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A study of binary stars with accretion disks
Chadima, Pavel ; Harmanec, Petr (advisor) ; Krtička, Jiří (referee) ; Mourard, Denis (referee)
This thesis contains spectroscopic analyses of two unusual binaries with circum- stellar disks - β Lyr and ǫ Aur. Several hundred optical spectra were processed and analyzed for both binaries which led to several original findings. For β Lyr, it was a discovery of a weak shell spectrum originating in a disk pseudophotosphere and a hidden satellite spectrum, present only during eclipses, which arise from additional absorption of the primary light passing through the gaseous envelope around the secondary. For ǫ Aur, it led to the discovery of the apparent multiperiodic line vari- ability occuring during the current eclipse with a dominant and common period of 66d .21 and to an explanation of complex Hα line profiles during the eclipse which is again caused by an additional absorption of a primary light in an atmosphere of a dark disk around a secondary. Also rich series of radial velocity measurements and photometric observations were collected and used to determine a new precise orbital solution for ǫ Aur. Further, a hydrodynamical and a radiative modeling of a discontinuous mass transfer in a close binary system was carried out which resulted in a formation of an elongated disk with a slow prograde revolution, demonstrated itself by double emission Hα line profiles that exhibit V/R variations.
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Low-coherence interferometry in industrial metrology
Buchta, Zdeněk
The paper describes an experimental arrangement for optical pumping of rubidium based on a high-power laser diode and high power lased diode array. The emission spectrum of the laser diode array was narrowed by external injection locking technique by means of cw Ti:Sa resp. an extended cavity laser (ECL) based on a high-power laser diode. The laser system was designed to be a crucial part of the HpXe (hyperpolarized xenon) production process.
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Kontrast dopantu – otázka pro elektronovou mikroskopii
Frank, Luděk
Results obtained when imaging doped areas in silicon by means of various electron microscopical methods are reviewed. These include secondary electron imaging in the conventional SEM and SEM equipped with the cathode lens, imaging with very slow backscattered electrons by means of the cathode lens, and imaging in a photoelectron emission microscope. It is suggested that important role in the contrast formation plays local differences in the absorption of excited hot electrons on their trajectories toward surface.
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Myocardial perfusion scintigraphy in the diagnosis of Ischemic Heart Disease
VŠOLKOVÁ, Marta
Abstract Radionuclide examination of coronary arteries - myocardial perfusion scintigraphy using a method of a single-photon emission computed tomography ( SPECT ) - provides by a non-invasive way functional information which is complementary to morphologic information gained by an invasive selective coronary angiography. However, the examination of cardiac arteries in the diagnostics of ischemic heart disease (IHD) is carried out by means of other examination procedures which are together in a mutual interaction. Therefore, apart from the basic anatomy and physiology of the coronary arteries and pathophysiology of IHD, the section of the theoretical part of the work also provides an overview of examination methods which are in relation to the radiology assistant´s work. The methods used to diagnose IHD are divided into non-invasive stress tests and invasive diagnostic and therapeutic methods. Among the non-invasive stress tests are: ergometer stress test, ECG Holter monitoring, echocardiography examination, stress cardiac mag-netic resonance imaging, myocardial perfusion scintigraphy, 18F-FDG PET, CT angi-ography, CT determination of calcium score, and optical coherence tomography. The category of invasive diagnostic and therapeutic method includes: selective coronary angi-ography, PTCA, and CABG. Detailed description of SPECT myocardial perfusion scin-tigraphy is described in a separate chapter. Objective of the practical part of the work was to compare the conclusions of SPECT myocardial perfusion scintigraphy results with the conclusions of coronary angiography results. I looked for answers to the two following research issues: 1.Would the conclusions of myocardial perfusion scintigraphy examination medical report differ from the conclusions of coronary angiography medical report maximally by 10%? 2. Would be the non-corresponding results different in men and women? Methodology: In the medical files of patients who were recommended for coronary an-giography after myocardial scintigraphy I looked up the final medical reports on their coronary angiography findings. The patients with negative scintigraphy findings who underwent shortly after myocardial scinfigraphy selective coronary angiography with positive results were also included into the group. Group of patients: From January 2013 to September 2013 a group of patients underwent stress myocardial scintigraphy examination at the CNM in Prague. In total there were 619 patients - 344 men and 275 women. 187 patients underwent an additional rest myocardial perfusion scintigraphy. There were positive findings in 86 of these patients with referral for coronary angiography. Backward search proved impossible to find coronary angi-ography results in 19 patients. Nevertheless, 3 patients with false-negative scintigraphy findings were included into the group. The resulting group thus consists of 70 patients 23 women and 47 men. Results: The results of SPECT myocardial perfusion scintigraphy and coronary angi-ography differ in 13% which slightly exceeds the limit of 10% set in the research issue. Two thirds of non-corresponding scintigraphy results were false-positive, one third false-negative. With regards to the second research issue I came to the conclusion that in the detection of IHD the number of non-corresponding result of SPECT myocardial scintigraphy and cor-onary angiography is identical in both genders. There was 13 % of non-corresponding findings in women and 12.7 % of non-corresponding findings in men.
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Autoemisní katody pro elektronové mikroskopy
Delong, Armin ; Kolařík, V.
Field emission emitters have significantly improved the coherence of electron guns in electron microscopes and allowed to reach atomic-scale resolution in the case of crystal imaging. Even now, thirty years after the first application of field emission emitters, one can hardly say that the development of electron emitters has been finalized
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Deposition of functional thin films by plasma processes
SEZEMSKÝ, Petr
An aim of this work is a research of a deposition process of indium tin oxide by plasma assisted methods. The thesis deals with plasma diagnostics, e.g. Langmuir probe diagnostics and optical emission spectroscopy, as well as describes experiments of film deposition including their diagnostics, e.g. absorption spectroscopy, X-ray diffractometry and atomic force microscopy.
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