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Optické čerpání atomů rubidia pomocí Ti:Sa laseru
Buchta, Z. ; Rychnovský, J. ; Bartušek, Karel ; Lazar, Josef
The rapidly growing interest in production of hyperpolarized noble gasses (HpG), predominantly 3He and l29Xe for Nuclear Magnetic Resonance (NMR) experiments is driven by potentially attractive medical applications. Neither helium nor xenon is normally present in the body, so the experiments do not suffer from unwanted background signals. Among the potential medicine applications, the opportunity to image organs with low water content and/or with air spaces, such as colon or lungs, has raised a considerable interest. Current conventional imaging techniques cannot provide good images of these hollow spaces. These applications show that HpG may become a useful tool for non-invasive investigation of human lung ventilation, giving access to static imaging during breathhold, dynamics of inspiration/expiration, and functional imaging. This paper describe the way of optical pumping of Rb vapour by Ti:Sa laser which is necessary for attainment hyperpolarized state of 129Xe
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Všudypřítomné exponenciální zobrazení a edukační aspekty interdisciplinární fyziky
Gottvald, Aleš
We emphasize the concept of exponential family and elucidate its ubiquitous and unifying role for interdisciplinary physics. We outline some metamorphoses of the exponential family in Bayesian Inference, Statistical Thermodynamics, Quantum Physics, Fourier Spectroscopy, Analytical Combinatorics, Sufficient Statistics, Symmetries and Lie Groups, Complex Systems (spiral geometries, power laws, phyllotaxis). On a heuristic level, the exponential family elucidates analogies between many seemingly scattered concepts and constructions, thus representing a tool of remarkable educational value. On a deeper epistemic level, the exponential faimly points out to some important ideas behind information physics and interdisciplinary science in general, thus representing a vivid research concept
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Zobecněné entropie: módní omyl nebo nový vhled do fyziky?
Gottvald, Aleš
We reconsider major arguments which have been suggested for justifying role of "generalized entropies" in "nonextensive statistical thermodynamics" by Tsallis et al. Our analysis shows that the crucial arguments advocating some fundamental need for these "generalized entropies" are incorrect. Consequently, rather than bringing some principally new physical insight, the "generalized entropies" and "nonextensive statistical thermodynamics" represent some conceptually misleading views on the Maximum Entropy Principle and probability theory itself
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