90 resultados para Decomposição


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The field of Wireless Sensor and Actuator Networks (WSAN) is fast increasing and has attracted the interest of both the research community and the industry because of several factors, such as the applicability of such networks in different application domains (aviation, civil engineering, medicine, and others). Moreover, advances in wireless communication and the reduction of hardware components size also contributed for a fast spread of these networks. However, there are still several challenges and open issues that need to be tackled in order to achieve the full potential of WSAN usage. The development of WSAN systems is one of the most relevant of these challenges considering the number of variables involved in this process. Currently, a broad range of WSAN platforms and low level programming languages are available to build WSAN systems. Thus, developers need to deal with details of different sensor platforms and low-level programming abstractions of sensor operational systems on one hand, and they also need to have specific (high level) knowledge about the distinct application domains, on the other hand. Therefore, in order to decouple the handling of these two different levels of knowledge, making easier the development process of WSAN systems, we propose LWiSSy (Domain Language for Wireless Sensor and Actuator Networks Systems), a domain specific language (DSL) for WSAN. The use of DSLs raises the abstraction level during the programming of systems and modularizes the system building in several steps. Thus, LWiSSy allows the domain experts to directly contribute in the development of WSANs without having knowledge on low level sensor platforms, and network experts to program sensor nodes to meet application requirements without having specific knowledge on the application domain. Additionally, LWiSSy enables the system decomposition in different levels of abstraction according to structural and behavioral features and granularities (network, node group and single node level programming)

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Collembola is one of the most abundant and diverse group of terrestrial arthropods, being at the base of the food chain operating in the decomposition process. They have a wide distribution in the world and can be found in practically all habitats. The knowledge of this distinctive fauna is still deficient in brazilian territory, especially in semi-arid region. The aim of this study was to investigate which climatic variables may act as predictors of species richness, abundance of individuals and compositional structure of the taxocenose of Collembola over 12 months in an area dominated by semi-arid Caatinga vegetation, northeastern Brazil and describe new species of the genus Seira found, more diverse taxon of Collembola in Brazil. Samples were collected in João Câmara, Rio Grande do Norte. Ten plots of 20 x 20 meters were established and the specimens were collected with collection effort of one hour/people using entomological aspirator. The identification and description of the species was carried out by studying the morphology and chaetotaxy. Was performed a multiple regression analysis between species richness and abundance of individuals with climatic variables. A total of 1231 individuals belonging to 15 species, 12 genera and nine families. The greatest richness and abundance of Collembola were found during the rainy season. The genus Seira was the most abundant. Rainfall explained the temporal variation in species richness and abundance of Collembola in the semi-arid region, which is consistent with the biology of these animals. The populations of Collembola showed grouped distribution. Three new species of Seira were described and illustrated and all show similarities with species already registered in the national territory

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Nowadays, as well as in the past decades, the dumping of biodegradable organic waste in landfill is common practice in Brazil, as well as in most parts of the world. Nevertheless due to its rapid decomposition and release of odors, this practice hamper’s the operation and implementation of a recycling system. These facts encouraged our research to find an efficient system for the management of organic waste, not only for the use of official workers responsible for managing these wastes, but also for non-governmental institutions. The Recycling for Life Community Association – ACREVI (Associação Comunitária Reciclando para a Vida), together with the municipal authorities of Mossoró-RN, Brazil, have assumed the social role of collecting and recycling solid waste produced by most of the local population. However, it was observed that the organic waste it collected was not receiving any treatment. This present work aims to make compost with mixed waste (green waste and organic household), and then do chemical analysis of the material in view to use the waste as organic fertilizer. The objective being: to share the knowledge acquired by putting it into a very simple language accessible to people with little education. The experiment was conducted at ACREVI, Mossoró (RN), and the compost was obtained following the method "windrow", forming three cells (I, II, III) with conical shape, dimensions of 1.6 meters and 2.0 meters in diameter for cells I and II, and 1.0 meters high and 2.0 meters in diameter for cell III. The process was accompanied by analysis: CHN elemental, a variation of cell temperature, humidity, pH, TKN, bulk density, nutrients and heavy metals. Stabilized organic compounds reached the C/N ratio of 10.4/1 cell I and 10.4/1 in the cell II in the cell, showing how good soil conditions, with potential to improve the physical properties of any soil and pH acid soils, has presented the cell III at the end of the process the C/N 26/1, is a high ratio may be associated with the stack size III, thus changing the optimal conditions for the occurrence of the process. The levels of heavy metals in the analyzed compounds were lower than those established by the SDA normative instruction, Nº 27, of 5 June, 2006. The use of pruning trees and grass are used in small-scale composting, while generating a quality compost in the final process, it also created an important condition for a correct sizing of the composting piles. Under the studied conditions it is not advisable to use cells with a height of 1.00 m in height and 2.00 m in diameter, as these do not prevent the rapid dissipation of heat and thus can not be a good product at the end of composting. The composting process in the shed of the association and the preparation of the primer enabled the development of an alternative technology to generate income for members of ACREVI.

