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Thermal plasma gasification of organic waste and biomass
Hrabovský, Milan
2013 - English
The paper presents description of thermal plasma gasification processes. Analysis of energy balances of plasma gasification is presented, kinetics of the gasification process is discussed and relations between particle size, reaction temperature and gasification rate are analyzed. Examples of results of gasification of biomass and pyrolysis oil from used tires are given. Syngas with high heating value, high hydrogen content and low tar contamination is produced by plasma gasification.
Keywords:
Thermal plasma; plasma gasification; syngas
Available at various institutes of the ASCR
Thermal plasma gasification of organic waste and biomass
The paper presents description of thermal plasma gasification processes. Analysis of energy balances of plasma gasification is presented, kinetics of the gasification process is discussed and ...
Analýza emisních čar ve výboji v napařovacím stroji
Oupický, Pavel; Sember, Viktor
2013 - Czech
Referát stručně popisuje měření spektra doutnavého výboje v napařovacím stroji a určování složení plynného prostředí, teploty a hustoty částic. This paper simply describe the measuring of spectra of glow discharge in coating machine and the determination of the gas composition and the temperature and density of its particles.
Keywords:
Glow discharge; emission lines; spectra; measuring; gas; temperature
Available at various institutes of the ASCR
Analýza emisních čar ve výboji v napařovacím stroji
Referát stručně popisuje měření spektra doutnavého výboje v napařovacím stroji a určování složení plynného prostředí, teploty a hustoty částic....
Interakce chalkogenidových skel typu Ge-As-Se s hexagonálním nitridem boritým
Mastný, L.; Matušek, M.; Randáková, S.; Brožek, Vlastimil
2013 - Czech
Chalkogenidová skla na bázi Ge-As-Se pro aplikace v infračervené optice mohou obsahovat jen stopová množství kyslíku, protože vazby typu Ge-O a As-O způsobují v oblastech vlnových délek kolem 12,8 μm absorpční pásy, které snižují optickou propustnost chalkogenidových skel. Chalkogenidová skla se proto připravují buď v evakuovaných nádobách nebo v inertní atmosféře v nádobách z vysoce kvalitního křemene, který je speciálně kondiciován, aby se nestal sám zdrojem kyslíkových nečistot. Tyto křemenné nádoby jsou velmi drahé. Cílem této práce je ukázat, že lze chalkogenidová skla syntetizovat i v nádobách zhotovených z turbostratického hexagonálního nitridu boritého rafinovaného reduktivní halogenací ve směsi trichlormethanu a amoniaku. Chalcogenide glasses on the base Ge-As-Se for the applications in infrared optics may content only trace amount of oxygen, because the chemical bonds of the type Ge-O and As-O induce in chalcogenide glasses the generation of absorption bands at the wavelength about 12.8 μm with the consequence of the lowering of optical transmittance of chalcogenide glasses. That is why the chalcogenide glasses must be synthesized in the tubes from special conditioned quartz for to avoid the quartz will be the source of oxygen impurities. The tubes from this quartz are very expensive. The aim of this works is to point out that the chalcogenide glasses may be synthesized also in the tubes from turbostratic hexagonal boron nitride which is refined in the mixture of trichloromethane and ammonia.
Keywords:
Chalcogenide glasses; turbostratic boron nitride; boron nitride crucibles; boron nitride dezoxidation
Available at various institutes of the ASCR
Interakce chalkogenidových skel typu Ge-As-Se s hexagonálním nitridem boritým
Chalkogenidová skla na bázi Ge-As-Se pro aplikace v infračervené optice mohou obsahovat jen stopová množství kyslíku, protože vazby typu Ge-O a As-O způsobují v oblastech vlnových délek kolem 12,8 μm ...
