No (543)
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543
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Reflectivity of a mirror in XUV spectral region (46.9 nm).
Schmidt, Jiří; Koláček, Karel; Štraus, Jaroslav; Frolov, Oleksandr; Prukner, Václav; Melich, Radek; Psota, Pavel; Sobota, Jaroslav; Fořt, Tomáš
2017 - English
A focusing mirror as an optical element is used in our applications that require light collection (e.g. for laser ablation studies). A knowledge of the mirror reflectivity is important for determination of focused laser pulse energy, or for determination of local fluencies near the laser focus. The reflectivity of our spherical focusing mirror with(/without) multi-layer coating was measured. Reflection coefficients of this mirror in a long period of time are also reported. Further, the incidence-angle dependence of the XUV reflectivity of flat mirrors is presented as well.
Keywords:
Reflectivity of multilayer mirror in XUV range; aging of multilayer mirrors
Available at various institutes of the ASCR
Reflectivity of a mirror in XUV spectral region (46.9 nm).
A focusing mirror as an optical element is used in our applications that require light collection (e.g. for laser ablation studies). A knowledge of the mirror reflectivity is important for ...
Double pulse capillary discharge assessment for nitrogen soft X-ray laser.
Hübner, Jakub; Nevrkla, M.
2017 - English
The work examines possibilities of capillary discharge pinching plasma driven by combination of two electric current pulses ("pedestal" slow exponentially damped sinus t1/4 > 200 ns, peak current Ipeak < 50 kA and fast triangular pulse with a rise time about 38 ns, Ipeak > 60 kA) to obtain the maximum possible gain at wavelength l = 13.4 nm (hydrogen-like nitrogen recombination scheme). The optimal initial density ρ0 (or pressure) and start time tstart of second triangular pulse (second pulse start at peak current Ipeak of the first pulse) were determined for two capillary radii (0.5 and 1 cm) and four current peaks of the first pulse (20, 30, 40 and 50 kA).\n
Keywords:
capillary discharge; XUV laser; pinch dynamics; nitrogen recombination schema; ablation
Available at various institutes of the ASCR
Double pulse capillary discharge assessment for nitrogen soft X-ray laser.
The work examines possibilities of capillary discharge pinching plasma driven by combination of two electric current pulses ("pedestal" slow exponentially damped sinus t1/4 > 200 ns, peak current ...
Maksutovovy soustavy z Turnova
Rail, Zdeněk; Melich, Zbyněk; Jareš, Daniel; Pintr, Pavel; Vápenka, David
2017 - Czech
Tento referát popisuje vývoj a výrobu optických soustav, u kterých byl použit meniskový korektor Maksutova jako vstupní člen. Řada těchto vysoce kvalitních systémů byla v Turnově vyráběna od sedmdesátých let na několika pracovištích. V naší práci presentujeme zkušenosti s optickým designem, výrobou a konstrukcí meniskových dalekohledů a komor. This paper deals of a design and a manufacture of optical systems with the entrance meniscus corrector of Maksutov. Many of these high performance systems have been manufactured in several workshops in Turnov since Seventies. We present our experience with the optical design, manufacture and construction of the meniscus telescopes and cameras in this article.
Keywords:
Catadioptric system; meniscus corrector; spherochromatic aberration; spherical aberration; coma; astigmatism; Petzval´s curvature; MTF curve; glass dispersion curve
Available at various institutes of the ASCR
Maksutovovy soustavy z Turnova
Tento referát popisuje vývoj a výrobu optických soustav, u kterých byl použit meniskový korektor Maksutova jako vstupní člen. Řada těchto vysoce kvalitních systémů byla v Turnově vyráběna od ...
NATAP – leštění CNT kompozitů
Thoř, Tomáš
2017 - Czech
Zkoumané vzorky jsou uhlíkový kompozitní materiál složený z kyanoesterové pryskyřice (matrice), uhlíkových vláken (ve formě tkaniny) a vrstvy uhlíkových nanotrubic (ve formě bucky paperu). Zpráva obsahuje popis vývoje leštění tohoto materiálu na podložce z PU v kombinaci s leštivem CeO2. Examined samples are of carbon composite material composed of a cyanoester resin (matrix), carbon fibers (in the form of a fabric) and a carbon nanotube layer (in the form of a piece of paper). The report contains a description of the development of polishing such material on a PU polishing pad in combination with a CeO2 slurry.
