1000 resultados para Automatization, VI coding, calibration, hot wire anemometry
Resumo:
Uma nova espécie de Prestonia R. Br., endêmica dos estados do Acre e Amazonas, Brasil, é descrita e ilustrada e se discute as relações com taxas relacionadas.
Resumo:
The chapter presents a theoretical proposal of three analytical models of Adult Learning and Education (ALE) policies. Some analytical categories and the corresponding dimensions are organised according to the ALE rationale which is typical of each social policy model. Historical, cultural and educational features are mentioned in connexion with the different policy models and its interpretative capacity to making sense of policies and practices implemented in Germany, Portugal and Sweden. !e analysis includes the states of the art and the official representations of ALE produced by the respective national authorities through national reports which were presented to CONFINTEA VI (2009).
Resumo:
This paper describes the trigger and offline reconstruction, identification and energy calibration algorithms for hadronic decays of tau leptons employed for the data collected from pp collisions in 2012 with the ATLAS detector at the LHC center-of-mass energy s√ = 8 TeV. The performance of these algorithms is measured in most cases with Z decays to tau leptons using the full 2012 dataset, corresponding to an integrated luminosity of 20.3 fb−1. An uncertainty on the offline reconstructed tau energy scale of 2% to 4%, depending on transverse energy and pseudorapidity, is achieved using two independent methods. The offline tau identification efficiency is measured with a precision of 2.5% for hadronically decaying tau leptons with one associated track, and of 4% for the case of three associated tracks, inclusive in pseudorapidity and for a visible transverse energy greater than 20 GeV. For hadronic tau lepton decays selected by offline algorithms, the tau trigger identification efficiency is measured with a precision of 2% to 8%, depending on the transverse energy. The performance of the tau algorithms, both offline and at the trigger level, is found to be stable with respect to the number of concurrent proton--proton interactions and has supported a variety of physics results using hadronically decaying tau leptons at ATLAS.
Resumo:
Na Amazônia o cromo é empregado principalmente na indústria de couro e de madeira, sendo responsável por vários problemas de saúde porque é tóxico para os seres vivos. A remoção de cromo de efluentes industriais é feita por meio de diversos processos como a adsorção. Este trabalho mostra os resultados da adsorção de Cr(VI) por carvão ativado granular comercial (CAG) como adsorvente de soluções diluídas empregando um sistema de adsorção batelada com controle de pH. Os grupos funcionais da superfície do CAG foram determinados pelo método de Boehm. Além disso, o efeito do pH na adsorção de Cr(VI), o equilíbrio e a cinética de adsorção foram estudados nas condições experimentais (pH = 6, MA = 6g, tempo de adsorção 90min.). Na superfície do CAG, os grupos carboxílicos foram determinados em maior concentração (MAS=0,43 mmol/gCAG), estes, presentes em concentrações elevadas aumentam a adsorção do metal, principalmente em valores de pH ácidos. A capacidade de adsorção é dependente do pH da solução, devido a sua influência nas propriedades de superfície do CAG e nas diferentes formas iônicas das soluções de Cr(VI). Os dados de equilíbrio da adsorção foram ajustados satisfatoriamente pela isoterma de Langmuir (R²=0,988), tipo favorável. A partir da cinética de adsorção a 5mg/L e 20mg/L, os resultados obtidos foram compatíveis com o valor limite preconizado na legislação nacional (Res. nº 357/05). Portanto, para o sistema experimental utilizando CAG foi eficiente na remoção de Cr(VI) a partir de correntes líquidas contendo baixas concentrações do metal.
Resumo:
Dissertação de mestrado em Engenharia de Materiais
Resumo:
Land cover changes over time as a result of human activity. Nowadays deforestation may be considered one of the main environmental problems. The objective of this study was to identify and characterize changes to forest cover in Venezuela between 2005-2010. Two maps of deforestation hot spots were generated on the basis of MODIS data, one using digital techniques and the other by means of direct visual interpretation by experts. These maps were validated against Landsat ETM+ images. The accuracy of the map obtained digitally was estimated by means of a confusion matrix. The overall accuracy of the maps obtained digitally was 92.5%. Expert opinions regarding the hot spots permitted the causes of deforestation to be identified. The main processes of deforestation were concentrated to the north of the Orinoco River, where 8.63% of the country's forests are located. In this region, some places registered an average annual forest change rate of between 0.72% and 2.95%, above the forest change rate for the country as a whole (0.61%). The main causes of deforestation for the period evaluated were agricultural and livestock activities (47.9%), particularly family subsistence farming and extensive farming which were carried out in 94% of the identified areas.
