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1.
Sci. agric ; 77(5): e20190027, 2020. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1497880

Resumo

Ethyl carbamate (EC) (NH2COOCH2CH3) is found in cachaça, and its presence in the beverage is conspicuous for its toxicity. Copper, the metal of choice used in the construction of stills, is also considered a beverage contaminant and is often related to the presence of EC in beverages. The study aimed to monitor the quality of cachaça by measuring the presence of copper and EC, and comparing the influences of sugarcane cultivation systems on the concentration of these contaminants. The varieties, RB 867515, RB 962869 and RB 85553, were cultivated under the following management systems: planting without fertilization; organic planting; and conventional planting. For cultivation, a completely randomized design in a factorial scheme of 3 varieties × 3 managements was used as experimental planning, in 4 replications. The concentrations of copper and EC in beverages were evaluated and submitted to univariate analysis of variance (p ≤ 0.05). The organic and conventional systems presented no significant variations in copper content, both of which are recommended for the planting of sugarcane as raw material for cachaça. From amongst the varieties evaluated, RB966928 presented the lowest concentrations of copper for the organic and conventional systems, and was the most recommended for the production of cachaça. To evaluate the EC concentration (μg L–1) in the cachaças produced, all beverages were considered in accordance with national legislation. Significant differences were observed between them, but the conventional and organic systems are favored for deployment in the cultivation of sugarcane as the raw material of cachaça. The same applies to the RB966928, RB867515 and RB855453 varieties.


Assuntos
Bebidas Alcoólicas/análise , Cobre/isolamento & purificação , Contaminantes Químicos em Alimentos , Saccharum , Uretana/isolamento & purificação , Controle e Fiscalização de Alimentos e Bebidas
2.
Sci. agric. ; 77(5): e20190027, 2020. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-24804

Resumo

Ethyl carbamate (EC) (NH2COOCH2CH3) is found in cachaça, and its presence in the beverage is conspicuous for its toxicity. Copper, the metal of choice used in the construction of stills, is also considered a beverage contaminant and is often related to the presence of EC in beverages. The study aimed to monitor the quality of cachaça by measuring the presence of copper and EC, and comparing the influences of sugarcane cultivation systems on the concentration of these contaminants. The varieties, RB 867515, RB 962869 and RB 85553, were cultivated under the following management systems: planting without fertilization; organic planting; and conventional planting. For cultivation, a completely randomized design in a factorial scheme of 3 varieties × 3 managements was used as experimental planning, in 4 replications. The concentrations of copper and EC in beverages were evaluated and submitted to univariate analysis of variance (p ≤ 0.05). The organic and conventional systems presented no significant variations in copper content, both of which are recommended for the planting of sugarcane as raw material for cachaça. From amongst the varieties evaluated, RB966928 presented the lowest concentrations of copper for the organic and conventional systems, and was the most recommended for the production of cachaça. To evaluate the EC concentration (μg L–1) in the cachaças produced, all beverages were considered in accordance with national legislation. Significant differences were observed between them, but the conventional and organic systems are favored for deployment in the cultivation of sugarcane as the raw material of cachaça. The same applies to the RB966928, RB867515 and RB855453 varieties.(AU)


Assuntos
Saccharum , Contaminantes Químicos em Alimentos , Bebidas Alcoólicas/análise , Uretana/isolamento & purificação , Cobre/isolamento & purificação , Controle e Fiscalização de Alimentos e Bebidas
3.
Sci. agric ; 77(6): e20180384, 2020. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1497897

Resumo

The utilization of insoluble sources of micronutrients as concentrated suspensions (CSs) is increasing in Brazilian agriculture; however, much information regarding the physicochemical characterization of these products is required to demonstrate the absorption behavior by plant leaves. This study aimed to characterize the CSs available on the Brazilian market to support their potential use as foliar fertilizers. We selected five CSs containing Mn, five CSs containing Zn and three CSs containing Cu from five different companies. In each product, the mean particle size was evaluated by dynamic light scattering (DLS), the particle shape and size were evaluated by scanning electron microscopy (SEM), the aggregation degree was determined by the zeta potential and the heavy metal contents were determined by acid digestion followed by reading on ICP-OES. The mean hydrodynamic diameter of fertilizers containing Cu, Mn and Zn was 315 ± 55, 378 ± 184 and 435 ± 107 nm, respectively. The zeta potential varied from –20 to –30 mV, indicating potential particle aggregation and formation of higher structures. SEM images indicated great variation in the size and shape of the particles in each product. All products exhibited concentrations of toxic elements within the legislation thresholds. The average particle size of CSs currently marketable in Brazil does not allow their classification as nanomaterials (< 100 nm). Therefore, their foliar absorption is unlikely, once the particle size is higher than the exclusion limit observed for stomata and cuticle pathways, as well as the nutrient content as ions is low according to the solubility constant.


