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This paper evaluated the behavioural performance to coating mortar water with rubberized tyres. #0.60 mm and #1.19 mm grain sizes have been used with the incorporation of 10 and 20% (in volume), replacing the small units. The methodology has elapsed with capillary and drying tests; humidification and drying procedures with mass control, infrared thermography and measurement of humidity. The results indicated that in capillarity and drying the trace A20F (#0.60 mm particle size and incorporation of 20%) had have a low absorption rate and helped in the process of water disposal. In the humidification and drying process, both active as well as passive, the rubber possibly blocks the pores of mass, for the grain traits size #0.60 mm (A10F and primarily A20F) have proven easy to lose water, suggesting that the majority of water absorbed would be concentrated on the surface part of the composite. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNT) were functionalized with ethanol, nitric and sulfuric acid. From the obtained nanocomposites, electrical permittivity, magnetic permeability and reflectivity complex parameters were studied in the frequency range of 8.2 to 12.4 GHz (X-band). The results of reflectivity for nanocomposites, functionalized with CNT, showed an attenuation of - 21 dB and -18 dB, at the frequency of 10.4 GHz and 12.4 GHz, respectively, with approximately 99% of attenuation, demonstrating, then, that they are promising for application as Radar Absorbing Materials (RAM). [ABSTRACT FROM AUTHOR]

Practically all studies of reservoir engineering involve detailed knowledge of fluid flow characteristics. The fluid flow performance in porous media is affected by pressure, flow rate, and volume of single fluid phases. Permeability is a measure of how well a porous media allows the flow of fluids through it. Permeability and porosity form the two significant characteristics of reservoir rocks. This research aimed to present the design of laboratory equipment to test the ability of fluid flow through different sandstone samples. Two sand core samples (coarse sand sample and fine sand sample) were tested. The laboratory findings measurements of porosity, saturation, total permeability, effective permeability, and relative permeability were evaluated. The laboratory tests were performed on partially saturated, unconsolidated core sand for two-phase fluid flow. The experimental work was developed for measuring the flow capacity achieved under the steady-state conditions method. Various grain sizes sands were selected as a porous medium to determine petrophysical properties and fluid flow capacity of the rock sample. Nitrogen and air were utilized as gas-phases, and, for liquid-phases, water was chosen as an injection fluid. The steady-state process method was used to determine the permeability and relative permeability of unconsolidated sands to water flow. Different flow rates were measured for different pressure gradients in a viscose flow. As the flow rate increases, the pressure difference also increased. It can be observed that there are a direct correlation and relationship between the flow rate and the pressure difference. The core plug's absolute permeability was measured using Darcy Equation. Absolute permeability does not depend on fluid characteristics but only on media properties. The sample container contains a more significant amount of sand, decrease the permeability, and therefore requires high pressure for fluid flowing within the sample. [ABSTRACT FROM AUTHOR]

Porosity, permeability, and conductivity of PTMSP membranes in ethanol-water mixtures were determined by analyzing the impedance characteristics. The critical volume fraction of porosity at which through conductivity channels are formed was calculated. When the alcohol content in the solution increases, it was 0.29; when it decreases, it was 0.17. The obtained dependencies indicate that the transfer of matter in the membrane occurs the liquid phase elements, forming a percolation cluster as the amount of sorbed liquid increases. The hysteresis effect was observed in the measured values of porosity, permeability, conductivity, and capacity. The porous structure of a dry PTMSP membrane consists of free volume elements that are unconnected to each other. At ~30% alcohol concentration, through channels, begin to form, connecting both sides of the membrane. In this case, both permeability and electrical conductivity increase as a power function, in contrast to the porosity that increases linearly. Lichtenecker and Rother's formula helped to calculate the volume fractions of the conducting and non-conducting phases in the system. The obtained values of the amount of liquid in the membrane at various spatial arrangements of the channels made it possible to establish the structure of the liquid-filled channels. The best agreement with the experimental values was obtained for the chaotic structure. This is consistent with the existing ideas about the structure of the studied membranes and confirms the assumption that the percolation cluster is formed from free volume elements filled with the liquid phase. The observed low values of the zeta potential and, consequently, the low values of the electrostatic component of the wedging pressure indicate that the increase in the size or the number of transport channels is associated with non-electrostatic forces. [ABSTRACT FROM AUTHOR]

