Federal University of Roraima

About: Federal University of Roraima is a based out in . It is known for research contribution in the topics: Population & Thermogravimetry. The organization has 981 authors who have published 1218 publications receiving 7849 citations. The organization is also known as: Federal University of Roraima.

Guianodendron, a New Genus of Leguminosae (Papilionoideae) from South America

Abstract: The new genus Guianodendron Schutz Rodrigues & A. M. G. Azevedo (Leguminosae, Papilionoideae, Sophoreae) from Guyana and the Brazilian state of Amazonas is described and illustrated, and a new combination, Guianodendron praeclarum (Sandwith) Schutz Rodrigues & A. M. G. Azevedo, is made. The genus is characterized by a radial corolla with auriculate petals; five stamens; reduced ovule number; a straight hypanthium; indehiscent, flattened, and sutural-winged fruits; persistent bracts and bracteoles; leaflets with a papillate abaxial epidermis; and ovate to ovate-elliptic markedly striate stipules.

Invasão por espécies arbóreas exóticas em remanescentes florestais no Planalto Sul Catarinense

Abstract: Este estudo objetivou avaliar a invasao por especies arboreas exoticas em dois fragmentos (F1 e F2) de Floresta Ombrofila Mista (FOM) em Lages, SC. Foram alocadas 25 parcelas por fragmento, distribuidas em cinco transecoes de 20 x 100 m, perpendiculares as bordas e com distância de 100 m entre si, onde foram avaliados os individuos dos estratos adulto (DAP - diâmetro a altura do peito > 5 cm) e regenerante (DAP 10 cm). Esses foram identificados e mensurados (circunferencia e altura). Foi calculado, para as especies de cada estrato e de cada fragmento, o Indice de Invasao Biologica (IIB). A relacao entre o IIB e a distância da borda foi verificada por meio de regressoes lineares simples. O agrupamento de especies exoticas e nativas foi determinado por meio de correlacoes de Spearman e de dendrogramas. Foram amostrados 3.701 individuos distribuidos em 105 especies, sendo cinco especies invasoras. No F1 houve valores de IIB relativamente baixos (0,05 e 0,54), com Pinus taeda L., obtendo-se a maior participacao na invasao, e esse esteve agrupado com especies nativas pioneiras. Os IIB´s no F2 foram altos (0,61 e 1,96), principalmente pela elevada participacao de Ligustrum lucidum W.T. Aiton., que ficou agrupado a especies tipicas da FOM. Nao foi observada relacao entre a distância da borda e a intensidade da invasao biologica. Os resultados indicaram que os fragmentos apresentaram diferentes padroes de invasao biologica, determinados pela natureza da matriz de entorno e pelas caracteristicas ecologicas das especies invasoras.

Spherical Particles of Zirconia–Titania of Hexagonal Structure from a Neutral Amine Route

Abstract: Through the sol–gel process, using the so-called neutral amine route, spherical particles of 1:1 zirconia–titania were synthesized from zirconium(IV) and titanium(IV) butoxides as well as 1,12-diaminododecane as precursor species. The obtained product exhibited a hexagonal structure, as determinated by X-ray diffraction data. The obtained material was also characterized by thermogravimetry, differential scanning calorimetry, infrared spectroscopy, scanning electron microscopy, and surface area measurements. Despite the release of template molecules on heating, the spherical morphology was retained up to about 1200°C, at which the disruption of the spheres took place.

Produção e atributos de qualidade de cultivares de macieira nas condições subtropicais da região Leste paulista

Abstract: These research aimed evaluate the production and quality attributes of apple tree cultivars in subtropical conditions at eastern of Sao Paulo state. For such, an assay of competition among cultivars was implanted in the Jundiai city, SP, with seven cultivars ('Eva', 'Condessa', 'Princesa', 'Rainha', 'Imperial Gala', 'Daiane', and 'Baronesa'). The experiment was implanted in 2006, the spacing was 3,0mx1,5m, and the plants were grafting in Marubakaido roostock and M9 inter-grafting. The evaluations had been carried through in two production cycle (2008/09 and 2009/10), the phenological stage, productive aspects and fruit quality attributes were evaluated. 'Eva', 'Baronesa' and 'Princesa' showed higher productive performance. The 'Baronesa' apple presented fruit quality attributes most suitable for the fresh market, i.e., lower acidity and good firmness, and the highest ratio.

Morfologia de plântulas de cinco leguminosas genistóides arbóreas do Brasil (Leguminosae-Papilionoideae)

Abstract: This work aims to describe, illustrate and compare the seedling morphology of five tree species of the genera Bowdichia, Cyclolobium, Diplotropis, Ormosia, and Poecilanthe, which belong to the genistoid clade (Leguminosae Papilionoideae). Phanero-epigeal-foliaceous seedlings are found in Bowdichia virgilioides Kunth, Cyclolobium brasiliense Benth. has phanero-epigeal-reserve seedlings, while Ormosia arborea (Vell.) Harms, Diplotropis martiusii Benth., and Poecilanthe parviflora Benth. possess crypto-hypogeal-reserve seedlings. Some other relevant seedling morphological characters are discussed and compared with those of previously studied species in these genera.