67 resultados para Horizontal Infiltration


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The antibiotics sulfamethoxazole (SMTX) and ciprofloxacin (CIP) are commonly used in human and veterinary medicine, which explains their occurrence in wastewater. Anaerobic reactors are low-cost, simple and suitable technology to wastewater treatment, but there is a lack of studies related to the removal efficiency of antibiotics. To overcome this knowledge gap, the objective of this study was to evaluate the removal kinetics of SMTX and CIP using a horizontal-flow anaerobic immobilized biomass reactor. Two different concentrations were evaluated, for SMTX 20 and 40 μg L(-1); for CIP 2.0 and 5.0 μg L(-1). The affluent and effluent analysis was carried out in liquid chromatography/tandem mass spectrometry (LC-MS/MS) with the sample preparation procedure using an off-line solid-phase extraction. This method was developed, validated and successfully applied for monitoring the affluent and effluent samples. The removal efficiency found for both antibiotics at the two concentrations studied was 97%. Chemical oxygen demand (COD) exhibited kinetic constants that were different from that observed for the antibiotics, indicating the absence of co-metabolism. Also, though the antibiotic concentration was increased, there was no inhibitory effect in the removal of COD and antibiotics.

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Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA

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Purpose: In order to assist in the selection of artificial teeth for complete dentures, this study aimed to assess the relationship between horizontal and vertical measurements of the face and the morphology of the maxillary central incisor. Materials and Methods: This was a study of 50 plaster casts and 100 teleradiographs - 50 in lateral norm and 50 in frontal norm, belonging to 50 individuals, Caucasian, with a naturally optimal occlusion, matching at least four of the six keys of Andrews. Images of the upper central incisors were obtained by scanning the plaster casts (three-dimensional) and subjectively classified by three examiners as oval, triangular or quadrangular. Facial measures (vertical and horizontal) were defined by means of teleradiographs. In order to check inter-examiner agreement on the classification of central incisor, the Kappa test was used. To verify whether data had normal distribution, the Kolmogorov-Smirnov test was used ( P > 0.2) was used. One-way analysis of variance was employed to assess the association between variables (P > 0.05). Results: When vertical measurements were compared with the three incisor shapes, there was no statistically significant difference (P > 0.05): Triangular (0.54), oval (0.63) and quadrangular (0.51). Similarly, no difference (P > 0.05) was found for facial width (139.08, 143.37, 141.65), maxillary width (76.68, 78.99, 76.91) and mandibular width (103.47, 105.50, 103.11). Conclusions: The majority of cases showed that horizontal and vertical measurements of the face cannot be used as a reference for determining the morphology of the maxillary central incisor crown. It is relevant to analyze and compare other morphological structures to improve the oral health-related quality of life for the conventional denture wearer.

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This paper studies attained microstructures and reactive mechanisms involved in vacuum infiltration of copper aluminate preforms with liquid aluminium. At high temperatures, under vacuum, the inherent alumina film enveloping the metal is overcome, and aluminium is expected to reduce copper aluminate, rendering alumina and copper. Under this approach, copper aluminate toils as a controlled infiltration path for aluminium, resulting in reactive wetting and infiltration of the preforms. Ceramic preforms containing a mixture of Al2O3 and CuAl2O4 were infiltrated with aluminium under distinct vacuum levels and temperatures, and the resulting reaction and infiltration behaviour is discussed. Copper aluminates stability ranges depend on vacuum level and oxygen partial pressure, which determine both CuAl2O4 and CuAlO2 ability for liquid aluminium infiltration. At 1100 °C and 0.76 atm vacuum level CuAl2O4 is stable, indicating pO2 above 0.11 atm. Reactive infiltration is achieved via reaction between aluminium and CuAl2O4; however, fast formation of an alumina film blocking liquid aluminium wicking results in incipient infiltration. At 1000 °C and 3.8 × 10−7 atm vacuum level, CuAlO2 decomposes to Cu and Al2O3 indicating a pO2 below 6.0 × 10−7 atm; infiltration of the ceramic is hindered by the non-wetting behaviour of the resulting metal alloy. At 1000 °C and 1.9 × 10−6 atm vacuum level CuAlO2 is stable, indicating pO2 above 6.0 × 10−7 atm. Extensive infiltration is achieved via redox reaction between aluminium and CuAlO2, rendering a microstructure characterised by uniform distribution of alumina particles amid an aluminium matrix. This work evidences that liquid aluminium infiltration upon copper aluminate-rich preforms is a feasible route to produce Al–matrix alumina-reinforced composites. The associated reduction reaction renders alumina, as fine particulate composite reinforcements, and copper, which dissolves in liquid aluminium contributing as a matrix strengthener.

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The aim of the present study were: 1) To verify the relationship of vertical, horizontal and sextuple jumps with agility and velocity of 5, 10 and 25 m; 2) To verify the capacity of these jumps to predict the agility and 5, 10 and 25 m velocity performance in children. Twenty eight boys (9.47 ± 0.64 years) and thirty girls (9.69 ± 0.70 years) were evaluated. The correlation values between agility and velocity on 5, 10 and 25 m velocity were, respectively, r = 0.63, 0.51, 0.44 and 0.64 with vertical jump, r = 0.68, 0.62, 0.28 and 0.62 with sextuple jump, and r = 0.60, 0.50, 0.26 and 0.57 with horizontal jump. The vertical and sextuple jumps were able to predict the agility and 25 m velocity performance (p < 0.05). Furthermore, they demonstrated capacity to predict 5 and 10 m velocity, respectively (p < 0.05). The vertical and sextuple jump tests may be used for assessment and control of training with children practicing activities that require agility and velocity, since both jumps predicted the agility and velocity performance, which did not occur with the horizontal jump.