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Copyright of RSBO: Revista Sul-Brasileira de Odontologia is the property of UNIVILLE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work presents an evaluation of a new paste applied to the abrasive flow machining (AFM) process, a paste developed with oiticica oil, from the "Licânia rígida Benth," originating from Brazil. The application of the paste with vegetable oil will be compared with results obtained by a commercial paste during the application of AFM in medium carbon steel SAE 1045 and aluminum 6061-T6 workpieces in terms of surface roughness (Ra, Rq, and Rz parameters) and number of cycles. A statistical analysis of the data was applied to the surface roughness results through a factorial design, considering a level of significance of 5% and a hypothesis test above 0.90, to validate the experimental tests. Reductions in the surface roughness values were obtained with the paste developed in the machining of steel workpieces, indicating that factors such as work material, number of cycles, and type of abrasive grain can influence the final result of the AFM machining. [ABSTRACT FROM AUTHOR]

In order to research roughness of rock fracture surfaces and interior damaged status of rock, some Brazil discs of white marble and sandstone are loaded to fracture by Brazil Test and the mathematical model of fractal variation is used to distinguish the morphology characterization of fracture surface of white marble from that of sandstone. Through computing the acquired scanned data of rock fracture surfaces, the following three results are obtained. First, the roughness of fracture surface increases with increase of loading angles, furthermore, the anisotropy of white marble fracture surface is more obvious than that of sandstone one. Second, under the same loading mode, by analyzing the mean fractal variation, the fracture surface of white marble is rougher than that of sandstone. Finally, rock disc specimens loaded to 1/2 or 3/4 of mechanics of mean fracture threshold still do not fracture at the first time loading, but their interiors have been badly damaged. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the development of a simulation model, which was incorporated into a Geographic Information System (GIS) in order to calculate the maximum intensity of urban heat islands (UHI max ) based on urban geometry data (using a H/W parameter). This tool is called THIS – Tool for Heat Island Simulation. The urban heat island phenomenon is defined by the temperature rise in dense city centers compared with the surrounding countryside. The methodology of this study is based on a theoretical-numerical basis (Oke model), followed by the development of a calculation algorithm incorporated into the GIS platform, which is then adjusted and applied as exemplification. This adjustment was made by calibrating the Oke model for a case study based on two Brazilian cities and different various trends for different roughness length ranges were found. As a consequence, this work has resulted in the automation of an algorithm to obtain maximum intensity values of heat islands based on a simplified model. After finishing the subroutine, the application of the THIS in a simulation of different urban scenarios showed different trends in the UHI max value for the H/W ratio and the roughness length. The UHI max increases when the H/W ratio increases, but the urban canyons with greater roughness (larger areas of facades and more heterogeneous heights, Z 0 ≥ 2.0) result in UHI max values of approximately two times smaller than canyons with less roughness (homogeneous with highest average areas occupied by buildings, Z 0 < 2.0) for the same value as the H/W ratio. Overall, the developed tool has one aim: to simulate the effect of the isolated variable of urban geometry on the maximum intensity of nocturnal heat islands, considering different urban scenarios. [ABSTRACT FROM AUTHOR]

In recent decades, the micro-region of Paraiba state, Brazil, has been undergoing the process of replacing its native coverage by crops, mainly pastures for grazing. This land use change has led to the detachment of soil due to the water erosion. Thus, this research had the merit of analyzing the hydraulic roughness parameters generated by pasture emergent vegetation in field condition under interrill erosion. This study was conducted in a randomized block with 4 treatments and 5 replicates, totaling 20 experimental plots. The treatments comprised different slopes (15%, 25%, 35% and 45%) in an Ultisol. The mean flow velocity and the rate of infiltration in the pasture varied significantly with the increase in slope, contributing to increasing erosion rates until 35% slope. For the slope equal to 45%, the largest soil loss was not observed, chiefly because the crop covers offset the effects generated by the increase in the slope and also due to the remotion of surface horizon (A horizon) which was removed by previous water erosion, which now acted directly on the B horizon. The vegetation drag coefficient ( C D ′) of the pasture exhibited an increase when occurred a reduction of turbulent flow between plants. In the condition of increasing in flow depth (h) there was a greater energy flux between the mass of water and the plant structure of Brachiaria decumbens that resulted in the decrease of the vegetation resistance force (Fdrag). [ABSTRACT FROM AUTHOR]

