Modeling Of District Metered Areas With Relatively High Leakage Rate. The Case Study Of Kalipoli’s DMA

The article reviews the modelling of District Metered Areas (DMAs) with relatively high leakage rate. As a generally recognised approach in modelling of leakage does not exist, modelling of leakage by enginners and other researchers usually takes place by dividing the whole leakage rate evenly to all available nodes of the model. In this article, a new methodology is proposed to determine the nodal leakage by using a hydraulic model. The proposed methodology takes into consideration the IWA water balance methodology, the Minimum Night Flow (MNF) analysis, the number of connections related to each node and the marerial of pipes. In addition, the model is illustrated by a real case study, as it was applied in Kalipoli’s DMA. Results show that the proposed model gives reliable results.

Modelagem e previsão da perda de injetividade em poços canhoneados

Waterflooding is a technique largely applied in the oil industry. The injected water displaces oil to the producer wells and avoid reservoir pressure decline. However, suspended particles in the injected water may cause plugging of pore throats causing formation damage (permeability reduction) and injectivity decline during waterflooding. When injectivity decline occurs it is necessary to increase the injection pressure in order to maintain water flow injection. Therefore, a reliable prediction of injectivity decline is essential in waterflooding projects. In this dissertation, a simulator based on the traditional porous medium filtration model (including deep bed filtration and external filter cake formation) was developed and applied to predict injectivity decline in perforated wells (this prediction was made from history data). Experimental modeling and injectivity decline in open-hole wells is also discussed. The injectivity of modeling showed good agreement with field data, which can be used to support plan stimulation injection wells

Estudo de sistemas multicomponentes no processo de injeção cíclica de vapor

In Brazilian Northeast there are reservoirs with heavy oil, which use steam flooding as a recovery method. This process allows to reduce oil viscosity, increasing its mobility and consequently its oil recovery. Steam injection is a thermal method and can occurs in continues or cyclic form. Cyclic steam stimulation (CSS) can be repeated several times. Each cycle consisting of three stages: steam injection, soaking time and production phase. CSS becomes less efficient with an increase of number of cycles. Thus, this work aims to study the influence of compositional models in cyclic steam injection and the effects of some parameters, such like: flow injection, steam quality and temperature of steam injected, analyzing the influence of pseudocomponents numbers on oil rate, cumulative oil, oil recovery and simulation time. In the situations analyzed was compared the model of fluid of three phases and three components known as Blackoil . Simulations were done using commercial software (CMG), it was analyzed a homogeneous reservoir with characteristics similar to those found in Brazilian Northeast. It was observed that an increase of components number, increase the time spent in simulation. As for analyzed parameters, it appears that the steam rate, and steam quality has influence on cumulative oil and oil recovery. The number of components did not a lot influenced on oil recovery, however it has influenced on gas production

Estudo paramétrico do processo de injeção de solventes em poços horizontais para reservatórios de óleos pesados

The world has many types of oil that have a range of values of density and viscosity, these are characteristics to identify whether an oil is light, heavy or even ultraheavy. The occurrence of heavy oil has increased significantly and pointing to a need for greater investment in the exploitation of deposits and therefore new methods to recover that oil. There are economic forecasts that by 2025, the heavy oil will be the main source of fossil energy in the world. One such method is the use of solvent vaporized VAPEX which is known as a recovery method which consists of two horizontal wells parallel to each other, with a gun and another producer, which uses as an injection solvent that is vaporized in order to reduce the viscosity of oil or bitumen, facilitating the flow to the producing well. This method was proposed by Dr. Roger Butler, in 1991. The importance of this study is to analyze how the influence some operational reservoir and parameters are important in the process VAPEX, such as accumulation of oil produced in the recovery factor in flow injection and production rate. Parameters such as flow injection, spacing between wells, type of solvent to be injected, vertical permeability and oil viscosity were addressed in this study. The results showed that the oil viscosity is the parameter that showed statistically significant influence, then the choice of Heptane solvent to be injected showed a greater recovery of oil compared to other solvents chosen, considering the spacing between the wells was shown that for a greater distance between the wells to produce more oil

