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Search Results: 1 - 10 of 1855 matches for " Raphael;Wutke "
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Restaura??o do solo para a cultura de cana-de-a?úcar: III - Período 1958-61 e considera??es gerais
Wutke, Ant?nio Carlos Pimentel;Alvarez, Raphael;
Bragantia , 1968, DOI: 10.1590/S0006-87051968000100018
Abstract: this paper reports the data obtained in the third period of an experiment which was started in 1954, to study the recovering for sugar cane culture of an original low fertility and impoverished soil (humic red-yellow latosol) . at the same time with the results of the two harvestings of this third planting one discusses the soil productivity and fertility variations which had occurred up to the first planting. in a randomized blocks design eight treatments with four replications were compared. they are as follows: a) control; b) p + lime + leguminous cover crop; c) pk + cover crop; d) pk + lime + cover crop; e) npk; f) npk ++ lime; g) npk + cover crop; h) npk + lime + cover crop. in this period the cover crop still used was the sun hemp (crotalaria junceal.) and the sugar cane variety planted was cb 41/76. in the planting time the fertilization applied was at the rates of 90-80-120 kg per hectare of n, p2o5 and k2o respectively and as ammonium sulfate, plain superphosphate and potassium chloride. after the first harvesting other applications of nitrogen and potassium were made, at the rates of 60 kg and 90 kg per hectare respectively, using the same sources of fertilizers in top-dressing application. the yields of sugar cane obtained in this period showed appreciable effects due to lime and potassium and a considerable increase in soil productivity as compared with the data corresponding to the other ones. this result is attributed to the soil fertility increase, on account of favorable variations in soil acidity and ca, mg and po4 levels, as shown by chemical analyses. in spite of the leguminous cover crop usage and chemical fertilizations, no increase in carbon, nitrogen and potassium soil levels were detected.
Aduba??o da cana-de-a?úcar: XV - experimentos com micronutrientes nas regi?es canavieiras do estado de S?o Paulo
Alvarez, Raphael;Wutke, Ant?nio Carlos Pimentel;Arruda, Hermano Vaz de;Godoy Júnior, Gentil;
Bragantia , 1979, DOI: 10.1590/S0006-87051979000100003
Abstract: the results obtained with twenty three experiments on the application of micronutrients to sugar cane are presented in this paper. the experiments were installed to evaluate the possible occurrence of micronutrient deficiencies in soils of s?o paulo state that had been more intensively cultivated with this crop. therefore, in the localization of the field plots care was taken securing a large variation of conditions, especially those of the soil that are related to availability of micronutrients. the experiments were planted in randomized block designs with four replications. the treatments were as follows: 1. 000 (general control); 2. npk (control); 3. npk + fe; 4. npk + b; 5. npk + cu; 6. npk + zn; 7. npk + mn; 8. npk + mo. the nitrogen, phosphorus and potassium were applied as ammonium sulfate, superphosphate and potassium chloride, at the rates of 80kg/n, l00kg/p2o5 and 120kg/k2o per hectare. the micronutrients were applied in the furrows in addition to the basic fertilization: iron, manganese, copper and zinc, as sulfates; boron, as borax, and molybdenum as ammonium molybdate. in accordance with the purpose of the study the soils of the experiments showed great variation in the characteristics that are involved with the micronutrients availability, as the ph and the original fertility level. in spite of this, in only one of the experiments the micronutrients, cooper and molybdenum in the case, gave yield increases; even so, the responses were not clearly related to the soil characteristics. the results indicate that problems concerning micronutrient deficiencies are not to be expected in the normal conditions of the sugar cane culture in s?o paulo state, thus, the possible occurrences of such anomalies, until now, must be related to fortuitous events.
Restaura??o de solo para a cultura da cana-de-a?úcar: II - Período 1956-58
Wutke, Ant?nio Carlos Pimentel;Alvarez, Raphael;Gargantini, Hermano;Arruda, Hermano Vaz de;
Bragantia , 1960, DOI: 10.1590/S0006-87051960000100043
Abstract: the experiment reported in this paper was started in 1954. its object was to study the effect of various treatments on the restoration of productivity in a tract of impoverished land (glacial formation), located at the usina ester, cosmópolis county. eight treatments with four replications are being compared in randomized blocks. they are as follows: (a) control, (b) p + lime + leguminous cover crop; (c) pk + cover crop; (d) pk + lime + cover crop; (e) npk; (f) npk + lime; (g) npk + cover crop, (h) npk + lime + cover crop. ammonium sulfate, plain superphosphate, and pottassiu chloride were applied at the rates of 90, 120, and 90 kg per hectare of n, p2o5, and k2o, respectively. the cover crop used was the sun hemp (crotalaria juncea l.). the sugar cane variety planted was the c. b. 40/69. the results obtained in the first harvest of this second planting were as follows: (a) all plots receiving fertilizers gave higher yields than the control; (b) the highest yields were given by the plots receiving pk + lime + cover crop, npk + lime + cover crop, and npk + lime. the results obtained so far indicate that the best treatments improved the soil productivity, whereas there is some evidence of a decrease in productivity induced by others.
