The Serra de Itabaiana National Park, Sergipe, is situated in a transition area between Atlantic Forest and the Caatinga and is considered by the Ministério do Meio Ambiente to be extremely important for the conservation of the Atlantic Forest flora. The paucity of floristic information from Sergipe state and areas of ecological tension motivated this floristic survey in the only National Park in the state. Botanical collections were made from 2006 to 2009, in six expedictions, by means of random walking. A total of 552 species distributed in 99 families of angiosperms and one gymnosperm were found. Of the species collected, 187 occurred in shrubby-herbaceous, 304 in shrubby, and 247 in arborescent physiognomy, with 23 common to all physiognomies. Leguminosae (41 spp.), Cyperaceae (40 spp.), Poaceae (38 spp.), Orchidaceae (30 spp.), Euphorbiaceae (27 spp.), Rubiaceae (24 spp.), Melastomataceae (21 spp.) and Bromeliaceae (20 spp.) were the richest families. The study revealed the presence of species in common with the Caatinga, Cerrado, Seasonal Forest, campo rupestre, restinga, tabuleiro and areas of ecological tension, corroborating floristically the classification of the locality as an area of ecological tension and reasserting its importance for the conservation of biodiversity.

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We report room-temperature transversal magnetoimpedance (TMI) and Hall-effect measurements performed in ribbons of the zero-magnetostriction soft-ferromagnet Co70.4Fe4.6Si15B10 alloy annealed at 587 K for 15 min at a dc magnetic field of 2 kOe. The annealing showed little effect on the magnetostriction of the samples. The frequency f and the amplitude Iac of the current used in the measurements, and the measuring magnetic field H were varied in the intervals 10≤f≤105 Hz, 2.5≤Iac≤25 mA, and −15≤H≤15 kOe, respectively. The magnetic field dependence of the TMI shows a peak which is strongly dependent on f and on Iac. It reaches the giant value of 28% at H=350 Oe for f=100 kHz and Iac=25 mA. This TMI giant value is of the same order of the giant longitudinal magnetoimpedance (GLMI) but its peak is positioned in a magnetic field two orders of magnitude larger than the value obtained for the GLMI. The Hall effect yielded a value of RS=0.43 μΩ cm kOe−1. Peaks which are also frequency dependent were observed at the Hall voltage.

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Os resíduos agroindustriais, provenientes da cana-de-açúcar, são ofertados com grande disponibilidade e baixo custo e ainda são pouco aproveitados gerando passivo ambiental, constituindo assim intenso objeto de pesquisa. A complexa estrutura da parede celular da biomassa é, em geral, resistente à bioconversão, dificultando o fornecimento dos carboidratos necessários para obtenção de combustíveis e produtos químicos. É então necessária a realização de uma etapa prévia denominada pré-tratamento, que tem como objetivo alterar ou remover a lignina e a hemicelulose, aumentar a área superficial e diminuir o grau de polimerização e cristalinidade da celulose. O presente trabalho teve como objetivo valorizar a palha de cana-de-açúcar através do estudo da etapa de pré-tratamento com ácido sulfúrico diluído, avaliando-se os seguintes parâmetros operacionais: temperatura, tempo de reação, carga de sólidos e concentração de ácido, para obter um hidrolisado rico em xilose.