Identificação e avaliação de propriedades de polissacarídeos sulfatados de diferentes fontes naturais que possibilitem sua aplicabilidade biotecnológica

Sulfated polysaccharides (SP) are widely distributed in animals and seaweeds tissues. These polymers have been studied in light of their important pharmacological activities, such as anticoagulant, antioxidant, antitumoral, anti-inflammatory, and antiviral properties. On other hand, SP potential to synthesize biomaterials like as nanoparticules has not yet been explored. In addition, to date, SP have only been found in six plants and all inhabit saline environments. However, the SP pharmacological plant activities have not been carrying out. Furthermore, there are no reports of SP in freshwater plants. Thus, do SP from marine plants show pharmacological activity? Do freshwater plants actually synthesize SP? Is it possible to synthesize nanoparticles using SP from seaweed? In order to understand this question, this Thesis was divided into tree chapters. In the first chapter a sulfated polysaccharide (SPSG) was successfully isolated from marine plant Halodule wrightii. The data presented here showed that the SPSG is a 11 kDa sulfated heterogalactan contains glucose and xylose. Several assays suggested that the SPSG possessed remarkable antioxidant properties in different in vitro assays and an outstanding anticoagulant activity 2.5-fold higher than that of heparin Clexane® in the aPTT test; in the next chapter using different tools such as chemical and histological analyses, energy-dispersive X-ray analysis (EDXA), gel electrophoresis and infra-red spectroscopy we confirm the presence of sulfated polysaccharides in freshwater plants for the first time. Moreover, we also demonstrate that SP extracted from E. crassipes root has potential as an anticoagulant compound; and in last chapter a fucan, a sulfated polysaccharide, extracted from the brown seaweed was chemically modified by grafting hexadecylamine to the polymer hydrophilic backbone. The resulting modified material (SNFuc) formed nanosized particles. The degree of substitution for hydrophobic chains of 1H NMR was approximately 93%. SNFfuc-TBa125 in aqueous media had a mean diameter of 123 nm and zeta potential of -38.3 ± 0.74 mV, measured bydynamic light scattering. Tumor-cell (HepG2, 786, H-S5) proliferation was inhibited by 2.0 43.7% at SNFuc concentrations of 0.05 0.5 mg/ mL and RAEC non-tumor cell line proliferation displayed inhibition of 8.0 22.0%. On the other hand, nanogel improved CHO and RAW non-tumor cell line proliferation in the same concentration range. Flow cytometric analysis revealed that this fucan nanogel inhibited 786 cell proliferation through caspase and caspaseindependent mechanisms. In addition, SNFuc blocks 786 cell passages in the S and G2-M phases of the cell cycle

Um sistema para estimação da vazão de gás de poços produzindo por Plunger Lift para vaso separador de teste em plataformas de petróleo