Aduba??o da cana-de-acúcar: XIV. Aduba??o NPK em latossolo roxo
Alvarez, Raphael;Wutke, Ant?nio Carlos Pimentel;Arruda, Hermano Vaz de;Van Raij, Bernardo;Gomes, Ant?nio Carlos;Zink, Frederico;
Bragantia , 1991, DOI: 10.1590/S0006-87051991000200014
Abstract: nineteen 33 npk factorial experiments with sugar cane were carried out in 1958/59 on dusky red latosol soils of various sugar plant owned lands, in the state of s?o paulo, brazil. the amounts of nutrients applied corresponded to: 0, 90 and 180 kg/ha of n; 0, 80 and 160kg/ha of p205; and 0, 100 and 200kg/ha of k2o. the experiments were separated in two types of areas, based on former soil use: one group in areas where sugar cane was cultivated over ten years, and the other group in areas where which sugar cane had never been cultivated. the results were in accordance with former management, indicating residual effect of phosphorus applications and potassium depletion on the areas former cultivated with sugar cane. however, responses to nitrogen could not be related to former soil usage. responses of sugar cane to nitrogen were related to soil organic matter (r = 0.695**) and to phosphorus with resin extractable p (r = 0.709**), but the response to potassium fertilizer was not related to soil k (r = 0.284 n.s). with adjusted response functions, the optimal economical amount of nutrients were shown to be in general, higher than the current recommendations. yield increases promoted by npk were directly related to the maximum economic yield (r = 0.773**).
Cross-Correlation of Station-to-Station Free Surface Elevation Time Series for Breaking Water Waves  [PDF]
Raphael Mukaro
Applied Mathematics (AM) , 2018, DOI: 10.4236/am.2018.92010
Abstract:
Free surface elevation time series of breaking water waves were measured in a laboratory flume. This was done in order to analyze changes in wave characteristics as the waves propagated from deep water to the shore. A pair of parallel- wire capacitive wave gages was used to simultaneously measure free surface elevations at different positions along the flume. One gage was kept fixed near the wave generator to provide a reference while the other was moved in steps of 0.1 m in the vicinity of the break point. Data from these two wave gages measured at the same time constitute station-to-station free surface elevation time series. Fast Fourier Transform (FFT) based cross-correlation techniques were employed to determine the time lag between each pair of the time series. The time lag was used to compute the phase shift between the reference wave gage and that at various points along the flume. Phase differences between two points spaced 0.1 m apart were used to calculate local mean wave phase velocity for a point that lies in the middle. Results show that moving from deep water to shallow water, the measured mean phase velocity decreases almost linearly from about 1.75 m/s to about 1.50 m/s at the break point. Just after the break point, wave phase velocity abruptly increases to a maximum value of 1.87 m/s observed at a position 30 cm downstream of the break point. Thereafter, the phase velocity decreases, reaching a minimum of about 1.30 m/s.
Optimization of an Ammonia Synthesis Converter  [PDF]
Jackson Gunorubon Akpa, Nwokoma Raphael Raphael
World Journal of Engineering and Technology (WJET) , 2014, DOI: 10.4236/wjet.2014.24032
Abstract: A scheme that optimizes the converter of an ammonia synthesis plant to determine optimal inlet temperatures of the catalyst beds has been developed. The optimizer maximizes an objective function—The fractional conversion of nitrogen on the four catalyst beds of the converter subject to variation of the inlet temperature to each catalyst bed. An iterative procedure was used to update the initial values of inlet temperature thus ensuring accurate results and quick convergence. Converter model results obtained with optimized operating conditions showed significant increase in fractional conversion of 42.38% (from 0.1949 to 0.2586), increased rate of reaction evident in a 13.18% (0.5317 to 0.4616) and 23.84% (0.1946 to 0.1482) reduction in reactants (hydrogen and nitrogen) concentration respectively and a 56.48% increase (from 0.1181 to 0.1838) in ammonia concentration at the end of the fourth catalyst bed compared to results obtained with industrial operating conditions.