Assuntos
Fertilizantes/análise , Fertilizantes/toxicidade , Cobre/isolamento & purificação , Manganês/isolamento & purificação , Zinco/isolamento & purificação
4.
Sci. agric. ; 77(6): e20180384, 2020. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-24819

Resumo

The utilization of insoluble sources of micronutrients as concentrated suspensions (CSs) is increasing in Brazilian agriculture; however, much information regarding the physicochemical characterization of these products is required to demonstrate the absorption behavior by plant leaves. This study aimed to characterize the CSs available on the Brazilian market to support their potential use as foliar fertilizers. We selected five CSs containing Mn, five CSs containing Zn and three CSs containing Cu from five different companies. In each product, the mean particle size was evaluated by dynamic light scattering (DLS), the particle shape and size were evaluated by scanning electron microscopy (SEM), the aggregation degree was determined by the zeta potential and the heavy metal contents were determined by acid digestion followed by reading on ICP-OES. The mean hydrodynamic diameter of fertilizers containing Cu, Mn and Zn was 315 ± 55, 378 ± 184 and 435 ± 107 nm, respectively. The zeta potential varied from –20 to –30 mV, indicating potential particle aggregation and formation of higher structures. SEM images indicated great variation in the size and shape of the particles in each product. All products exhibited concentrations of toxic elements within the legislation thresholds. The average particle size of CSs currently marketable in Brazil does not allow their classification as nanomaterials (< 100 nm). Therefore, their foliar absorption is unlikely, once the particle size is higher than the exclusion limit observed for stomata and cuticle pathways, as well as the nutrient content as ions is low according to the solubility constant.(AU)


Assuntos
Fertilizantes/toxicidade , Fertilizantes/análise , Zinco/isolamento & purificação , Cobre/isolamento & purificação , Manganês/isolamento & purificação
5.
Pesqui. vet. bras ; 35(9): 767-774, set. 2015. tab, graf
Artigo em Português | VETINDEX | ID: vti-9642

Resumo

Para a determinação dos teores de cobre e de seus antagonistas, foram utilizadas 160 amostras de soro e de fígados, de caprinos e ovinos enviados ao matadouro municipal de Petrolina. As amostras de fígado e soro foram correlacionadas para o mesmo animal, a fim de evitar erros na obtenção dos dados. No soro a atividade da ceruloplasmina foi determinada por método colorimétrico. Para a determinação dos minerais, as amostras foram diluídas de seis a vinte vezes com água Milli-Q. Para determinação das concentrações dos elementos minerais no fígado, as amostras foram digeridas até que se obtivesse uma solução que mantivesse os minerais da amostra inicial e que fosse totalmente liquida, sem a presença de partículas sólidas que pudessem obstruir os capilares de sucção do espectrômetro e assim impedir as leituras das amostras. As concentrações de cobre, molibdênio, ferro e zinco foram determinadas através de espectrometria óptica por emissão de plasma (ICP). Desta forma, foi conduzido o experimento objetivando determinar a ocorrência e distribuição da carência de cobre no território do sertão do vale do rio São Francisco em Pernambuco. Foi observado que não houve carência de cobre nesta região do estado de Pernambuco, quando se avaliou os níveis médios de cobre hepático,. Os níveis de zinco estavam dentro de um padrão de normalidade, enquanto que os níveis de ferro foram mais elevados em ovinos, e os níveis de molibdênio mais reduzidos em caprinos. Verificou-se também que a atividade de ceruloplasmina foi um indicador dos níveis séricos de cobre.(AU)


For the determination of copper concentration and its antagonists, 160 serum and liver samples were used, from goat and sheep sent to the municipal slaughterhouse of Petrolina. The samples were correlated with the same animal, in order to prevent errors in data collection. Serum ceruloplasmin activity was determined by colorimetric method. For determination of minerals, the samples were diluted six to twenty times with Milli-Q water. For determining concentrations of mineral elements in the liver, the samples were digested until achieving a solution that maintained the initial sample and minerals totally liquid, without the presence of solid particles which could clog the capillary suction of the spectrometer and prevent reading of samples. The concentrations of copper, molybdenum, iron and zinc were determined by optical emission spectrometry (ICP). Thus, the experiment was conducted to determine the occurrence and distribution of copper deficiency in the San Francisco valley of Pernambuco. No copper deficiency was revealed in this region of the state of Pernambuco, when the mean levels of hepatic copper were evaluated. Zinc levels were within a normal range, whereas iron levels were higher in sheep, and lower levels of molybdenum in goats. It was also found that the activity of ceruloplasmin was an indicator of serum copper.(AU)


Assuntos
Animais , Deficiência de Minerais , Ovinos/crescimento & desenvolvimento , Ceruloplasmina/administração & dosagem , Cobre/isolamento & purificação , Ruminantes/crescimento & desenvolvimento , Molibdênio/isolamento & purificação , Deficiência de Zinco , Deficiências de Ferro/diagnóstico
6.
Pirassununga; s.n; 14/12/2012. None p.
Tese em Português | VETINDEX | ID: biblio-1505199

