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Classification of distances in cosmology
Křížek, Michal; Mészáros, A.
2018 - English
In cosmology many different distances are defined: angular, comoving, Euclidean, Hubble, light-year, luminosity, Minkowski, parallax, proper motion, redshift, ... distance. There is not one single natural distance, since the universe is expanding, curved, and we look back in time. In this survey paper we will concentrate on geometrical interpretations of the above-mentioned distances. Keywords: standard cosmological model; cosmological principle; Friedmann equation; cosmological parameters; Einstein static universe Available in digital repository of the ASCR
Classification of distances in cosmology

In cosmology many different distances are defined: angular, comoving, Euclidean, Hubble, light-year, luminosity, Minkowski, parallax, proper motion, redshift, ... distance. There is not one single ...

Křížek, Michal; Mészáros, A.
Matematický ústav, 2018

Synergické efekty svařování laser - TIG
Kubíček, J.; Doležal, P.; Mrňa, Libor; Šebestová, Hana; Horník, Petr
2018 - Czech
Laserové svařování ve srovnání s konvenčními obloukovými metodami je doprovázeno rychlou rychlostí chlazení. To může vést ke vzniku nežádoucí mikrostruktury svařovaného kovu a tepelně postižené zóny některých ocelových tříd, což má negativní dopad na jejich mechanické vlastnosti. Předehřívání je poměrně problematické kvůli vysoké rychlosti svařování laserem. Byla testována možnost předehřívání teplem z obloukového výboje přidruženého hořáku TIG. Přesný držák byl vyroben pro upevnění hořáku na laserovou svařovací hlavu, umožňující umístění TIG elektrody směrem k laserovému paprsku a obrobku. Byla provedena řada ocelových zkoušek S460MC a S700MC s vysokou pevností. Účinek proudění TIG na mikrostrukturální změny byl prokázán. Některé svařovací experimenty byly porovnány s simulacemi svařování SYSWELD. Laser welding compared to conventional arc methods is accompanied by rapid cooling rates. It can lead to the formation of undesirable microstructure of the weld metal and heat affected zone of some steel grades which has a negative impact on their mechanical properties. The preheating is quite problematic because of high speed of laser welding. The possibility of preheating by the heat of the arc discharge of the associated TIG burner has been tested. Precise holder has been fabricated to fix the burner to the laser welding head allowing TIG electrode positioning towards the laser beam and the workpiece. A number of high strength steel S460MC and S700MC welding experiments was performed. The effect of TIG current on microstructural changes has been proven. Some welding experiments were compared to the SYSWELD welding simulations.\n Keywords: laser – TIG welding; cooling rate; HSLA steels; microstructure; tensile strength Available at various institutes of the ASCR
Synergické efekty svařování laser - TIG

Laserové svařování ve srovnání s konvenčními obloukovými metodami je doprovázeno rychlou rychlostí chlazení. To může vést ke vzniku nežádoucí mikrostruktury svařovaného kovu a tepelně postižené zóny ...

Kubíček, J.; Doležal, P.; Mrňa, Libor; Šebestová, Hana; Horník, Petr
Ústav přístrojové techniky, 2018

Optimization of photochemical vapor generation of molybdenum as a sample introduction for ICP-MS
Šoukal, Jakub; Musil, Stanislav
2018 - English
Conditions of photochemical vapor generation of molybdenum with ICP-MS detection have been in detail investigated. Keywords: ICP-MS; molybdenum; photochemical vapor generation Available at various institutes of the ASCR
Optimization of photochemical vapor generation of molybdenum as a sample introduction for ICP-MS

Conditions of photochemical vapor generation of molybdenum with ICP-MS detection have been in detail investigated.

