Influence of field slope and coffee plantation age on the physical properties of a red-yellow Latosol

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Energetic efficiency of an agricultural tractor in function of tire inflation pressure

The tire inflation pressure, among other factors, determines the efficiency in which a tractor can exert traction. It was studied the effect of using two tire inflation pressures, 110.4 kPa in the front and rear wheels, 124.2 kPa in the front wheel and 138 kPa in the rear wheels, the energetic efficiency of an agricultural tractor of 147 kW of engine power, in the displacement speed of 6.0 km.h-1, on track with firm surface, with the tractor engine speed of 2000 rpm. For each condition of the tire pressure, the tested tractor was subjected to constant forces in the drawbar of 45 kN and 50 kN, covering 30 meters. It was used a randomized complete block with a 2x2 factorial arrangement (tire pressure and drawbar power) with four replications, totaling 16 experimental units. Data were subjected to analysis of variance, using the Tukey test at 5% probability for comparison averages. The lowest hourly and specific fuel consumption, the lowest slippage of the wheelsets and the highest efficiency in the drawbar was obtained with the tire inflation pressure of 110.4 kPa in the front and rear tires of the tractor, highlighting that lower pressures improve energetic and operational performance of the tractor.

Crop optimization and pre-steps standardization to get a Bipolaris euphorbiae-based bioherbicide

Making bioproducts available to the market requires finding appropriate processes for mass production and formulation of biological agents. This study aimed at evaluating the Bipolaris euphorbiae production in a solid medium (fermentation in solid substrate) and in a biphasic system (growth in a liquid medium followed by growth in a solid medium), as well as determining the processes for collecting and drying conidia, under laboratory conditions. The influence of the incubation period and inoculum quantity were also investigated. The conidia were dried by using an oven (30ºC, 35ºC, 40ºC, 45ºC, 50ºC, 55ºC and 60ºC), and laminar flow, continuous air flow and aseptic chamber at room temperature. Dry conidia were obtained by sieving and grinding in a ball mill, hammer mill or grain grinder. The conidia viability and sporulation efficiency were evaluated in the solid medium and in the biphasic system. For growth period, the best sporulation on solid medium was obtained after 10 days of incubation, reaching 8.3 x 10(7) conidia g-1 of substrate. The biphasic system did not increase the B. euphorbiae sporulation (4.5 x 10(7) conidia g-1 of substrate), after 14 days, and the amount of liquid inoculum used in this system was not an important factor for increasing its production. The continuous air flow and laminar flow preserved the conidial viability (94.6% and 99.1%, respectively), while promoting a great moisture loss (62.6% and 54.0%, respectively). All the grinding processes reduced the conidia germination (86.2%, 10.5% and 12%, respectively), while sieving allowed the collecting of powdered conidia with high viability (94.8%).

Avaliação do potencial pozolânico da cinza de lodo de águas residuárias por meio de técnicas instrumentais

Pós-graduação em Engenharia Civil - FEIS

Estudo de geopolímeros utilizando cinzas residuais do bagaço de cana-de-açúcar

Pós-graduação em Engenharia Civil - FEIS

Análise microbiológica e físico-química de material proteico comestível derivado do processamento da gordura oriunda do abate de bovinos

Background: The use of all by-products of bovine slaughter is of high economic importance for the industries of products of animal origin. Among these products, fat has an important role, once fat rendering may generate several different products, such as protein material that may be used in the manufacture of meat products. However, in spite of the importance that the use of all by-products has for the economic balance of the industry, there are no reports on their use in Brazil, or studies that supply data on microbiological and physical-chemical local standards for this protein. Thus, the objective of this study was to evaluate microbiological and physical-chemical characteristics of protein material obtained from fat rendering, as well as to provide support for companies to use fat rendering to generate protein material, adding value to industrialized meat products.Materials, Methods & Results: The experimental production of edible protein obtained of fat rendering was conducted in slaughterhouse with supervision of the Brazilian Ministry of Agriculture, Livestock and Food Supply. Protein material was obtained in a continuous, humid heat system at high temperatures. Fat scraps containing protein were ground and cooked at high temperature (85 degrees C), and placed in a three phase decanter centrifuge. After centrifugation, protein material was ground again and packed. Samples were collected from 15 batches of protein material, and the following microbiological analyses were carried out: counts of aerobic mesophilic and psychrotrophic microorganisms, coliforms at 35 degrees C, Escherichia coli, sulfite-reducing Clostridium, and Staphylococcus aureus, besides presence or absence of Salmonella and Listeria monocytogens. The following physical-chemical analyses were also carried out: protein, total lipid, moisture, ash, carbohydrate, and energy content. Mean counts of mesophiles, psychrotrophs, and coliforms at 35 degrees C were 4.17; 3.69 and 1.87 (log CFU/g), respectively. Levels of protein, total lipids, moisture, ashes and carbohydrates were 27.50; 7.83; 63.88%; 0.24%; and 0.55%, respectively, and energy content was 182.63 kcal/100g.Discussion: Results of microbiological analyses demonstrated that, although low, the final product showed to be contaminated. Contamination that occurred during the second grinding procedure may be an explanation for these bacterial counts. Also, the temperature used for fat fusion was not enough to eliminate thermoduric microorganisms. However, even with the presence of indicator microorganisms in the samples, none was contaminated by E. coli, sulfite-reducing Clostridium, S. aureus, Salmonella or L. monocytogenes. Physical-chemical analyses showed that the product had adequate nutritional quality. Based on these results, it was possible to conclude that protein material obtained in fat rendering showed characteristics that enable the use of this product as raw material for processed meat products. Besides, the present study was the first one to present scientific results in relation to edible by-products obtained in fat rendering, supplying important information for slaughterhouses and meat-processing plants. The study also produced relevant data on the innocuousness of the product, which may be used to guide decision-making of health inspectors.

