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EN
The work focused on developing functional coatings on titanium substrates that would facilitate the integration with the cardiac tissue and with a specific form of connective tissue like blood. Surface modifications consisted in the laser evaporation of part of the biocompatible layer, thus creating a suitable environment for a particular tissue. For the myocardium integration, the metal surface was refined by biohemocompatible coatings. Such surfaces were the starting point for further modifications in the form of channels. The channeled surfaces enabled a controlled cell migration and proliferation. The interaction of endothelial cells with the material was highly dependent on the surface characteristics such as: topography, microstructure or mechanical properties. The controlled cellular response was achieved by modifying the surface to obtain a network of wells or channels of different dimensions via the laser interference lithography. This technique determined a high resolution shape, size and distribution patterns. As a result, it was possible to control cells in the scale corresponding to biological processes. The surface periodization ensured the optimal flow of oxygen and nutrients within the biomaterial, which was of a key importance for the cell adhesion and proliferation. The work attempted at producing the surface networks mimicking natural blood vessels. To stimulate the formation of new blood vessel the finishing resorbable synthetic coatings were applied on the surface to act as a drug carrier. Therefore, the initial trial to introduce factors stimulating the blood vessels growth was performed.
EN
The acquisition parameters and methodology of seismic data processing for high-resolution seismic imaging viewed through relative amplitude preservation are presented. An example of the obtaining of high-quality, shallow seismic data with a variable end-on spread is shown. The source used for the project is an accelerated weight drop. The study area lies within the mine waste disposal area, near Rudna village (Fore-Sudetic Monocline, WS Poland), and results are given for a 2D experimental profile. The aim of the project was to design optimal acquisition and processing parameters for the detailed recognition of Tertiary deposits. The proposed acquisition parameters are a compromise between time, cost and results. High-resolution seismic imaging enables the determining of layers within the range of thicknesses between 5 and 15 m, while the maximal depth of imaging reaches 400 m.
EN
The method of moments enables effective magnetostatic modelling of thin layers, where thickness of the layer should be considered. This paper presents the non-linear extension for this method of modelling. An initial magnetization curve, necessary for modelling, was reconstructed from saturation hysteresis loops on the basis of the Jiles–Atherton model. Finally, the set of non-linear equations was stated, and an example of solution for a square-shaped magnetic thin layer is presented.
EN
The surface passivation with titanium sol-gel coatings is a frequently used technique to control the adsorption of selected biological macromolecules and to reduce the exposure of the bulk material to biological matter. Due to the increasing number of new coating-preparation methods and new gel compositions with various types of additives, the quality and homogeneity determination of the surface covering is a critical factor affecting performance of any implanted material. While coating thickness is easy to determine, the homogeneity of the surface distribution of coating materials requires more elaborate methodologies. In the paper, the laser induced breakdown spectroscopy (LIBS) based method, capable to quantitate the homogeneity and uniformity of the europium in titanium dioxide sol-gel coatings on stainless steel surfaces prepared with two different procedures: spin-coating and dip-coating, is presented. The emission intensity of titanium has been used to determine the coating thickness whereas the relative values of europium and titanium emission intensities provide data on the coating homogeneity. The obtained results show that the spin-coating technique provides better surface coverage with titanium dioxide. However, when the surface coating compositions were compared the dip-coating technique was more reliable.
PL
W artykule przedstawiono wyniki badań właściwości elektrycznych warstw cienkich naniesionych na powierzchnię teflonu za pomocą technologii nanoszenia próżniowego. Dzięki poprawieniu właściwości adhezyjnych podłoża teflonowego poprzez modyfikację wiązką światłowodowego lasera impulsowego nanosekundowego uzyskano zmniejszenie rezystancji osadzanych ścieżek przewodzących.
EN
The paper presents results of examination of the electrical properties of conductive layers made in PVD process on the Polytetrafluoroethylene (PTFE, Teflon). Due to improvement of adhesive properties of PTFE substrate by laser modification with nanosecond pulses of fiber laser the decrease of resistance of deposited conductive paths was achieved.
EN
Carbon nanotubes are nanometric-sized materiale which possess a set of interesting features that favor their applications in various fields of materials engineering, including biomedical applications. However, their usage as implants or in nanomedicine raises many questions, regarding their potential cytotoxicity, relative to their length, diameter, structure and functional groups, present on their outer walls. The given study presents a physiochemical and biological in vitro (in accordance with EN-ISO 10993-5) evaluation of thin carbon nanotubes films, deposited on the surface of titanium, by means of the EPD process. Experiments were carried out on commercially available, pre-functionalized with OH groups, multi-walled carbon nanotubes. The obtained material is proven to be biocompatible, with no cytotoxic effect on the human fetal osteoblast cell line. During the study, selectivity of the EPD process was proven - performed experiments revealed that the process favors deposition of CNTs with chosen set of features from the stock solution. Presented results point out that the EPD process can be successfully applied as a method for fractioning the CNTs, aimed to fabricate non-toxic layers that might be considered for various biomedical applications.