The fluid flow behavior should be known by reservoir engineers. This requires the application of techniques that help to achieve them. This is a very complex activity is therefore necessary to use tools such as statistics to perform the division of the tank into zones using record data and profiles of the wells. The technique used in this work is known for statistical zoning. From the use thereof it is possible to detect the different flow units. This study aims to estimate the flow units for an oil field wells and conduct a technical analysis defining the criteria to be evaluated to generate satisfactory results. Were used in this research data permeability seven wells located in the Field Boyfriend, whose data were provided by the National Petroleum Agency. Was calculated variance between potential areas grouped potential variances within these areas and, finally, the zoning index by which to define the end zones. According to the results obtained evidenced that the statistical zoning technique is satisfactory for the case study. [ABSTRACT FROM AUTHOR]

The erosion processes are natural phenomena that acts on soils and rocks to modify the land's relief and the soil type of the area is a factor that influences its occurrence and intensity. The erodibility is an index that explains the vulnerability of the soil to undergo an erosive process, relating the physical-chemical characteristics of the soil and / or the state of land cover. The work took place in a rural property, located in the District of Amadeu Amaral, in the city of Marília / SP and aimed at the physical analysis of the soil type, its classification and the soil permeability coefficient, in order to understand the relation between the recurrent erosive process and the soil characteristics. For this, morphological, textural and fractionation analyzes were performed using the methods of EMBRAPA (1997) and a soil permeability test. With the accomplishment of the work, it was perceived that the soil characteristics attribute to it great susceptibility to erosive processes, which contributed, along with the anthropic influences, to the acceleration of the erosion in the area. [ABSTRACT FROM AUTHOR]

The problem of energy supply has been one of the most pressing issues for the humanity at all times. Oil is one of the most desired sources of energy. However, oil reserves are being depleted, and substantial amounts of subterranean residual oil cannot be extracted with the use of traditional methods, therefore requiring implementation of new technologies. The current paper suggests two mathematical models aimed to describe and predict implications of microbiological method of oil recovery improvement based on the currently available data, as well as to assess the efficiency of this method. The first model consists of partial differential equations that describe the process of expansion of microbial population through oil formation. The second model includes ordinary differential equations, describing growth and metabolism of bacterial cultures within the bottom-hole zone of the production well. The models were studied with the use of numerical grid and Euler methods. The modeling parameters were evaluated using the least squares method. The current paper includes the results of calculations performed on basis of the proposed models. Distribution profiles of the bacterial population and the metabolic products along the reservoir were obtained and studied; provided recommendations for practical implementation of the microbiological method. [ABSTRACT FROM AUTHOR]

Use of environmental friendly materials has become subject of great scientific and commercial interest due to negative impact of synthetic plastics from petrochemical origin due to their inadequate final disposal, in that sense, blends of thermoplastic starch (TPS) and polylactic acid (PLA) have been studied in various applications. In this research flexible film was obtained from these polymers mixture, using blown extrusion process, where mechanical properties, oxygen barrier and water vapor were studied, in order to compare them with film containing polycaprolactone (PCL) in its formulation, trying to reduce costs of final product maintaining its mechanical and barrier properties. It was evidenced no significant differences among TPS/PLA blend with TPS/PLA/PCL blend, obtaining a high oxygen barrier material, with outstanding mechanical properties compared to other studies but poor water vapor permeability to plastics of synthetic origin. [ABSTRACT FROM AUTHOR]

In a theoretical point of view, the aim of our article is to reflect about the development of the competences, in a working context, starting from the study of the human activity and its conceptual organization in a social context. We point out two characteristics of activity; the changeable and the development. We start from this theory to question the planning of the practice of the nursing care, in the context of changing shifts. Planning is an activity of conceptualizing, constant adaptation to a specific context, elaborating and elaborating again the concepts, rules, past actions, in a present context. The planning activity placed in a specific context and when constructive, favors the development of abstraction. We suggest a formalization of the abstract development, articulating the macrogenetics and microgenetics of the planning activity, studied in a simulated situation of changing shifts and followed by the realization of a conceptual interview. [ABSTRACT FROM AUTHOR]