Keywords:
cnt composite; polishing; optical; polyurethane
Available at various institutes of the ASCR
NATAP – leštění CNT kompozitů
Zkoumané vzorky jsou uhlíkový kompozitní materiál složený z kyanoesterové pryskyřice (matrice), uhlíkových vláken (ve formě tkaniny) a vrstvy uhlíkových nanotrubic (ve formě bucky paperu). Zpráva ...
Pokročilé optické systémy s využitím asférických ploch: Odborná zpráva projektu – naplnění dílčích cílů 2016
Matoušek, Ondřej; Melich, Radek; Procháska, František; Tomka, David; Provazníková, P.; Polzer, J.; Fogelton, P.
2017 - Czech
Odborná zpráva projektu dokumentuje dosažení dílčího cíle projektu pro rok 2016, kterým byla standardizace celého výrobního procesního řetězce zahrnující návrh, výrobu a měření. The expert report of the project documents the achievement of the partial project objective for 2016, which was the standardization of the all production process chain including design, production and measurement.
Keywords:
asphere; process; chain; standardization
Available at various institutes of the ASCR
Pokročilé optické systémy s využitím asférických ploch: Odborná zpráva projektu – naplnění dílčích cílů 2016
Odborná zpráva projektu dokumentuje dosažení dílčího cíle projektu pro rok 2016, kterým byla standardizace celého výrobního procesního řetězce zahrnující návrh, výrobu a měření....
AAS - test readiness review
Budasz, Jiří; Lédl, Vít; Pleštil, Jan; Steiger, Lukáš; Václavík, Jan; Veselý, Martin
2017 - English
This document describes the test procedure applicable to the electrical and functional tests of the Alignment Aid System.\nThe test to be performed according to this procedure are to demonstrate the compliance of the above item to the requirements specified in the applicable document as part of the overall verification program. The test results shall be collected in a Test Report.
Keywords:
laser; mirror; reference; measurement
Available on request at various institutes of the ASCR
AAS - test readiness review
This document describes the test procedure applicable to the electrical and functional tests of the Alignment Aid System.\nThe test to be performed according to this procedure are to demonstrate the ...
Preparation of spheroidized and nano-structural spinels by the SPPS method
Brožek, Vlastimil; Lukáč, František; Medřický, Jan; Mušálek, Radek; Mašláni, Alan; Mastný, L.; Brodil, R.
2017 - English
Solution Precursor Plasma Spraying (SPPS) method, using hybrid water-stabilised plasma torch (WSP®-H), is presented in this study. Precursor, in a form of a solution of inorganic salts, is injected into the plasma jet, where the temperature can reach up to 25 000 K and a series of reactions lead to the formation of spherical sub-micrometric sized particles. The complete process of evaporating the liquid, crystallization, thermic decomposition, melting and recrystallization takes place in few milliseconds before the particles solidify. Melted nanoparticles can be either directly collected in order to obtain ultrafine powders or deposited onto a substrate to form micro-splats and continuous polycrystalline, and often partially amorphous, coatings. The possibility of continuous and discontinuous changes of stoichiometric composition in tetrahedral and octahedral configurations were analysed for the deposits of MgAl2O4, CoAl2O4 and CoFe2O4 spinels. Furthermore, thin colourful coatings of ruby and modified cobalt oxides were deposited onto ceramic and metallic substrates.
Keywords:
Solution plasma spraying; suspension plasma spraying; spinels; ferrites; ruby; nanoparticles
Available at various institutes of the ASCR
Preparation of spheroidized and nano-structural spinels by the SPPS method
Solution Precursor Plasma Spraying (SPPS) method, using hybrid water-stabilised plasma torch (WSP®-H), is presented in this study. Precursor, in a form of a solution of inorganic salts, is injected ...