Resumo:
The barrier effect and the performance of an organic–inorganic hybrid (OIH) sol–gel coating are highlydependent on the coating deposition method as well as processing conditions. In this work, studies onthe influence of experimental parameters using the dip coating method were performed. Factors suchas residence time (Rt), a curing step between each dip step and the number of layers of sol–gel OIHfilms deposited on HDGS to prevent corrosion in highly alkaline environments were studied. These OIHcoatings were obtained using a functionalized siloxane, 3-isociantepropyltriethoxysilane that reactedwith a diamino-functionalized oligopolymer (Jeffamine®D-230). The barrier efficiency of OIH coatings insimulated concrete pore solutions (SCPS) was assessed in the first moments of contact, by electrochemicalimpedance spectroscopy and potentiodynamic methods. The durability and stability of the OIH coatings inSCPS was monitored during eight days by macrocell current density. The morphological characterizationof the surface was performed by scanning electronic microscopy before and after exposure to SCPS.Glow discharge optical emission spectroscopy was used to obtain quantitative composition profiles toinvestigate the thickness of the OIH coatings as a function of the number of layers deposited and theinfluence of the Rt in the coating thickness.
Resumo:
Organic-inorganic hybrid (OIH) sol-gel coatings based on ureasilicates (U(X)) have promising properties for use as eco-friendly coatings on hot dip galvanized steel (HDGS) and may be considered potential substitutes for pre-treatment systems containing Cr(VI). These OIH coatings reduce corrosion activity during the initial stages of contact of the HDGS samples with highly alkaline environments (cementitious media) and allow the mitigation of harmful effects of an initial excessive reaction between cement pastes and the zinc layer. However, the behavior of HDGS coated with U(X) in the presence of chloride ions has never been reported. In this paper, the performance of HDGS coated with five different U(X) coatings was assessed by electrochemical measurements in chloride-contaminated simulated concrete pore solution (SCPS). U(X) sol-gel coatings were produced and deposited on HDGS by a dip coating method. The coatings performance was evaluated by electrochemical impedance spectroscopy, potentiodynamic polarization curves measurements, macrocell current density and polarization resistance in contact with chloride-contaminated SCPS. The SEM/EDS analyses of the coatings before and after the tests were also performed. The results showed that the HDGS samples coated with the OIH coatings exhibited enhanced corrosion resistance to chloride ions when compared to uncoated galvanized steel.
Resumo:
OBJECTIVE: To use published Hypertension Optimal Treatment (HOT) Study data to evaluate changes in cardiovascular mortality in nondiabetic hypertensive patients according to the degree of reduction in their diastolic blood pressure. METHODS: In the HOT Study, 18,700 patients from various centers were allocated at random to groups having different objectives of for diastolic blood pressure: <=90 (n=6264); <=85 (n=6264); <=80mmHg (n=6262). Felodipine was the basic drug used. Other antihypertensive drugs were administered in a sequential manner, aiming at the objectives of diastolic blood pressure reduction. RESULTS: The group of nondiabetic hypertensive subjects with diastolic pressure<=80mmHg had a cardiovascular mortality ratio of 4.1/1000 patients/year, 35.5% higher than the group with diastolic pressure <=90mmHg (cardiovascular mortality ratio, 3.1/1000 patients/year). In contrast, diabetic patients allocated to the diastolic pressure objective group of <=80mmHg had a 66.7% reduction in cardiovascular mortality (3.7/1000 patients/year) when compared with the diastolic pressure group of <=90mmHg (cardiovascular mortality ratio, 11.1/1000 patients/year). CONCLUSION: The results indicate that in hypertensive diabetic patients reduction in diastolic blood pressure to levels <=80mmHg decreases the risk of fatal cardiovascular events. It remains necessary to define the level of diastolic blood pressure <=90mmHg at which maximal reduction in cardiovascular mortality is obtained for nondiabetics.
