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Sub-Nanosecond Laser Induced Plasma as Water Window Radiation Source.
Vrbová, M.; Vrba, Pavel
2017 - English
Laser plasma created in a krypton gas puff target is studied as a source of radiation in the water window spectral range (lambda= 2.3 - 4.4 nm). The spatial development of the plasma induced by a sub-nanosecond Nd:YAG laser pulse focused on the gas puff target is modeled using 2d RMHD code Z*. Space-time distributions of plasma quantities, namely electron temperature, electron density, mass density and plasma expansion velocity were evaluated. Instantaneous spectra during the laser pulse and during plasma decay period are also calculated. Temporal evolutions of the krypton ions relative populations prove that ions from Kr21+ and Kr22+ are responsible for dominant spectral intensity emitted at a wavelength around lambda= 3 nm. Evaluated time resolved spectra are compared with time integrated spectra obtained experimentally.
Keywords:
RMHD simulations; gas puff; laser plasma water window sources
Available at various institutes of the ASCR
Sub-Nanosecond Laser Induced Plasma as Water Window Radiation Source.
Laser plasma created in a krypton gas puff target is studied as a source of radiation in the water window spectral range (lambda= 2.3 - 4.4 nm). The spatial development of the plasma induced by a ...
Deformation of thin self-standing mask at inhomogeneous irradiation.
Koláček, Karel; Schmidt, Jiří; Frolov, Oleksandr; Štraus, Jaroslav; Chalupský, Jaromír; Choukourov, A.
2017 - English
Flatness of the mask is one of key features influencing the quality of image. Among factors that can affect mask flatness belongs inhomogeneous illumination. This does not apply to lithography, but to experiments that use only discrete parts of mask e.g. for nanostructuring or other type of material research. It is shown that even single EUV laser shot (laser wavelength ~46.9 nm, pulse duration ~1.5 ns, focused pulse energy ~20 .mu.J, peak fluency 48 J/cm2) not only deforms the mask, but also changes mask-substrate distance. In our case two kinds of grids (one circular with rectangular windows 7.5x7.5 μm and bars 5 micro m (period 12.5x12.5 micro m), other rectangular with rectangular windows 3.2x1.2 μm and bars 0.8 micro m (period 4x2 micro m)) were attached to PMMA substrate and exposed to one or five superimposed focused laser shots. The mask (grid) deformation was inferred from the changes of diffraction pattern engraved into PMMA.
Keywords:
interaction of XUV radiation with solid surface; nanostructuring; nanopatterning; XUV diffraction
Available at various institutes of the ASCR
Deformation of thin self-standing mask at inhomogeneous irradiation.
Flatness of the mask is one of key features influencing the quality of image. Among factors that can affect mask flatness belongs inhomogeneous illumination. This does not apply to lithography, but to ...
The role of pre-ionization on EUV capillary laser profile.
Štraus, Jaroslav; Schmidt, Jiří; Koláček, Karel; Frolov, Oleksandr
2017 - English
The profile of EUV capillary laser beam was believed to be an annulus and a corresponding theory for its explanation was generally accepted. Nevertheless, our recent detailed observation shows, that the laser profile can be remarkably influenced by the parameters of pre-pulse, serving for working gas pre-ionisation before introduction the main current into the capillary. The examples of possible profile shapes and corresponding parameters are presented.
Keywords:
Pre-pulse; capillary XUV laser beam profile
Available at various institutes of the ASCR
The role of pre-ionization on EUV capillary laser profile.
The profile of EUV capillary laser beam was believed to be an annulus and a corresponding theory for its explanation was generally accepted. Nevertheless, our recent detailed observation shows, that ...
Application of Electric Probes for Study of Structure of Thermal Plasma Jet.
Hurba, Oleksiy; Hrabovský, Milan
2017 - English
Thermal plasma at atmospheric pressure was investigated. Electric probes and doable probe used as relatively simple and efficient tool for diagnostic of structure of flow field in thermal plasma jet. Were defined plasma potential and boundaries of the conducting region and their changing for the diferent operating modes of plasma torch.
