Ne (385)
Ano (16)
Použitá omezení
(3)
Počet nalezených dokumentů:
401
Publikováno od
do
In situ XPS characterization of diamond films after AR.sup.+./sup. cluster ion beam sputtering
Artemenko, Anna; Babchenko, Oleg; Kozak, Halyna; Ukraintsev, Egor; Ižák, Tibor; Romanyuk, Olexandr; Potocký, Štěpán; Kromka, Alexander
2015 - anglický
In this work, in situ XPS analysis of chemical composition of H- and O-terminated nano- and microcrystalline diamond (NCD and MCD) films before and after their sputtering by the Ar+ cluster ion beam was investigated. Scanning electron microscopy confirmed sputtering of all diamond surfaces with a rate about 0.5 nm/min. Raman spectroscopy and XPS revealed surface graphitization of diamond surface induced by sputtering. Moreover, XPS data showed the presence of about 0.7 % of Ar atoms on the investigated diamond surface after 66 min of sputtering. Also, oxygen residuals were still presented on the H-NCD surface after 66 min of sputtering. In contrast, no oxygen was found on the H-MCD surface just after 2 min of sputtering. Surface composition is discussed in respect to the diamond films growth parameters and surface structure.
Klíčová slova:
diamond; depth profiling; XPS; sputtering; Raman
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
In situ XPS characterization of diamond films after AR.sup.+./sup. cluster ion beam sputtering
In this work, in situ XPS analysis of chemical composition of H- and O-terminated nano- and microcrystalline diamond (NCD and MCD) films before and after their sputtering by the Ar+ cluster ion beam ...
Wettability enhancement of polymeric and glass micro fiber reinforcement by plasma treatment
Trejbal, J.; Šmilauer, V.; Kromka, Alexander; Potocký, Štěpán; Kopecký, L.
2015 - anglický
Plasma treatments were used to modify surface properties of polyethylene terephthalate (PET) and glass micro fibers, to improve their wettability. PET fibers, having diameter of 400 μm, and glass fibers (14 μm) were exposed to low pressure oxygen plasma. A direct horizontal optical method was used for contact angle measurements on fiber surfaces submerged into distilled water. Surface morphology changes before and after treatment were characterized by scanning electron microscopy. Finally, cement paste specimens reinforced with PET and lime-based mortars reinforced with glass fibers were made and after 28 days of mixture curing tested by four-point bending tests. After oxygen plasma treatment contact angles decreased by 60 % on PET fibers and by 25 % on glass fibers in comparison with untreated fibers. Next, SEM images revealed the significant surface damages of PET fibers and minor damages of glass fibers. Both four-point tested samples reinforced with treated fibers exhibited the maximum bending strength loss about to 10 to 20 percent compared to samples with untreated reinforcement.
Klíčová slova:
plasma treatments; cool oxygen plasma; wettability; contact angle; micro fibers
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Wettability enhancement of polymeric and glass micro fiber reinforcement by plasma treatment
Plasma treatments were used to modify surface properties of polyethylene terephthalate (PET) and glass micro fibers, to improve their wettability. PET fibers, having diameter of 400 μm, and glass ...
Fabrication methods of diamond coated Love wave SAW biosensors for bacterial detection applications
Drbohlavová, L.; Bulíř, J.; Valeš, Václav; Jákl Křečmarová, M.; Taylor, Andrew; Talbi, A.; Soltani, A.; Mortet, Vincent
2015 - anglický
Pathogen detection has a huge importance in the food industry and it can play significant role in the medical practice. This paper focus on the fabrication methods of diamond coated Love wave surface acoustic wave (LW-SAW) biosensors for bacteria detection. LW-SAW sensors have been fabricated on AT-quartz crystals. Interdigitated transducers have been patterned by RF sputtering and photolithography techniques. Amorphous silicon oxide (SiO2) guiding layer and nano-crystalline diamond layer were both deposited by plasma enhanced chemical vapor deposition at low temperature. Preliminary experimental study of diamond surface termination for sensors bio-functionalization is also reported.
Klíčová slova:
biosensors; LW-SAW
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Fabrication methods of diamond coated Love wave SAW biosensors for bacterial detection applications
Pathogen detection has a huge importance in the food industry and it can play significant role in the medical practice. This paper focus on the fabrication methods of diamond coated Love wave surface ...