Plazmové povlakování fosfátovaných ocelí II
Pokorný, P.; Mastný, L.; Brožek, Vlastimil
2013 - Czech
Příspěvek navazuje na úvodní část, prezentovanou na konferenci APROCHEM 2012 a zabývá se možností využití různých druhů fosfátových povlaků při předúpravě běžné nelegované oceli určené k plazmovému nástřiku keramiky. Úkolem konverzního fosfátového povlaku je vylepšit korozní odolnost povlakované oceli a zároveň vylepšit a prodloužit adhezi keramiky k ocelovému podkladu. Výběr nejvhodnějšího fosfátového povlaku (zinečnaté, zinečnato-vápenaté, manganaté a „tříkationtové“ fosfátování) byl založen na studiu jejich dehydratačních křivek prostřednictvím DTA a TGA analýzy s následnou analýzou morfologie, integrity a složení povlaku po jednotlivých dehydratačních krocích. Vzorky byly exponovány při 200 °C po dobu 10 hodin. Z výsledků měření vyplynulo, že nejstabilnější je manganatý fosfát. Plazmová depozice korundu byla realizována pomocí generátoru nízkoteplotního plazmatu WSP®. Korozní odolnost jednotlivých povlakovaných vzorků s rozdílnými fosfátovými mezivrstvami byla ověřována měřením This article follows the introductory part, presented at the conference APROCHEM 2012 and evaluates the possibility of using different kind of phosphate coatings for the pretreatment of mild steel intended for plasma sprayed ceramic coatings. The phosphate conversion coating has to improve the corrosion resistance of coated steel and also to improve and extend the adhesion of ceramic coating to mild steel surface. Selection the most appropriate phosphate coating (zinc, zinc-calcium, manganese and „three-cations“ phosphate) was established to study the dehydration curves by means of DTA and TGA analysis with subsequent analysis of morphology, integrity and composition of the coating after each dehydration section.Samples were exposed at 200 °C for 10 hours.The measurement results showed that the most stable is manganese phosphate. Plasma deposition of corundum was carried out low-temperature plasma generator WSP ®. The corrosion resistance of coated samples with different phosphate
Keywords:
Surface treatment; phosphating coatings; bond strength; plasma spraying; ceramic coatings
Available at various institutes of the ASCR
Plazmové povlakování fosfátovaných ocelí II
Příspěvek navazuje na úvodní část, prezentovanou na konferenci APROCHEM 2012 a zabývá se možností využití různých druhů fosfátových povlaků při předúpravě běžné nelegované oceli určené k plazmovému ...
Comparison of holographic setups used in heat and mass transfer measurement
Doleček, Roman; Psota, Pavel; Lédl, Vít; Vít, Tomáš; Kopecký, V.
2013 - English
The authors of the paper deal with measurement of heat and mass transfer for several years and they have frequently used few techniqes for measurement of refractive index distribution based on holographic interferometry. Some of the well known techniques have been modified some and some new ones developped. Every technique could be applied with success in different type of meassurement and obviously every one has set of properties making them unique. We decided to digest few different basic techniques and describe its properties in this paper with the aim to help the reader select the proper one for their measurement. The list of techniques and its properties is not comprehensive but schould serve as a basic orientation in the field.
Keywords:
Digital holography; Holographic setup; Heat and mass transfer measurement
Available at various institutes of the ASCR
Comparison of holographic setups used in heat and mass transfer measurement
The authors of the paper deal with measurement of heat and mass transfer for several years and they have frequently used few techniqes for measurement of refractive index distribution based on ...
Measurement of Vibration Mode Structure for Adaptive Vibration Suppression System by Digital Holography
Psota, Pavel; Lédl, Vít; Doleček, Roman; Mokrý, P.; Kopecký, V.
2013 - English
Previously the frequency-shifted digital holographic interferometry (FSDHI) for measurement of vibration amplitudes in range of nanometers was introduced and verified by authors [1,2]. The method FSDHI addressed some of the drawbacks of the conventional methods and was used mainly for piezoelectric transformer vibration amplitudes and mode structures measurement [3]. The limiting factor for application of this method is the maximal measured value of the vibration amplitude without the risk of ambiguity. The value is approximately 80nm for the frequency doubled Nd: YAG line. Since FSDHI enables us to precisely measure vibration amplitudes over the whole inspected area with very high lateral resolution, it could also be a very useful tool for measurement of vibration amplitudes and mode structures for research in the field of adaptive suppression systems. Such a measurement would provide a necessary feedback about the system behavior.This was the reason why we put an effort
Keywords:
digital holography; vibration measurement; vibration suppression
Available at various institutes of the ASCR
Measurement of Vibration Mode Structure for Adaptive Vibration Suppression System by Digital Holography
Previously the frequency-shifted digital holographic interferometry (FSDHI) for measurement of vibration amplitudes in range of nanometers was introduced and verified by authors [1,2]. The method ...
