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Search Results: 1 - 10 of 2180 matches for " Tadeu Messias Donizete; "
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Compara??o do desempenho operacional e das características do cord?o na soldagem com diferentes arames tubulares em polaridade negativa
Starling, Cícero Murta Diniz;Modenesi, Paulo José;Borba, Tadeu Messias Donizete;
Soldagem & Inspe??o , 2011, DOI: 10.1590/S0104-92242011000400006
Abstract: this paper compares the bead characteristics of welds deposited of carbon steel tubular wires. three tubular wires of 1.2mm produced in brazil were used: rutilic (asme sfa-5.20: e71t-1/e71t-9/e71t-9m), basic (asme sfa-5.20: e71t-5/e71t-5m) and metal cored (asme sfa-5.18: e70c-3m). welding trials were performed in downhand position on thick (12 mm) low-carbon steel plates using a constant voltage power supply in negative wire polarity (cc-). welding current and voltage, and wire feed rate were monitored in all trials. for each tubular wire type, the shielding gas composition (75%ar-25%co2 and 100%co2) and wire feed rate (7 and 9 m/min) were changed, and other process variables, including electrode and arc lengths (16 mm and 3.5 mm, respectively) were kept constant throughout the experimental program. weld bead geometry parameters (penetration depth, reinforcement, width, fused and deposited areas, and weld dilution), presence of weld discontinuities, fusion zone microstructure and hardness were measured and compared for the different tubular wires. operational conditions that yielded weld bead characteristics favored for the welding of thick plates of structural steels on negative wire polarity were determined.
Caracteriza??o do cord?o na soldagem FCAW com um arame tubular "metal cored"
Starling, Cícero Murta Diniz;Modenesi, Paulo José;Borba, Tadeu Messias Donizete;
Soldagem & Inspe??o , 2011, DOI: 10.1590/S0104-92242011000300010
Abstract: this work evaluates the relationship between operational conditions and the characteristics of weld beads deposited with a 1.2 mm produced in brazil metal cored tubular wire (asme sfa-5.18: e70c-3m). welding trials were performed in downhand position on 12mm thick low-carbon steel plates using a constant voltage power supply. welding current and voltage, and wire feed rate were monitored in all trials. while the shielding gas composition (75%ar-25%co2 and 100%co2), wire polarity, and wire feed rate (7 and 9 m/min) were changed, other process variables, including electrode and arc lengths (16 mm and 3.5 mm, respectively) were kept constant throughout the experimental program. weld bead geometry parameters (penetration depth, reinforcement, width, fused and deposited areas, and weld dilution), presence of weld discontinuities, microstructure, and fusion zone hardness were measured and correlated to the operational conditions. operational conditions that yielded both high productivity levels (high deposition rates) and weld bead characteristics favored for the welding of thick plates of structural steels were determined.
Compara??o do desempenho operacional e das características do cord?o na soldagem com diferentes arames tubulares
Starling, Cícero Murta Diniz;Modenesi, Paulo José;Borba, Tadeu Messias Donizete;
Soldagem & Inspe??o , 2009, DOI: 10.1590/S0104-92242009000100003
Abstract: this paper compares the bead characteristics of welds deposited of carbon steel tubular wires. three tubular wires of 1.2 mm produced in brazil were used: rutilic (asme sfa-5.20: e71t-1/e71t-9/e71t-9m), basic (asme sfa-5.20: e71t-5/e71t-5m) and metal cored (asme sfa-5.18: e70c-3m). welding trials were performed in downhand position on thick (12 mm) low-carbon steel plates using a constant voltage power supply. welding current and voltage, and wire feed rate were monitored in all trials. for each tubular wire type, the shielding gas composition (75%ar-25%co2 and 100%co2) and wire feed rate (7 and 9 m/min) were changed, and other process variables, including electrode polarity (cc+), electrode and arc lengths (16 mm and 3.5 mm, respectively) were kept constant throughout the experimental program. weld bead geometry parameters (penetration depth, reinforcement, width, fused and deposited areas, and weld dilution), presence of weld discontinuities, fusion zone microstructure and hardness were measured and compared for the different tubular wires. operational conditions that yielded weld bead characteristics favored for the welding of thick plates of structural steels were determined.
