17,505 research outputs found

    Mathematical modelling of straw bale combustion in cigar burners

    Get PDF

    Solar Irradiance Observed from PVO and Inferred Solar Rotation

    Get PDF
    Solar irradiance in the extreme ultraviolet flux (EUV) has been monitored for 11 years by the Pioneer Venus Orbiter (PVO). Since the experiment moves around the Sun with the orbital rate of Venus rather than that of Earth, the measurement gives us a second viewing location from which to begin unravelling which irradiance variations are intrinsic to the Sun, and which are merely rotational modulations whose periods depend on the motion of the observer. Researchers confirm an earlier detection, made with only 8.6 years of data, that the EUV irradiance is modulated by rotation rates of two families of global oscillation modes. One family is assumed to be r-modes occupying the convective envelope and sharing its rotation, while the other family (g-modes) lies in the radiative interior which as a slower rotation. Measured power in r-modes of low angular harmonic number indicates that the Sun's envelope rotated about 0.7 percent faster near the last solar maximum (1979 thru 1982) than it did during the next rise to maximum (1986 to 1989). No change was seen in the g-mode family of lines, as would be expected from the much greater rotational inertia of the radiative interior

    Apicultura sustentável na propriedade familiar de base ecológica.

    Get PDF
    bitstream/item/30823/1/Circular-64.pdfMerta: 2008

    Alimentação artificial estimulante em apicultura sustentável.

    Get PDF
    bitstream/item/44096/1/folder-alimentacao-artificial.pd

    Captura de enxames em vôo ou recém-pousados para apicultura sustentável.

    Get PDF
    bitstream/item/44187/1/CAPTURA-DE-ENXAME.pd

    Alimentação de enxames em apicultura sustentável

    Get PDF
    bitstream/item/30822/1/Circular-63.pdfMeta: 2008

    Localização ideal para o apiário em agricultura familiar.

    Get PDF
    bitstream/CPACT-2010/13002/1/apiario-agricultura.pd

    A Search for r-Modes from 1825 to the Present

    Get PDF
    Global oscillations (r-modes) of the Sun's outer convective envelope with periods approximately 1 month and longer have been detected in several short data strings of several years duration. To test whether r-modes might persist beyond one 11 year cycle, the daily sunspot numbers from 1825 to the present were analyzed. Good evidence, but confidence level less than 3sigma, was found for most of the 14 r-modes with spherical harmonic index lambda less than or equal to 5 that can exist in the presence of solar differential rotation. The characteristic rotation rate of almost every such r-mode was detected, displaced systematically from its expected value by only 0.15%. If this probable detection is real, then most low harmonic r-modes have lifetimes exceeding one century and the rotation of the Sun's outer layers varies by less than 0.05%, except possibly at solar minimum
    corecore