Atomic Frequency Standard
Mostrando 13-17 de 17 artigos, teses e dissertações.
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13. Relógio atômico a feixe efusivo de 133Cs: estudo da estabilidade e da acuracia como função do deslocamento da frequência atômica devido ao efeito zeeman de segunda ordem, ao cavity pulling e ao rabi pulling / A 133Cs Atomic Beam Clock: study of its accuracy and stability as a function of the atomic frequency shift due to the second order zeeman effect, the cavity pulling and the rabi pulling
Since 1967, the definition of the second is based on the atomic properties of the 133Cs atom. The device that realises this definition is an atomic clock. In this work, we present the progress made in the last year on Brazilian scientific time and frequency program. The aim of this dissertation work is the caracterization of our standard. We report the major
Publicado em: 2003
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14. Determinação de bismuto por absorção atomica com geração de hidreto (BiH3) em um sistema de injeção em fluxo
Quality control of industrial products leads to continuous development and improvement of new chemical analytical methods. The presence of elements at trace levels requires instrumental methods which in turn can be automated. Trace amounts of bismuth can be found in clinical, metallurgical and environmental samples. Each matrix requires an efficient and fast
Publicado em: 1991
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15. The 31S0-33P0 transition in the aluminum isotope ion 26A1+: a potentially superior passive laser frequency standard and spectrum analyzer.
The aluminum 26 isotope ion is proposed here as a possible candidate for a superior atomic clock. For this even isotope, the extraordinarily long lifetime of the 33P0 state offers a potential clock transition (31S0-33P0) linewidth of 300 microHz. The mF = 0 --> 0 transition has only a quadratic Zeeman shift approximately 4 x 10(-18) at 0.1 Gauss magnetic fie
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16. Standard atomic volumes in double-stranded DNA and packing in protein–DNA interfaces
Standard volumes for atoms in double-stranded B-DNA are derived using high resolution crystal structures from the Nucleic Acid Database (NDB) and compared with corresponding values derived from crystal structures of small organic compounds in the Cambridge Structural Database (CSD). Two different methods are used to compute these volumes: the classical
Oxford University Press.
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17. On the use of low-frequency normal modes to enforce collective movements in refining macromolecular structural models
As more and more structures of macromolecular complexes get solved in different conditions, it has become apparent that flexibility is an inherent part of their biological function. Normal mode analysis using simplified models of proteins such as the elastic network model has proved very effective in showing that many of the structural transitions derived fr
National Academy of Sciences.