Caracteriza??o do cord?o na soldagem FCAW com um srame tubular rutílico
Starling, Cícero Murta Diniz;Modenesi, Paulo J.;Borba, Tadeu Messias Donizete;
Soldagem & Inspe??o , 2009, DOI: 10.1590/S0104-92242009000400004
Abstract: this paper studies the effect of operational conditions on bead shape characteristics in fca welding with a brazilian made wire with rutilic flux (asme sfa-5.20: e71t-1/e71t-9/e71t-9m) of 1.2mm diameter. bead-on-plate downhand welding trials were performed on 12mm thick low carbon steel plates with a constant voltage power supply. a digital data logging system was used to measure the welding current and voltage, and wire feed rate. while the shielding gas composition (75%ar-25%co2 and 100%co2), wire polarity and feed rate (7 and 9m/min) were varied during the trials, the electrode extension (16mm) and arc length (3.5mm) were not changed. weld bead characteristics (penetration depth, width, and fused and deposited areas), the presence of discontinuities, bead microstructure and hardness were evaluated. welding conditions of high productivity (high deposition rate) associated to adequate bead characteristics were determined for the wire.
Avalia??o de sistema alternativo de automa??o da irriga??o do feijoeiro em casa de vegeta??o
Queiroz, Tadeu M. de;Carvalho, Jacinto de A.;Rabelo, Giovanni F.;Andrade, Messias J. B.;
Engenharia Agrícola , 2005, DOI: 10.1590/S0100-69162005000300008
Abstract: the present work aimed at evaluating an alternative controller for automatic irrigation management systems with adapted tensiometers. common bean (phaseolus vulgaris l.) was cultivated under four levels of water deficit (y) (15; 30; 45 and 60 kpa) and three irrigation management methods (m), two of them automated using tensiometers with a mercury vacuum meter (hg) and tensiometers with a bourdon vacuum meter (vc), both adapted, and the third using conventional management with a portable digital tensiometer (ts). the controller's operation was evaluated considering the applied volume, number of times the system started, yield and water use efficiency. it was observed that both yield and water use efficiency was not affected by the irrigation methods (5% of probability). the variable applied volume was affected (1% of probability) by the methods (m) and by the tensions (y) as well as by their interaction (mxy). despite operating problems presented by the adapted bourdon tensiometer/bourdon-type tensiometer, the controller applied the right amount of water at the right time.
Comportamento de cultivares de feijoeiro-comum em sistema convencional e plantio direto com diferentes palhadas
Santos, Raimundo Luíz Laurinho dos;Corrêa, Jo?o Batista Donizete;Andrade, Messias José Bastos de;Morais, Augusto Ramalho de;
Ciência e Agrotecnologia , 2004, DOI: 10.1590/S1413-70542004000500003
Abstract: four field experiments were carried out in lavras (south region of minas gerais state) during three seeding seasons whit the purpose of studying the agronomical performance of common beans cultivars from different commercial groups by using both the conventional and no-tillage systems on different soil coats. the treatments were arranged in a split block schema. a randomized block design was used with four replications. in the first three experiments, six cultivars (ouro negro, talism?, carioca, pérola, rox?o and jalo esal) and four planting systems (conventional and no-tillage on oat, wheat and bare soil straw) were used in the treatments. the same statistical design and the same cultivars were used in the fourth experiment. however, only three planting systems (conventional and no-tillage on oat and bare soil straws) were used. the amount of straw used in no-tillage system, as well as the beans plants and the grain yield, was estimated. the beans cultivars agronomical performances were modified by the planting system, especially by the seeding seasons. in general, the black-grain ouro negro cultivar has performed better than the carioca-grain ones (talism?, carioca, and pérola). the cultivars with the biggest grains were those that have had the worst performance. the highest grain yields were achieved in the winter-spring irrigated season, followed by the rain season, and finally the dry season. at more favorable environmental conditions the no-tillage system was found to surpass the conventional one. the no-tillage on bare soil straw promotes better grain yield at less favorable environmental conditions.
