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Search Results: 1 - 10 of 11317 matches for " Benedito Rocha;Frederico "
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Propriedades de chapas de aglomerado fabricadas com adesivo tanico de angico-vermelho (Anadenanthera peregrina) e uréia-formadeído
Carneiro, Angélica de Cássia Oliveira;Vital, Benedito Rocha;Frederico, Pedro Gustavo Ulisses;Carvalho, Ana Márcia M. Ladeira;Vidaurre, Graziela Baptista;
Revista árvore , 2009, DOI: 10.1590/S0100-67622009000300014
Abstract: the main objective of this work was to produce particleboards with hydrolysed "angico-vermelho" bark (anadenanthera peregrina) tannins as partial or total substitute of urea-formaldehyde. particleboards with the dimensions of 15.75" x 15.75" x 0.39" were manufactured with pinus elliottii particles and 8% of adhesive solids in relation to the dry mass of particles. adhesives employed either 100% urea-formaldehyde or 12.5, 25 and 37.5% of tannin adhesive. boards were also manufactured with pure tannin adhesives. the experimental design was constituted of five treatments and three repetitions. the particleboards average density was 0.7 g/cm3 (0.0618 oz/in3). board properties were determined according to the astm d-1037 (1993) standards. the mechanical propertiy values were compared to the minimum values established by the ansi/a 208.1 standards. water absorption and thickness swelling values were compared to the maximum values established by the din 68m761 (1) standards. the mechanical properties of boards produced with the adhesives containing tannins of "angico-vermelho", except for the elasticity module, exceeded the minimum values requested by the ansi/a1-280/93 standards. the water absorption and thickness swelling of all the boards exceeded the established maximum value after 2 and 24 h of immersion. it is ended that the adhesives of tannins of angico-vermelho can substitute partially or totally the commercial urea-formaldehyde adhesive and also that their mixtures are suitable for interior use, where resistance to humidity is not requested.
Efeito da hidrólise ácida dos taninos de Eucalyptus grandis w. hill ex Maiden nas propriedades dos adesivos tanicos
Carneiro, Angélica de Cássia Oliveira;Vital, Benedito Rocha;Frederico, Pedro Gustavo Ulisses;Santos, Rosimeire Cavalcante dos;Sousa Júnior, Wagner Patrício de;
Revista árvore , 2009, DOI: 10.1590/S0100-67622009000400016
Abstract: the objective of this research was to evaluate the effect of the acid hydrolysis of eucalyptus grandis w. hill ex maiden bark tannins on the properties of tannic adhesives. adhesives were synthesized with tannins hydrolyzed at four ph values, three reaction times and 10% of formaldehyde based on the tannin dry weight. ninety-six glued joints were prepared with eucalyptus grandis thin boards. shear resistance and wood failure percentage were determined according to the astm d 2339-93 standards. it was concluded that tannin hydrolysis decreased adhesive viscosity and increased the glue line shear resistance. however, it was observed a low percentage of wood failure.
Dinamica da concentra??o de mercado na indústria Brasileira, 1996-2003
Rocha, Frederico;
Economia e Sociedade , 2010, DOI: 10.1590/S0104-06182010000300003
Abstract: the aim of this paper is to study the changes in market concentration in the brazilian mining and manufacturing industries that took place from 1996 to 2003. the paper decomposes the herfindahl-hirschman index into variations in the size distribution and the number of firms. the results show that the average concentration did not change greatly in the period analyzed; however, a small group of industries showed significant differences in concentration. in these cases, changes in size distribution appear to have more importance than changes in the number of firms.
Produtividade do trabalho e mudan?a estrutural nas indústrias brasileiras extrativa e de transforma??o, 1970-2001
Rocha, Frederico;
Revista de Economia Política , 2007, DOI: 10.1590/S0101-31572007000200005
Abstract: using an indicator of labor productivity, this paper aims to assess the contribution of structural changes in the brazilian manufacturing and mining industries to productivity growth, during the 1970-2001 period. the conclusion is that: (i) there is no evidence to sustain that the brazilian industry has definitely reversed the productivity growth rates slowdown trend; (ii) there is no clear evidence of a positive influence of the structural bonus; and (iii) job creation seems to be concentrated in low productivity growth sectors.
Body size, female reproduction and sexual dimorphism in the lizard Ameiva ameiva (Teiidae) in a restinga of southeastern Brazil
Rocha, Carlos Frederico Duarte;
Revista Brasileira de Zoologia , 2008, DOI: 10.1590/S0101-81752008000200024
Abstract: in this study 57 specimens of the lizard ameiva ameiva (linnaeus, 1758) collected in the restinga at barra de maricá, in the state of rio de janeiro, southeastern brazil, were analyzed to investigate size relations and reproduction (in females) and sexual dimorphism of this population. we answered the following questions: 1) what is the minimum reproductive body size in females? 2) what is the average clutch size and 3) how is clutch size related to body size? 4) are body and head sizes sexually dimorphic? mean clutch size was 6.7 ± 2.1 eggs and was positively correlated with female body size. sexual dimorphism favoring males was found: adult mean snout-vent length was great in males (124.2 ± 17.8 mm) than females (96.5 ± 23.1 mm svl), and males were larger with respect to head width and length, and body mass. thus, despite the marked seasonality at barra de maricá, a. ameiva has an extended reproductive period. also, intrasexual selection may have acted on females to produce larger clutches, and on males, favoring larger males.
