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Search Results: 1 - 10 of 742210 matches for " F. A. S.;Prestes "
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Sele??o de concretos refratários densos antierosivos para unidades de craqueamento catalítico fluidizado de petróleo
Serra, F. A. S.;Prestes, E.;Medeiros, J.;Veiga, J. L. B. C.;Pandolfelli, V. C.;
Ceramica , 2012, DOI: 10.1590/S0366-69132012000100003
Abstract: in the petrochemical industry the fluidized catalytic cracking unit is an important vessel for refractory castables application due the necessity of obtaining specialized products. usually, the selection of these materials is based on the chemical analysis, apparent density, cold crushing strength and cold erosion test. for the evaluation of the present selection requirements, five high-alumina castables, being three of low cement and two conventional of commercial use, were characterized under cold crushing strength and cold erosion tests. additional tests that are actually not used in the selection were also performed, such as: thermal shock cycling, hot modulus of rupture and carbon deposition by co atmosphere exposure. the analysis showed that the present specifications are mainly based in the experience with the use of products not designed for this application and that the development of more suitable castables is inhibited due to the close restrictions of the present specifications. it is also verified that the materials selection is limited by the absence of tests for the performance evaluation next to in-service conditions. in this sense, the carbon deposition test by co atmosphere exposure was interesting in order to provide the better selection of dense antierosive refractory castables.
Avalia??o funcional e histológica da tireoide de ovinos suplementados com fluoreto de sódio por um período de 150 dias
Prestes, D.S.;Filappi, A.;Schossler, D.R.;Duarte, F.A.;Dressler, V.L.;Flores, E.M.M.;Cecim, M.;
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 2009, DOI: 10.1590/S0102-09352009000200002
Abstract: the effect of sodium fluoride administration on thyroid function and morphology in sheep was evaluated using 12 lambs. animals were allotted in two groups: control that received 5g nacl + 0.2ppm i/kg dm and treated which received the same treatment plus sodium fluoride (4.7mg f/kg bw), daily, for 150 days. blood samples were collected for determination of f, i, t3, and t4. urine production was collected for measurement of f and i. after euthanasia at 150 days of treatment, thyroid glands were removed for analysis. no differences were found between or within groups for urinary i. also, no differences were found for t3 and t4 on serum i between groups or among time points. no histological alterations were found in the thyroids. in conclusion, chronic sodium fluoride treatment did not affect thyroid function and morphology in lambs.
Caracteriza??o genética e fenotípica de isolados de Pyricularia grisea do trigo
Cruz, Maria Fernanda A.;Maciel, Jo?o L.N.;Prestes, Ariano M.;Bombonatto, Estevon A.S.;Pereira, Jorge F.;Consoli, Luciano;
Tropical Plant Pathology , 2009, DOI: 10.1590/S1982-56762009000600005
Abstract: the use of molecular tools and virulence evaluations of pyricularia grisea, the causal agent of rice and wheat blast, has permitted identification of strains of the pathogen, especially those occurring in the rice crop. microsatellites have already demonstrated efficiency to classify p. grisea isolates by genetic similarity groups. the objectives of this work were to characterize the genetic diversity of 18 isolates of p. griseacollected from wheat by applying 8 microsatellite primers; and to compare the molecular and virulence results of isolates, when inoculated in seedlings of 70 wheat genotypes. the most informative primer was pg 5 with 4 alleles. the primers mg 21 and pg 12 permitted separation of py 5020 and py 5038 in distinct groups, with less than 50% similarity in relation to others. the genetic similarity of isolates presented more than 75% similarity among them. in the virulence analysis, 15 out of 18 tested isolates showed more than 85% of similarity. the molecular pattern and virulence were similar for the isolates, except for py 5002 isolate. the absence of resistance to all isolates confirms the need to seek new sources or better genetic combinations of wheat that are more resistant to disease.