PL
W pracy prezentowane są techniki pomiarów profili optycznych cienkich warstw wyznaczone z profilometrii optycznej i elipsometrii skaningowej. Pierwsza z wymienionych metod umożliwia uzyskanie mapy lokalnych współczynników odbicia z małych obszarów powierzchni (10-2 mm2), druga metoda umożliwia wyznaczanie zmiany stanu polaryzacji wąskiej wiązki promieniowania odbitego od cienkich warstw. Badania te pozwalają opisać topografię powierzchni z dużych obszarów (rzędu od kilku do kilkunastu cm2) uzupełniając tym samym pomiary wykonane przy pomocy mikroskopii sił atomowych (AFM). Analiza obrazów uzyskana przy użyciu tych metod, umożliwia wyznaczenie parametrów topograficznych powierzchni i warstw.
EN
The work presents thin film profiles measured by the optical profilometry PO and spectroscopic ellipsometry SSE techniques. First technique allows to get the surface map of intensities collected from small (10-2 mm2) spots while the second allows to obtain surface map of the phase differences of reflected radiation from studied sample. These studies enable to find many interesting features concerning surfaces in a much larger area than AFM technique. The analysis of obtained images allowed to determine most important statistic parameters of film surfaces, as variation of film thickness, surface roughness, and distribution of height irregularities.
PL
W artykule przedstawiono możliwości eksploatacji pokładów cienkich w kopalniach wchodzących w skład Katowickiego Holdingu Węglowego. Przeanalizowano ilość węgla, którą z pokładów cienkich można wyeksploatować, oraz jego podstawowe parametry, tj. wartość opałową, zawartość popiołu i zawartość siarki. Ponadto przedstawiono charakterystykę techniczną kombajnowego kompleksu ścianowego dla ścian niskich firmy Famur, który jest stosowany przy eksploatacji pokładów cienkich w KWK „Murcki-Staszic” Ruch „Staszic”.
EN
Polymer fibres have the great potential for application due to their large surface area relative to volume, incomparably large length relative to the cross-section, high strength and ease of forming the nonwovens in thermal processing. Due to the specific properties of textiles, they are applied, among others in the manufacture of filters, sensors, biomedical devices and protective clothing. This study was aimed to evaluate the surface morphology of polypropylene nonwoven modified with metallic layers CuSn, CuZnNi, NiCuFe, deposited by the magnetron sputtering technique. There was also carried out a qualitative and quantitative analysis of deposited thin layers and their compositions were compared with compositions of targets used for magnetrons. The surface morphology was tested using the metallographic optical microscope with a CF160 optical system and the scanning electron microscope adapted to work in an environmental mode. A study of composition was based on a microanalysis using the energy dispersive X-ray radiation deriving from the excited atoms (EDS).
10
Content available remote Zmodyfikowana Metoda Elementów Brzegowych dla cienkich warstw
PL
Niniejsza praca ma na celu przedstawienie rozwiązanie problemu cienkich warstw metodą elementów brzegowych. Cienkie warstwy znajdują zastosowanie w wielu inżynierskich aplikacjach takich jak proces tomografii. W klasycznym podejściu metoda elementów brzegowych nie jest idealnym narzędziem do analizy cienkich warstw, w tym celu proponujemy nowe podejście do rozwiązania tego problemu.
EN
Solution of the thin layers problem using boundary element method is presented in this paper. It is well known that the thin layers can be found in many engineering applications for example in process tomography. The classical approach to the boundary element method is not generally an ideal numerical tool for analysis of thin layer, that is why we propose the novel approach to this problem.
PL
Celem pracy jest charakterystyka cienkich warstw naniesionych na powierzchnię narzędzi wykonanych ze stali szybkotnącej metodami: RF PACVD oraz RF PACVD/MS. Warstwa azotowana wytworzona została za pomocą technologii RF PACVD z plazmy wyładowania częstotliwości radiowej, natomiast proces RF PACVD/MS zakłada syntezę warstwy diamentopodobnej w procesie rozpylania magnetronowego oraz dysocjacji węglowodorów w polu wysokiej częstotliwości. Morfologia powierzchni oraz grubość wytworzonych warstw została scharakteryzowana za pomocą skaningowej mikroskopii elektronowej (SEM) oraz mikroskopii świetlnej. Adhezję warstwy węglowej do stalowych podłoży określono za pomocą metody rysy. Przeprowadzone zostały pomiary twardości oraz właściwości tribologicznych. Współczynnik tarcia oraz odporność na ścieranie wyznaczone zostały metodą kulka-krążek z zastosowaniem kulki ceramicznej ZrO2, natomiast twardość zbadano techniką nanoindentacji. Uzyskane wyniki badań laboratoryjnych potwierdzają wysoki potencjał aplikacyjny zastosowanych technologii w obróbce drewna oraz materiałów drewnopodobnych.
