, hydrogen and aluminum was...
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Software for calculation of noise maps implemented on the supercomputer
PublicationThis paper presents investigation results relevant to the implementation of the algorithms for the calculation of noise maps. The aim of the implementation of the algorithms on the computer cluster is explained. Selected implementation details of the software called the noise propagation model are described. The interaction of the software with the data acquisition system is presented. Noise maps obtained by exploitation of the...
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Pomiar naprężeń własnych metodą Barkhausena za pomocą sondy z wirującym polem magnetycznym
PublicationW pracy przedstawiono nowy sposób pomiaru naprężeń własnych w elementach konstrukcji z wykorzystaniem polowego efektu Barkhausena. Informację o stanie naprężeń uzyskano z analizy rozkładu kątowego natężenia efektu Barkhausena zmierzonego w sposób automatyczny poprzez sondę z wirującym polem magnetycznym. Przedstawiono zasadę działania i opis układu pomiarowego oraz przykłady wykorzystania tej metody w ocenie stanu naprężenia w...
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Study on the applicability of the measurements of magnetoelastic properties for a nondestructive evaluation of thermally inducted microstructure changes in the P91 grade steel
PublicationThe paper presents the resuIts of the investigation of the influence of duration and temperature oftempering process on the magnetoacoustic properties of P91 tempered martensite ferritic steeI. Duringtempering of martensitic steels the dislocation density. which initially is very high. systematicallydecreases what is confirmed both by analysis of the width of X-ray diffraction peaks and hardnessmeasurements. Magnetic hysteresis...
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Characterisation of Escherichia coli isolates from the blood of haematological adult patients with bacteraemia: translocation from gut to blood requires the cooperation of multiple virulence factors
PublicationThe aim of the study was to investigate whether there are unique pathotypes of Escherichia coli capable of transmission from the gastrointestinal tract to the vascular bed. The study included E. coli strains isolated from clinical materials collected from 115 patients suffering from haematologic malignancies diagnosed with bacteraemia. The genotyping techniques established that 89 E. coli isolates from the blood had the same genotype...