Šoukal, Jakub; Musil, Stanislav
Ústav analytické chemie, 2018

Sebezařazení na levopravé škále politické orientace – červen 2018
Červenka, Jan
2018 - Czech
V rámci červnového šetření Centrum pro výzkum veřejného mínění Sociologického ústavu AV ČR, v.v.i., položilo všem respondentům otázku, která na jedenáctibodové škále s body 1 až 5 reprezentujícími levou část spektra, s bodem 6 představujícím střed a body 7 až 11 zastupujícím pravou stranu, sleduje levopravou politickou orientaci: „V politice lidé někdy hovoří o pravici a levici. Kam byste se sám zařadil na této stupnici?“ In the June survey the Public Opinion Research Centre gave all respondents a question that at eleven-point scale measures the left-right political orientation: "In politics, people sometimes talk about right and left. Where would you place yourself ranked on this scale?" Keywords: left-right; political orientation Fulltext is available at external website.
Sebezařazení na levopravé škále politické orientace – červen 2018

V rámci červnového šetření Centrum pro výzkum veřejného mínění Sociologického ústavu AV ČR, v.v.i., položilo všem respondentům otázku, která na jedenáctibodové škále s body 1 až 5 reprezentujícími ...

Červenka, Jan
Sociologický ústav, 2018

Francis Dvorník - Scholar and His Work. Papers read at the international symposium held on the occasion of the 40th anniversary of his demise.
Vavřínek, Vladimír; Melichar, Petra; Čechová, Martina
2018 - English
The volume contains the presentations from the international conference Francis Dvorník - Scholar and His Work and the last unfinished work of the scholar, The Conflict between Sacerdotium and Imperium in the Middle Ages. East and West. Keywords: Dvorník, Francis; life; work Available at various institutes of the ASCR
Francis Dvorník - Scholar and His Work. Papers read at the international symposium held on the occasion of the 40th anniversary of his demise.

The volume contains the presentations from the international conference Francis Dvorník - Scholar and His Work and the last unfinished work of the scholar, The Conflict between Sacerdotium and ...

Vavřínek, Vladimír; Melichar, Petra; Čechová, Martina
Slovanský ústav, 2018

Recent Trends in Charged Particle Optics and\nSurface Physics Instrumentation. Proceedings\nof the 16th International Seminar
Mika, Filip; Pokorná, Zuzana
2018 - English
Available at various institutes of the ASCR
Recent Trends in Charged Particle Optics and\nSurface Physics Instrumentation. Proceedings\nof the 16th International Seminar

Mika, Filip; Pokorná, Zuzana
Ústav přístrojové techniky, 2018

Very low energy electron transmission spectromicroscopy
Daniel, Benjamin; Radlička, Tomáš; Piňos, Jakub; Mikmeková, Šárka; Konvalina, Ivo; Frank, Luděk; Müllerová, Ilona
2018 - English
For more than 25 years, Scanning Low Energy Electron Microscopy (SLEEM) has been\ndeveloped at the Institute of Scientific Instruments (ISI), with several commercially available SEMs adapted with a cathode lens for SLEEM use, as well as a dedicated self-built UHV\nSLEEM setup.\nFor a better understanding of contrast formation at low energies, especially at very low\nenergies below 50 eV, where the local density of states plays an important role, more general\nknowledge about the interaction of (very) low energy electrons with solids is required. This\nwill be achieved using a newly developed ultra-high vacuum (UHV SLEEM) setup which\nincludes several enhancements compared to other available machines. Data processing is\npresented in, and processed data will be further used and tested with the Monte Carlo\nsimulation package BRUCE, which is being developed by Werner et al. at TU Vienna. Available at various institutes of the ASCR
Very low energy electron transmission spectromicroscopy

For more than 25 years, Scanning Low Energy Electron Microscopy (SLEEM) has been\ndeveloped at the Institute of Scientific Instruments (ISI), with several commercially available SEMs adapted with a ...

