867 resultados para validação de limpeza


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Indiscriminate and inappropriate use of pesticides in agriculture has been pointed out for increasing health problems and environmental damage. Considering that water resources are the principal destiny of those compounds after application, the present study presents optimization and validation of two simple and effi cient analytical methods for pesticides quantifi cation in both surface and groundwater. Were selected the pesticides more commonly used at Dourados (MS - Brazil), region with intense agricultural activity. Pesticides were preconcentrated by solid-phase extraction using C18 (500 mg) cartridges and then divided in two groups for elution and quantifi cation: 2.4-D and 2.4-DCP were eluted with methanol and quantifi ed by high performance liquid chromatography with ultra-violet detector (HPLC-UV) while atrazine, DIA, DEA, trifl uralin and methyl parathion were eluted with ethylacetate (1:1, v/v) and quantifi ed by gas chromatography with thermionic specifi c detector (GC-TSD). The methods showed satisfactory accuracy (76-107%) and precision (<12%) for the substances analyzed at the fortifi ed levels selected for the study, except for DIA (<51%). Study of pesticide stability also presented good results: C18 cartridges could be stored for at least for 21 days at -20ºC with no signs of the compounds degradability. Both methods limits of quantifi cation of the pesticides (0.22 - 0.48 μg L-1) are in accordance to the levels currently established by the Brazilian national legislation for pesticides in water. Although only the pesticide 2.4-D has been detected in two distinct collection points in the study period of time, this work warns for the requirement of systematical analysis of pesticides presence in water destined to human consume, principally in areas of intense agriculture activity. Such monitoring can provide subsidies for public environmental policies.

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Pós-graduação em Microbiologia Agropecuária - FCAV

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The objective of this study was to develop a model that allows testing in the wind tunnel at high angles of attack and validates its most critical components by analyzing the results of simulations in finite element software. During the project this structure suffered major loads identified during the flight conditions and, from these, we calculated the stresses in critical regions defined as the parts of the model that have higher failure probabilities. All aspects associated with Load methods, mesh refining and stress analysis were taken into account in this approach. The selection of the analysis software was based on project needs, seeking greater ease of modeling and simulation. We opted for the software ANSYS® since the entire project is being developed in CAD platforms enabling a friendly integration between software's modeling and analysis

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This article aims to describe the proposed development of an emulator application for digital TV that operates on a local computer network, to have it as a testing environment for students and researchers. The emulator application is presented as a useful tool to reduce validation costs of applications developed for digital TV.

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Introduction: Currently, there are many questions regarding the cleaning methods seeking greater efficiency and less loss of burs. Aim: the aim of this study was to evaluate the influence of cleaning methods on the cutting efficiency and morphological characteristics of stainless steel burs tungsten carbide (carbide). Materials and method: Thirty burs were divided into five groups (n = 5) according with the cleaning method: L1 - steel brush, L2 - nylon brush, L3 - ultrasound  +  distilled water, L4 - ultrasound + descaling solution and L5 - no cleaning method (control). The burs were used for the cutting of bovine enamel during six periods of 12 minutes each. After each period, the burs were cleaned (except L5 ) following the protocol established for each group. The cutting efficiency was determined by mass loss and morphological characteristics. Result: The average amount of wear after 72 minutes of use were L1  = 0.3558 g; L2  = 0.4275 g; L3  = 0.4652 g; L4  = 0.4396 g e L5  = 0.4854 g; significant differences in the time of use (p  <  0.001) and cleaning method (p  <  0.001). The L1 group showed the worst performance. Regardless of the experimental group, morphological analysis revealed alterations in the cutting blades soon after the first 12 minutes, being L1 the most affected group. Conclusion: The cleaning with wire brush was the most damaging method to the cutting efficiency and to the morphology of carbide burs.

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The irrigation of root canals aims to their cleaning and disinfection, improving endodontic treatment success. OBJECTIVE: To investigate the influence of the diameter and type of irrigation needle and the root canal enlargement on the mechanical efficacy of endodontic irrigation. MATERIAL AND METHODS: Twelve human single-rooted mandibular incisors were used. During some instrumentation stages (enlargement by #20, #30, and #40 K file), root canals were filled with radiographic contrast solution mixed to propyleneglycol and zinc oxide. Needles with different diameters and designs were employed: G1 – 23G and lateral opening; G2 – 22G and apical opening; G3 – 30G and lateral opening; G4 – 30G and apical opening. The needles were inserted up to resistance, with 1 mm step-back to avoid root canal obliteration. The irrigation was performed with 2 mL of distilled water. Before and after irrigation/aspiration, teeth were radiographed at bucco-lingual and mesiodistal direction, using a digital radiographic system. Then, root canal areas, before (filled by contrast solution) and after irrigation (remnant of contrast solution), were submitted to image subtraction with Adobe Photoshop CS4 software. Subsequently, the areas were measured by Image Tool 3.0 software, allowing the obtaining of the cleaning percentage for each modality. Data were analysed by using Anova and Tukey's test. The level of significance was set at P < 0.05. RESULTS: For all root canal enlargements, 30G needles (G3 e G4) presented a better cleaning efficacy. In all groups, higher cleaning efficacy percentage was observed at #30 and #40 K file enlargement. CONCLUSION: Regardless their design, thinner needles were more effective; a better cleaning efficacy occurred in more enlarged root canals.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Fonoaudiologia - FFC

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Post-Occupancy Evaluation of buildings considers user satisfaction, building pathologies and performance, as well as users interventions in the built environment. The possibility of identifying interventions regardless of the user could provide a significant gain in the efficiency of Post-Occupancy Evaluations. We foresee the application of Augmented Reality (AR) to improve the identification of renovations by overlapping the construction information model with an image of the actual building. This article validates the use of AR on existing smartphone and tablet applications. This study proposes the incorporation of AR into the planning, execution and application of Post-Occupancy Evaluation. For the planning, this study proposes the development of a new research tool. With regards to the execution, this study examined the data collection conditions on site through the visualization of overlapping models. For the application, this study proposes displaying the results through the use of RA information layers. The transparency oft he RA model was used to allow comparison between the virtual model and the real model. The development and adaptation of the virtual model and the solution developed for the experiment of the RA proposal are presented and discussed. The experiment points to shortcomings that still make the proposed technological solution unfeasible.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)