118 research outputs found

    Lagoas de estabilização natural para armazenamento de dejetos líquidos de suínos.

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    Desenvolvimento das lagoas de bioestabilizacao; Impermeabilizacao de lagoas com manta de plastico.bitstream/item/37501/1/doc-9.pd

    Efeitos de tipos de comedouros e da forma física de rações sobre perdas de ração em suínos.

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    Comparacao de comedouros tipo EMBRAPA e convencional bem como suas forma fisica de racoes peletizada e farelada sobre perdas em suinos

    Extraction of Citric Acid by Liquid Surfactant Membranes: Bench Experiments in Single and Multistage Operation

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    The extraction of citric acid by liquid surfactant membranes (LSM) was performed using A/O/A emulsions, composed of sodium acetate aqueous solutions (inner phase), mixtures of Alamine 336 and ECA 4360 dissolved in Exxsol D240/280 (membrane phase), and citric acid aqueous solutions (feed phase). Two factorial designs (25–1 and 23) were used to define suitable operating conditions, in a single stage, producing citric acid solutions at 0.25 g mL–1 from aqueous feed solutions at 0.10 g mL–1. The parameters investigated and the best operating conditions obtained were pH of the feed phase (pH = 1.5), surfactant (ws = 2 %) and carrier concentration in the membrane phase (wc = 20 %), stirring speed (v = 145 rpm), and permeation time (t = 10 minutes) upon the citric acid concentration in the inner and feed phases, and inner phase swelling. Under these conditions, an extraction greater than 50 % and swelling equal to 80 % were obtained. Use of recycled membranes as well as extraction in multiple stages was also evaluated. Experiments of recycling revealed that the membranes can be reused for at least three times with good performance. Extraction in multiple stages showed high efficiency for the citric acid separation (~100 %) after three steps of operation

    Avaliação de esterco líquido de suínos e da adubação nitrogenada em cobertura na cultura do milho.

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    Com o objetivo de verificar o efeito da adubacao nitrogenada de cobertura na producao de milho quando se utiliza esterco liquido de suinos,foram conduzidos nos anos agricolas de 1985/87 no municipio de Patos de Minas, MG, em colaboracao com a Agroceres e EPAMIG estes experimentos. Os tratamentos utilizados foram: 45 m3/ha, 90m3/ha e 135m3/ha de esterco liquido de suinos, associados a 0, 30, 60 e 90 kg/ha de nitrogenio em cobertura, aos 40 dias apos a germinacao, utilizando-se para tal o hibrido simples AG 401. Foi utilizado o delineamento de blocos ao acaso em esquema de parcelas subdivididas com quatro repeticoes,sendo niveis de esterco na parcela e niveis de N na subparcelas. Os resultados do primeiro ano mostraram que os niveis de 90 m3/ha e 135 m3/ha de esterco liquido proporcionaram um incremento de producao na ordem de 7 e 12%, respectivamente, em relacao a 45 m3/ha. Nao houve diferenca significativa para producao de graos entre os niveis de 90 e 135m3/ha,. No segundo ano, a diferenca entre o nivel de 45 m3/ha ( 7.150kg/ha) e 135 m3/ha (8.200 kg/ha) foi de 15%, fato este devido ao efeito residual do esterco liquido acumulado de um ano para o outro. A media geral de produtividade do primeiro ano (6.100 kg/ha) para o segundo (7.750 kg/ha) aumentou em 1.650 kg/ha o que corresponde a 27%. Nao foi observado efeito da cobertura em nenhum dos anos, indicando que o esterco liquido de suinos nos niveis utilizados supriu as necessidades de nitrogenio da planta de milho para as produtividades alcancadas

    Budbreak induction in kiwifruit vines cultivated in an organic system by the biological method of single node cutting.

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    Kiwifruit vines are an alternative approach to diversify Brazilian fruit farming because of the low supply and increase in the demand for their fruits. Hydrogenated cyanamide, which is the most common rest-breaking agent, is highly toxic and its use is not allowed in organic production systems. This study aimed at evaluating the efficiency of alternative rest-breaking agents in kiwifruit vines by using the biological method of single node cutting. Twigs of the cultivar Bruno were collected in an organic orchard in Pelotas, a city located in Rio Grande do Sul state, Brazil. Seven-centimeter-long cuts with a single shoot at the ends were segmented. Cuttings were placed on plastic trays with phenolic foam and soaked in water, at 85% relative humidity on average, and kept in bio-oxygen demand (BOD) incubators at 25± 1 °C and a 16-h photoperiod. Budbreak was evaluated in 2-day and 3-day intervals. The experiment was conducted in a completely randomized design with ten treatments and three replications of ten sampling units each. The following variables were analyzed: average budbreak time (ABT), final budbreak rate (FBR), vigorous budbreak rate (VBR), velocity of budbreak (VB), percentage of open buds (POB) and dormancy index (DI). The rest-breaking agent garlic extract (GE) 10% + mineral oil (MO) 2% was the most efficient one in budbreak induction in both production cycles. Thus, this dose is recommended for budbreak induction in kiwifruit vines grown in an organic system

    Tipos de comedouros para suínos e efeito da forma física de rações sobre suas perdas

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    This experiment was carried out with the objective of comparing EMBRAPA’s prototype feeders (C1) and conventional feeders (C2), as well as two physical forms of rations, pelleted (R1) and meal (R2). The experimental design was the entirely randomized, with factorial structure 2 x 2 and with the experimental unit represented by the ration losses/pen/day. The utilized animals weighted 77.48 ± 0.48 kg, and the pens were of entirely stripped floor. An interaction statistically significant (P<0.01) was found among feeders and rations. Between C1 and C2 , R2 showed significantly (P<0.01) higher ration losses than R1 although proportionaly smaller for C2. The percentual loss of rations was 1.37 ± 0.58 and 0.99 ±0.22 for feeders C1 and C2, respectively.Este experimento foi conduzido durante o mês de outubro de 1982, tendo como objetivo a comparação de comedouros tipo EMBRAPA (C1) e convencional (C2), bem como a comparação de duas formas físicas de ração, peletizada (R1) e farelada (R2). O delineamento experimental foi o inteiramente casualizado, com estrutura fatorial 2 x 2. A unidade experimental foi representada pela perda de ração na baia, durante o dia. Os animais utilizados pesavam, em média, 77,48 ± 0,48 kg no início do experimento, e foram mantidos em baias de piso totalmente ripado. Foi constatada interação estatisticamente significativa (P<0,01) entre tipos de comedouros e forma física de ração. Dentro de C1 e C2, a R2 apresentou perda de ração significativamente maior (P<0,01) do que R1, embora, proporcionalmente menor em C2. A perda percentual de ração foi de 1,37 ±0,58 e 0,99% ± 0,22, para os comedouros C1 e C2, respectivamente
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