Influence of incorporated nanodiamond particles on mechanical properties of composite material based on multi-layer PVA nanofiber textiles
Prošek, Zdeněk; Indrová, K.; Rácová, Z.; Ryparová, Pavla; Nežerka, V.; Topič, J.; Tesárek, Pavel; Kromka, Alexander
2015 - anglický
The present study investigates the influence of NDP on mechanical properties of multi-layer PVA nanofiber textiles. The particles of a diameter equal to 5 nm were incorporated into double- and triple-layer textiles, while the single-layer samples were prepared as the reference. The diameter of PVA nanofibers varied from 100 to 300 nm. We characterized the tensile strength, stiffness and ductility of fabricated nanofibers by using a conventional method – a tensile test. We found that the NDP-enriched nanofibers reveal antibacterial character. However, none or negligible influence of NDP additions on the tested mechanical properties was observed.
Klíčová slova:
nanofibers; PVA; nanodiamonds; electrospinning; mechanical properties; SEM
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Influence of incorporated nanodiamond particles on mechanical properties of composite material based on multi-layer PVA nanofiber textiles
The present study investigates the influence of NDP on mechanical properties of multi-layer PVA nanofiber textiles. The particles of a diameter equal to 5 nm were incorporated into double- and ...
Fabrication of 3D diamond membranes for microfluidic systems
Varga, Marián; Babchenko, Oleg; Bauerová, Pavla; Hruška, Karel; Jurka, Vlastimil; Kromka, Alexander; Rezek, Bohuslav
2015 - anglický
Perfusion of cell medium, especially in microfluidic devices, can provide in-vivo-like conditions for cell cultures. The most recent demand on such systems is to include electronically active artificial cell support for in-situ monitoring. Diamond thin films exhibit advantageous combination of physical, mechanical, chemical, biocompatible and electronic properties for this purpose. In this work we explore two strategies for fabrication of self-standing three-dimensional nanocrystalline diamond membrane for implementation in microfluidic invivo like experiments: i) nucleation and chemical vapour deposition (CVD) growth of diamond on porous 3D carbon foam (with 80 pores per inch) and ii) selective diamond growth predefined by photolithographic processing using copper grid mask. The morphology and material quality of the fabricated membranes are characterized by scanning electron microscopy and Raman spectroscopy.
Klíčová slova:
nanocrystalline diamond; membranes; microwave plasma; microfluidics; carbon foam
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Fabrication of 3D diamond membranes for microfluidic systems
Perfusion of cell medium, especially in microfluidic devices, can provide in-vivo-like conditions for cell cultures. The most recent demand on such systems is to include electronically active ...
(100) substrate processing optimization for fabrication of smooth boron doped epitaxial diamond layer by PE CVD
Mortet, Vincent; Fekete, Ladislav; Ashcheulov, Petr; Taylor, Andrew; Hubík, Pavel; Trémouilles, D.; Bedel-Pereira, E.
2015 - anglický
Boron doped diamond layers were grown in an SEKI AX5010 microwave plasma enhanced chemical vapour deposition system. Effect of surface preparation, i.e. polishing and O2/H2 plasma etching on epitaxial growth on type Ib (100) HPHT synthetic diamonds were investigated. Using optimized substrate preparation, smooth (RRMS ~ 1 nm) boron doped diamond layers with metallic conduction and free of un-epitaxial crystallites were grown with a relatively high growth rate of 3.7 μm/h. Diamond were characterized by optical microscopy, optical profilometry, atomic force microscopy and Hall effect.
Klíčová slova:
doping; PE CVD; diamond; surface treatment; thin film
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
(100) substrate processing optimization for fabrication of smooth boron doped epitaxial diamond layer by PE CVD
Boron doped diamond layers were grown in an SEKI AX5010 microwave plasma enhanced chemical vapour deposition system. Effect of surface preparation, i.e. polishing and O2/H2 plasma etching on epitaxial ...
Doped DLC coatings for biomedical applications
Písařík, Petr
2015 - anglický
Nowadays there are materials having excellent properties for use in medicine (Diamond-like carbon, Hydroxyapatite, …). Diamond-like carbon (DLC) is a metastable form of amorphous carbon containing bonded carbon atoms of sp2 and sp3 hybridized orbital. DLC layers are semiconductors with high mechanical hardness, chemical inertness, low coefficient of friction, high thermal conductivity, good electrical and optical properties, biocompatibility and no cytotoxicity. All properties of the films are not always ideal, so it is necessary to modify the layer. One example of how to modify the properties of thin layers are dopations. The incorporation of dopants in films may lead to greater multifunctionality and much improved properties. Most modifications were made to modify contact angle and surface energy, to reduce internal stresses, to decrease surface roughness, coefficient of friction or wear....