Preparation of multiphase materials with spark plasma sintering
Mušálek, Radek; Dlabáček, Zdeněk; Vilémová, Monika; Pala, Zdeněk; Matějíček, Jiří; Chráska, Tomáš
2013 - English
Spark plasma sintering (SPS), also called Field Assisted Sintering Technique (FAST), represents a novel method of preparation of sintered materials from powders. The main advantage of the SPS method is a high achievable heat rate (>200 °C/min) and high sintering temperatures (up to 2200 °C in our laboratory). Combination of high heating rate, rather high pressures (up to 80 MPa) and electric field fluctuations leads to an effective sintering and significant reduction of sintering time for both coarse-grained and nanocrystalline powders. Composite materials may be easily obtained by mixing or layering of different powders. The paper will introduce several examples of multiphase materials sintered by SPS at our institute and the establishment of procedures for routine testing of sub-sized specimens.
Keywords:
spark plasma sintering; powder metallurgy; composites; multiphase materials; FeAl matrix
Available at various institutes of the ASCR
Preparation of multiphase materials with spark plasma sintering
Spark plasma sintering (SPS), also called Field Assisted Sintering Technique (FAST), represents a novel method of preparation of sintered materials from powders. The main advantage of the SPS method ...
Korekce optických vad astronomických zrcadel
Rail, Zdeněk; Jareš, Daniel; Tomka, David; Doleček, Roman
2012 - Czech
Velká a světelná astronomická zrcadla vykazují značné mimoosové vady. Aby je bylo možné použít pro fotografování oblohy, je nutné použít ke korekci jejich vad korektory. S nimi je možné dosáhnout radikálního zlepšení obrazů hvězd na rovinném poli o velkém úhlovém průměru a v širokém spektrálním oboru. Korektory jsou napočítány jak pro zrcadla o sférickém, paraboloidickém i hyperboloidickém tvaru. Korekce vad je předvedana jak pro sférické,tak pro paraboloidickéi hzperboloidické zrcadlo. The paper deals with optical designs of correctors of large and fast spherical and aspherical mirrors. Optical aberrations can be corrected by means both lens and aspherical plates correcting systems. These subaperture systems are placed near focus of main mirror.
Keywords:
Astronomical Mirrors; correcting systems
Available at various institutes of the ASCR
Korekce optických vad astronomických zrcadel
Velká a světelná astronomická zrcadla vykazují značné mimoosové vady. Aby je bylo možné použít pro fotografování oblohy, je nutné použít ke korekci jejich vad korektory. S nimi je možné dosáhnout ...
Development of large aperture elements for active and adaptive optics
Kmetík, Viliam; Nemcová, S.; Jiran, L.; Stranakova, E.; Inneman, A.
2012 - English
Large-aperture elements for laser active and adaptive optics are investigated in collaboration within IOP AcSci CR, FEng CTU and 5M. A bimorph deformable mirror for high-power lasers based on a lightweight structure with a composite core is currently in development. In order to realize a sufficiently large working aperture we are using new technologies for production of core, bimorph actuator and DM reflector. Detailed simulation of components and structure is validated by measurement and testing. A research of DM actuation and response of a complicated mirror structure needed for an accurate control of a deformation is performed. Testing of samples and subscale measurements are currently performed, measurement of a complete structureis in preparation
Keywords:
laser active and adaptive optics
Available at various institutes of the ASCR
Development of large aperture elements for active and adaptive optics
Large-aperture elements for laser active and adaptive optics are investigated in collaboration within IOP AcSci CR, FEng CTU and 5M. A bimorph deformable mirror for high-power lasers based on a ...
Photonometers for coating and sputtering machines
Oupický, Pavel; Jareš, Daniel; Václavík, Jan; Vápenka, David
2012 - English
The concept of photonometers (alternative name of optical monitor of a vacuum deposition process)for coating and sputtering machines is based on photonometers produced by companies like SATIS or HV Dresden. Photometers were developed in the TOPTEC centre and its predecessor VOD (Optical Development Workshop of Institut of Plasma Physics AS CR) for more than 10 years. The article describes current status of the technology and ideas which will be incorporated in next development steps. Hardware and software used on coating machines B63D, VNA600 and sputtering machine UPM810 is presented.
Keywords:
photonometers
Available at various institutes of the ASCR
Photonometers for coating and sputtering machines
The concept of photonometers (alternative name of optical monitor of a vacuum deposition process)for coating and sputtering machines is based on photonometers produced by companies like SATIS or HV ...
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