Efeitos da suplementa??o de fibras solúveis sobre as células do sistema imune após exercício exaustivo em ratos treinados
Donatto, Felipe F.;Prestes, Jonato;Ferreira, Clílton K.O.;Dias, Rodrigo;Frollini, Anelena B.;Leite, Gerson S.;Urtado, Christiano B.;Verlengia, Rozangela;Palanch, Adriane C.;Perez, Sérgio E.A.;Cavaglieri, Cláudia R.;
Revista Brasileira de Medicina do Esporte , 2008, DOI: 10.1590/S1517-86922008000600011
Abstract: exercise modality, volume, intensity, as well as physical fitness and nutritional factors may modulate the immune response. the purpose of this investigation was to verify the effects of chronic oat bran supplementation on immune cells in trained rats submitted to an extenuating test. wistar rats (two months old), +200g weight, divided into three groups (n = 9, per group) were used: 1) a sedentary control (c) 2) trained for eight weeks submitted to an exhaustion test (ex), and 3) trained for eight weeks submitted to an exhaustion test with 30% oat bran supplementation (exa). training consisted of 60 daily minutes of swimming, five days a week, during eight weeks. the analyses conducted were: total leukocytes, lymphocytes from lymph nodes, peritoneal macrophages and peritoneal macrophages phagocytic capacity. statistical analyses were done by the two-way anova test, followed by tukey's post hoc test (p < 0.05). ex group presented leukocytosis when compared to control; however, exa group did not. in exercised group, comparison with exa has shown lower leukocytosis in relation to ex. no significant alteration was observed for tissue lymphocytes in any of the exercised groups. the number of peritoneal macrophages as well as phagocytic capacity of this cell was higher in exercised groups. in oat bran supplemented group the phagocytic capacity was higher as compared to exhaustion group without oat bran. soluble fibers supplementation has shown benefic results with regard to immune alterations induced by exhaustive exercise, and increased peritoneal macrophages phagocytic capacity in rats trained for eight weeks submitted to an exhaustion test.
A Transmission Power Self-Optimization Technique for Wireless Sensor Networks
F. Lavratti,A. Ceratti,D. Prestes,A. R. Pinto
ISRN Communications and Networking , 2012, DOI: 10.5402/2012/720286
Post mortem analysis of burned magnesia-chromite brick used in short rotary furnace of secondary lead smelting
Prestes, E.;Chinelatto, A. S. A.;Resende, W. S.;
Ceramica , 2009, DOI: 10.1590/S0366-69132009000100008
Abstract: burned magnesia-chromite bricks are the standard product for the lining of furnaces in lead industry, where the short service life is a great problem. used sintered magnesia-chromite brick sample from short rotary furnace lining, sent by a secondary lead manufacturer, showed parallel cracks to the hot face due to structural spalling damage. the refractory infiltrated region and slag interface were analyzed using a scanning electron microscope with an energy dispersive spectroscopy analyzer, and x-ray diffraction powder analysis. crucible corrosion test was performed to evaluate the influence of slag attack. the results showed that the structural spalling was due to strong pb-infiltration of the refractory microstructure by bath components of the furnace (metallic lead and lead sulphite) during the reduction process and that the slag infiltration had little contribution due to the good resistance of the magnesia-chromite bricks to feo rich slag attack.
