52 research outputs found
Estudos sôbre a alimentação mineral do cafeeiro: XX. efeito da variação de pH no desenvolvimento e composição química do cafeeiro (Coffea arabica L., var. Mundo Nôvo) cultivado em solução nutritiva
Young coffee trees were grown in nutrient solution at different pH values, from pH 4,0 to pH 7,5 at 0,5 pH units of interval. After 140 days the plants were harvested and the main conclusions are the following: 1. The best range of pH for high, number of leaves fresh and dry weight of the plants were: pH 4,0 to pH 6,0. 2. There were a decrease in dry weight percentage of the leaves eith increase of the pH solution. 3. With the increase of the pH there was a decrease in macronutrients content in the plants. 4. At higher levels of pH there was a percentual decrease in N, P, Ca and S in the leaves. At pH 4,0 did not effect K content, bu there was a slight decrease in Mg content. 5. There was a linear relation between pH and the K+Ca+Mg/N+P+S ratio.Plantas jovens de Coffea arabica L., var. Mundo Nôvo foram cultivadas em solução nutritiva, sob o efeito de diferentes variações de pH (4,0 a 7,5) do substrato, a fim de se constatar o desenvolvimento e composição mineral. A melhor faixa de pH para o crescimento em altura, número de fôlhas, pêso da matéria fresca e sêca é de 4,0 a 6,0. A quantidade total de todos os macronutrientes absorvidos pelo cafeeiro diminui à medida que o pH se eleva
Electron impact ionization of 1-propanol
Experimental measurements of the cations created in electron impact ionization have been undertaken for the primary isomer of propanol using a Hidden Quadrupole Mass Spectrometer (EPIC 300), with a mass resolution of 1 amu. The mass spectra recorded at an incident electron energy of 70 eV reveals the relative probability of forming 50 different cations, by either direct ionization or dissociative ionization. Individual partial ionization cross sections (PICS) for 31 different cations were measured for the first time in this work, for the incident electron energy range from 10 to 100eV. Also, appearance energies (AEs) and Wannier exponents for the 16 most intense cations formed in electron collisions with 1-propanol are reported. Where possible, those results are compared to those from an earlier investigation. Total Ionization Cross Sections (TICS) were also obtained from the sum of the measured PICS, for nearly all cations measured, and are compared to relevant data reported in the literature. In addition, as a part of this study, theoretical TICS were calculated using the Binary-encounter Bethe (BEB) and independent atom model with screening corrected additivity rule (IAM - SCAR) methods. Good agreement between current measured and calculated TICSs and corresponding earlier results was typically found
Estudos sôbre a alimentação mineral do cafeeiro: XXI. efeito da adubação N, P, K e orgânica na composição mineral do grão e na qualidade da bebida. (2a. Nota)
In this second year of work, research was carried out concerning, the effect of N, P, K and organic fertilization on the mineral composition of the coffee bean and in the quality of the beverage. The material employed was obtained from a NxPxK, 2³ , factorial experiment with split plot (with and without organic matter). The test area is located in poor, deep and, sandy soil; Coffea Arabica L., Var. "Bourbon Vermelho" is the plant source. The main findings are as follows: a) N content in the bean was raised by the application of N in the soil. The use of K increases the level of K in the bean. The level of total P and soluble P was not affected by P fertilization. No treatment affected the S level in the bean. The level of the elements analysed was not affected significantly by the organic matter applied to the soil. b) Fruits collected in treatments where N and K were used gave significantly lower quality beverage. The quality of beverage wasn't affected by the organic matter. c) It was found a negative and significant (1%) correlation between N level in the bean and quality of beverage (r = -0,642). For K the correlation was found to be r - -0,449, significant at 10% of probability. No similar correlation was found with respect to P.O efeito da adubaçao NPK e da matéria orgânica na composição mineral do grão e na qualidade da bebida (prova de xícara) foi estudado. Verificou-se que a adubação fosfatada e o uso da matéria orgânica não influiram nas características mencionadas. A adubação nitrogenada e potássica aumentou o teor dos elementos correspondentes no grão e prejudicou pouco mas, significativamente a qualidade da bebida. Esses dados devem ser encarados com cautela e tidos apenas como preliminares
