1000 resultados para Concentração afluente
Resumo:
Vitamin A is an essential nutrient for many physiological processes such as growth and development, so that their adequate nutritional state is essential during pregnancy and lactation. Lactating women and children in breastfeeding are considered risk groups for vitamin A deficiency and some factors may increase the risk of vitamin A deficiency, such as prematurity. The aim of this work was to evaluate the vitamin A concentration in preterm and term lactating women and newborns by determination of retinol in maternal serum, umbilical cord serum and breast milk collected until 72 hours postpartum. 182 mothers were recruited and divided into preterm group (GPT; n = 118) and term group (GT, n = 64). In preterm group were also analyzed transition milk (7th-15th day; n = 68) and mature milk (30th-55th day; n = 46) samples. Retinol was analyzed by high-performance liquid chromatography (HPLC). Maternal retinol concentration in serum was 48.6 ± 12.3 µg/dL in GPT and 42.8 ± 16.3 µg/dL in the GT (p <0.01). Cord serum retinol was 20.4 ± 7.4 µg/dL in GPT and 23.2 ± 7.6 µg/dL in GT (p> 0.05). Among newborns, 43% of premature and 36% of term had low levels of serum retinol in umbilical cord (<20 µg/dL). In colostrum, the retinol in preterm and term groups had an average of 100.8 ± 49.0 µg/dL and 127.5 ± 65.1 µg/dL, respectively (p <0.05). The retinol average in preterm milk increased to 112.5 ± 49.7 µg/dL in transition phase and decreased to 57.2 ± 23.4 µg/dL in mature milk, differing significantly in all stages (p <0.05). When comparing with the recommendation of vitamin A intake (400 µg/day) GT colostrum reached the recommendation for infants, but in GPT the recommendation was not achieved at any stage. Mothers of premature infants had higher serum retinol than mothers at term; however, this was not reflected in serum retinol of umbilical cord, since premature had lower concentration of retinol. Such condition can be explained due to lower maternal physiological hemodilution and placental transfer of retinol to the fetus during preterm gestation. Comparison of retinol in colostrum showed lower concentrations in GPT; however the transition phase there was a significant increase of retinol content released by the mammary gland of preterm mothers. This situation highlights a specific physiological adaptation of prematurity, likely to more contribute to formation of hepatic reserves of retinol in premature infants.
Resumo:
Vegetable oils are characterized as important raw materials in the supplying of natural substances of interest pharmaceutical, food and cosmetic industry. Sunflower oil stands out for its important composition present in unsaturated fatty acids such as oleic acid (C18:1) and linoleic (C18:2), responsible for many health benefits. The main objective of this study is obtain enriched fractions in unsaturated compounds from refined sunflower oil. The oil used in this study was characterized by the determination of some properties, like iodine number, acid number and viscosity. A transesterification was done to transform the triglycerides into their corresponding methyl esters of fatty acids. These was submitted the molecular distillation process, for present as an efficient alternative to separation and purification of these substances, using high vacuum and low temperatures. Of the esters fractions that was obtained, were analyzed by gas chromatography. The experimental design technique was used to evaluate the influence of the temperature variation of evaporation and condensation system on the percentage obtained residue. The evaporator temperature proved to be the most influential variable on the studied response. The optimized conditions for the answer was studied at 100 °C for evaporator temperature and 10 °C for the condenser temperature. The graph of "split ratio" showed that for the lowest flow feed (1 mL/min) and higher evaporator temperature (110 °C) was obtained in the largest fraction of distillate. It also used the study of the influence of evaporator temperature on the concentration of unsaturated compounds. The best operating conditions for temperature was 90 °C reached 82.21 % of unsaturated compounds. Elimination curves of the unsaturated compounds present in the distillate stream were obtained. The simulation results of the molecular distillation process of sunflower oil showed the concentration profiles for three different feed flow rates. The speed, temperature and thickness profiles of the liquid film were obtained. The speed of the film increases as the fluid flows through the walls of the evaporator, reaching a maximum on length of 0.075 m. The film thickness decreases on the route, since many compounds are volatilized. The result of the temperature profile had to be consistent with the literature reproduced, being constant after reaching the maximum operating temperature in the length of 0.15 m. This study allowed characterizing and focusing, through experimental analysis, unsaturated compounds and observing the sunflower oil´s behavior through process simulation.
