18 research outputs found

    Chemical, Magnetic and X-Ray Diffraction Studies of the Sediments from Oil Field in Argentina

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    Chemical, magnetic, and phase composition analysis of deposits taken from sedimentation tank from oil plant in Argentina was carried out. Energy dispersive spectroscopy indicates iron as a main sediment component with the site dependent fraction ranging from 11% to 78% (weight percentage). Moreover, large fractions of sulfur (4%-33%), oxygen (8%-28%), calcium (1%-14%), and silicon (1%-11%) were found. The chemical analysis performed with wet chemical methods also indicated Fe as a main component (about 35%), additionally a large fraction ( ≈ 15%) of the sulfur and under 10% fractions of calcium ( ≈ 7%), carbon ( ≈ 6%), and silicon ( ≈ 5%) were found in the sample. The phase composition studies performed using X-ray diffraction showed magnetite - Fe3O4Fe_3O_4, goethite - α-FeOOH, lepidocrocite - γ-FeOOH, siderite - FeCO3FeCO_3, and iron-sulfur compounds (mackinawite - FeS, stoichiometric FeS, greigite - Fe3S4Fe_3S_4) and other compounds like aragonite - CaCO3CaCO_3, calcite - CaCO3CaCO_3, anorthite - CaAl2Si2O8CaAl_2Si_2O_8, quartz - SiO2SiO_2 and barium sulphate Ba(SO3)0.3(SO4)0.7Ba(SO_3)_{0.3}(SO_4)_{0.7}. Studies performed by the Mössbauer spectroscopy, confirmed presence of majority of compounds identified by X-ray diffraction. Magnetic AC susceptibility measurements show that magnetite is a main component of the studied deposit. High concentration of the magnetic compounds deposited in the sedimentation tank points to the advisability to install the magnetic device designed to support water treatment processes, i.e.: flocculation, coagulation, sedimentation, and filtration. This device could simultaneously inhibit microbiological and chemical corrosion

    Growth and Characterisation of Pulsed-Laser Deposited Tin Thin Films on Cube-Textured Copper at Different Temperatures

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    High-quality titanium nitride thin films have been grown on a cube-textured copper surface via pulsed laser deposition. The growth of TiN thin films has been very sensitive to pre-treatment procedure and substrate temperature. It is difficult to grow heteroexpitaxial TiN films directly on copper tape due to large differences in lattice constants, thermal expansion coefficients of the two materials as well as polycrystalline structure of substrate. The X-Ray diffraction measurement revealed presence of high peaks belonged to TiN(200) and TiN(111) thin films, depending on used etcher of copper surface. The electron diffraction patterns of TiN(200)/Cu films confirmed the single-crystal nature of the films with cube-on-cube epitaxy. The high-resolution microscopy on our films revealed sharp interfaces between copper and titanium nitride with no presence of interfacial reaction

    Numeryczna i doświadczalna analiza pękania atrombogennych powłok nanoszonych na komory wspomagania pracy serca w próbie mikrościnania