Petroleum reservoirs are sedimentary rocks with sufficient porosity and permeability to store and allow hydrocarbon flow. Testimonies of reservoir rocks are collected to be characterize and to obtain petrophysical data, for example, porosity and permeability. Currently, the characterization of reservoir rocks involves various analyzes such as optical and/or electron microscopy, porosity and permeability measurement using nitrogen gas injection, etc. These analyzes, although dedicated, time consuming, especially for the preparation of samples of the testimonies. In this scenario, the application of X-ray microtomography (MRX) by acquiring and processing three-dimensional images on the scale of the pores of the sample, usually requiring little or no preparation, allows the creation of a threedimensional digital model of the network pores and minerals associations for the study of lithological facies and their microstructures. This study proposes a procedure for acquiring and processing threedimensional images of reservoir rock samples obtained by MRX. The 3D nature of the data provides new perspectives for the evaluation of heterogeneity of rocks and simulation of flow in porous media. From the digital analysis of rocks, further studies can be carried out by applying the MRX as a tool for research studies sedimentological/diagenetic characterization of reservoir rock and analysis/modeling porosity and permeability. [ABSTRACT FROM AUTHOR]

Due to increased human settlement of the territory, the analysis of soil permeability of the basin appears as a variable to consider in studies of flood risk. To this effect, the methodology proposed by FAO to predict hydraulic behavior was applied to the soil. Said methodology has been validated by preceding studies focused on granulometry, porosity, and texture. The results made it possible to identify the basin's permeability zones. The size of the area made it necessary to use a GIS tool; however, this tool discards specific features which need to be incorporated into the measurement. [ABSTRACT FROM AUTHOR]

Films obtained from cassava starch variety CM 7138-7, native and modified by hydroxypropylation were subjected to mechanical evaluations, optical and barrier during periods of 0, 30, 60, 90 and 120 days by determining the effect of storage time on the chemical modification. The films were obtained by extrusion blowing using a single screw extruder. The material was obtained in three stages: the first stage was the production of Thermoplastic Starch (TPS) with 75% starch, 24,5% glycerol and 0,5% capsaicin; in the second step the Binary Mixture (MB) was made with 68,63 % of Polylactic Acid (PLA), 29,41% of Polycaprolactone (PCL), 1,96 % of maleic anhydride and 1 % of dye, and finally the blown extrusion of the ternary mixture, consisting of 75% of TPS and 25% of MB. Changes of some properties with time, were more evident in the films based on native starch, with significant difference, due to retrogradation process and possibly to a homogeneous phase in the material is not formed and therefore the components were divided into separate and distinct phases. [ABSTRACT FROM AUTHOR]

The goal of this research project was the optimization of a method for simultaneously screen the dissolution rate and the permeability of drug formulations across Polyvinylidene Fluoride membranes, using a bilateral flow cell. Initially, the effect of several variables was tested on caffeine and acetylsalicylic acid permeability. The obtained results showed that the method is more reproducible when the flow cell is used with unilateral flow at the donor side and with stirring on the acceptor side. It was also showed that the method is able to detect the influence of pH (caffeine Papp at pH 7,4 and 4,5: 4,84±1,57x10-5cm.s-1 and 6,00±0,70x10-5cm.s-1; acetylsalicylic acid Papp at pH 7,4 and 4,5: 3,85±0,38x10-5cm.s-1 and 5,11±0,65x10-5cm.s-1) and excipients (Papp of isolated caffeine and in the presence of excipients: 6,76±1,22x10-5cm.s-1 and 5,84±0,43x10-5cm.s-1; Papp of isolated acetylsalicylic acid and in the presence of excipients: 7,07±1,56 x 10-5cm.s-1 and 5,19±0,23x10-5cm.s-1) in drug permeability. A dissolution medium with pH 4.5, defined in the United States Pharmacopeia (USP) for caffeine/acetylsalicylic acid tablets, was used. Another biorelevant method was developed using a dissolution media with pH 7.4 due to the future goal of testing drugs permeability with Caco-2 cellular membranes. The dissolution percentages with this new media were of 96,3% for caffeine and 87,1% for the acetylsalicylic acid, higher then the 80% minimum limit described by the USP, making it possible to use this media in all the permeability assays. After the establishment of the isolated dissolution and permeability methodologies, the next step was the connection of both techniques. The dissolution/permeability assays were performed with a commercial pharmaceutical form containing both caffeine and acetylsalicylic acid (Melhoral®). The permeability results were reproducible and allowed discrimination between different media, opening therefore the possibility of its application in future works using cellular (Caco-2) or tissue (skin and intestinal) membranes. [ABSTRACT FROM AUTHOR]