Corn is widely consumed in Brazil and spray drying allows for versatility in its use. This study aimed to evaluate the effects of maltodextrin concentrations and the inlet air temperature on the physical properties of green corn extract dried by spray drying. A central composite rotatable design (CCRD) was applied with the independent variables of inlet air temperature of 150–180°C and maltodextrin concentration of 0–20% (w/w). An inlet air temperature of 163°C and a maltodextrin concentration of 2.67% (w/w) displayed a good drying performance in relation to the yield (36.36%), moisture (1.39%), activity water (0.063), solubility (92.11g/100g), wettability (139.58g/s), density (0.66g/mL) and colour (L: 92.50, C*: 15.47 and h°: 97.46) closest to the green corn extract. The microstructure indicated surface roughness and particle size D50 ranged from 5.79 to 75.84μm. [ABSTRACT FROM AUTHOR]

Cross-linked polyethylene (XLPE) has been the most common insulation applied to medium voltage covered conductors (MVCCs) in Brazil. The results of accelerated aging tests carried out at high voltage laboratory of UNIFEI (LAT-EFEI), combining the stresses of heat and voltage to ground aiming at enhancing surface corona activity assays, have identified the early failures in XLPE insulations of the Brazilian MVCCs. The observed failures indicate that complementary studies should be performed to better understand the degradation mechanisms of the MVCCs insulations manufactured in Brazil. In this paper, x-ray photoelectron spectroscopy (XPS), contact angle analysis (CA), photoacoustic spectroscopy (PAS), x-ray diffraction (XRD), and atomic force microscopy (AFM) measurements on samples of five Brazilian national/regional MVCCs are reported. XPS, CA, and PAS analysis indicated that a large variety of oxygen-containing groups associated to the oxidation of the XLPE insulations appear to be related to the manufacturing conditions. AFM analysis indicated that the average surface roughness and topography of the XLPE insulation changed significantly and depend on the selected manufacturer. XRD analysis indicates a strong heterogeneity of crystals nucleation that results into different degrees of crystallinity of the Brazilian MVCCs cables. The results of this work indicate strong evidences of manufacturing defects in the XLPE insulation of Brazilian's MVCCs. The origin of these defects seems to be inherent to the technology used by manufacturers to the production of the MVCCs. The production-related defects are not detectable by the standard tests as partial discharges or even the standard routine-acceptance power frequency assays routinely used in dielectric compatibility tests at high voltage laboratories. [ABSTRACT FROM AUTHOR]

The dwarf-green coir fibers treated with sodium hydroxide 10% produced the best set of properties of the biocomposites generated: greater roughness and exposure of intrafibrillar cavities, providing better adhesion with the matrix, higher rigidity, increased resistance to traction and better interface properties, making them better as structural materials. The best results reported in the thermal behavior of biocomposite fibers were found in fibers treated with sodium hydroxide 10%. These showed a single stage of decomposition, which occurs at a higher temperature (300°C). It was observed that the natural fibers were more resistant to the action of the microorganisms due to the presence of more lignin and hemicellulose, while fibers treated with 5 and 10% sodium hydroxide showed different degradation degree. [ABSTRACT FROM AUTHOR]

This study experimentally investigates the influence of intruder surface roughness in the Brazil nut effect in a quasi-two-dimensional vertical vibration granular bed. The intruder dynamics are determined using a particle-tracking method. The results show that surface roughness has a crucial role in the intruder rise dynamics; a rougher intruder has more difficulty rising in the bed because of higher kinetic energy dissipation. This study determined that penetration length and drag length are reduced and drag is enhanced as intruder surface roughness increases. The exponential decay of the penetration length with vibration frequency is shown. The results also show that at higher dimensionless vibration acceleration and lower vibration frequency the variation in rise time between smooth and rough intruders is negligible. [ABSTRACT FROM AUTHOR]