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    The Polish left ventricular assist device (LVAD – RELIGA_EXT) will be made of thermoplastic polycarbonate-urethane (Bionate II) with deposited athrombogenic nano-coatings: gold (Au) and titanium nitride (TiN). Referring to the physical model, the two-scale model of LVAD developed in the previous works in the authors’ finite element code is composed of a macro-model of blood chamber and a micro-model of wall: TiN, Au and Bionate II. The numerical analysis of stress and strain states confirmed the possibility of fracture based on localization of zones of the biggest values of triaxiality factor. The introduction of Au interlayer between TiN and polymer improved the toughness of the connection, and increased the compressive residual stress in the coating what resulted in reduction of stress and strain close to the boundary between substrate and coating. However, the proper design of multilayer wall of the medical device requires the introduction of the real stress and strain states in the deposited coatings. The characteristics of TiN nano-coating such as residual stress, material model and fracture model were determined in the previously completed studies such as experimental and numercial nanoindentation tests, profilometry studies and in situ SEM’s micro-tension tests. The experimental in situ SEM’s micro-shear test was performed in the present paper and the corresponding numerical model of the test was also developed, and then, interpreted. The critical strains taken from experiment and considered as the effective strains in the model of test are the values which are the function of triaxiality factors for the tested samples. The developed in the authors’ FE code model of multilayer wall of VAD enriched with critical strain determined in the present paper enables prediction of fracture.Polska lewa komora wspomagania pracy serca (LVAD – RELIGA_EXT) zostanie wykonana z termoplastycznego poliwęglano-uretanu (Bionate II) z naniesionymi atrombogennymi powłokami: złota (Au) i azotku tytanu (TiN). W odniesieniu do modelu fizycznego, dwuskalowy model komory LVAD opracowany we wcześniejszych pracach w autorskim kodzie elementów skończonch jest złożony z modelu makro czaszy krwistej i z mikro-modelu ściany: TiN, Au i Bionate II. Analiza numeryczna stanów naprężenia i odkształcenia potwierdziła prawdopodobieństwo pękania poprzez zlokalizowanie stref o największej wartości współczynnika naprężenia trójosiowego. Wprowadzenie międzywarstwy złota pomiędzy TiN i polimer poprawiło wytrzymałość tego połączenia i powiększyło ściskające naprężenie własne w powłoce, co doprowadziło do redukcji naprężenia i odkształcenia blisko granicy pomiędzy podłożem i powłoką. Jednakże, właściwy projekt wielowarstwowej ściany urządzenia medycznego wymaga wprowadzenia rzeczywistych stanów naprężeń i odkształceń w naniesionych powłokach. Charakterystyki powłok TiN takie jak naprężenie własne, model materiału i model pękania zostały określone we wcześniej wykonanych badaniach takich jak doświadczalne i numeryczne testy nanoindentacji, badania profilometryczne, i testy mikrorozciągania prowadzone pod elektronowym mikroskopem skaningowym. W niniejszej pracy przeprowadzono doświadczalny test mikrościnania pod skaningowym mikroskopem elektronowym, opracowano model numeryczny tego testu, a następnie go zinterpretowano. Odkształcenia krytyczne otrzymane z doświadczenia i określone w modelu testu jako intensywność odkształcenia są wartościami będącymi funkcją współczynników naprężeń trójosiowych dla badanych próbek. Opracowany w kodzie własnym model elementów skończonych wielowarstwowej ściany komory VAD wzbogacony o określone w niniejszej pracy odkształcenia krytyczne umożliwia przewidywanie pękania

    Growth and Characterisation of Pulsed-Laser Deposited Tin Thin Films on Cube-Textured Copper at Different Temperatures

    No full text
    High-quality titanium nitride thin films have been grown on a cube-textured copper surface via pulsed laser deposition. The growth of TiN thin films has been very sensitive to pre-treatment procedure and substrate temperature. It is difficult to grow heteroexpitaxial TiN films directly on copper tape due to large differences in lattice constants, thermal expansion coefficients of the two materials as well as polycrystalline structure of substrate. The X-Ray diffraction measurement revealed presence of high peaks belonged to TiN(200) and TiN(111) thin films, depending on used etcher of copper surface. The electron diffraction patterns of TiN(200)/Cu films confirmed the single-crystal nature of the films with cube-on-cube epitaxy. The high-resolution microscopy on our films revealed sharp interfaces between copper and titanium nitride with no presence of interfacial reaction