Balan?o de potássio e desempenho de frangos de corte suplementados com KCl no ver?o
Souza, Bonifácio Benicio de;Bertechini, Ant?nio Gilberto;Santos, Custódio Donizete dos;Lima, José Augusto de Freitas;Teixeira, Ant?nio Soares;Freitas, Rilke Tadeu Fonseca de;
Ciência e Agrotecnologia , 2004, DOI: 10.1590/S1413-70542004000500026
Abstract: this experiment was conducted to verify the effect of kcl on potassium balance and performance of broilers in summer. a total of 288 broiler chickens aged 28 to 49 days was utilized, allocated according to a completely randomized design in a 6 x 2 factorial scheme 6 levels of kcl (0,0; 0,4; 0,8; 1,2; 1,6; 2,0 %) and 2 sexes, with four replications of 6 birds each. the maximum and minimum temperatures, relative humidity and black globe-humidity index (bghi) were of 31,5oc and 20oc, 68% and of 73%, respectability. with the growing supplementation of kcl, there was a linear increase (p<0.01) in the intake, excretion and retention of the potassium, concentration of potassium in the plasma and water consumption. there was a linear reduction (p<0.01) of the excreta dry matter. the males overcame the females (p<0.01) in the intake and excretion of potassium. however, the females overcame the males (p<0.01) in the retention of the potassium. there was a positive balance of potassium for the males as for the females. there was no difference for the performance of the broilers.
Resistance of tomato genotypes with high level of acylsugars to Tetranychus evansi Baker & Pritchard
Resende, Juliano Tadeu Vilela de;Maluf, Wilson Roberto;Cardoso, Maria das Gra?as;Faria, Marcos Ventura;Gon?alves, Luciano Donizete;Nascimento, Ildon Rodrigues do;
Scientia Agricola , 2008, DOI: 10.1590/S0103-90162008000100005
Abstract: the lycopersicon pennellii accession la716 has been used as a source of arthropod pest resistance in tomato breeding programs due the high contents of acylsugars presents in its leaflets. we investigated the relationship between high foliar acylsugar contents and repellence to spider mite tetranychus evansi in plants with contrasting acylsugar levels, selected from f2 and bc1f2 (= f2 of the first backcross towards l. esculentum) generations derived from the interespecific cross l. esculentum 'tom-584' ′ l. pennellii la716. mite resistance was assessed by a repellence test. plants selected for high levels of acylsugars in leaflets had mite repellence levels similar to that of la716. the high correlation confirmed the association between high acylsugar levels and mite repellence.
Periodic perturbations of quadratic planar polynomial vector fields
MESSIAS, MARCELO;
Anais da Academia Brasileira de Ciências , 2002, DOI: 10.1590/S0001-37652002000200001
Abstract: in this work are studied periodic perturbations, depending on two parameters, of quadratic planar polynomial vector fields having an infinite heteroclinic cycle, which is an unbounded solution joining two saddle points at infinity. the global study envolving infinity is performed via the poincaré compactification. the main result obtained states that for certain types of periodic perturbations, the perturbed system has quadratic heteroclinic tangencies and transverse intersections between the local stable and unstable manifolds of the hyperbolic periodic orbits at infinity. it implies, via the birkhoff-smale theorem, in a complex dynamical behavior of the solutions of the perturbed system, in a finite part of the phase plane.
O riso como express?o de um modo de entendimento: do bergsonismo à antropologia
Basques, Messias;
Scientiae Studia , 2011, DOI: 10.1590/S1678-31662011000100006
Abstract: this article analyzes the relationship between life and laughter in the philosophy of henri bergson based on a brief reflection on its possible contributions to anthropology. using the concepts of intuition and intelligence, i intend to analyze laughter as a particular way of understanding that establishes an epistemological asymmetry between scientific experts and the lay public.
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