Klíčová slova:
silver doped; diamond like carbon; thin layers; mechanical properties
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Doped DLC coatings for biomedical applications
Nowadays there are materials having excellent properties for use in medicine (Diamond-like carbon, Hydroxyapatite, …). Diamond-like carbon (DLC) is a metastable form of amorphous carbon containing ...
Initial study of structure of nanofiber textiles and the creation of its model
Havrlík, M.; Sveshnikov, Alexey
2015 - anglický
In this research, the structure of the fabrics was analyzed using an electron scanning microscope Tescan Maia 3. Two sets of the experiments have been carried out. In the first experiment the surface structure of the samples was studied. Photos created by SEM were analyzed using program Atlas and image editor GIMP. In this set of the experiments the initial parameters for the creation of a digital 2D model of a single layer have been determined (fiber size distribution, pore size and curvature of the fibers). In the second set of the experiments cross sections of nanofiber textiles were made in order to study the inner structure of the fabric. This information allows evaluation of the total number of 2D layers in the model and, thus, is very important for future creation of a 3D model of the fabric.
Klíčová slova:
polymer; SEM photography
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Initial study of structure of nanofiber textiles and the creation of its model
In this research, the structure of the fabrics was analyzed using an electron scanning microscope Tescan Maia 3. Two sets of the experiments have been carried out. In the first experiment the surface ...
Nanomechanical testing of an a-C:N nanolayer prepared by ion beam assisted deposition on Ti.sub.6./sub.Al.sub.4./sub.V alloy
Vlčák, P.; Šepitka, J.; Horaždovský, T.; Jirka, Ivan; Gregora, Ivan; Němec, M.
2015 - anglický
We applied ion beam assisted deposition for preparing a-C:N nanolayers on Ti6Al4V alloy. A Hysitron TI 950 TriboIndenter (TM) nanomechanical test instrument was used to assess the depth profiles of the mechanical properties on modified titanium substrates. Two methods were employed : a) quasistatic partial unload, and b) dynamic Continuous Measurement of X (CMX). The average nanoindentation hardness increased from HIT similar to 5GPa for a reference sample to HIT similar to 8.6 GPa for a sample coated by an a-C nanolayer, and to HIT similar to 11.5 GPa for a sample coated by an a-C:N nanolayer. The average storage modulus of the sample coated by a-C:N increased from E' similar to 130 GPa (reference sample) to E' similar to 155 GPa. The storage modulus of the sample coated by the a-C nanolayer was less than the storage modulus of the titanium substrate.
Klíčová slova:
carbon-based materials; hardness; ion beam assisted deposition; a-C:N nanolayer
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Nanomechanical testing of an a-C:N nanolayer prepared by ion beam assisted deposition on Ti.sub.6./sub.Al.sub.4./sub.V alloy
We applied ion beam assisted deposition for preparing a-C:N nanolayers on Ti6Al4V alloy. A Hysitron TI 950 TriboIndenter (TM) nanomechanical test instrument was used to assess the depth profiles of ...
Computational study of cellular assembly on hydrophobic/hydrophilic micro-patterns
Ukraintsev, Egor; Brož, A.; Kalbáčová, M.H.; Kromka, Alexander; Rezek, Bohuslav
2015 - anglický
We develop simple onedimensional stochastic model of cell behavior on chemically patterned surfaces that is based on three key parameters: speed of cell movement (motility) across substrate, probability of cell adhesion to substrate, and probability of cell division on substrate when adhered on substrate. Amount of adhered cells on hydrophobic and hydrophilic regions is calculated as function of time (number of cycles up to 2000). The model is correlated with in-vitro data obtained within 48 h in real time. We show that this simple stochastic model with the three parameters (where cell motility is the most important one) can describe with high accuracy the experimental data and thereby explain the observed preferential cell assembly on hydrophilic/hydrophobic micro-patterns (up to 200 um width).
Klíčová slova:
SAOS-2 cells; cell movement; adhesion; stochastic computer simulations
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Computational study of cellular assembly on hydrophobic/hydrophilic micro-patterns
We develop simple onedimensional stochastic model of cell behavior on chemically patterned surfaces that is based on three key parameters: speed of cell movement (motility) across substrate, ...
NUŠL poskytuje centrální přístup k informacím o šedé literatuře vznikající v ČR v oblastech vědy, výzkumu a vzdělávání. Více informací o šedé literatuře a NUŠL najdete na webu služby.
Vaše náměty a připomínky posílejte na email nusl@techlib.cz
Provozovatel
Zahraniční báze