EN
The main aim of work is the characteristics of layers deposited onto surfach of high speed cutting tools using RF PACVD and RF PACVD/MS methods. RF PACVD technology was used to synthesize nitrided layers using radio frequency plasma discharge, whereas RF PACVD/MS technology assumes the deposition of a-C:H/Ti gradient layers using the magnetron sputtering of Ti cathode and dissociation of hydrocarbons in high frequency electromagnetic field. Morphology and thickness of deposited layers was investigated using scanning electron microscopy (SEM) and light microscopy. Adhesion measurements of carbon layers was performed using the scratch test method. Tribological features of both types of layers were investigated with use of the ball-on-disc method where as the counterpart material ZrO2 ceramic ball was used. Hardness measurements were made using the nanoindentation method. Obtained laboratory investigation results prove the possibility of application of both technologies in wood and wood like materials machining industry.
EN
In this paper, the electrodeposition by direct and pulse periodic currents of nano- and micro-crystalline copper films and composite thinlayers is effectively examined. In the first step, electrical and physico-chemical characterizations of the copper films are realized, and the optimized electrodeposition parameters are so considered. The attention is focused on such material characteristics as microstructure, thermal and electrical conductivities and on process realization parameters leading to major differences in final products. The obtained results show that the addition of a spike, and a decrease in forward current can improve the throwing power in plating quality. The study also found that the combination of multiple spikes, a low forward current and a high reverse current can significantly improve copper distribution in microvias plating. Decrease in the grains dimension of the polycrystalline copper and composite layers results in an increase of both the thermal conductivity and the electrical resistivity with the temperature. The purpose is to relate thermal and electrical performances to material properties such as grain-size distribution and the films thicknesses.
PL
W artykule przedstawiono wyniki intensywnych badań cienkich warstw z miedzi i kompozytów o strukturach nano- i mikrokrystalicznych, które zostały wytworzone metodą elektrochemiczną. W pierwszym etapie określone zostały elektryczne i fizyko-chemiczne charakterystyki cienkich warstw z miedzi i ustalono optymalne parametry ich wytarzania. Zasadnicza uwaga została odniesiona do takich wielkości jak wymiary mikrokrystalitów, termicznych i elektrycznych konduktywności i do parametrów realizacji procesu, które prowadzą do znacznych różnic tych wielkości w wyrobie końcowym. Uzyskane wyniki ukazują, że na jakość wytwarzanych cienkich warstw mają wpływ odpowiednie pulsy prądu zasilającego reaktor oraz mała stosunkowo gęstość prądu dodatniego a duża gęstość krótkotrwałych pulsów prądu ujemnego. Badania wykazały, że odpowiednia kombinacja dodatnich i ujemnych pulsów znacznie poprawia jednorodność rozkładu materiału w mikrownękach i mikrootworach. Zmniejszenie wymiarów ziarn polikrystalicznej miedzi i kompozytów skutkuje zwiększeniem się ich zarówno termicznej konduktywności, jak i elektrycznej rezystywności wraz ze wzrostem temperatury. Stąd też znaczenia nabiera ustalenie dokładnych relacji miedzy termicznymi elektrycznymi charakterystykami a takimi właściwościami cienkich warstw jak ich grubość i rozkład wymiarowy krystalitów oraz dynamika ich wzrostu.
PL
W pracy zbadano możliwość zastosowania siły termoelektrycznej powstającej przy dużych gradientach temperatur w cienkich warstwach tlenków metali o właściwościach półprzewodnikowych do rejestracji odpowiedzi adsorpcyjnej w czujnikach gazowych. Wykazano, że zastosowanie siły termoelektrycznej pozwala poprawić charakterystyki metrologiczne czujników gazowych.
EN
Application possibilities of thermoelectric force that forms at big temperature gradients in thin metal-oxide layers of semiconducting properties to record adsorption response in gas sensors have been investigated. It has been shown that the application of thermoelectric force makes possible to enhance measuring characteristics of gas sensors.
14
EN
The hybrid materials are characterised by the very Iow friction coefficient (less than 0.03) which gives a chance of their application. It has been demonstrated that the hybrid ceramic-organic coating can be produced by means of the sol-gel technique. The tribological properties of these coatings can be controlled by means of modifiers that functionalise the silica or organically modified silica (for instance aminosilica). These modifications can be performed both from the liquid phase and gaseous phase, which enables implementation of the numerons substances that are tribologically active.
