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1
Content available Bioactivity of cement type bone substitutes
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EN
In vitro chemical stability and bioactivity of three different cement type bone substitutes were determined by incubating cement samples in the simulated body fluid (SBF) for 7 and 28 days. Morphology of sample surfaces has been studied using scanning electron microscopy (SEM) combined with an energy dispersive X-ray spectroscopy (EDS) and by atomic force microscopy (AFM). The diffuse reflectance Fourier-transform infrared spectroscopy (DRIFTS) was applied as a supplementary method. The development of bone-like apatite layers on the surface depended on their initial phase composition. Obtained cements showed good surgical handiness, high bioactive potential and were chemically stable. They seem to be promising materials for bone substitution.
EN
Changes of surface morphology considered as alteration topography and/or roughness are the main and spectacular result of ion sputtering pf solid surface. To obtain quite clear picture of morphology modification high quality investigation methods ( techniques) have tio be applied. The four of them are presented in this short review article. The first is profilometrical technique enabling surface microroughness measurements. The second - microscopical method used to observe surface topography (SEM) or topography together with nanoroughess measurements (AFM). Very interesting and promising investigation ways discussed in the paper are harmonic analysis and fractal analysis of sputtered surface profile. Technological and biomedical implications are also shown here.
EN
Ohmic contacts to AlGaN/GaN heterostructures, which have low contact resistance and a good surface morphology, are required for the development of high temperature, high power and high frequency electronic devices. The paper presents the investigation of a Ti/Al based Ti/Al/Ni/Au ohmic contact to AlGaN/GaN heterostructures. Multilayer metallization of Ti/Al/Ni/Au was evaporated by an electron gun (titanium and nickel layers) and a resistance heater (aluminum and gold layers). The contacts were annealed by rapid thermal annealing (RTA) system in a nitrogen ambient atmosphere over the temperature range from 715 to 865 °C. The time of the annealing process was 60 seconds. The chemical analysis, formation and deterioration mechanisms of Ti/Al/Ni/Au ohmic contacts to AlGaN/GaN heterostructures were studied as a function of the annealing process conditions by a scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS).
EN
Copper sulfide (CuxS) films deposited on polypropylene substrate were obtained by chemical bath deposition (CBD) method. The influence of the deposition time on the morphology of CuxS films was studied by means of scanning electron microscopy. We have found that the average particles dimension increased from 37 to 49 nm with the increase of deposition time from 20 to 30 minutes. The study of optical properties of the copper sulfide films was carried out based on optical transmission spectra recorded in the 400 – 1000 nm wavelength range. The optical constants, such as refractive index, extinction coefficient and dielectric constant as well as electrical and optical conductivity of CuxS films were calculated. The obtained values are in accordance with the ones reported in the literature: We have shown that both, morphological and optical properties of CuxS films are strongly affected by the deposition time.
EN
Gold nanoparticle array on pretreated glass substrates was fabricated by chemical surface growth from the AuCl3, CH2O and Na2CO3 components in aqueous solutions mixture. Transmission, absorption and reflectivity spectra were measured with an UV-Vis spectrophotometer. A change in plasmon maximum absorption position depending on the growth conditions was investigated. The surface morphology was studied by atomic force microscopy. The statistical analysis of the heights, particles diameter and image cross-sections was carried out by scanning probe microscopy methods and the Au NPs size dependence on the growth time was experimentally determined. The results of this paper will contribute to the optimization of plasmonic CdS/CdTe solar cell.
6
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EN
Polyethylene terephthalate (PET) foils have been exposed to oxygen plasma and its afterglow in order to reveal compositional and structural modifications of the surface layer. Oxygen plasma was created by electrode-less RF discharge in a glass chamber so the O-atom density was close to 1022 m-3 although the density of charged particles was only about 1 × 1016 m-3. Long-living reactive particles created in plasma were leaked into the afterglow chamber using a two-stage rotary pump of pumping speed 4.4 × 10-3 m3 s-1. The density of O-atoms in the afterglow as measured with a catalytic probe was 3 × 1021 m-3, while the density of reactive oxygen molecules was estimated theoretically. The functionalization was accomplished even after a brief exposure to either plasma or afterglow since all samples were saturated with oxygen-rich functional groups as revealed by XPS. The water contact angle measurements, however, showed that only plasma treatment allowed for super-hydrophilicity, explained by rich surface morphology as detected by AFM. The differences in morphological properties between plasma and afterglow treated samples were explained by different interaction mechanisms between low and high energy particles impinging the polymer surface.