Daniel, Benjamin; Radlička, Tomáš; Piňos, Jakub; Mikmeková, Šárka; Konvalina, Ivo; Frank, Luděk; Müllerová, Ilona
Ústav přístrojové techniky, 2018

Hiding e-beam exposure fields by deterministic 2D pattering
Horáček, Miroslav; Knápek, Alexandr; Matějka, Milan; Krátký, Stanislav; Urbánek, M.; Mika, Filip; Kolařík, Vladimír
2018 - English
The high stability and good current homogeneity in the spot of the e-beam writer is crucial to\nthe exposure quality, particularly in the case of large-area structures when gray-scale\nlithography is used. Even though the deflection field distortion is calibrated regularly and\nbeam focus and beam astigmatism is dynamically corrected over the entire deflection field, we can observe disturbances in the exposed relief.\nRecently, we presented a method that makes use of e–beam exposure imperfection by\nintroducing marginally visible high–frequency diffraction gratings of variable pitch that fill in\nseparate orthogonal exposure fields. The actually presented approach follows up our\nresearch on aperiodic arrangements of optical primitives, especially on the phyllotactic–\nlike arrangement of sub–micron relief optical elements. This approach is extended from the\ndiffraction element arrangement to the higher level of exposure fields arrangements. Keywords: phyllotaxis; electron beam lithography Available at various institutes of the ASCR
Hiding e-beam exposure fields by deterministic 2D pattering

The high stability and good current homogeneity in the spot of the e-beam writer is crucial to\nthe exposure quality, particularly in the case of large-area structures when gray-scale\nlithography is ...

Horáček, Miroslav; Knápek, Alexandr; Matějka, Milan; Krátký, Stanislav; Urbánek, M.; Mika, Filip; Kolařík, Vladimír
Ústav přístrojové techniky, 2018

STEM modes in SEM
Konvalina, Ivo; Paták, Aleš; Mikmeková, Eliška; Mika, Filip; Müllerová, Ilona
2018 - English
The segmented semiconductor STEM detector in the Magellan 400 FEG SEM microscope\n(https://www.fei.com/) is used to detect transmitted electrons (TEs) and allows observing\nsamples in four imaging modes. Two modes of objective lens, namely high resolution (HR)\nand ultra-high resolution (UHR), differ by their resolution and by the presence or absence of\na magnetic field around the sample. If the beam deceleration (BD) mode is chosen, then\nan electrostatic field around the sample is added and two further microscope modes HR + BD\nand UHR + BD, become available. Trajectories of TEs are studied with regard to their angular\nand energy distribution in each mode in this work.\n Available at various institutes of the ASCR
STEM modes in SEM

The segmented semiconductor STEM detector in the Magellan 400 FEG SEM microscope\n(https://www.fei.com/) is used to detect transmitted electrons (TEs) and allows observing\nsamples in four imaging ...

Konvalina, Ivo; Paták, Aleš; Mikmeková, Eliška; Mika, Filip; Müllerová, Ilona
Ústav přístrojové techniky, 2018

Creation of electron vortex beams using the holographic reconstruction method in a scanning electron microscope
Řiháček, Tomáš; Horák, M.; Schachinger, T.; Matějka, Milan; Mika, Filip; Müllerová, Ilona
2018 - English
Electron vortex beams (EVB) were theoretically predicted in 2007 and first experimentally\ncreated in 2010. Although they attracted attention of many researchers, their\ninvestigation takes place almost solely in connection with transmission electron microscopes (TEM). On the other hand, although scanning electron microscopes (SEM) may provide some advantages for EVB applications, only little attention has been dedicated to them. Therefore, the aim of this work is to create electron vortices in SEM at energies of several keV. Available at various institutes of the ASCR
Creation of electron vortex beams using the holographic reconstruction method in a scanning electron microscope

Electron vortex beams (EVB) were theoretically predicted in 2007 and first experimentally\ncreated in 2010. Although they attracted attention of many researchers, their\ninvestigation takes place ...

Řiháček, Tomáš; Horák, M.; Schachinger, T.; Matějka, Milan; Mika, Filip; Müllerová, Ilona
Ústav přístrojové techniky, 2018

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