991 resultados para III V material
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Datos de humedad de equilibrio de polvo de pulpa de lulo (PL) con y sin aditivos - 58% de maltodextrina (MD) o 58% de goma Arábiga (GA) - fueran determinados en las temperaturas de 20, 30, 40 y 50 °C utilizando el método estático gravimétrico para un rango de actividades de agua entre 0.06 y 0.90. Las isotermas presentaran formato sigmoidal del tipo III, y el modelo de Guggenhein-Anderson-de Boer (GAB) fue ajustado satisfactoriamente a los datos experimentales de humedad de equilibrio en función de la actividad de agua. La adición de encapsulantes afecto las isotermas de tal manera que en la misma actividad de agua, las muestras PL + GA y PL + MD presentaron un menor contenido de humedad de equilibrio y no fueron afectadas por la variación de temperatura. Los calores isostéricos de sorción de las pulpas en polvo con encapsulantes fueron mayores (menos negativos) con relación a las pulpas de lulo en polvo, sugiriendo la existencia de sitios polares más activos en el producto sin adición de GA o MD. Una relación exponencial empírica fue utilizada para describir la dependencia del calor de sorción con el contenido de humedad del material.
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In this work we have studied cyclooctene epoxidation with PhIO, using a new iron porphyrin, 5,10,15,20-tetrakis(2-hydroxy-5-nitrophenyl)porphyrinato iron(III), supported on silica matrices via eletrostatic interaction and / or covalent bonds as catalyst. These catalysts were obtained and immobilized on the solid supports propyltrimethylammonium silica (SiN+); propyltrimethylammonium and propylimidazole silica [SiN+(IPG)] and chloropropylsilica (CPS) via elestrostatic interactions and covalent binding. Characterization of the supported catalysts by UV-Vis spectroscopy and EPR (Electron paramagnetic resonance) indicated the presence of a mixture of FeII and FeIII species in all of the three obtained catalysts. In the case of (Z)-cyclooctene epoxidation by PhIO the yields observed for cis-epoxycyclooctane were satisfactory for the reactions catalyzed by the three materials (ranging from 68% to 85%). Such results indicate that immobilization of metalloporphyrins onto solid supports via groups localized on the ortho positions of their mesophenyl rings can lead to efficient catalysts for epoxidation reactions. The catalyst 1-CPS is less active than 1-SiN and 1-SiN(IPG), this argues in favour of the immobilization of this metalloporphyrin onto solids via electrostatic interactions, which is easier to achieve and results in more active oxidation catalysts. Interestingly, the activity of the supported catalysts remained the same even after three successive recyclings; therefore, they are stable under the oxidizing conditions.
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PURPOSE: To study morphologic and histochemical alterations arising at the ileocystoplasty site. METHODS: Sixteen Wistar female rats were subjected to ileocystoplasty and sacrificed after eight weeks. Material collected was divided into four groups for histological and histochemical studies: Group I (control) - isolated ileum segment removed during ileocystoplasty; Group II - ileoileal anastomosis; Group III - ileovesical anastomosis and Group IV - ileal segment from the neobladder. Histological and histochemical study assessed dysplasia, metaplasia, acute and chronic inflammation, fibrosis, atrophy, hypertrophy, total mucins, sialomucins and sulfomucins. The non-parametric Wilcoxon and Mann-Whitney tests were employed in statistical analysis. RESULTS: None of the groups presented dysplasia. Acute inflammation and atrophy occurred in Groups II, III and IV, not reaching statistical significance. Metaplasia was significant only in Group III (p=0.012). Chronic inflammation, fibrosis and hypertrophy were significant in Groups II, III and IV. There was a significant increase in total mucin content in Group IV (p=0.014) and a reduction in Group III (p=0.016). Increases in sialomucins were observed in samples for Groups III (p=0.003) and IV (p=0.002) along with reduced sulfomucins in samples from Groups III (p=0.013) and IV (p=0.008). CONCLUSION: Ileocystoplasty in female rats caused squamous metaplasia, chronic inflammatory infiltration, fibrosis, hypertrophy, increase in sialomucin content, reduction in sulfomucins, and alterations in total mucin content with statistical significance, as well acute inflammatory infiltration and muscular atrophy with less intensity.