Keywords:
Electric probes; double probe; thermal; plasma jet
Available at various institutes of the ASCR
Application of Electric Probes for Study of Structure of Thermal Plasma Jet.
Thermal plasma at atmospheric pressure was investigated. Electric probes and doable probe used as relatively simple and efficient tool for diagnostic of structure of flow field in thermal plasma jet. ...
Simulace zbytkových optických vad objektivu Merz 124/1477
Rail, Zdeněk; Melich, Zbyněk; Šrajer, Bohdan
2017 - Czech
Tento objektiv byl na Ústavu fyziky plazmatu,v.v.i., Centru Toptec v Turnově restaurován. Během tohoto procesu jsme získali možnost objektiv na optické lavici přeměřit a vyčíslit jeho zbytkové optické vady. Objektiv byl vyroben kolem roku 1860-1870. This objective lens was renoved in the Institute of Plasma Physics, v.v.i. Center Toptec in Turnov. During the process we got a possibility to measure the objective lens on the optical bench and to evaluate its residual optical aberrations. The objective lens was manufactured in 1860-1870 years
Keywords:
Achromatic dublet; spherochromatic aberration; coma; dispersion curve of glass; B-F chromatic correction
Available at various institutes of the ASCR
Simulace zbytkových optických vad objektivu Merz 124/1477
Tento objektiv byl na Ústavu fyziky plazmatu,v.v.i., Centru Toptec v Turnově restaurován. Během tohoto procesu jsme získali možnost objektiv na optické lavici přeměřit a vyčíslit jeho zbytkové optické ...
Optické parametry význačných refraktorů
Rail, Zdeněk; Jareš, Daniel; Pintr, Pavel; Vápenka, David
2017 - Czech
V tomto referátu publikujeme optické parametry několika historických dalekohledů, které jsme v literatuře a na webových stránkách získali. Data byla vložena do optického programu ZEMAX, v němž byly vyčísleny jejich zbytkové vady. In this paper we publish the optical parameters of several historic telescopes, which we have found in scientific literature or web pages. Data were inputed into the optical program ZEMAX, which evaluated their residual aberrations.
Keywords:
Achromatic objective lens; spherochromatic aberration; coma; residual chromatic aberration; Index of refraction; dispersion curve of glass
Available at various institutes of the ASCR
Optické parametry význačných refraktorů
V tomto referátu publikujeme optické parametry několika historických dalekohledů, které jsme v literatuře a na webových stránkách získali. Data byla vložena do optického programu ZEMAX, v němž byly ...
Material design problems of plasma-chemical reactors for disposal perfluorinated compounds
Brožek, Vlastimil; Březina, Václav; Mastný, L.; Kubatík, Tomáš František; Živný, Oldřich
2017 - English
Reduction of perfluorinated gases emissions from semiconductor industry has recently introduced a serious problem from both technological and economic side. With respect to chemistry of the decomposition reactions the most effective abatement techniques developed up to now consists in the interaction of those gaseous pollutants with several types of plasmas. In the framework of Czech-Taiwanese bilateral project No. 17-10246J 'Decomposition of Perfluorinated Compounds and Fluorinated Ozone Depleting Substances' a new plasmochemical reactor design is to be solved. In this reactor the plasma abatement process consisting of interaction of the plasma generated by unique watter stabilized H-WSP plasma torch at temperatures ranging\nfrom 2000 K up to 25,000 K with the treated gases will be carried out. However, the main product generated in the reactor during the steam plasma abatement process is hydrogen fluoride which causes corrosion of almost every construction material. The aim pursued by the work presented is to search for the materials resistant to exposition of HF even at high temperatures. To investigate corrosion resistance of construction materials with thermal stability within temperature interval 2700-3000 °C titan nitride, boron nitride, and silicon carbide have been selected. The samples of those materials have been prepared by spark plasma sintering method and exposed to concentrated solution of hydrofluoric acid for which corrosion rates have been measured
Keywords:
perfluorinated compounds; thermal plasma torch; boron nitride; titanium nitride; silicon carbide
Available at various institutes of the ASCR
Material design problems of plasma-chemical reactors for disposal perfluorinated compounds
Reduction of perfluorinated gases emissions from semiconductor industry has recently introduced a serious problem from both technological and economic side. With respect to chemistry of the ...