Resumo:
Vegetable oils are characterized as important raw materials in the supplying of natural substances of interest pharmaceutical, food and cosmetic industry. Sunflower oil stands out for its important composition present in unsaturated fatty acids such as oleic acid (C18:1) and linoleic (C18:2), responsible for many health benefits. The main objective of this study is obtain enriched fractions in unsaturated compounds from refined sunflower oil. The oil used in this study was characterized by the determination of some properties, like iodine number, acid number and viscosity. A transesterification was done to transform the triglycerides into their corresponding methyl esters of fatty acids. These was submitted the molecular distillation process, for present as an efficient alternative to separation and purification of these substances, using high vacuum and low temperatures. Of the esters fractions that was obtained, were analyzed by gas chromatography. The experimental design technique was used to evaluate the influence of the temperature variation of evaporation and condensation system on the percentage obtained residue. The evaporator temperature proved to be the most influential variable on the studied response. The optimized conditions for the answer was studied at 100 °C for evaporator temperature and 10 °C for the condenser temperature. The graph of "split ratio" showed that for the lowest flow feed (1 mL/min) and higher evaporator temperature (110 °C) was obtained in the largest fraction of distillate. It also used the study of the influence of evaporator temperature on the concentration of unsaturated compounds. The best operating conditions for temperature was 90 °C reached 82.21 % of unsaturated compounds. Elimination curves of the unsaturated compounds present in the distillate stream were obtained. The simulation results of the molecular distillation process of sunflower oil showed the concentration profiles for three different feed flow rates. The speed, temperature and thickness profiles of the liquid film were obtained. The speed of the film increases as the fluid flows through the walls of the evaporator, reaching a maximum on length of 0.075 m. The film thickness decreases on the route, since many compounds are volatilized. The result of the temperature profile had to be consistent with the literature reproduced, being constant after reaching the maximum operating temperature in the length of 0.15 m. This study allowed characterizing and focusing, through experimental analysis, unsaturated compounds and observing the sunflower oil´s behavior through process simulation.
Resumo:
The hydrocycloning operation has a goal to separate solid-liquid suspensions and liquid-liquid emulsions through the centrifugal force action. Hydrocyclones are equipment with reduced size and used in both clarification and thickening. This device is used in many areas, like petrochemical and minerals process, and accumulate advantages like versatility and low cost of maintenance. However, the demand to improve the process and to reduce the costs has motivated several studies of equipment optimization. The filtering hydrocyclone is a non-conventional equipment developed at FEQUI/UFU with objective to improve the hydrocycloning separation efficiency. The purpose of this study is to evaluate the operating conditions of feed concentration and underflow diameter on the performance of a filtering geometry optimized to minimization of energy costs. The filtration effect was investigated through the comparison between the performance of the Optimized Filtering Hydrocyclone (HCOF) and the Optimized Concentrator Hydrocyclone (HCO). Because of the resemblance of hydrocyclones performance, the filtration did not represent significant effect on the performance of the HCOF. It was found that in this geometry the decrease of the variable underflow diameter was very favorable to thickening operation. The suspension concentration of quartzite at 1.0% of solids in volume was increased about 42 times when the 3 mm underflow diameter was used. The increase on the feed solid percentage was good for decreasing the energy spent, so that a minimum number of Euler of 730 was achieved at CVA = 10.0%v. However, a greater amount of solids in suspension leads to a lower efficiency of the equipment. Therefore, to minimize the underflow-to-throughput ratio and keep a high efficiency level, it is indicated to work with dilute suspension (CVA = 1.0%) and 3 mm underflow diameter (η = 67%). But if it is necessary to work with high feed concentration, the use of 5 mm underflow diameter provides a rise in the efficiency. The HCO hydrocyclone was compared to the traditional family of hydrocyclones Rietema and presented advantages like higher efficiency (34% higher in average) and lower energy costs (20% lower in average). Finally, the efficiency curves and project equation have been raised for the HCO hydrocyclone each with satisfactory adjust.