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In Brazil, Hypnea musciformis is the main raw material for carrageenan production and the knowledge of nitrogen and phosphorus metabolism in algae is critical for the success of cultivation because these elements can limit seaweed productivity. Thus, the objective of this study was to evaluate the effects of nitrate (zero to 100 μM) and nitrate plus phosphate (zero to 25 μM) availabilities on the growth, the contents of photosynthetic pigments (phycobiliproteins and chlorophyll a) and proteins, and the photosynthesis and respiration of the brown (BR) and light green (LG) strains of H. musciformis. The results revealed metabolic differences between the colour strains of H. musciformis for nitrogen metabolism: upon nitrate addition, the LG strain stored nitrogen mainly as proteins, while the BR strain stored it as proteins and pigments. Moreover, the respiration of the LG strain and the photosynthesis of the BR strain increased with nitrate concentrations, indicating that the BR strain fixed more photosynthetic carbon than the LG strain.
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The present work has aimed to determine the 16 US EPA priority PAH atmospheric particulate matter levels present in three sites around Salvador, Bahia: (i) Lapa bus station, strongly impacted by heavy-duty diesel vehicles; (ii) Aratu harbor, impacted by an intense movement of goods, and (iii) Bananeira village on Maré Island, a non vehicle-influenced site with activities such as handcraft work and fisheries. Results indicated that BbF (0.130-6.85 ng m-3) is the PAH with highest concentration in samples from Aratu harbor and Bananeira and CRY (0.075-6.85 ng m-3) presented higher concentrations at Lapa station. PAH sources from studied sites were mainly of anthropogenic origin such as gasoline-fueled light-duty vehicles and diesel-fueled heavy-duty vehicles, discharges in the port, diesel burning from ships, dust ressuspension, indoor soot from cooking, and coal and wood combustion for energy production.
Metal-free synthesis of indanes by iodine(III)-mediated ring contraction of 1, 2-dihydronaphthalenes
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A metal-free protocol was developed to synthesize indanes by ring contraction of 1, 2-dihydronaphthalenes promoted by PhI(OH)OTs (HTIB or Koser's reagent). This oxidative rearrangement can be performed in several solvents (MeOH, CH3CN, 2 , 2, 2-trifluoroethanol (TFE), 1 , 1, 1, 3, 3, 3-hexafluoroisopropanol (HFIP), and a 1:4 mixture of TFE:CH2Cl2) under mild conditions. The ring contraction diastereoselectively gives functionalized trans-1, 3-disubstituted indanes, which are difficult to obtain in synthetic organic chemistry
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O objetivo do presente estudo é caracterizar a hidrodinâmica e o transporte de material particulado em suspensão (MPS) no estuário de Caravelas sob diferentes condições de maré e vazão fluvial. Foram realizadas quatro campanhas hidrográficas durante ciclos completos de maré, sendo em condições de maré de sizígia e quadratura, e durante os períodos seco e chuvoso. Dados de nível de água, velocidade e direção de correntes, salinidade, temperatura e turbidez foram obtidos em uma estação fixa próxima da desembocadura do estuário. A partir destes dados foram obtidos os transportes residuais de MPS e calculado os mecanismos de transporte. As maiores concentrações médias de material particulado em suspensão ocorreram em condições de sizígia. Em condições de maré de quadraturao transporte resultante de MPS foi com sentido estuário acima, porém de pequena intensidade. Em condições de sizígia o estuário é caracterizado por correntes mais intensas e assimétricas, com dominância de vazante. Durante a condição de sizígia o estuário pode atuar como importador ou exportador de MPS. O estuário do rio Caravelas foi classificado como bem misturado e fracamente estratificado. A hidrografia e o balanço sedimentar são principalmente modulados pela altura da marée o aporte de água doce é irrelevante.