Discrimina??o entre lotes de sementes de gr?o-de-bico mediante teste de envelhecimento artificial
Maeda, Jocely Andreuccetti;Wutke, Elaine Bahia;
Bragantia , 1996, DOI: 10.1590/S0006-87051996000100015
Abstract: eleven chickpea seed lots were subjected to the artificial aging test at 42°c and 100% relative humidity for periods of 0, 24, 48, 72 and 96 hours. the objective was to determine the exposure time that best discriminate the lots for the germination response after aging. the 96 hours period was too long, and the 48 hours period was inefficient; 24 and 72 hours were both similar in the lots classifying as to the seeds vigor levels. however, the 72 hours period was the best to discriminate lots whose germination values were over than 82%.
Fixa??o do nitrogênio do ar pelas bactérias que vivem associadas às raízes do feij?o de porco e do feij?o baiano
Gargantini, Hermano;Wutke, Ant?nio Carlos Pimentel;
Bragantia , 1960, DOI: 10.1590/S0006-87051960000100040
Abstract: the determination of the nitrogen fixed from the air by bacteria in association with sword bean (canavalia ensiformis d. c.) and cowpea (feij?o baiano) (vigna sinensis (l.) savi) was the main purpose of this work. the two leguminous plants were sown in mitscherlich pots filled with 6 kg of "terra-roxa-misturada" soil, collected at the depth of 20 cm in the central experiment station, instituto agron?mico, campinas county. the following treatments with three replications were compared: 1) check; 2) npk; 3) npk + limestone; 4) npk + inoculant; 5) npk + limestone + inoculant; 6) pk + limestone; 7) pk + limestone + inoculant. the amount of limestone was calculated to raise the ph to 6.5 and the base saturation of the sail to 70%. the fertilizer applications for n, p2o5,. and k2o were 2.0 g, 2.2 g and 3.0 g respectively, as solutions of nh4no3, k2hp04 and kcl. harvesting was done at the beginning of blooming-time by cutting the plants even with the ground. later, both the aerial parts, as well as the roots, were weighed fresh and after drying at 60° c. nitrogen determination by the kjeldahl method of these two fractions, aerial parts and roots, were mode after drying. the soil from those pots without nitrogen fertilizer were submitted to the same analysis for comparison with the initial level of this element in the soil. the data obtained indicate that the two leguminous plants showed a good nitrogen fixation capacity and that the feij?o baiano was more effective. the amounts of nitrogen fixed in pots that received the best treatments corresponded to 48.5 kg per hectare for the sword bean and 73.0 kg for the "feij?o baiano". from this point of view both leguminous plants were satisfactory to be employed as green manure.
Sponsor-investigator-relationship: challenges, recent regulatory developments and future legislative trends  [PDF]
Raphael Richard Ciuman
Health (Health) , 2011, DOI: 10.4236/health.2011.312128
Abstract: Correct definition and management of sponsor- investigator relationship is of central importance for planing and executing clinical trials. During the last decade, there have been numerous modifications of guidelindes, international and national legislations and regulations. This implicated various alterations and shifts of essential responsibilities and tasks relating to the investigator, sponsor or sponsor-investigator what raised financial, clinical and ethical issues. First experiences with these new regulations and legislations are discussed together with international differences and their impacts on clinical trials. Regarding non-commercial trials and institutional sponsorship, there are still open organizational and legal questions after national implementation of the Europeam Clinical Trials Directive in 2004, although various approaches have been suggested in recent years in Europe. Current trends and controversies are discussed as well. A literature review was performed summarizing recent experiences with current legislations and risen controversies of these new legislations showing impact on future trends.
Corrosion Studies on Stainless Steel (FE6956) in Hydrochloric Acid Solution  [PDF]
Raphael Shadai Oguike
Advances in Materials Physics and Chemistry (AMPC) , 2014, DOI: 10.4236/ampc.2014.48018
Abstract: The effect of hydrochloric acid concentration on stainless steel (Fe6956) at temperature range 303 - 333 ± 1 K has been studied using weight loss, thermometric and electrochemical polarization techniques. The corrosion rate of the stainless steel was found to be dependent on both temperature variation and acid concentration. The potentiostatic study showed that the active passive transition depends strongly on acid concentration while the weight loss measurements revealed that 2 M HCl at temperature 333 K had an appreciable corrosion rate which corresponds to 14.04 × 10﹣3 reaction number (RN) got from thermometric monitoring. Arrhenius equation and transition state theory were used to calculate kinetic and thermodynamic parameter such as Ea, ΔH* and ΔS*. Results obtained showed that corrosion reaction of Fe6956 in HCl is spontaneous and there is good agreement between the data got from the techniques employed.
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