Gilmar Senna,Belmiro F. Salles,Jonato Prestes,Rafael A. Mello
Journal of Sports Science and Medicine , 2009,
Abstract: Rest intervals between sets appear to be an important variable that can directly affect training volume and fatigue. The purpose of the present study was to compare the influence of two and five-minute rest intervals on the number of repetitions per set, per exercise and total repetitions in resistance training sessions. Fourteen trained men (23.0 ± 2. 2 yrs; 74.9 ± 4.1 kg; 1.75 ± 0.03 m) completed three sets per exercise, with 10RM load in four training sessions. Two sessions involved lower body exercises (leg press, leg extension and leg curl), with two-minute (SEQA) and with five-minute interval (SEQB). The other two sessions involved upper body exercises (bench press, pec-deck and triceps pulley), with two (SEQC) and five-minute intervals (SEQD). For two-minute, five of six exercises presented reductions in the second set, compared with the first set, and for the third set compared with the first and second sets. For five-minute, three of the six exercises presented reductions in the third set, compared with the first sets, and two of the six for the third set, compared with the second sets. The total number of repetitions in SEQA (66.7 ± 4.9) was significantly smaller than in SEQB (80.9 ± 6.9). Similarly, the total repetitions was significantly lower in SEQC (71.1 ± 4.7) compared with SEQD (83.7 ± 6.1). The results indicate that the training session performance is reduced by shorter intervals, being the initial exercises less affected during the progression of the sets
Avalia o da estabilidade físico-química de emuls o acrescida de uréia dispersada, ou n o, em propilenoglicol
Revista de Ciências Farmacêuticas Básica e Aplicada , 2009,
Abstract: Normalmente uma formula o pode ser manipulada de diversas maneiras, devendo-se sempre optar pela técnica que forne a o produto mais estável e homogêneo. Alguns farmacêuticos a fim de facilitar e acelerar a manipula o dispersam a uréia em propilenoglicol antes de proceder a homogeneiza o da mesma no veículo, enquanto outros profissionais acreditam que essa técnica pode ocasionar instabilidade física no produto final e por isso acrescentam o veículo diretamente na uréia. Logo, o objetivo deste estudo foi analisar o comportamento reológico e a estabilidade física de formula es acrescidas de 10% de uréia manipuladas com, ou sem, a adi o de propilenoglicol. Foi realizado o estudo de Estabilidade acelerada, com dura o de 180 dias. As formula es foram armazenadas em temperatura ambiente (25°C±2), geladeira (5°C±2) e estufa (37°C±2) e as leituras foram feitas nos tempos 24 horas (T1), 15 dias (T15) e 180 dias (T180), onde foram analisadas as características organolépticas, teste de centrífuga, determina o do pH, viscosidade e comportamento reológico. Os resultados obtidos neste estudo mostraram que a presen a do propilenoglicol melhorou a estabilidade física da emuls o acrescida de uréia, a longo prazo. Palavras-chave: Uréia. Propilenoglicol. Reologia. Estabilidade.
Ocorrência de Lysiphlebus testaceipes (Cresson) (Hymenoptera: Aphidiidae) parasitando pulg?es (Hemiptera: Aphididae), em trigo em Medianeira, PR
Zanini, Agostinho;Prestes, Tania M.V.;Dalmolin, Maria F.;Alves, Luis F.A.;Menezes Jr., Ayres de O.;
Neotropical Entomology , 2006, DOI: 10.1590/S1519-566X2006000200020
Abstract: this paper records the occurrence of lysiphlebus testaceipes (cresson) attacking aphids in wheat plantation in medianeira, in the west region of paraná state, brazil. this microhymenoptera was introduced and released by embrapa trigo, from 1978 to 1992 in the wheat production region at the state of rio grande do sul, what suggests that individuals of this species may show high dispersal ability.
Production of 15N-enriched nitric acid (H15NO3)
Sant Ana Filho, C. R.;Bendassolli, J. A.;Rossete, A. L. R. M.;Piedade, S. M. S.;Prestes, C. V.;
Brazilian Journal of Chemical Engineering , 2008, DOI: 10.1590/S0104-66322008000400011
Abstract: techniques that employ 15n have proved to be an important tool in many areas of the agronomic and biomedical sciences. nevertheless, their use is limited by methodological difficulties and by the price of compounds in the international market. nitric compounds (15no3-) have attracted the interest of researchers. however, these compounds are not currently produced in brazil. thus, in the present work h15no3 was obtained from the oxidation of anhydrous 15nh3. the method we used differs from the industrial process in that the absorption tower is replaced with a polytetrafluoroethylene-lined, stainless-steel hydration reactor. the process output was evaluated based on the following parameters: reaction temperature; ratio of reagents; pressure and flow of 15nh3(g) through the catalyst (pt/rh). the results showed that, at the best conditions (500 oc; 50 % excess o2; 0.4 mpa; and 3.39 g.min-1 of 15nh3), a conversion percentage (n-15nh3 to n-15no3-) of 62.2 %, an overall nitrogen balance (n-15nh3 + n-15no3-) of 86.8 %, and purity higher than 99 % could be obtained.
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