This work intends to analyze the behavior of the gas flow of plunger lift wells producing to well testing separators in offshore production platforms to aim a technical procedure to estimate the gas flow during the slug production period. The motivation for this work appeared from the expectation of some wells equipped with plunger lift method by PETROBRAS in Ubarana sea field located at Rio Grande do Norte State coast where the produced fluids measurement is made in well testing separators at the platform. The oil artificial lift method called plunger lift is used when the available energy of the reservoir is not high enough to overcome all the necessary load losses to lift the oil from the bottom of the well to the surface continuously. This method consists, basically, in one free piston acting as a mechanical interface between the formation gas and the produced liquids, greatly increasing the well s lifting efficiency. A pneumatic control valve is mounted at the flow line to control the cycles. When this valve opens, the plunger starts to move from the bottom to the surface of the well lifting all the oil and gas that are above it until to reach the well test separator where the fluids are measured. The well test separator is used to measure all the volumes produced by the well during a certain period of time called production test. In most cases, the separators are designed to measure stabilized flow, in other words, reasonably constant flow by the use of level and pressure electronic controllers (PLC) and by assumption of a steady pressure inside the separator. With plunger lift wells the liquid and gas flow at the surface are cyclical and unstable what causes the appearance of slugs inside the separator, mainly in the gas phase, because introduce significant errors in the measurement system (e.g.: overrange error). The flow gas analysis proposed in this work is based on two mathematical models used together: i) a plunger lift well model proposed by Baruzzi [1] with later modifications made by Bolonhini [2] to built a plunger lift simulator; ii) a two-phase separator model (gas + liquid) based from a three-phase separator model (gas + oil + water) proposed by Nunes [3]. Based on the models above and with field data collected from the well test separator of PUB-02 platform (Ubarana sea field) it was possible to demonstrate that the output gas flow of the separator can be estimate, with a reasonable precision, from the control signal of the Pressure Control Valve (PCV). Several models of the System Identification Toolbox from MATLAB® were analyzed to evaluate which one better fit to the data collected from the field. For validation of the models, it was used the AIC criterion, as well as a variant of the cross validation criterion. The ARX model performance was the best one to fit to the data and, this way, we decided to evaluate a recursive algorithm (RARX) also with real time data. The results were quite promising that indicating the viability to estimate the output gas flow rate from a plunger lift well producing to a well test separator, with the built-in information of the control signal to the PCV

Cell cycle arrest evidence, parasiticidal and bactericidal properties induced by L-amino acid oxidase from Bothrops atrox snake venom

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

Development and In Vitro Evaluation of Surfactant Systems for Controlled Release of Zidovudine

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise citogenética de células-tronco derivadas do subendotélio da veia umbilical humana

Mesenchymal stem cells (MSCs) are known as a population of multi-potential cells able to proliferate and differentiate into multiple mesodermal tissues including bone, cartilage, muscle, ligament, tendon, fat and stroma. Several applications of the study of EC can be emphasized the therapeutic techniques such as guided bone regeneration by implantation of EC in the affected site, without the need for bone grafts, using titanium as a vehicle. The process of cryopreservation is essential for the maintenance of cell cultures, since the cell line is frozen, it can be maintained in liquid nitrogen for an indefinite period and then thawed for therapeutic or experimental purposes. The aim of this study was to isolate a population of MSCs derived from the subendothelium of the umbilical vein human (MSCs-SUVH) to assess cytogenetic analysis by the possibility of appearance of chromosomal changes in two different situations: MSCs-SUVH regarding the process of cryopreservation and MSCs-SUVH grown on the surface of titanium. Flow cytometry analysis revealed that, this cell population was positive for the markers CD29, CD73 and CD90, but there was no expression of hematopoietic lineage markers, such as CD14, CD34 and CD45 and demonstrated capacity for osteogenic differentiation. The chromosomes obtained from the primary culture of MSCs-SUVH were analyzed by GTW banding technique, and results are described as guidelines to ISCN 2005. There was not the emergence of clonal chromosomal changes in the MSCs-SUVH in different situations analyzed. However one of the strings presented a balanced paracentric inversion, probably a cytogenetic constitutional alterations, which was present before and after the experimental situations that the MSCs-SUVH was submitted

Pollen Dispersal Between Isolated Trees in the Brazilian Savannah: A Case Study of the Neotropical Tree Hymenaea stigonocarpa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Periodontal Tissue Engineering After Tooth Replantation

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

Determination of Cd(II), Cu(II) and Ni(II) in aqueous samples by ICP-OES after on-line preconcentration in column packed with silica modified with 2-aminothiazole