EN
In this study, a new chemically modified cellulose polymer-capped ZnO nanopowder prepared by hydrothermal method using chemically modified cellulose polymer as capping agent was successfully reported. The structural characteristics of CMC-capped ZnO nanopowder was reported by FTIR, XRD, SEM and EDX studies. XRD results revealed crystallographic properties like crystal composition, phase purity and crystallite size of the prepared CMC-capped ZnO nanopowder and average size calculated by Debye Scherrer formula as 14.66 nm. EDX studies revealed that the presence of elemental compositions of capping agent in the nanopowder samples. The optical characterization of the CMC-capped ZnO nanopowder was studied using UV absorption (λ max = 303 nm) and PL spectroscopy (λ ex = 295 nm). The average crystal diameter and grain size were calculated by effective mass approximation formula and compared with XRD findings that agreed well and verified CMC capped ZnO with particle size of 193 nm. Thus, the promising optical characteristics shown by the synthesized CMC capped ZnO nanopowders exposes its potential usage in bio-medical fields.
EN
Efficiency of dye-sensitized solar cell (DSSC) depends on several interrelated factors such as type and concentration of dye, type and thickness of photoelectrode and counter electrode. Optimized combination of these factors leads to a more efficient cell. This paper presents the effect of these parameters on cell efficiency. TiO2 nanoporous thin films of different thicknesses (5 µm to 25 µm) were fabricated on indium doped tin oxide (ITO) coated glass by doctor blading method and characterized by inverted microscope, stylus surface profiler and scanning electron microscope (SEM). Natural organic dye of different concentrations, extracted from turmeric, was prepared with ethanol solvent. Different combinations of dye concentrations and film thicknesses along with different types of carbon catalyst have been investigated by I-V characterization. The result shows that the cell made of a counter electrode catalyst material prepared by candle flame carbon combined with about 15 μm thick photoelectrode and 100 mg/mL dye in ethanol solvent, achieves the highest efficiency of 0.45 %, with open circuit voltage of 566 mV and short circuit current density of 1.02 mA/cm2.
EN
A deep eutectic solvent, ethaline (as a typical representative of new-generation room temperature ionic liquids), was used to anodically treat the surface of copper-nickel alloy (55 wt.% Cu). Anodic treatment in ethaline allows flexibly affecting the patterns of surface morphology: formation of stellated crystallites and surface smoothing (i.e. electropolishing) are observed depending on the applied electrode potential. The measured values of roughness coefficient (Ra) well correlate with the changes in surface morphology. Anodic treatment of Cu-Ni alloy in ethaline contributes to a considerable increase in the electrocatalytic activity towards the hydrogen evolution reaction in an alkaline aqueous medium, which can be used to develop new high-efficient and inexpensive electrocatalysts within the framework of the concept of carbon-free hydrogen economy.
EN
Hybrid systems of silica and polyhedral oligomeric silsesquioxanes (SiO2/POSS) were obtained by the mechanical method with the use of spherical or hydrated silicas, precipitated in the emulsion or aqueous environment. The SiO2 surface was modified with the following cage silsesquioxanes: hepta(isobutyl)2-triethoxysilylethyloctasilsesquioxane, octakis ({3-glycidoxy-propyl}dimethylsiloxy)octasilsesquioxane and octakis ({3-methacryloxypropyl} dimethylsiloxy)-octasilsesquioxane. The nanofillers obtained were subjected to thorough dispersive analysis (NIBS method) and morphological analysis (transmission electron microscopy). Their wettability in water systems was evaluated and their adsorption activity was characterised by determination of the specific surface area BET, pore diameters and volume. Thermal stability of the nanofillers was checked. The effect of surface modification on the degree of coverage was assessed on the basis of elemental analysis.