Resumo:
Atualmente a despoluição das águas, antes da sua descarga em meio hídrico, é considerada uma necessidade de elevada importância, sendo realizada em Estações de Tratamento de Águas Residuais (ETAR). Dependendo da origem e das características de cada afluente, as ETAR adotam diversos tipos de tratamento, adequando-os caso a caso, com o objetivo de conseguir uma elevada qualidade para o efluente final. O tipo de tratamento mais utilizado, e também o mais versátil, é o tratamento biológico por lamas ativadas. Neste contexto, o presente trabalho apresenta um estudo comparativo do processo de tratamento biológico por lamas ativadas, em operação em regime de arejamento prolongado, aplicado a três estações de tratamento de águas residuais, com características distintas no que se refere ao tipo de reator biológico utilizado, assim como, ao volume e à sazonalidade do caudal a tratar. As ETAR contempladas no estudo, nomeadamente, a ETAR do Juncal, a ETAR de Pedreiras e a ETAR de Fátima, localizam-se no distrito de Leiria e fazem parte do Saneamento Integrado dos Municípios do Lis (SIMLIS). A comparação do processo de tratamento das ETAR decorreu entre Outubro de 2013 e Junho de 2014, tendo-se baseado na monitorização dos reatores biológicos, no que se refere ao pH, potencial redox, OD, temperatura, concentração de SST e SSV, teste de sedimentabilidade, IVL, razão A/M e A/V, TRH, TRS, cor das lamas e microbiologia. Os valores obtidos permitiram concluir que, num contexto geral, as três ETAR apenas demonstraram um comportamento ideal relativamente aos valores de pH e potencial redox. Os valores de OD e temperatura mantiveram-se abaixo dos valores ideais para este tipo de tratamento; e a elevada concentração de SSV, nas ETAR de Fátima e de Pedreiras, e a baixa concentração de SSV, na ETAR de Juncal, impediram que a razão A/M, o teste de sedimentabilidade o IVL e o TRS cumprissem os valores ideais esperados. O incumprimento dos valores recomendados deve-se, muito provavelmente, ao facto das ETAR se encontrarem a operar abaixo da sua capacidade de utilização, no que respeita à população-equivalente a servir e ao volume de caudal afluente. Aparentemente as condições operacionais observadas durante o estudo não condicionaram o processo de tratamento biológico, uma vez que a qualidade do efluente tratado manteve sempre padrões elevados
Resumo:
O cluster é um fenômeno contemporâneo de grande importância, tendo sido cada vez mais estudado nos últimos anos em razão de sua importância estratégica para as empresas que o compõem, bem como para a região em que se localiza. Dessa forma, esta pesquisa objetiva identificar, analisar e classificar os fatores que contribuíram para o nascimento e manutenção de um cluster comercial especializado na distribuição varejista de produtos evangélicos na Rua Conde de Sarzedas (São Paulo – SP). Esta é uma pesquisa descritiva efetuada por meio de um levantamento de campo junto aos proprietários e gerentes das lojas varejistas do cluster comercial em estudo. Os principais fatores que contribuíram para o nascimento do cluster varejista foram: fundação da sede de uma grande igreja evangélica nos arredores, abertura de gravadora de discos evangélicos, participação de fiéis cantores, apoio da rádio e demanda dos produtos ofertados pelos fiéis. Já em relação à manutenção do cluster comercial, obteve-se os seguintes fatores pro lsores: divulgação boca a boca, fácil acesso, preços acessíveis, atendimento especializado, ações de marketing, crescimento da população evangélica local e de outras regiões, cooperação entre lojistas, eventos de promoção específicos, desenvolvimento da economia brasileira e acesso à internet.
Resumo:
O objetivo deste trabalho foi avaliar morfologicamente as membranas de PES preparadas a partir do uso de misturas de polivinilpirrolidona (PVP K-30 e K-90), visando ajustar as condições de síntese para a obtenção de uma membrana isenta de macroporos.
Resumo:
Ganoderma lucidum is a medicinal mushroom traditionally consumed in Asian countries that presents several beneficial effects already verified. Despite all studies about their bioactive compounds, the best cultivation media enrichment aiming to increase the production of these compounds is still uncertain. Besides, few studies are related to the performance of production animals. In order to test different cultivation media for G. lucidum mycelia, agricultural residues (solid state fermentation) and different sugars and aminoacids (in culture media with agar), were tested to evaluate G. lucidum mycelium growth. Supply of flour with G. lucidum mycelia obtained by solid state fermentation (wheat grain) for rabbits was also evaluated. Mycelium of G. lucidum developed very well in all agricultural residues, soybean hulls was the residue that presented higher growth rate and higher concentration of β-glucans. In the cultivation media experiment, G. lucidum also developed well, media that contained cellobiose and tyrosine, despite presenting lower growth rates and total growth within 10 days, produced mycelia with higher concentration of β-glucans and trolox equivalent antioxidant capacity (TEAC), respectively. Rabbits did not show any sign of intolerance to feed with different concentrations of flour with G. lucidum mycelium. All performance parameters and dressing percentages were adequate to the age at which they were slaughtered. Histological evaluation of organs presented alterations in renal cells (tubular and glomerulus), indicating a possible renal lesion according to the increase of flour with mycelium in feed. Histomorphometric evaluation showed increased vilous height in ileum and decreased vilous width of jejunus at 0.5% concentration, and decrease in crypt diameter according to the increase of concentration of flour with mycelium in feed. These results indicate the possibility of more studies regarding the aspects about cellobiose and tyrosine utilization for the production of bioactive compounds, and about toxicity of this mushroom mycelia, assuring the safety in supplying this product for animails.