ADHESION OF BIOCOMPATIBLE TiNb COATING
Kolegar, T.; Matoušek, M.; Vilémová, Monika; Starý, V.
2017 - English
Preparation of a coating with a high quality requires good adhesion of the film to the substrate. The paper deals with the adhesion of biocompatible TiNb coating with different base materials. Several materials such as titanium CP grade 2, titanium alloys Ti6Al4V and stainless steel AISI 316L were measured. Testing samples were made in the shape of small discs. Those samples were coated with a TiNb layer by using the PVD method (magnetron sputtering). Onto the measured layer of TiNb an assistant cylinder was stuck using a high strength epoxy adhesive E1100S. The sample with the assistant cylinder was fixed into a special fixture and the whole assembly underwent pull-off testing for adhesion. The main result of this experiment was determining the strength needed to peel the layer and morphology and size of the breakaway. As a result, we will be able to determine the best base material and conditions where the coating will be remain intact with the base material.
Keywords:
PVD coating; Adhesion; Biocompatible materials; Pull-off test; Titanium; Niobium
Available at various institutes of the ASCR
ADHESION OF BIOCOMPATIBLE TiNb COATING
Preparation of a coating with a high quality requires good adhesion of the film to the substrate. The paper deals with the adhesion of biocompatible TiNb coating with different base materials. Several ...
Investigation of nanosecond pulsed corona-like discharge generated in deionized water.
Pongrác, Branislav; Šimek, Milan; Babický, Václav; Člupek, Martin; Lukeš, Petr
2017 - English
We employed techniques of time–resolved ICCD microscopy and spectroscopy to register basic morphologic and emission fingerprints of micro-discharges produced in deionized water.
Keywords:
Underwater discharge; nanosecond pulsed discharge; time-resolved emission spectroscopy; time-resolved ICCD imaging
Available at various institutes of the ASCR
Investigation of nanosecond pulsed corona-like discharge generated in deionized water.
We employed techniques of time–resolved ICCD microscopy and spectroscopy to register basic morphologic and emission fingerprints of micro-discharges produced in deionized water.
FÁZOVÁ STABILITA Y2O3 A W-Y2O3 ZPRACOVANÝCH METODOU MECHANICKÉHO LEGOVÁNÍ.
Illková, Ksenia; Vilémová, Monika; Lukáč, František
2017 - Czech
Kinetika fázových transformací B -> C jak v samotném Y2O3 tak i ve slitině W-xY2O3 je velmi důležitá vzhledem k použití těchto materiálů ve vysokoteplotních aplikacích. Chování vysokotlaké fáze B práškového Y2O3 indukované mletím a vlastnosti kompozitu W-Y2O3 byly studovány pomocí diferenční termální analýzy a rentgenové difrakce. Bylo zjištěno, že fázová stabilita je výrazně závislá na rychlosti ohřevu a na době setrvání na dané teplotě. Properties of milling-induced high-pressure B phase in Y2O3 and W-Y2O3 powders were studied by differential thermal analysis and X-Ray diffraction. It was found that phase stability strongly depends on the heating rate and holding time.
Keywords:
yttrium oxide; tungsten; milling; differential thermal analysis
Available at various institutes of the ASCR
FÁZOVÁ STABILITA Y2O3 A W-Y2O3 ZPRACOVANÝCH METODOU MECHANICKÉHO LEGOVÁNÍ.
Kinetika fázových transformací B -> C jak v samotném Y2O3 tak i ve slitině W-xY2O3 je velmi důležitá vzhledem k použití těchto materiálů ve vysokoteplotních aplikacích. Chování vysokotlaké fáze B ...
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