11
Content available remote Interactions of high current pulsed electron beam with phosphate laser glass
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EN
Impact of electron beam bombardment on the surface of Nd3+ doped P2O5-B2O3-Al2O3-BaO laser glass was investigated. Physical properties of the bombarded glass were measured by 3D laser roughometer, microhardness tester, UV/VIS spectrometer, EDS and contact goniometer. Low beam energy had no significant impact on glass surface morphology and other properties. High beam energy increased glass surface roughness and decreased micro-hardness, UV/VIS transmittance and wetting angle. Thermal stress generated by high energy electron beam bombardment expanded the Griffith flaws and increased glass surface roughness.
EN
This work presents a study on the surface morphology, structure and optical behavior of stable phase cadmium sulphide (CdS) nanoparticles synthesized via co-precipitation technique. Scanning electron microscopy (SEM) analysis has been employed to study a cluster formation in the aggregated nanoparticles. An image analysis approach using ImageJ has been used to measure the size of nanoparticles from the SEM micrographs. Fourier transform infrared spectroscopic (FT-IR) analysis identified absorption peaks of Cd–S stretching along with moisture content. X-ray diffraction (XRD) analysis showed that CdS nanoparticles crystallized in wurtzite structure with a preferential orientation along (0 0 2) plane. The particle size, microstrain and lattice constants have been evaluated using XRD data. The lattice parameters of these nanoparticles were found to be shorter than the bulk value which led to lattice contraction. The optical absorption study showed a blue shift in the fundamental absorption edge indicating a quantum size effect.
EN
The paper presents research results of multilayer systems composed of alternate Cu/Ni layers. The layers thickness obtained by the galvanic treatment was determined by using the transmission electron microscopy and X-ray diffraction method in the grazing incidence diffraction geometry. The surface morphology was observed using scanning electron microscope with EDS microanalysis. Observation of the surface topography of systems using the atomic force microscope was also carried out.
PL
Badano wpływ dodatków alkoholowych z grupy butanoli do roztworu KOH na morfologię różnych płaszczyzn (hkl) krzemu uzyskiwanych w procesie trawienia anizotropowego. Stwierdzono, że wprowadzenie dodatków poprawia gładkość powierzchni typu (hh1) a pogarsza morfologie płaszczyzn (h11). Ma to związek z konfiguracją wiązań na tych płaszczyznach.
EN
The effect of alcohol additives from butanol group to KOH solution on the morphologies of different Si (hkl) surfaces fabricated by anisotropic etching has been studied. It was stated that the additives improve the surface roughness of (hh1)-type surfaces whereas (h11)-type surfaces undergo worsening. The effect is connected with bond configurations on the studied surfaces.
Logistyka
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2016
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tom nr 1
242--250, CD1
PL
Badania adhezji powłok akrylowych metodą odrywową udowodniły istotny wpływ chropowatości powierzchni podłoża stalowego, zależnej od gradacji papieru ściernego, na wytrzymałość jego połączenia adhezyjnego z powłoką. Stwierdzono, że im większe były rozmiary ziarna papieru ściernego, tym wytrzymałość połączenia adhezyjnego powłoki z podłożem stalowym była większa. Gradacja papieru ściernego miała również istotny wpływ na charakter zerwania kontaktu powłoki z podłożem. Badając metodą odrywową adhezję powłoki akrylowej, nałożonej na podłoże stalowe przygotowane gruboziarnistym papierem ściernym P80 (którego nasyp tworzyły ziarna elektrokorundu o rozmiarach 180÷212 μm), zanotowano rozerwanie kohezyjne w międzywarstwie, na obszarze odpowiadającym 85% powierzchni odrywanego stempla. Rozerwanie kohezyjne w warstwie podkładowej na obszarze odpowiadającym 50% powierzchni odrywanego stempla oraz rozerwanie kohezyjne w międzywarstwie, na obszarze odpowiadającym 40% powierzchni odrywanego stempla zaobserwowano natomiast w przypadku przygotowania podłoża średnioziarnistym papierem ściernym P150 (o ziarnie 90÷106 μm). Rozerwanie kohezyjne w warstwie podkładowej, na obszarze odpowiadającym 75% powierzchni odrywanego stempla stwierdzono w przypadku przygotowania podłoża drobnoziarnistym papierem ściernym P600 (o ziarnie 25÷27 μm).
