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41.
Y. L. Machado A. A. Dantas Neto J. L. C. Fonseca T. N. C. Dantas 《Journal of the American Oil Chemists' Society》2014,91(7):1139-1145
The PetroOXY method was used to evaluate the kinetics of oxidation of two edible vegetable oils, extracted from moringa and passion fruit. This method, which uses pure oxygen at 700 kPa is effective and fast and our experiments were carried out at temperatures 110–140 °C with BHA antioxidant additive concentration ranging from 0 to 500 ppm. Moringa and passion fruit oils followed first-order kinetics although, in the case of passion fruit oil, mathematical approximations in the first-order kinetic expression resulted in a final equation that could also be interpreted as deriving from zero-order kinetics. The higher stability of moringa oil was characterized by an activation enthalpy ca. 50 % higher than the one related to passion fruit oil. 相似文献
42.
André Medeiros De Andrade Roberto Ferreira Machado Michel Ulisses Franz Bremer Carlos Ernesto Gonçalves Reynaud Schaefer Jefferson Cardia Simões 《International journal of remote sensing》2018,39(8):2238-2254
The aim of this work is to produce a simplified vegetation map of ice-free areas of the Fildes Peninsula (FP) and Ardley Island (AI) thought object-oriented classification using a QuickBird satellite image and to evaluate the influence of the global solar radiation (GSR) over the vegetation distribution. The vegetation data were generated from multiresolution segmentation using the panchromatic and infrared layers, and for the classification we calculated the normalized vegetative difference index (NVDI) and the green NVDI. Two classes were created – Lichen and Moss Cushion SubFormation and Moss Subformation – with 48 vegetation samples collected on surveys during the austral summers of 2008 and 2009. We used a kappa index to evaluate the classification efficiency using 100 sampled points obtained in austral summer of 2013. The GSR was estimated, and in order to evaluate the effect of meteorological phenomena and cloudless, we measured the GSR using a net radiometer model CNR4 installed in FP between 2014 and 2016. The estimate of GSR was done for seasons of 2015, in order to estimate the light compensation point and the saturation point for the plant communities in FP and AI. The kappa index was 0.73 and the global accuracy was 0.78, showing consistency between the classification and ground truth. The area was covered by vegetation in FP was 16.7% and in AI is 59.1%. The vegetation cover is distributed differently at FP and AI, and our results suggest GSR plays an important role in vegetation distribution and these tendencies could be related to greater GSR demand by mosses when compared to lichens. 相似文献
43.
Characterization of a water-based paint for corrosion protection 总被引:1,自引:0,他引:1
Paula Dias Catarina Carneiro Luísa Andrade José Sousa João Machado Adélio Mendes 《Journal of Coatings Technology and Research》2012,9(3):365-374
Corrosion of steel rebars in reinforced concrete is one of the major problems in the construction industry. Carbonation reactions
of concrete with carbon dioxide and, mainly, the chloride salts action are the main causes responsible for concrete degradation.
Protective coatings help to improve the durability of concrete structures by acting as a physical barrier against the corrosion
agents. Waterborne paints are usually used for concrete protection rather than solvent-based paints since they are less pollutant.
The aim of this work is to investigate the influence of the pore size and porosity on the permeability of the paints films
toward sodium chloride. Three characterization methods from membrane science were implemented to characterize paint coatings.
The time-lag method was used to determine the permeability toward the sodium chloride and toward helium and argon, these for
approximately 100% relative humidity. From the seven waterborne paints formulated, only one was found to be suitable for surface
protection of reinforced concrete, since its permeability toward NaCl was smaller than 10−14 m2 s−1, the threshold value required by National Laboratory of Civil Engineering (LNEC) in Portugal. For the formulated paints,
it was observed that the average pore size correlates well with the permeability toward sodium chloride. This is an important
result since obtaining the permeability toward sodium chloride of corrosion protective paints is very time consuming, while
the average pore size can be obtained in a much shorter time. 相似文献
44.
Guilherme Galante Luis Carlos Erpen De Bona Antonio Roberto Mury Bruno Schulze Rodrigo da Rosa Righi 《Journal of Grid Computing》2016,14(2):193-216
Elasticity can be seen as the ability of a system to increase or decrease the computing resources allocated in a dynamic and on demand way. It is an important feature provided by cloud computing, that has been widely used in web applications and is also gaining attention in the scientific community. Considering the possibilities of using elasticity in this context, a question arises: “Are the available public cloud solutions suitable to provide elasticity to scientific applications?” To answer the question, in a first moment we present a survey on the use of cloud computing in scientific scenarios, providing an overview of the subject. Next, we describe the elasticity mechanisms offered by major public cloud providers and analyzes the limitations of the solutions in providing elasticity for scientific applications. As the main contribution of the article, we also present an analysis over some initiatives that are being developed to overcome the current challenges. In our opinion, current computational clouds are developing rapidly but have not yet reached the necessary maturity level to meet all scientific applications elasticity requirements. We expect that in the coming years the efforts being taken by numerous researchers in this area identify and address these challenges and lead to better and more mature technologies that will improve cloud computing practices. 相似文献
45.