Resumo:
The sample under investigation in this project is an experimental chromium enriched yeast used as a possible additive in animal foodstuff, which was produced by growing yeast in the presence of chromium (III) chloride. Chromium on its own in not biologically active but chromium in the form of chromium enriched yeast is biologically active. The objective of this project was to show the complete absence of chromium(VI) from the sample. A literature survey describing previous work carried out on the speciation of Cr(VI) has been carried out. The principal methods of detection of Cr(VI) used in this project are Polarography, G.F.A.A. Spectroscopy, U.V. Spectroscopy and H.P.L.C. For each of the above methods a calibration curve was obtained and each method was applied to the yeast extract. The H.P.L.C. and U.V. spectroscopic method are specific for Cr(VI) but polarography and G.F.A.A. spectroscopy measure total chromium. Tris-NaOH buffer has been investigated for the extraction of chromium(VT). Problems associated with air oxidation of Cr(III) in alkaline solution have identified and procedures described for the suppression of air oxidation. Procedures are described for the application of the extraction procedure to the yeast extract and for the determination of Cr(VI) in the extract. Procedures are also described for the preconcentration of Cr(VI) on a HPLC column and for the application to the yeast extract. The rate of reduction of Cr(VI) by ascorbic acid is investigated and found to be first order with respect to ascorbic acid concentration. The reduction capacity of the yeast is also investigated and it was found that in acid solution the yeast will reduce Cr(VI) but in neutral or basic solution the reduction capacity is diminished. Conclusions regarding the objectives of the project are drawn and suggestions for further work are given.
Resumo:
Young coffee plants (Coffea arabica L., var. Mundo Novo) were grown in nutrient solution purified from micronutrients contaminants by the method of MUNNS & JOHNSON (1960). All plants, except those in the control treatment, wer given all macronutrients and all micronutrients except one which was omitted in order to induce its shortage. Symptoms of deficiency were obtained for all known micronutrients but chlorine. Measurements, observations and chemical analysis of leaves allowed the following main conclusions to be drawn. 1. The relative influence of micronutrients in growth-measured by the fresh weight of the entire plant - was as follows: -Fe -Zn -Cu -Mo -Mn complete = -B = -CI. that is: the omission of iron from the nutrient solution caused the severest reduction in growth; lack of B and Cl had no effect. 2. Symptoms of deficiency of B, Fe, Mn, and Zn were found to be in good agreement with those in the literature. Effects of Cu and Mo shortage, however, had not been described so far: In the case of the Cu-deficient plants, the younger leaves were distorted, having an "S" shape, due probably to lack of growth of the veins; they lost their green color and developed rather large, necrotic patches near the margins. When molybdenum was omitted from the nutrient solution yellow spots develop near the margen of subterminal (fully mature) leaves; they became necrotic; there was a characteristic downward curling of the leaf blade along the mid rib so that the opposite edges touched each other underneath. 3. The levels of micronutrients found in normal and deficient leaves are given in Table 4. It is hoped that those values will serve as a basis of judgement of micronutrient contents found in leaves of field grown plants.
Resumo:
Plantas de cebola Allium cepa L. var. Baia Piriforme precoce de Piracicaba, foram cultivadas em vasos contendo silica. Foram irrigadas diversas vêzes ao dia com solução nutritiva completa e deficiente nos macronutrientes. Às plantas exibiram sintomas de carência na seguinte ordem de aparecimento: nitrogênio, cálcio, fósforo, potássio, magnésio e enxôfre. Os nutrientes foram extraídos em mg pela cebola na seguinte ordem: potássio-992, nitrogênio-658, enxôfre-168, cálcio-103, fósforo-84, magnésio-73.
Resumo:
Magdeburg, Univ., Fak. für Mathematik, Diss., 2014