Resumo

A pesquisa visou avaliar a metodologia do projeto Tree Vis para determinar a nutrição de ferro, boro, zinco e cobre em plantas de milho submetidas a doses desses nutrientes. Foram utilizados tratamentos constituídos pela omissão, 1/5, 2/5 e a dose completa dos elementos com quatro repetições em cada fase de coleta, sendo essas V4, V7 e R1. Os experimentos foram realizados em casa de vegetação, em cultivo hidropônico, conduzidos em vasos com solução nutritiva. Foi determinada a produção de massa seca da parte aérea e do sistema radicular, além da determinação dos teores dos nutrientes nas folhas indicativas dos estádios fenológicos de cada época de coleta. Em cada estádio foram coletadas imagens das folhas indicativas e novas através de um scanner para as análises de visão artificial. As doses crescentes dos nutrientes promoveram maior produção de massa seca na parte aérea e nas raízes e reduziram a produção quando utilizada a dose máxima do nutriente. O sistema de visão artificial mostrou-se promissor na identificação de deficiência de ferro com 77,5% de acerto, boro com 81,7% de acerto, zinco com 81,0% e cobre com 57,2 % de acerto, tendo identificado as com boa confiabilidade


The research aimed to evaluate the methodology of the Pr oject Tree Vis for determining nutrition iron, boron, zinc and copper in maize plants subjected to doses of these nutrients. Treatments used were made by omission, 1/5, 2/5 and the full dose of the elements with four replicates at each stage of collection, these are V4, V7 and R1. The experiments ware conducted in a greenhouse in hydroponics, conducted in pots with nutrient solution. Was determined the dry mass production of the aerial part and roots, besides the determ ination of nutritional content in the leaves indicative of phenological stages of each harvest time. At each stage were collected images of indicative and new leaves through with a scanner for the analyzes of artificial vision. The increasing doses of nutr ients promoted higher dry mass production in the aerial part and roots and reduced the production when using the highest dose of the nutrient. The artificial vision system showed promise in identifying of deficiency of iron with 77.5% accuracy, of boron with 81.7% of correct, of zinc with 81.0% accuracy and copper with 57.2% accuracy, with a good reliability in the identifi


Assuntos
Boro/isolamento & purificação , Cobre/isolamento & purificação , Ferro/isolamento & purificação , Zea mays/química , Zinco/isolamento & purificação , Fenômenos Fisiológicos Vegetais
7.
Pirassununga; s.n; 14/12/2012. None p.
Tese em Português | VETTESES | ID: vtt-6761

Resumo

A pesquisa visou avaliar a metodologia do projeto Tree Vis para determinar a nutrição de ferro, boro, zinco e cobre em plantas de milho submetidas a doses desses nutrientes. Foram utilizados tratamentos constituídos pela omissão, 1/5, 2/5 e a dose completa dos elementos com quatro repetições em cada fase de coleta, sendo essas V4, V7 e R1. Os experimentos foram realizados em casa de vegetação, em cultivo hidropônico, conduzidos em vasos com solução nutritiva. Foi determinada a produção de massa seca da parte aérea e do sistema radicular, além da determinação dos teores dos nutrientes nas folhas indicativas dos estádios fenológicos de cada época de coleta. Em cada estádio foram coletadas imagens das folhas indicativas e novas através de um scanner para as análises de visão artificial. As doses crescentes dos nutrientes promoveram maior produção de massa seca na parte aérea e nas raízes e reduziram a produção quando utilizada a dose máxima do nutriente. O sistema de visão artificial mostrou-se promissor na identificação de deficiência de ferro com 77,5% de acerto, boro com 81,7% de acerto, zinco com 81,0% e cobre com 57,2 % de acerto, tendo identificado as com boa confiabilidade (AU)


The research aimed to evaluate the methodology of the Pr oject Tree Vis for determining nutrition iron, boron, zinc and copper in maize plants subjected to doses of these nutrients. Treatments used were made by omission, 1/5, 2/5 and the full dose of the elements with four replicates at each stage of collection, these are V4, V7 and R1. The experiments ware conducted in a greenhouse in hydroponics, conducted in pots with nutrient solution. Was determined the dry mass production of the aerial part and roots, besides the determ ination of nutritional content in the leaves indicative of phenological stages of each harvest time. At each stage were collected images of indicative and new leaves through with a scanner for the analyzes of artificial vision. The increasing doses of nutr ients promoted higher dry mass production in the aerial part and roots and reduced the production when using the highest dose of the nutrient. The artificial vision system showed promise in identifying of deficiency of iron with 77.5% accuracy, of boron with 81.7% of correct, of zinc with 81.0% accuracy and copper with 57.2% accuracy, with a good reliability in the identifi (AU)


Assuntos
Zea mays/química , Ferro/isolamento & purificação , Boro/isolamento & purificação , Zinco/isolamento & purificação , Cobre/isolamento & purificação , Fenômenos Fisiológicos Vegetais
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