Resumo:
The release of nitrogen compounds in water bodies can result in many environmental problems, so treat wastewater, such as sewage in order to remove not only organic matter but also nitrogen has been studied a few decades. From the above, the objective of this study was to evaluate the performance of a structured bed reactor, continuous flow, with recirculation, in removing organic matter and nitrogen present in wastewater under different cycles of intermittent aeration (AI) and to evaluate the influence of these cycles in the development of nitrifying bacteria (Oxidizing Bacteria Ammonia - BOA and Bacteria Oxidizing Nitrite - BON) and denitrifying (DESN) adhered (Support Material - MS) and suspension (Effluent - EF and sludge - LD). The reactor used has usable volume of 9.4 L. As support materials (MS) polyurethane foam was used, cut and fixed in PVC rods. 3 were worked aeration phases (AE) and non-aeration (AN) at different stage: Stage 1 (4 h EA / AN 2H); Stage 2 (2H EA / AN 1 h) and Phase 3 (2H EA / AN 2 h). During all hydraulic detention time phases was kept at 16 h and the effluent recirculated at a rate of 3 times the inflow. Were analyzed: pH, total alkalinity, temperature, chemical oxygen demand (COD), Biochemical Oxygen Demand (BOD), nitrogen Kjeldhl Total (NKT), ammonia-N-N-NH4+, nitrito-N-NO2+andnitrato-NO3-. The concentration of BOA, BON and DESN was determined using the number More Provável.gSSV-1 (NMP.gSSV-1). In phase 1 the percentage removal NTK N-NH4+ and NT was 76±10%, 70±21% and 67±10% respectively. In Phase 2 80±15% of removel NKT, 86±15% of N-NH4+ e 68±9% of removel NT e na Fase 3 de 58±20%, 72±28% and 41±6% of NKT, N-NH4+ of NT, respectively. The denitrification efficiency in stage 3 was over 70%, indicating that occurred in the reactor the process of simultaneous nitrification and denitrification (NDS). DQOT the removal percentages were 88 ± 4% in Phase 1, 94 ± 7 in Phase 2 and 90± 11% in Phase 3. The multivariate ANOVA applied to NMP.gSSV-1, it indicated that there was significant (F: 20,2, p <0,01) between the analyzed concentration of organisms AI in different cycles, but the differences between NMP.gSSV-1 depends not only isolated factors but of which means, and phase groups being analysis. From the results it is concluded that the working system is efficient in terms of nitrogen removal and organic matter, and that the stage with the highest availability of Dissolved Oxygen (DO) and C/N ratio (Step 2), was the one obtained the lower concentrations of organic matter effluents and N-NH4+. Hinted that there was a significant difference between the concentration (NMP.100mL-1) of the analyzed organizations (BOA, BON and DESN), but this difference does not depend on factors alone but of which means (MS, EF or LD), stages (1, 2 or 3) and groups (BOA, BON and DESN) is being considered.
Resumo:
O objetivo do presente trabalho foi analisar as características e os perfis lipídicos dos óleos brutos e refinados de rejeitos de carpa comum (Cyprinus carpio), obtidos através dos processos de ensilagem ácida e termomecânico de farinha de pescado. Também foram realizados o estudo da reação de alcoólise química do óleo de carpa e obtenção de concentrados de concentrados de ácidos graxos poliinsaturados (PUFAs), através da reação de complexação com uréia. O rendimento obtido em óleo bruto para ambos os processos foi em torno de 85% em relação ao óleo presente nas vísceras de carpa. Os óleos brutos obtidos através do processo de ensilagem e do processo termomecânico apresentaram diferenças significantivas (P < 0,05) para ácidos graxos livres, índice de peróxido, valor do ácido tiobarbitúrico e cor Lovibond. Entretanto, os óleos refinados obtidos por ambos os processos não apresentaram diferença significativa para a cor Lovibond, ácidos graxos livres e valores do ácido tiobarbitúrico. Os principais ácidos graxos identificados nos óleos bruto, branqueado e refinado de vísceras de carpa foram oléico, palmítico, palmitoléico, linoléico e linolênico constituindo aproximadamente 69,6% dos ácidos graxo totais do óleo refinado. A relação ω3/ω6 foi de aproximadamente 1,05 para o óleo refinado. Assim, o óleo refinado das vísceras de carpa pode ser considerado uma rica fonte de ácidos graxos essenciais do grupo ω3 e ω6. No estudo da reação de alcoólise química e obtenção dos concentrados de ácidos graxos poliinsaturados, foi realizada a comparação de três tratamentos para reação de alcoólise variando-se a concentração molar óleo:álcool (1:21, 1:27 e 1:39). Os tratamentos apresentaram diferenças significativas para as respostas rendimento em massa de ácidos graxos livres e índice de acidez. O maior rendimento para a reação de alcoólise foi utilizando a concentração molar de 1:39 (óleo:álcool). Na fração não complexada com uréia obteve-se aumento percentual de ácidos graxos insaturados e poliinsaturados de 31,9%, redução de saturados de 75%, e aumento do conteúdo dos ácidos graxos eicosapentaenóico e docosahexaenóico (EPA+DHA) de 85,3%. A fração não complexada com uréia pode ser considerada uma rica fonte de ácidos graxos poliinsaturados e insaturados com um total de 88,9% desses ácidos graxos.