QUALIDADE TECNOLÓGICA DO CAFÉ ( Coffea arabica L.) PRÉ-PROCESSADO POR "VIA SECA" E "VIA ÚMIDA" AVALIADA POR MÉTODO QUÍMICO
Efeito da adição de sulfato de amônio sobre a produção de ácido succínico durante a fermentação alcoólica
Succinic acid production by yeasts during alcoholic fermentation of cane molasse supplemented with 25, 50 and 100 ppm of nitrogen in the form of ammonium sulfate was determined by gas-liquid chromatography. Ethanol production was not effected by the different levels of nitrogen, but there was a significant reduction in the content of succinic acid which was inversely related with the ammonium sulfate concentration in the medium.A produção de ácido succínico por leveduras durante a fermentação alcoólica de mosto de melaço suplementado com 25, 50 e 100 ppm de nitrogênio na forma de sulfato de amônio foi determinada por cromatografia em fase gasosa. A adição de nitrogênio amoniacal não afetou significativamente a produção de álcool etílico. Houve redução significativa no teor de ácido succínico com o aumento da quantidade de nitrogênio adicionada
Reproductive aspects of the oceanic whitetip shark, Carcharhinus longimanus (Elasmobranchii: Carcharhinidae), in the equatorial and southwestern Atlantic Ocean
The present study sought to study the reproductive biology of the oceanic whitetip shark, Carcharhinus longimanus, in the equatorial and southwestern Atlantic Ocean. A total of 234 specimens were collected as bycatch during pelagic longline fisheries targeting tunas and swordfish, between December 2003 and December 2010. The fishing area was located between latitudes 10N and 35S and longitudes 3E and 40W. Of the 234 individuals sampled, 118 were females (with sizes ranging from 81 to 227 cm TL, total length) and 116 males (ranging from 80 to 242 cm TL). The reproductive stages of the females were classed as immature, mature, preovulatory and pregnant, while males were divided into immature, maturing and mature. The size at maturity for females was estimated at 170.0 cm TL, while that for males was between 170.0 and 190.0 cm TL. Ovarian fecundity ranged from 1 to 10 follicles and uterine fecundity from 1 to 10 embryos. The reproductive cycle of this species is most likely biennial, with parturition occurring once every two years.info:eu-repo/semantics/publishedVersio
First Assessment of the Impacts of the COVID-19 Pandemic on Global Marine Recreational Fisheries
This work is the result of an international research effort to determine the main impacts of the COVID-19 pandemic on marine recreational fishing. Changes were assessed on (1) access to fishing, derived from lockdowns and other mobility restrictions; (2) ecosystems, because of alterations in fishing intensity and human presence; (3) the blue economy, derived from alterations in the investments and expenses of the fishers; and (4) society, in relation to variations in fishers’ health and well-being. For this, a consultation with experts from 16 countries was carried out, as well as an international online survey aimed at recreational fishers, that included specific questions designed to capture fishers’ heterogeneity in relation to behavior, skills and know-how, and vital involvement. Fishers’ participation in the online survey (5,998 recreational fishers in 15 countries) was promoted through a marketing campaign. The sensitivity of the fishers’ clustering procedure, based on the captured heterogeneity, was evaluated by SIMPER analysis and by generalized linear models. Results from the expert consultation highlighted a worldwide reduction in marine recreational fishing activity. Lower human-driven pressures are expected to generate some benefits for marine ecosystems. However, experts also identified high negative impacts on the blue economy, as well as on fisher health and well-being because of the loss of recreational fishing opportunities. Most (98%) of the fishers who participated in the online survey were identified as advanced, showing a much higher degree of commitment to recreational fishing than basic fishers (2%). Advanced fishers were, in general, more pessimistic about the impacts of COVID-19, reporting higher reductions in physical activity and fish consumption, as well as poorer quality of night rest, foul mood, and raised more concerns about their health status. Controlled and safe access to marine recreational fisheries during pandemics would provide benefits to the health and well-being of people and reduce negative socioeconomic impacts, especially for vulnerable social groups.Versión del edito
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