This work describes the synthesis and characterization of 2-aminothiazole modified silica gel (SiAT) and the studies of adsorption and pre-concentration (in batch and using a flow-injection system coupled with optical emission spectrometer) of Cd(II), Cu(II) and Ni(II) in aqueous medium. The adsorption capacity for each metal ions in mmolg(-1) was: Cu(II) = 1.18, Ni(II) = 1.15 and Cd(II) = 1.10. The results obtained in the flow experiments showed about 100% of recovering of the metal ions adsorbed in a mini-column packed with 100 mg of SiAT, using 100 mu L of 2.0 mol L-1 HCl solution as eluent. The quantitative sorption-desorption of the metal ions made possible the application of a flow-injection system in the pre-concentration and quantification by ICP-OES of metal ions at trace level in natural water samples.

Prevention of experimental diabetes by Uncaria tomentosa extract: Th2 polarization, regulatory T cell preservation or both?

Ethnopharmacological relevance: Uncaria tomentosa (Willd.) DC (Rubiaceae) is a species native to the Amazon rainforest and surrounding tropical areas that is endowed with immunomodulatory properties and widely used around the world. In this study we investigated the immunomodulatory potential of Uncaria tomentosa (UT) aqueous-ethanol extract on the progression of immune-mediated diabetes.Materials and methods: C57BL/6 male mice were injected with MLDS (40 mg/kg) and orally treated with UT at 10-400 mg/kg during 21 days. Control groups received MLDS alone or the respective dilution vehicle. Pancreatic mononuclear infiltrate and beta-cell insulin content were analyzed by HE and immunohistochemical staining, respectively, and measured by digital morphometry. Lymphocyte immunophenotyping and cytokine production were determined by flow cytometry analysis.Results: Treating the animals with 50-400 mg/kg of UT caused a significant reduction in the glycemic levels, as well as in the incidence of diabetes. The morphometric analysis of insulitis revealed a clear protective effect. Animals treated with UT at 400 mg/kg presented a higher number of intact islets and a significant inhibition of destructive insulitis. Furthermore, a significant protection against the loss of insulin-secreting presented beta-cells was achieved, as observed by a careful immunohistochemical evaluation. The phenotypic analysis indicated that the groups treated with higher doses (100-400 mg/kg) presented CD4(+) and CD8(+) T-cell values similar to those observed in healthy animals. These same higher doses also increased the number of CD4(+)CD25(+)Foxp3(+) regulatory T-cells. Moreover, the extract modulated the production of Th1 and Th2, with increased levels of IL-4 and IL-5.Conclusions: The extract was effective to prevent the progression of immune-mediated diabetes by distinct pathways. (C) 2011 Elsevier B.V. All rights reserved.

Developmental exposure to diuron causes splenotoxicity in male Sprague-Dawley rat pups

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

In vitro study of CD133 human stem cells labeled with superparamagnetic iron oxide nanoparticles

Superparamagnetic iron oxide nanoparticles (SPIONs) are applied in stem cell labeling because of their high magnetic susceptibility as compared with ordinary paramagnetic species, their low toxicity, and their ease of magnetic manipulation. The present work is the study of CD133(+) stem cell labeling by SPIONs coupled to a specific antibody (AC133), resulting in the antigenic labeling of the CD133+ stem cell, and a method was developed for the quantification of the SPION content per cell, necessary for molecular imaging optimization. Flow cytometry analysis established the efficiency of the selection process and helped determine that the CD133 cells selected by chromatographic affinity express the transmembrane glycoprotein CD133. The presence of antibodies coupled to the SPION, expressed in the cell membrane, was observed by transmission electron microscopy. Quantification of the SPION concentration in the marked cells using the ferromagnetic resonance technique resulted in a value of 1.70 x 10 (13) mol iron (9.5 pg) or 7.0 x 10 (6) nanoparticles per cell ( the measurement was carried out in a volume of 2 mu L containing about 6.16 x 10 5 pg iron, equivalent to 4.5 x 10 (11) SPIONs). (c) 2008 Elsevier B.V. All rights reserved.