Pedro Almi - Academia.edu (original) (raw)
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Papers by Pedro Almi
Revista Brasileira De Fruticultura, 2002
RESUMO -A padronização da amostragem para a análise foliar em abacaxizeiros é importante para a o... more RESUMO -A padronização da amostragem para a análise foliar em abacaxizeiros é importante para a obtenção de resultados confiáveis. Neste aspecto, este trabalho visa a esclarecer a variação da composição mineral da folha de abacaxi, em plantas desenvolvidas em solo arenoso, sem irrigação. As folhas foram coletadas, limpas e divididas em 4 porções: aclorofilada, basal, mediana e apical. Após a secagem, as amostras foram pesadas, submetidas à digestão e analisadas pela metodologia adequada a cada nutriente. Uma grande variação no teor dos nutrientes foi encontrada ao longo da folha de abacaxi. Uma comparação confiável pode ser estabelecida entre as análises feitas com a folha inteira e a porção clorofilada da folha; o mesmo já não pode ser dito para a porção aclorofilada. Assim, este trabalho vem confirmar a necessidade da padronização da amostragem.
Journal of Organic Chemistry, 2006
The reaction of 1-(methylthio)acetone with different nitriles in the presence of triflic anhydrid... more The reaction of 1-(methylthio)acetone with different nitriles in the presence of triflic anhydride led to the one-pot formation of 2-substituted 5-methyl-4-methylthio-1,3-oxazoles in good yield. 1,2-and 1,4-Bisozaxolyl-substituted benzenes were obtained when the reaction was carried out using aromatic dinitriles. The methylthio group at the C4 position of the oxazole ring was easily removed with Raney nickel to form 2-substituted 5-methyl-1,3-oxazoles in good yields. 4-Methylsulfonyl derivatives were prepared by the oxidation of the MeS group with m-CPBA. The proposed mechanism for the formation of oxazoles involves an unstable 1-(methylthio)-2-oxopropyl triflate, which was detected from the low-temperature NMR spectra.
Revista Brasileira De Fruticultura, 2006
An experiment was conducted in a greenhouse with the objective to evaluate the quality of the fru... more An experiment was conducted in a greenhouse with the objective to evaluate the quality of the fruits of sweet passion fruit cultivated under deficiency of macronutrients and boron. Eight treatments with four replicates in a randomized complete block design were set up as follow: complete nutrient solution, -N, -P, -K, -Ca, -Mg, -S and -B. The experimental unity was a plastic box filled with 46 kg of river sand containing two plants irrigated with the nutrient solutions. All deficiencies reduced the fruit number per plant, and under Mg deficiency no flowers were formed. None of the nutrition deficiencies influence the mean weight of the fruits, the number of seeds per fruit, the length of the fruit and the percentage of juice. The deficiencies of N and P increased peel thickness and concentration in the fruit and they reduced seed percentage in the fruit. The deficiencies of N, P and K reduced the concentration of total soluble solids; K reduced the total titratable acidity; P reduced the pH and increased the vitamin C concentration, while the vitamin C concentration was reduced by the deficiencies of N, K and S. The characteristics of the fruits were not influenced by the deficiencies of Ca and B.
Revista Brasileira De Fruticultura, 2002
RESUMO -A padronização da amostragem para a análise foliar em abacaxizeiros é importante para a o... more RESUMO -A padronização da amostragem para a análise foliar em abacaxizeiros é importante para a obtenção de resultados confiáveis. Neste aspecto, este trabalho visa a esclarecer a variação da composição mineral da folha de abacaxi, em plantas desenvolvidas em solo arenoso, sem irrigação. As folhas foram coletadas, limpas e divididas em 4 porções: aclorofilada, basal, mediana e apical. Após a secagem, as amostras foram pesadas, submetidas à digestão e analisadas pela metodologia adequada a cada nutriente. Uma grande variação no teor dos nutrientes foi encontrada ao longo da folha de abacaxi. Uma comparação confiável pode ser estabelecida entre as análises feitas com a folha inteira e a porção clorofilada da folha; o mesmo já não pode ser dito para a porção aclorofilada. Assim, este trabalho vem confirmar a necessidade da padronização da amostragem.
Journal of Organic Chemistry, 2006
The reaction of 1-(methylthio)acetone with different nitriles in the presence of triflic anhydrid... more The reaction of 1-(methylthio)acetone with different nitriles in the presence of triflic anhydride led to the one-pot formation of 2-substituted 5-methyl-4-methylthio-1,3-oxazoles in good yield. 1,2-and 1,4-Bisozaxolyl-substituted benzenes were obtained when the reaction was carried out using aromatic dinitriles. The methylthio group at the C4 position of the oxazole ring was easily removed with Raney nickel to form 2-substituted 5-methyl-1,3-oxazoles in good yields. 4-Methylsulfonyl derivatives were prepared by the oxidation of the MeS group with m-CPBA. The proposed mechanism for the formation of oxazoles involves an unstable 1-(methylthio)-2-oxopropyl triflate, which was detected from the low-temperature NMR spectra.
Revista Brasileira De Fruticultura, 2006
An experiment was conducted in a greenhouse with the objective to evaluate the quality of the fru... more An experiment was conducted in a greenhouse with the objective to evaluate the quality of the fruits of sweet passion fruit cultivated under deficiency of macronutrients and boron. Eight treatments with four replicates in a randomized complete block design were set up as follow: complete nutrient solution, -N, -P, -K, -Ca, -Mg, -S and -B. The experimental unity was a plastic box filled with 46 kg of river sand containing two plants irrigated with the nutrient solutions. All deficiencies reduced the fruit number per plant, and under Mg deficiency no flowers were formed. None of the nutrition deficiencies influence the mean weight of the fruits, the number of seeds per fruit, the length of the fruit and the percentage of juice. The deficiencies of N and P increased peel thickness and concentration in the fruit and they reduced seed percentage in the fruit. The deficiencies of N, P and K reduced the concentration of total soluble solids; K reduced the total titratable acidity; P reduced the pH and increased the vitamin C concentration, while the vitamin C concentration was reduced by the deficiencies of N, K and S. The characteristics of the fruits were not influenced by the deficiencies of Ca and B.