Biosynthesis and purification of histidine‐tagged human soluble catechol‐O‐methyltransferase
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46.
Tactic planning or master production scheduling focuses on time and spatial decomposition of the aggregate planning targets and forecasts, as well as, forecast and provision of needed resources. This process becomes extremely hard and time consuming with the increase of number of products, resources and periods considered. In face of such obstacles, this work shows a study of an Artificial Intelligence technique called Simulated Annealing applied to the optimization of production planning problem, more specifically, Master Production Scheduling. This work reviews some of the fundamental theory of simulated annealing, the methodology for master production scheduling calculation, the applicability of simulating annealing to planning problems, most important results and suggestions for further studies. 相似文献
47.
Dairy cow lameness is a serious animal welfare issue. It is also a significant cause of economic losses, reducing reproductive efficiency and milk production and increasing culling rates. The digital cushion is a complex structure composed mostly of adipose tissue located underneath the distal phalanx and has recently been phenotypically associated with incidence of claw horn disruption lesions (CHDL); namely, sole ulcers and white line disease. The objective of this study was to characterize digital cushion thickness genetically and to investigate its association with body condition score (BCS), locomotion score (LOCO), CHDL, and milk production. Data were collected from 1 large closely monitored commercial dairy farm located in upstate New York; 923 dairy cows were used. Before trimming, the following data were collected by a member of the research team: BCS, cow height measurement, and LOCO. Presence or not of CHDL (sole ulcer or white line disease, or both) was recorded at trimming. Immediately after the cows were hoof trimmed, they underwent digital sonographic B-mode examination for the measurement of digital cushion thickness. Factors such as parity number, stage of lactation, calving date, mature-equivalent 305-d milk yield (ME305MY), and pedigree information were obtained from the farm’s dairy management software (DairyCOMP 305; Valley Agricultural Software, Tulare, CA). Univariate animal models were used to obtain variance component estimations for each studied trait (CHDL, BCS, digital cushion thickness average, LOCO, height, and ME305MY) and a 6-variate analysis was conducted to estimate the genetic, residual, and phenotypic correlations between the studied traits. The heritability estimate of DCTA was 0.33 ± 0.09, whereas a statistically significant genetic correlation was estimated between DCTA and CHDL (−0.60 ± 0.29). Of the other genetic correlations, significant estimates were derived for BCS with LOCO (−0.49 ± 0.19) and ME305MY (−0.48 ± 0.20). Digital cushion thickness is moderately heritable and genetically strongly correlated with CHDL. 相似文献
48.
Elton Joao Zierhut Rodrigo Battisti Ricardo Antonio Francisco Machado Cintia Marangoni 《化学工程与技术》2020,43(9):1884-1896
Intrinsic characteristics of distillation such as dead time and high nonlinearities do not allow the complete elimination of transient times when any external disturbance or set-point change occurs. Thus, aiming at the use of easy-tuning systems, a distributed-action control in trays of a diabatic distillation unit with Smith's predictor was implemented in the Simulink environment to further reduce transient times and out-of-specification product. The distributed-action strategy with Smith's predictor led to a reduction of 33.3 min (33 %) in the transient time of the top temperature control loop and 66 % in out-of-specification product, when compared with the conventional strategy, and thus is shown to be an efficient approach to increasing the productivity of distillation plants. 相似文献
49.
Liu Shuai Bai Weiling Srivastava Gautam Machado J. A. Tenreiro 《Mobile Networks and Applications》2020,25(4):1537-1547
Mobile Networks and Applications - The increment of communication technologies and the development of signal processing require efficient identification techniques for communication... 相似文献
50.
Vanessa Migliorini Urban Ana Lucia Machado Carlos Eduardo Vergani Eunice Teresinha Giampaolo Ana Cláudia Pavarina Quezia Bezerra Cass 《应用聚合物科学杂志》2012,123(2):732-739
The effect of a post‐polymerization treatment on the leaching of methacrylic acid (MA) and benzoic acid (BA) from the reline resins [Kooliner (K), New Truliner (N), Ufi Gel hard (U), and Tokuso Rebase Fast (T)] was evaluated. Specimens of each material were divided into two groups: Group C (control) – left untreated; Group WB (water‐bath) – immersion in water at 55 ± 1°C for 10 min. Specimens were placed in artificial saliva at 37 ± 1°C and, after 1‐, 3‐, 5‐, 24‐h and 3‐, 7‐, 14‐, and 30‐day intervals, aliquots were removed and analyzed using high performance liquid chromatography. Data were analyzed by using Wilcoxon, Mann–Whitney or Kruskal–Wallis tests (α = 0.05). At 1 h, the concentration of MA released from U control specimens was higher than those of the other ones, and decreased after 3 h. WB specimens released lower amounts of MA than control specimens only for material U, at the 1‐ and 3‐h periods. For all control specimens, concentrations of leached BA progressively decreased within 5 h and from 24 h to the end. WB specimens released significantly lower amounts of BA than did the control groups. The highest concentration of MA was leached from control specimens of Ufi Gel hard. Water‐bath post‐polymerization treatment caused a significant reduction in elution of BA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献