EN
Investigations of acrylic coating adhesion made using pull-off method proved essential influence of steel substrate surface roughness, which depends on grain size of abrasive paper, on its adhesive coupling with the coating. It was stated that the bigger grain size of abrasive paper the higher strength of adhesive coupling between the coating and the steel substrate. Grade of abrasive paper had also essential influence on type of contact breakage between the coating and the surface. During pull-off examination of acrylic coating adhesion to steel substrate, prepared with coarse grained abrasive paper P80 (size of alundum grains 180÷212 μm), it was stated that the cohesive breakage occurred in the interlayer on the area corresponding to 85% of pulled-off stamp surface. However, the cohesive breakage in the underlayer on the area corresponding to 50% of pulled-off stamp surface as well as the cohesive breakage in the interlayer on the area corresponding to 40% of pulled-off stamp surface were observed in the case of steel substrate, prepared with medium grained abrasive paper P150 (size of alundum grains 90÷106 μm). Moreover, the cohesive breakage in the underlayer on the area corresponding to 75% of pulled-off stamp surface was stated in the case of substrate preparing with fine grained abrasive paper P600 (size of alundum grains 25÷27 μm).
18
75%
EN
Studies were conducted on the modification of titanium white surface using selected silane coupling agents. The effect of the concentration of the organic coupling agents was examined (0.5; 1 or 3 weight parts per 100 weight parts of TYTANPOL R-003, TYTANPOL R-211 or TYTANPOL R-213 preparation of titanium white). The dispersive properties were determined by an estimation of the particle size distribution curves and of the polydispersity index. Moreover, microscopic observations were conducted permitting to evaluate the surface morphology of the modified TiO2 particles. The profiles of sedimentation in water were also determined for the titanium whites and the BET specific surface areas were determined. Selected samples of the modified and unmodified titanium whites were subjected to elemental analysis.
19
Content available remote The morphological and dispersive characterization of commercial titanium dioxides
75%
EN
The physicochemical and dispersive characterizations were conducted on the selected commercial titanium dioxides produced by, Z. Ch. POLICE, S. A. The dispersive properties were defined in detail by an analysis of particle size distribution and polydispersity index. Moreover, the microscope studies were executed to evaluate the surface morphology of the studied TiO2 forms. The profiles of titanium dioxides sedimentation in water were determined and the specific surface areas were defined by the BET method.
PL
Zużycie większości części mechanicznych rozpoczyna się na powierzchni. Świadome nadanie odpowiednich właściwości powierzchni i ukształtowanie wymaganego stanu struktury geometrycznej jest tym trudniejsze dla technologa, im dłuższy i bardziej skomplikowany jest proces technologiczny. W przemyśle lotniczym procesy technologiczne projektowane są ze szczególnym uwzględnieniem odpowiedzialności i bezpieczeństwa wyprodukowanego wyrobu. Przemysł lotniczy to na ogół produkcja jednostkowa i małoseryjna, gdzie ekonomiczne jest wstępne przygotowanie komponentu poprzez selektywne spiekanie proszku Ti-6Al-4V i jego wykończeniowa obróbka skrawaniem. Jednak mikroporowatość otrzymanego w ten sposób materiału uwidacznia się dopiero po skrawaniu. To właśnie mikroporowatość może być źródłem zużycia eksploatacyjnego prowadzącego do zniszczenia części. W artykule przedstawiono wyniki badań wpływu technologicznych parametrów procesu selektywnego spiekania stopu Ti-6Al-4V na zmiany mikroporowatości, uwidaczniające się po obróbce skrawaniem w wartościach wybranych parametrów morfologii powierzchni.
EN
Wear of most mechanical parts have the beginning on the surface. Knowingly giving the relevant properties of the surface and shape of the required state of geometric structure is more difficult for the technologist at the long and more complicated technological process. In the aerospace industry processes are designed with particular emphasis on accountability and ensuring the safety of the obligation of the manufactured product. The aviation industry is generally the short series production, where cost is the initial preparation of the component by selectively melting the powder of Ti-6Al-4V and finish machining. However, the micro porosity of the thus obtained material is visible after machining. It is the micro-porosity can be a source of wear and tear leading to the destruction of parts. The article presents the results of research on the impact of technological parameters of the process of selective sintering alloy Ti-6Al-4V changes micro porosity materialized after machining in the values of the selected parameters of surface morphology.
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