    Nanostructured Thin Films β-Al-Mg Obtained Using PLD Technique

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    In this work, the pulsed laser deposition (PLD) technique was used to grow AlMg thin films from a β−Mg2Al3β-Mg_{2}Al_{3} target with nominal composition: 39.09 at.% Mg and 60.91 at.% Al. The paper presents the study of β−Mg2Al3β-Mg_{2}Al_{3} thin films deposited using the pulsed laser deposition technique. AlMg thin films were prepared on Si (400) substrates and deposited by means of using a QS-Nd:YAG laser (λ = 266, 355 nm). Samples were prepared with laser fluence (1.1 J/cm2cm^{2} and 1.6 J/cm2cm^{2}) and at two different substrate (Si) temperatures (25°C and 200°C). The target possessed columnar structure and changes in chemical composition took place as a result of the influence of the laser irradiation. Investigations focused on structure and chemical composition showed that the films generally had nanocrystalline structure and that the quantity of Al and Mg varied in the films

    Nanostructured Thin Films β-Al-Mg Obtained Using PLD Technique

    No full text
    In this work, the pulsed laser deposition (PLD) technique was used to grow AlMg thin films from a β−Mg2Al3β-Mg_{2}Al_{3} target with nominal composition: 39.09 at.% Mg and 60.91 at.% Al. The paper presents the study of β−Mg2Al3β-Mg_{2}Al_{3} thin films deposited using the pulsed laser deposition technique. AlMg thin films were prepared on Si (400) substrates and deposited by means of using a QS-Nd:YAG laser (λ = 266, 355 nm). Samples were prepared with laser fluence (1.1 J/cm2cm^{2} and 1.6 J/cm2cm^{2}) and at two different substrate (Si) temperatures (25°C and 200°C). The target possessed columnar structure and changes in chemical composition took place as a result of the influence of the laser irradiation. Investigations focused on structure and chemical composition showed that the films generally had nanocrystalline structure and that the quantity of Al and Mg varied in the films

    Composite coatings of polylactide with graphene oxide and hydroxyapatite on titanium

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    Investigation of Sediments Causing Damage to Water Meters in a Large Drinking Water Distribution System

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    Preliminary studies on the sediments collected from water meters of Krakow water supply system were performed in the cooperation with the Municipal Water Supply and Sewage. Creation and deposition of sediments on the measuring devices installed in the water supply system is a serious technological and economical problem for water companies, defectively operating for this reason water meters must be replaced. It is evident that knowledge of the chemical and phase composition of sediments is an important step towards resolving the problem of impurities in water supply systems. Four different samples of sediments, coming from water meters, were investigated using the proton-induced X-ray emission, the X-ray diffraction, the Fourier transform infrared and Raman spectroscopy. The X-ray methods revealed presence of amorphous and fine-crystalline phases as well as high content of iron-based compounds. As a crystalline phase, the most frequently appeared: goethite, lepidocrocite, iron oxides (hematite, maghemite, magnetite), calcium carbonate, and quartz. In one of the samples, the nanocrystalline phase was found and identified as hydrous iron oxyhydroxide ferrihydrite. Vibrational spectroscopy methods confirmed the composition of crystalline phases as well as enabled to estimate the abundance of amorphous phase in samples

    Digital image correlation of coated and uncoated Religa Heart_Ext ventricular assist device

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    The digital image correlation is used to estimate influence of deposited heamocompatible coatings (gold and titanium nitride) on mechanical response of ventricular assist device Religa Heart_Ext made of Bionate II (thermoplastic polycarbonate urethane) under working conditions by comparison of the coated Religa Heart_Ext with uncoated Religa Heart_Ext. The DIC is applied for experimental investigation of the strains and displacements distribution on external surface of the blood chamber of ventricular assist device during loading. The experiment was conducted in a hydraulic system with water at operating temperatures of 25 and 37 °C, as well as under static pressures: 80, 120, 180, 220 and 280 mmHg, and static underpressures: –25, –45, –75 mmHg. The subsequent images were taken after stabilization of pressure on a set level. The applied research method shows that the nano-coating of 30 nm in thickness significantly affects deformation of the blood chamber of Religa Heart_Ext in macro scale. The proposed composition of coatings increases strain on external surface of the ventricular assist device
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