PL
Technologie mikroelektroniczne wymagają opracowania metod pomiaru przewodnictwa cieplnego materiałów otrzymywanych w postaci cienkich warstw nanoszonych na metaliczne lub ceramiczna podłoża. Metoda 3-omega pozwala na wykonanie dokładnych pomiarów przewodnictwa cieplnego materiałów litych oraz warstw w kierunku prostopadłym do podłoża. Opisano opracowaną metodę oraz układ pomiarowy. Metoda została sprawdzona na różnego typu materiałach monokrystalicznych, polikrystalicznych oraz warstwach w zakresie przewodnictwa cieplnego 0,2...140 Wm-1K-1.
EN
Technology in microelectronics requires the development of methods of measuring thermal conductivities of materials in the form of films deposited on the substrate. The 3-omega provides accurate measurements of values of thermal conductivity of bulk materials and films in normal-to-plane direction. The paper describes developed method and experimental setup. The method was successfully verified on various polycrystalline materials, single crystals and layers over the thermal conductivity range from 0.2 to 140 Wm-1 K-1.
16
Content available remote Creating thin layers at the contact surface of two nonmixing liquids
EN
The paper presents the results of numerical simulation of processes aimed at production of nanostructures with the use of oil emulsions in water. The appropriate molecular models of water and oil, as well as the model of the substance which would sediment at the water - oil interface, are looked for. Such substance, after suitable solidification, would become the main component of the produced material. For the described simulations, the Molecular Dynamics method has been used throughout this paper.
EN
The aim of this article is to present a phenomenon of acoustic waves propagation in a single layer on a semi-infinite substrate from the classical theory of elasticity point of view, and recall the description of this phenomenon by G. W. Farnell and E. L. Adler issued in 1972. Additionally, the purpose is to provide tutorial-type, step-by-step scheme for the numerical algorithm, using matrix formalism, in order to calculate frequencies, velocities and polarizations of different acoustic modes propagating within a layer. It was shown how from these calculations elastic constants of materials can be derived from fittings into dependencies between velocities and acoustic wave-vectors. The approach presented is related to Brillouin light scattering (BLS) experiments. The BLS experiments provide information about acoustic modes frequencies, velocities and wave-vectors, thus supporting the fitting procedure by reduction number of the unknown parameters.
EN
Scanning acoustic microscopy (SAM) is an attractive tool in the non-destructive inspection of printed circuit boards, thick film, thin layers and microelectronic packages. For example it permits to detect subsurface delaminations, cracks and pores (air bubbles) for different materials: metals, plastics, ceramics or composites. The examples of different electronic components and circuits observed in SONOSCAN D-9000 ultrasonic microscope with frequencies of transducers between 10 Mhz and MHz and 230 MHz are presented in this paper.
19
Content available remote Modelling of nanoindentation to simulate thin layer behaviour
EN
The work presents a computer simulation realized with the ADINA program concerning nanoindendation test. A shape of nanoindenter was proposed to be similar to the real sur-gical tools. The theoretical model was used to predict phenomena which would appear in practice. The contribution of the TiN coating thickness to the implant rigid properties was simulated. Three types of extortion conditions could be considered, Le., short contact with surgery tool (i); long continuous contact with natural tissue (ii); long cyclic contact with natural tissue (iii). In the first part of the work, the authors focused on the first type of extortion (i). The second part of the work is dedicated to the calculations of temperature impact to layer behaviour. Two layer thicknesses are considered Le., 250 nm and 50 nm. The examined coatings find serious practical applications as a blood-contacting material in medicine. The coatings were subjected to transmission electron microscopy investigations. Columnar mechanism of film growth controlled by kinetic process is stated to operate for the considered range of layer thickness. Plasma temperature is observed to influence the substrate behaviour. Examinations of thinner layers, Le. under 100nm, revealed higher degree of smoothness and uniformity, which could be related to the operation of the surface diffusion mechanism at the early stage of deposition. The physical explana-tion of TEM images was based on the finite element calculations of the temperature distribution using the ADINA program.
20
Content available remote Lock-in phase analysis of copper phthalocyanine photoabsorption spectrum
EN
The modulated photoabsorption (PA) spectra in Q-band spectral region of copper phthalocyanine (CuPc) thin layer have been investigated using two-channel lock-in phase resolved technique. Combining measurements in-phase and out-phase we determined four different features, which are observed in PA spectra. A detailed analysis of the in-phase and out-phase multicomponent PA spectra and corresponding phase diagram enabled separation of particular components as well as determination of their phase delay angle and corresponding time constants. In the CuPc sample under study, the various components of PA spectrum show different phase shifts, which implies different mechanism giving rise to the photoinduced electric field modulation.
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