Material de cama: qualidade, quantidade e efeito sobre o desempenho de frangos de corte

An experiment was conducted to evaluate performance, mortality and incidence of lesions on the breasts, hooks and foot pads of broilers raised on wood-scrap litter, rice hulls, Brachiaria hey (Brachiaria decumbens), Napier hay (Pennisetum purpureum) and Coast-cross hay (Cynodon dactylon). A randomized experimental design with five litters, two sexes, four replications and fifty birds per box was used. A standard litter height of 5 cm of wood-scraps and a weight of 20 250 g were adopted as criteria for use of other materials in the boxes. The amount of excreta deposited was 1697 g per raised bird (34,00 % of feed consumption). The incidence of lesions was evaluated in five birds per box after 35, 42 and 49 days and after slaughter. The criteria for scoring lesions were: 0 = without lesion; 1 = inflammation; 2 = mild ulceration; 3 = severe ulceration. At the end of experimental period (49 days) no differences were observed For weight, weight gain, feed consumption, feed/gain ratio and mortality among treatments. The lesions of the hocks and foot pads of the birds, raised on either Coast-cross hay and Napier hay, were more severe than those on wood-scraps and Brachiaria hay. Males showed better performance than females, but their hock lesions were more severe, independent of the litter used. Based on the performance and lesions scores, it was concluded that Braquiaria hay could be used as litter in replace wood-scraps and rice bulls.

Bibliographical review of the used tyre in concrete

Due to the progressive increase of vehicles, the number of used tires is globally one of the serious environmental problems faced now. Therefore, several researches have being developed for its reuse. The use of tires' rubber in the concrete is a possible form of its a pplication, aiming a the recycling of this material and the improvement of certain properties, as tenacity, impact resistance, thermal and acoustic isolation. This article presents conclusions that several researchers obtained using the rubberized concrete. Thus there were researched several works enclosing the period of 1993 to 2003, presenting then the results of some characteristics of this concrete such as: physical properties in fresh and hardened state, mechanical properties and properties that remit the durability. The bibliographical revision has as objective to subsidize future researches that can contribute to improve the use of this concrete in civil construction.

Mortar added by tyre rubber residues: Characterisation in fresh and hardened state

Due to the progressive increase of vehicles, the number of used tires is globally one of the serious environmental problems faced now. Therefore, several researches have being developed for its reuse. The use of tires' rubber in the concrete is a possible form of its application, aiming at the recycling of this material and the improvement of certain properties, as tenacity, impact resistance, thermal and acoustic isolation. This article presents conclusions that several researchers obtained using the rubberized concrete. Thus there were researched several works enclosing the period of 1993 to 2003, presenting then the results of some characteristics of this concrete such as: physical properties in fresh and hardened state, mechanical properties and properties that remit the durability. The bibliographical revision has as objective to subsidize future researches that can contribute to improve the use of this concrete in civil construction.

Sinterização de uma mistura de cavaco de aço inoxidável com pó do mesmo material. Uma nova tecnologia para a reciclagem de metais?

The reuse of materials has as its main objective to minimize environmental impacts and to rationalize the use of energy chains. In the present work, samples of scraps of 316 stainless steel mixed with powder of the same material were sintered. For this case, the percentage of scrap was varied from zero to 25% in weight, with 5% increases. After compacting, under a pressure of 600MPa, the samples were sintered simultaneously at a temperature of 1473 K. The mechanical behavior of the final product was evaluated through Assays of Transversal Rupture recommended and normalized by the MPIF - Metal Powder Industries Federation. Using Conventional Quantitative Metallography, the analyses of the sintered samples demonstrated regions of intense diffusion, therefore, regions of sufficiently intense sintering. The mechanical resistance of the samples was compared with the mechanical resistance of the sintered stainless steel with no scrap. The results were greater than expected, demonstrating the viability of this new procedure.

Variaciones del índice de cono en suelo movilizado posterior al tráfico de un tractor equipado con dos tipos de neumáticos y a cuatro velocidades de desplazamiento

The tractor is one of the machines that more traffics over the soil during the processes involving agricultural production. The interaction tractor/soil is made by the tires which, in most of the cases, are pneumatic. The tire type and the tractor travel speed, interfere directly on the pressure over the soil. One of the techniques employed to evaluate the alterations that tractor traffic causes in the soil is to measure its Cone Index. The aim of this research was to evaluate the same Cone Index alterations caused by an agricultural tractor equipped with both radial tires and bias ply tires, trafficking mobilized soil in four different travel speeds. The experiment was performed in a LATOSSOLO VERMELHO, located 22°51' S, 48°25'W and 770 m of altitude, in Botucatu-SP, Brazil. The soil mobilization was performed with a chisel plow and a disc arrow. The traction was accomplished with a John Deere tractor, model 6600, with 88 kW of power and 6,723 kg. Equipment requiring a force of 25kN was traced by the tractor draw bar. The experimental design was in randomized blocks with 4 × 2 factorial arrangements, with two distinct treatments corresponding to the types of tires (bias and radial) and the four travel speeds, with six replications. There were selected the following speeds: 3.5, 3.9, 5.1 and 5.9 km h-1. To determine the soil resistance, there was utilized MSSU - Mobile Soil Sampling Unit, with which the Cone Index was obtained in layers from 0-100, 100-200, 200-300, 300-400, 400-500 and over 500 mm deep. The Cone Index where evaluated in areas with non contact between tire and soil (ICn) and in the tire footprint track (ICp). There were calculated the Cone Index increments caused by the tractor tire (AIC) and the results showed that as the tractor travel speed increased, there were observed decrements in the medium values of cone index. The radial tire provided smaller values of the Cone Index in the superficial layer of the soil (0 to 100 mm) in relation to the bias ply tire, when the speed was approximately 6 km h-1. The increment in the Cone Index, promoted by the tractor, was more intense in the first 200 mm depth, but it also reached the layer from 200 to 300 mm.

Impact socioéconomique de la dégradation des terres en Haïti et interventions pour la réhabilitation du milieu cultivé

Incluye Bibliografía

Ensaios comparativos de mistura asfáltica pré-misturado a frio com adição de borracha de pneu

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Avaliação do consumo energético no preparo de solo para a cultura do algodão irrigado

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento de um perfilômetro laser para determinação da área e volume de contato entre o pneu e o solo: Cristiano Alberto de Paula. -

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Atributos físicos do solo em áreas de plantio direto com e sem escarificação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desempenho operacional e energético de um trator agrícola em função do tipo de pneu, velocidade de deslocamento, lastragem líquida e condição superficial do solo: Leonardo de Almeida Monteiro. -

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação das metodologias de derterminação das áreas de contato e deformações elásticas de pneus agrícolas em função das pressões de inflação e cargas radiais

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Desempenho de um trator agrícola em função do desgaste das garras dos pneus e das condições superficiais do solo

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

A reorganização do espaço da sala de educação infantil: uma experiência concreta à luz da teoria histórico-cultural

Pós-graduação em Educação - FFC

Aderência aço-concreto: uma análise do comportamento do concreto fabricado com resíduos de borracha

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)