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Oitenta e quatro espécies são registradas para o Estado do Maranhão: Prioninae (uma), Disteniinae (uma), Cerambycinae (49) e Lamiinae (33). O número total de espécies assinaladas para o Estado eleva-se a 367. Nove novas espécies são descritas em Cerambycinae: Chlorida inexpectata sp. nov. (Bothriospilini); Jupoata germana sp. nov. (Cerambycini); Eburodacrys separatus sp. nov. e Eburodacrys cincora sp. nov. (Eburiini); Ectenessa affinis sp. nov. (Ectenessini); Minibidion bicolor sp. nov. (Ibidionini, Tropidiina); Compsibidion maculatum sp. nov. e Compsibidion ytu sp. nov. (Ibidionini,Ibidionina); Ideratus beatus sp. nov. (Ideratini). Três espécies são descritas em Lamiinae: Aerenea gibba sp. nov. (Compsosomatini); Mimasyngenes barbozai sp. nov. (Desmiphorini); Cacostola exilis sp. nov. (Onciderini). Uma variação no colorido de Adesmus paradiana Galileo & Martins, 2004 é observada. Corrigenda de Piruana pulchra Martins et al., 2009 para Piruauna pulchra (Desmiphorini).
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Oxyommata Zajciw, 1970 e O. collaris (Audinet-Serville, 1833) são redescritos e comentados. Um novo gênero proveniente da divisão de Xenocrasis Bates, 1873 é descrito e três espécies alocadas nele: X. fulvicollis(Lacordaire, 1868); X. pubipennis (Fisher, 1952); e X. vestitipennis Zajciw, 1963. É apresentada chave para as espécies do novo gênero.
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The only specimen listed in the original description of Scyllarides deceptor Holthuis, 1963 is the holotype from São Paulo, Brazil, presently housed in the Leiden Museum. From the original description, however, it is clear that the new species was actually based on a number of additional specimens. Six of them exist in the collections of the Museum of Zoology in São Paulo, and are shown herein to be paratypes of S. deceptor. Scyllarides deceptor and S. brasiliensis Rathbun, 1906, continue to be confounded with one another, in consequence of their very similar color patterns and locally sympatric distributions. As many as 251,786 tons of slipper lobsters have been landed in Santa Catarina between 2000 and 2007. These catches have been attributed to S. deceptor alone and did not take into consideration the existence of a second species in the area, S. brasiliensis. Correct recognition of slipper-lobster species will be critical to properly evaluate the lobster stocks in southeastern Brazil. An opportunity is taken herein to elaborate on the taxonomy of S. deceptor and S. brasiliensis.
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Caracteres genéricos são ampliados para Irundisaua Martins & Galileo, 2005 (configuração das antenas; processo prosternal com largura menor ou igual à largura de uma procoxa; protíbias achatadas e fortemente alargadas para o ápice) ao qual se adicionam espécies transferidas de Acanthoderes Audinet-Serville, 1835: I. forsteri (Tippmann, 1960) comb. nov. do Peru e Brasil (Amazonas) e I. ucayalensis (Tippmann, 1960) comb. nov. do Equador, Peru e Brasil (Amazonas).Três novos gêneros são descritos: (1) Catuana comb. nov., espécie-tipo, C. thoracica (Tippmann, 1960) comb. nov., caracterizado pelo mesosterno com tubérculo; (2) Mundeu comb. nov., espécie-tipo, M. maculicollis (Bates, 1861) comb. nov., com protórax arredondado nos lados e protíbias alargadas; (3) Urangaua comb. nov., caracteriza-se pelos olhos finamente facetados e divididos, comprimento dos antenômeros III e IV subigual ao comprimento dos antenômeros V-XI em conjunto; é proposto para duas espécies: U. analis Melzer, 1935, comb. nov., espécietipo, e U. subanalis (Zajciw, 1964) comb. nov. Adiciona-se chave para as espécies de Urangaua.
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Novas espécies da Guiana Francesa são descritas e figuradas: Trestonia bilineta sp. nov. (Onciderini); Ischnolea odettae sp. nov. (Desmiphorini); Oreodera mageia sp. nov. (Acanthoderini) e Icupima ampliata sp. nov. (Hemilophini). Faz-se um novo registro de Plocaederus fragosoi (Cerambycini) para a Guiana Francesa.
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São discriminados em chave os gêneros semelhantes a Anoreina Bates, 1861, Trichoanoreina Julio & Monné, 2005 e Pyrianoreina gen. nov. Espécies novas descritas: Pyrianoreina piranga sp. nov. do Equador; P. hovorei sp. nov. da Bolívia; do Brasil Anoreina piara sp. nov. (Pará) e A. pinimaiuba sp. nov. (Amazonas); A. ayri sp. nov. do Equador.
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