Feed type for induced molting of commercial layer hens

An experiment employing three hundred and twenty 81-week-old Lohmann LSL commercial-breed hens was conducted to compare alternative induced-molting methods with the conventional method (fasting). Induced molting lasted 28 days at most, production and quality being monitored for four periods of 28 days thereafter. A completely randomized experimental design with five treatments, eight replicates of eight birds each per plot was adopted. The following experimental treatments were applied until a loss of 26% of body weight was reached: T1 - fasting, T2 - wheat bran ad libitum, T3 - rice bran ad libitum, T4 - cracked rice ad libitum, T5 - ground alfalfa ad libitum. Birds were then fed production diet ad libitum, except for those on treatment T1 (fasting) which received 30, 60 and 100 g/bird/day and then feed ad libitum. During induced molting the birds were exposed to a natural photoperiod and at day 28 that period was increased by 30 minutes/week until reaching 16 hours of light/day. The characteristics evaluated during induced molting were: feed intake, body weight changes and laying percentage. In the post-molt period, performance (feed intake, laying percentage, egg weight, egg mass, feed conversion ratio per dozen and per egg mass and percentage of broken eggs) and egg quality (specific gravity, eggshell breaking strength, percentages of eggshell, yolk, and albumen, eggshell thickness, yolk color and Haugh unit) were evaluated. Every 28 days one egg was collected from each repetition for three consecutive days for quality assessment. The use of rice bran and wheat bran is viable as molting inducers since the birds given those treatments display performance and egg quality similar to those fasted during the induced molting and also because these ingredients promote easier handling, eliminates the need for grinding and feed-mixing equipment and, being less aggressive, provide greater bird welfare.

Morphological characteristics of the Pterodoras granulosus digestive tube (Valenciennes, 1821) (Osteichthyes, Doradidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Functional Morphology of the Crop and Proventriculus of Sitophilus zeamais (Coleoptera: Curculionidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Low-temperature degradation of a Y-TZP ceramic after surface treatments

The purpose of this study was to evaluate the influence of zirconia surface treatments on low-temperature degradation (LTD). Disc-shaped specimens were subjected to one of four surface treatments, denoted as C (controlno surface treatment), Si (air abrasion with 30 mu m silica-modified alumina particles), Al (air abrasion with 30 mu m alumina particles), and Gr (grinding with 120 grit diamond discs). Half of the samples were submitted to autoclave treatment for 12 h (127 degrees C, 1.5 bar). Samples were characterized by x-ray diffraction and profilometer analysis and were subjected to biaxial flexural strength test. All of the groups exhibited an increase in the amount of monoclinic phase (m-phase) after LTD. The tm transformation was remarkable for the specimens from the C group, which also exhibited a significant increase in strength. The Gr group also exhibited an increase in strength but lower initial roughness, which probably suppressed LTD on the zirconia surface. The specimens subjected to air abrasion exhibited higher initial amounts of m-phase and a small increase in m-phase after LTD; the strength was not affected in these groups. The effects of LTD were different with each surface treatment applied. Apparently, LTD may be suppressed by smoother surfaces or the presence of an initial amount of m-phase on zirconia surface. (c) 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 101B: 1387-1392, 2013.

A New and Simple Visual Technique Based on Indigo Dye for Determination of Ozone in Ambient Air

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of shot peening on the fatigue strength of Custom 465 stainless steel for aeronautic application

This project was originated from the national aircraft industry requirements to reduce the use of coated materials with electroplated chromium or cadmium that produce waste, which is harmful to health or the environment. The selected material is a Custom 465 stainless steel used in the aeronautical field due to its high mechanical strength. Considering the load sustained by the wheel axis of the landing gear, the Custom 465 is tested in axial fatigue. The objective is to compare the behavior of the Custom 465 with plated AISI 4340 steel coated with cadmium. X-ray diffraction method was used to determine the residual stress field induced by shot peening.

Silicone insulators of power transmission lines with a variable inorganic load concentration: Electrical and physiochemical analyses

Polymeric insulation is an increasing tendency in projects and maintenance of electrical networks for power distribution and transmission. Electrical power devices (e. g., insulators and surge arresters) developed by using polymeric insulation presents many advantages compared to the prior power components using ceramic insulation, such as: a better performance under high pollution environment; high hydrophobicity; high resistance to mechanical, electrical and chemical stresses. The practice with silicone insulators in polluted environments has shown that the ideal performance is directly related to insulator design and polymer formulation. One of the most common misunderstandings in the design of silicone compounds for insulators is the amount of inorganic load used in their formulation. This paper attempts to clarify how the variation of the inorganic load amount affects physicochemical characteristics of different silicone compounds. The physicochemical evaluation is performed from several measurements, such as: density, hardness, elongation, tensile strength. In addition, the evaluation of the physicochemical structure is carried out using infrared test and scanning electronic microscopy (SEM). The electrical analysis is performed from the electric tracking wheel and erosion test, in agreement with the recommendation of the International Electrotechnical Commission (IEC). (C) 2014 Elsevier Ltd. All rights reserved.

Estudo comparativo da eficacia de dois adesivos dentinarios e um cimento de ionomero de vidro empregados na adesão do amalgama a dentina

Pós-graduação em Odontologia Restauradora - ICT

Avaliação laboratorial da resistência ao cisalhamento de discos de porcelana e de um polímero de vidro cimentados à dentina bovina com o emprego de cimentos adesivos

Pós-graduação em Odontologia Restauradora - ICT