11,189 research outputs found
Mirror-assisted coherent backscattering from the Mollow sidebands
In front of a mirror, the radiation of weakly driven large disordered clouds
presents an interference fringe in the backward direction, on top of an
incoherent background. Although strongly driven atoms usually present little
coherent scattering, we here show that the mirror-assisted version can produce
high contrast fringes, for arbitrarily high saturation parameters. The contrast
of the fringes oscillates with the Rabi frequency of the atomic transition and
the distance between the mirror and the atoms, due to the coherent interference
between the carrier and the Mollow sidebands of the saturated resonant
fluorescence spectrum emitted by the atoms. The setup thus represents a
powerful platform to study the spectral properties of ensembles of correlated
scatterers
Utilização de resíduos de carvão vegetal associado a fontes orgânicas de nutrientes no manejo sustentável do solo e do guaranazeiro (Paullinia cupana var. sorbilis (Mart.) Ducke) na Amazônia Central.
Neste capítulo serão apresentados resultados iniciais de um experimento de longo prazo cujo objetivo é conhecer a influência de resíduos de carvão vegetal, esterco de galinha e farinha de osso nas propriedades químicas e físicas do solo, bem como na sustentabilidade da cultura do guaranazeiro
Caracterização de dois perfis com horizonte antrópico (Terra Preta de Índio) no Lago do Limão - AM.
O trabalho teve por objetivo caracterizar dois perfis com horizonte antrópico no Lago do Limão, município de Iranduba
Significant subsoil accumulation of mineral nitrogen under perennial crops in a ferralitic Amazonian upland soil: effects of land use systems and single-tree patterns.
bitstream/item/180979/1/ID-3848-38-57.pd
Estoque de carbono em Terra Preta do Índio no Município de Iranduba-AM.
O presente trabalho objetivou estimar o estoque de carbono até um metro de profundidade em uma área de TPI de aproximadamente seis hectares
Injection locking of a low cost high power laser diode at 461 nm
Stable laser sources at 461 nm are important for optical cooling of strontium
atoms. In most existing experiments this wavelength is obtained by frequency
doubling infrared lasers, since blue laser diodes either have low power or
large emission bandwidths. Here, we show that injecting less than 10 mW of
monomode laser radiation into a blue multimode 500 mW high power laser diode is
capable of slaving at least 50% of the power to the desired frequency. We
verify the emission bandwidth reduction by saturation spectroscopy on a
strontium gas cell and by direct beating of the slave with the master laser. We
also demonstrate that the laser can efficiently be used within the Zeeman
slower for optical cooling of a strontium atomic beam.Comment: 2nd corrected version (minor revisions); Manuscript accepted for
publication in Review of Scientific Instruments; 5 pages, 6 figure
The rain forest is a human creation.
The Amazon rain forest was, before the Europeans came, as cultivated as forests anywhere else in the world. It was not 'virgin'. The native people still living within the forest are remnants descended from highly structured societies with suitably developed agriculture and food systems. A vast number of foods including guaraná, açaí and manioc (above) have been cultivated for thousands of years. This revolutionises understanding of the nature and value of Amazonia, the imperative need to protect and strengthen its own identity, and to learn yet again that in agro-ecology is the salvation of the planet
Soil quality parameters of a xanthic ferralsol in the Amazon basin.
A Fertbio 2002 reuniu a XXV Reunião Brasileira de Fertilidade do Solo e Nutrição de Plantas, a IX Reunião Brasileira sobre Micorrizas, o VII Simpósio Brasileiro de Microbiologia do Solo e a Reunião Brasileira de Biologia do Solo, sob o tema: "Agricultura: bases ecológicas para o desenvolvimento social e econômico sustentado
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