On tungsten spraying using inductively coupled plasma system - First results
Klečka, Jakub; Mušálek, Radek; Vilémová, Monika; Lukáč, František
2017 - English
Thanks to its unique properties such as high melting point and density, tungsten and tungsten-based alloys are commonly used in a wide range of applications. Among others, these materials are promising candidates for the plasma facing components in the future fusion reactors. One of considered ways of production of these parts is plasma spraying. There are however several limitations for conventional gas stabilized torches, mainly in plasma enthalpy (i.e. the ability to efficiently melt tungsten particles in considerable feed rates) and susceptibility of tungsten to oxidation (which complicates spraying in oxidizing open-air atmosphere). The radio frequency inductively coupled plasma torch (RF-ICP) is a unique system which can potentially overcome both these problems and can be used for efficient tungsten spraying. The tungsten powder, which can be finer than the one used for the conventional systems, is fed axially into the hot plasma core, both factors lead to a more efficient melting of the particles. The deposition is performed in a chamber with controlled atmosphere of inert gas or decreased pressure, the oxidation is therefore suppressed. In this first study carried out with the newly commissioned RF-ICP system TekSpray 15 (Tekna), samples of tungsten coatings on graphite substrates were prepared. The X-ray diffraction and SEM images of the free surfaces and cross-sections were obtained, documenting high purity of the deposits and appropriate flattening of the splats leading to a dense coating microstructure. The effect of substrate preheating on the microstructure, porosity and hardness was also studied.
Keywords:
Radio frequency inductively coupled plasma torch; tungsten; plasma facing components; plasma spraying
Available at various institutes of the ASCR
On tungsten spraying using inductively coupled plasma system - First results
Thanks to its unique properties such as high melting point and density, tungsten and tungsten-based alloys are commonly used in a wide range of applications. Among others, these materials are ...
Combined coatings against mechanical wear and corrosion low carbon steel
Brožek, Vlastimil; Pokorný, P.; Kolísko, J.; Vokáč, M.; Mastný, L.; Stoulil, J.
2017 - English
In this study, special ceramic coatings were prepared on low carbon steel (1.0060 - EN 10027-2) via the plasma spraying technique using a WSP®-H plasma generator with output of up to 40 kg/h of aluminum oxide. Corundum coatings were deposited directly on the surface of steel plungers equipped with an anti-corrosion interlayer of zinc phosphate. Coating adhesion properties were tested using pin-off tests (modified ISO 4624) and reached a maximum value of 26 MPa. Corrosion resistance was evaluated by measurements of impedance spectra in the 100 kHz - 10 mHz range in a water solution of sodium sulfate. The capacity of electric double-layer varied depending on the porosity and thickness of the coating. Low-porosity coatings of >1.5 mm thickness had RCT 1.29·105 Ω·m2. The abrasive resistance of coatings was measured by rotary/machining test with SiC cutting knives, using a downforce of 50 kg·cm-2. Abrasion losses decreased with the quality of finish - starting at 0.00266 g cm-2 min-1 down to virtually zero losses after polishing the surface below Ra = 0.55 micro m.
Keywords:
Abrasion; Ceramic coatings; Corrosion resistance; Plasma spraying; Steel phosphating
Available at various institutes of the ASCR
Combined coatings against mechanical wear and corrosion low carbon steel
In this study, special ceramic coatings were prepared on low carbon steel (1.0060 - EN 10027-2) via the plasma spraying technique using a WSP®-H plasma generator with output of up to 40 kg/h of ...
Suspension plasma spraying of sub-stoichiometric titania by hybrid water/argon stabilized plasma torch
Mušálek, Radek; Ctibor, Pavel; Medřický, Jan; Tesař, Tomáš; Kotlan, Jiří; Lukáč, František
2017 - English
In this study, suspension plasma spraying of sub-stoichiometric titania was attempted using hybrid water/argon stabilized plasma torch (WSP-H). Porous coatings with fine cauliflower-like columnar microstructure were successfully deposited in two separate experiments with different power levels of the plasma torch. In both cases, high solid-load content (40 wt. %) of the water-based suspension resulted in considerable coating thickness increase per deposition cycle. Coating annealing and partial remelting of the surface asperities were also achieved by additional pass of plasma torch in front of the coating surface. According to X-ray diffraction, all coatings consisted dominantly of rutile phase. Detailed microscopic observation of the as-sprayed and annealed deposits showed that the local coloration of the coating (ranging from dark blue to beige) was driven by the local overheating of the rough coating surface which could also promote the oxygen intake. Moreover, sample annealing was also observed to increase the sample reflectivity as observed by UV-VIS-NIR scanning spectrophotometry
Keywords:
Liquid feedstock; Plasma spraying; Suspension; Thermal spraying; Titania; WSP-H
Available at various institutes of the ASCR
Suspension plasma spraying of sub-stoichiometric titania by hybrid water/argon stabilized plasma torch
In this study, suspension plasma spraying of sub-stoichiometric titania was attempted using hybrid water/argon stabilized plasma torch (WSP-H). Porous coatings with fine cauliflower-like columnar ...
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