Reproductive ecology of the invader species gekkonid lizard Hemidactylus mabouia in an area of southeastern Brazil
Anjos, Luciano A.;Rocha, Carlos Frederico D.;
Iheringia. Série Zoologia , 2008, DOI: 10.1590/S0073-47212008000200006
Abstract: hemidactylus mabouia moreau de jonnés, 1818 is a "fixed" clutch size exotic species well established in brazil. in this paper we investigate some reproductive strategies adopted to minimize the costs of invariant clutch size to this invader species living in an environment with marked climatic seasonality in southeastern brazil (22°56?s; 46°55?w). the study was carried out from april 2002 to march 2003. females and males attain maturity at 47.9mm and 46.9mm svl, respectively. larger females tended to produce larger eggs. the reproduction occurred throughout the year, but only at the wet season the females increase the clutch frequency. there was a significant variation in mean testis volume among the months throughout the year and the largest means were recorded between august and december. maternal investment on egg size, increase on clutch frequency and seasonal increase on testis volume can represent important reproductive strategies of this invader species living in an non-urban habitat whit climatic seasonality (dry and cold weather season).
Host-ectoparasite specificity in a small mammal community in an area of Atlantic Rain Forest (Ilha Grande, State of Rio de Janeiro), Southeastern Brazil
Bittencourt, Emerson Brum;Rocha, Carlos Frederico Duarte;
Memórias do Instituto Oswaldo Cruz , 2003, DOI: 10.1590/S0074-02762003000600015
Abstract: the analyses of the ectoparasite species associated with a small mammal community on ilha grande, a coastal island in southern of the state of rio de janeiro, brazil, evaluated the level of host-ectoparasite specificity. was used the jaccard index for qualitative data to analyse the similarity. the lowest value of similarity occurred between proechimys iheringi and marmosops incanus and between sciurus aestuans and nectomys squamipes (cj = 0.08) and the highest between p. iheringi and oxymycterus sp. (cj = 0.33). this index showed a low value of similarity across the ectoparasite community. the only exception from this pattern of high host specificity occurred with p. iheringi and oxymycterus sp., which shared five species of ectoparasites. the similarity values, for most of the cases, is smaller than 0.2.
Ecology of Mabuya agilis (Raddi) (Lacertilia, Scincidae) at the restinga of Grumari, Rio de Janeiro, southeastern Brazil
Vrcibradic, Davor;Rocha, Carlos Frederico Duarte;
Revista Brasileira de Zoologia , 2002, DOI: 10.1590/S0101-81752002000600002
Abstract: some aspects of the ecology of the skink mabuya agilis (raddi, 1823) at the restinga habitat of grumari, in rio de janeiro, brazil are studied. most of the lizards were first sighted on the ground, though a few were using perches (mainly cacti) up to 30 cm high. mean body temperature in activity was 33.1 ± 2.4oc and was significantly correlated to air temperature. there was sexual dimorphism in size (snout-vent length - svl), with females growing larger than males. frequency of broken tails was high overall (83%) and did not differ between sexes. females and males are sexually mature at 49 mm and 47 mm svl, respectively. brood size averaged 3.2 ± 1.0 (range 1-5) and was positively and significantly related to female svl (r = 0.65, p = 0.001). relative clutch mass (rcm) of seven gravid females averaged 0.250 ± 0.042, being relatively low compared to those of other congeners. the diet of m. agilis was composed basically of arthropods, with relatively large and soft-bodied arthropods such as spiders, caterpillars and homopterans being the most important prey. the results of our work confirm and expand the knowledge of ecological tendencies previously observed for m. agilis in other areas.
Nematode assemblages of some insular and continental lizard hosts of the genus Mabuya Fitzinger (Reptilia, Scincidae) along the eastern Brazilian coast
Rocha, Carlos Frederico D.;Vrcibradic, Davor;
Revista Brasileira de Zoologia , 2003, DOI: 10.1590/S0101-81752003000400031
Abstract: nematode assemblages associated to three species of lizards of the genus mabuya fitzinger, 1826 [m. agilis (raddi, 1823), m. caissara rebou?as-spieker, 1974 and m. macrorhyncha hoge, 1946] from three mainland sites and three island sites along the eastern brazilian coast were analyzed. a total of six nematode species were recorded, with total nematode richness varying from one to four and overall nematode prevalences varying from 6.7% to 90.5% among host populations. number of nematode species per host individual (including all hosts, infected and uninfected) varied among host populations from 0.07 to 1.05, but most infected lizards in all six host populations harbored a single nematode species. both insular and continental populations of mabuya spp. exhibited generally poor nematode assemblages, and no clear tendency for insular host populations to have more depauperate nematode faunas and/or lower infection rates compared to mainland ones (or vice versa) was evident on the basis of the present data.
Territorial-like defensive behavior of floral resources by Heliconius ethilla narcaea Godart over H. sara apseudes (Hübner) (Lepidoptera, Nymphalidae, Heliconiinae)
Rocha, Carlos Frederico Duarte da;Duarte, Marcelo;
Revista Brasileira de Zoologia , 2001, DOI: 10.1590/S0101-81752001000500027
Abstract: the use of nectar and pollen of a bromeliad by two heliconiine butterflies, heliconius ethilla narcaea godart, 1819 and h. sara apseudes (hübner, [1813]) (lepidoptera, nymphalidae, heliconiinae), is herein reported. observations were made during a pollination study of aechmea gracilis lindman (bromeliaceae, bromelioidea) in a second-growth forest of the village vila dois rios, ilha grande, rio de janeiro state, southeastern brazil. field observations showed that h. ethilla can be more aggressive than h. sara in exploiting a. gracilis floral resources. temporal differences in the use of these resources were also observed: h. sara remained comparatively less time on flowers than h. ethilla.
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