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In this work, the reference drugs, generic and similar to the active ingredients acetylsalicylic acid, paracetamol, captopril, hydrochlorothiazide and mebendazole were purchased from local pharmacies and studied by thermogravimetry (TG) and Differential Scanning Calorimetry (DSC). Thermal decomposition was assessed to obtain from the Ozawa method the activation energy in inert atmosphere (nitrogen), using three different heating ratios (5, 10 and 20 o C min-1). The pharmaceutical formulation of the AAS reference was the one who presented different from the others (generic and similar) Thermogravimetric profile indicating likely interaction between the active ingredient and excipients. Was observed at the heating rate of the inverse temperature that no linearity of the data, ie, there was no correlation between the percentage of mass loss and the activation energy involved in the thermal decomposition of the pharmaceutical formulation of the AAS reference log graph. The analysis by differential scanning calorimetry was performed in nitrogen atmosphere with a heating rate of 10 ° C min-1. In the analysis of these same drugs, the data curves found on the melting point were, except for hydrochlorothiazide, are consistent with the literature. Hydrochlorothiazide presented a melting point well below that found in the literature, which may be justified due to the interaction of the active ingredient with the excipient lactose. In the study of purity, using the Van't Hoff equation, the reference drugs hydrochlorothiazide and mebendazole reference generic and showed similar impurity content below the limit established that this equation must be greater than 2.5 mol%

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The Cu-Mo system is a composite used in the electrical industry as material for electrical contact and resistance welding electrode as well as the heat sink and microwave absorber in microelectronic devices. The use of this material in such applications is due to the excellent properties of thermal and electrical conductivity and the possibility of adjustment of its coefficient of thermal expansion to meet those of materials used as substrates in the semiconductor micoreletrônic industry. Powder metallurgy through the processes of milling, pressing shaping and sintering is a viable technique for consolidation of such material. However, the mutual insolubility of both phases and the low wettability of liquid Cu on Mo impede its densification. However, the mutual insolubility of both phases and the low wettability of liquid Cu on Mo impede its densification. The mechanical alloying is a technique for preparation of powders used to produce nanocrystalline composite powder with amorphous phase or extended solid solution, which increases the sinterability immiscible systems such as the Mo-Cu. This paper investigates the influence of ammonium heptamolybdate (HMA) and the mechanical alloying in the preparation of a composite powder HMA-20% Cu and the effect of this preparation on densification and structure of MoCu composite produced. HMA and Cu powders in the proportion of 20% by weight of Cu were prepared by the techniques of mechanical mixing and mechanical alloying in a planetary mill. These were milled for 50 hours. To observe the evolution of the characteristics of the particles, powder samples were taken after 2, 10, 15, 20, 30 and 40 hours of milling. Cylindrical samples 5 to 8 mm in diameter and 3 to 4 mm thickness were obtained by pressing at 200 MPa to the mixed powders so as to ground. These samples were sintered at 1200 ° C for 60 minutes under an atmosphere of H2. To determine the effect of heating rate on the structure of the material during the decomposition and reduction of HMA, rates of 2, 5 and 10 ° C / min were used .. The post and the structures of the sintered samples were characterized by SEM and EDS. The density of the green and sintered bodies was measured using the geometric method (weight / volume). Vickers microhardness with a load of 1 N for 15 s were performed on sintered structures. The density of the sintered structures 10 ° C / min. reached 99% of theoretical density, how the density of sintered structures to 2 ° C / min. reached only 90% of the theoretical density