Introduction: The quality of the bone-implant interface is directly influenced by implant surface roughness and a roughness average, with the Sa between 1 to 2µm, has demonstrated better clinical and laboratory results. In Brazil, more than two million implants per year are installed, where 79% are manufactured by domestic companies. However, very little is known or published about the characterization of surfaces of these implants, on the micrometer level. The aims of this study are to evaluate and characterize numerically the surface of the implants of SIN (Sistema de Implante Nacional) company, one of the five largest companies in the Brazilian market. Methods: Were evaluated a total of 6 implants, purchased directly on the market, of two different designs (Tryon-HE and Strong-SW) and different batches, using light interferometry. Were performed 9 measurements randomly chosen for each unit, 3 on the tops, 3 on the valleys and 3 on the flanks of the threads. The same pattern was followed for evaluation by scanning electron microscope. Results: the analyzed implants from this company showed Sa values of 0.84μm for Tryon-HE and 1.01μm for Strong SW. Comparing the batches, only the SW design showed statistically significant differences between them. Conclusions: the roughness values found herein categorize the surfaces of Tryon-HE as minimally rough, and Strong-SW implants as moderately rough. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of RGO: Revista Gaúcha de Odontologia is the property of RGO: Revista Gaucha de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Knowledge on evapotranspiration is essential in quantifying water use depletion and to allocate scarce water resources to competing uses. Despite that an extensive literature describes the theoretical mechanisms of turbulent water vapour transport above and within crop canopies fewer studies have examined land surface parameters within composite landscapes of irrigated crops and semi-arid natural vegetation. Aiming to improve parameterizations of the radiation and energy balance in irrigated crops and natural vegetation, micro-climatic measurements were carried out on irrigated land (vineyards and mango orchard) and natural vegetation (caatinga) in the semi-arid zone of the São Francisco River basin (Brazil) from 2002 to 2005. The fractions of 24h incident solar radiation available for net radiation were 46%, 55%, 51% and 53%, for wine grape, table grape, mango orchard and caatinga, respectively. Daily evaporative fractions of the net available energy used as latent heat flux (λE) were 0.80, 0.88, 0.75 and 0.33 respectively. The daylight values of bulk surface resistances (r s) averaged 128sm−1, 73sm−1, 133sm−1 and 1940sm−1 for wine grape, table grape, mango orchard and caatinga, respectively. Simplified parameterizations on roughness and evaporation resistances were performed. It could be concluded that net radiation can be estimated by means of a linear expression with incident global solar radiation depending on the type of vegetation. The variability of aerodynamic resistance (r a) could be mainly explained by the friction velocity (u∗ ) which on turn depends on the surface roughness length for momentum transport (z0m ). The experimental data showed that for sparse canopies z0m being 9% of the mean vegetation height is a doable operational rule for the semi-arid region of São Francisco River basin. The seasonal values of r s for irrigated crops were highly correlated with water vapour pressure deficit. The availability of analytical methods to assess r a and r s makes the one-step Penman–Monteith equation suitable for the computation of actual evapotranspiration and water productivity analyses. [Copyright &y& Elsevier]

• Paint exposed for 2y in São Paulo, Pirassununga, São Sebastião and Belém, Brazil. • The lowest value of the reflectance was 0.49. • Highest surface roughness increase, caused by thicker biofilms, was 1.80. • Natural aging studies needed in Brazil for improving durability of "cool" surfaces. Solar reflectance and thermal emittance are fundamental parameters in the evaluation of a building's thermal and energetic performance, particularly important for "cool" surfaces. However, there is little information on typical values of these parameters in Brazil. We determined values of reflectance, thermal emittance, surface roughness and color difference, for a white high-reflectance paint exposed for two years in 4 cities in the States of São Paulo (SP) and Pará (PA), south-eastern and north Brazil, respectively. After 2 years, painted panels exposed in Pirassununga, SP, showed significantly lower reflectance and increased color difference compared with the original paint and the panels exposed at other sites. This appeared to be related to the presence of a biofilm, in addition to particles of the red clay characteristic of this area. This was likely also to be the explanation of the increased surface roughness determined in Pirassununga samples. Emissivity of the paint changed very little at any of the exposure sites over 2 years, but Solar Reflectance Index, calculated from the average values of reflectance and emittance in the four cities, was reduced from between 105 and 107 to between 94 (in São Sebastião, SP) and 77 (in Pirassununga, SP) after two years. Macroscopically, panels from Pirassununga and Belém, were the most discolored and the greatest presence of biofilm was demonstrated by digital and scanning electron microscopy. Such natural aging studies are important for the production of standard tests and determination of control strategies to increase durability of cool surfaces in Brazil. [ABSTRACT FROM AUTHOR]

Conducting research in the field of forensic sciences with methodologies that simulate situations found in the day-to-day practice of a given field of expertise is relevant insofar as this approach can produce results that are as close as possible to reality. In this context, the present study provided situations based on burial in a mangrove environment to estimate the changes in the mechanical properties (Knoop microhardness, roughness and color) of dental restorations utilizing silver amalgam, composite resin and glass ionomer cement over the time of burial. The silver amalgam showed a significant increase in surface roughness and a reduction in Knoop microhardness. Composite resin showed a statistically significant increase in color variation, and the glass ionomer cement showed significant increases in color variation and Knoop microhardness. These results allowed us to conclude that teeth restored with silver amalgam, composite resin and glass ionomer cement submitted to burial in mangrove environments produce different changes in surface roughness, Knoop microhardness and color properties depending on the time of burial to which the victims were submitted. These proprieties could help the forensic sciences to estimate time intervals for burial in mangrove environments. [ABSTRACT FROM AUTHOR]