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The contamination of water sources of public drinking by waste originated by anthropogenic activities has brought various risks to human health. Among the consequences of such activities can highlight the bloom of microalgae and cyanobacteria, which have the potential to produce toxins dangerous to humans, and the presence of humic substances that are generated by the decomposition of natural organic matter (NOM), such as vegetation. When found in water sources for public supply, present negative aspects conferring high color, odor and taste. The double filtration technology has good efficiency in water with the presence of cyanobacteria and different quality variations. Therefore, this study aimed to evaluate the behavior of the technique of double filtration with pre-oxidation for water purifiers the lagoon of Extremoz-RN, which currently has high concentrations of cyanobacteria. The research is summarized in four phases: the first phase turned to static tests in jarteste equipment in the laboratory and subsequent phases were tested in the Pilot Plant of Double Filtration. For the second and third stage filtration rates were tested filtration rates of 120 and 180 m3 / m2 .day for ascending boulders filters and 160 and 240 m3 / m2 .day in the filters in quick sand descendants. The last phase aimed to evaluate the double filtration with pre-oxidation. The results demonstrated that the system could produce double filtration in all trials of good quality water according to the Decree nº. 2914/11 of the Ministry of Health. The use of preoxidation favored the removal of microcystin and color at the end of the tests, reaching a percentage of color removal around 60%. The analysis of variance in the data, enabled prove that the filtration rates of 180 m3 / m2.d the gravel filter and 240 m3 /m2 .d in rapid filters, were the most significant for the removal of turbidity. The ascending filter of boulder 4 with particle size finer filter layer showed the best performance and the best means of turbidity and apparent color. The rapid filter downward 1 was more efficient in removing turbidity reaching removal about 100%

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In this study we evaluated the capacity removal of PAHs in an oily solution between the bentonite hydrofobized with linseed oil and paraffin with natural bentonite. Analyses of natural bentonite and hydrofobized were made by the characterization techniques: (1) Thermogravimetric Analysis (TGA), which aimed to evaluate the thermal events due to mass loss, both associated with the exit of moisture and decomposition of clay as due to hidrofobizante loss agent. (2) Analysis of X-ray diffraction (XRD) in order to determine the mineralogical phases that make up the structure of clay and (3) Spectrophotometry in the infrared region used to characterize the functional groups of both the matrix mineral (bentonite) and the hidrofobizantes agents (linseed oil and paraffin). We used a factorial design 24 with the following factors; hidrofobizante, percent hidrofobizante, adsorption time and volume of the oily solution. Analyzing the factorial design 24 was seen that none of the factors apparently was more important than the others and, as all responses showed significant values in relation to the ability of oil removal was not possible to evaluate a difference in the degree of efficiency the two hidrofobizantes. For the new study compared the efficiency of the modified clay, with each hidrofobizante separately in relation to their natural form. As such, there are four new factorial designs 23 using natural bentonite as a differentiating factor. The factors used were bentonite (with and without hydrophobization), exposure time of the adsorbent material to the oily solution and volume of an oily solution, trying to interpret how these factors could influence the process of purifying water contaminated with PAHs. Was employed as a technique for obtaining responses to fluorescence spectroscopy, as already known from literature that PAHs, for presenting combined chains due to condensation of the aromatic rings fluoresce quite similar when excited in the ultraviolet region and as an auxiliary technique to gas chromatography / mass spectrometry (GC-MS) used for the analysis of PAHs in order to complement the study of fluorescence spectroscopy, since the spectroscopic method only allows you an idea of total number of fluorescent species contained in the oil soluble. The result shows an excellent adsorption of PAHs and other fluorescent species assigned to the main effect of the first factor, hydrophobization for the first planning 23 BNTL 5%, for 93% the sixth stop in the second test (+-+),factorial design 23 BNTL 10%, the fourth test (++-) with 94.5% the third factorial design 23 BNTP 5%, the second test (+--) with 91% and the fourth and final planning 23 BNTP 10%, the last test ( + + +) with 88%. Compared with adsorption of bentonite in its natural form. This work also shows the maximum adsorption of each hidrofobizante

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This work aimed to promote the synthesis, characterization and propose a plausible molecular structure for coordination compounds involving furosemide (4-Chloro-2-(2- furylmethylamino)-5-sulfamoyl-benzoic acid) with the metal ions Ni+2, Zn+2 and Co+2. The compounds were obtained in methanoic medium by evaporation of the solvent after the synthesis procedure. For characterization of coordination compounds determining the levels of metals by EDTA complexometry, infrared spectroscopy (FTIR), solubility of compounds in various solvents, thermogravimetry (TG), differential scanning calorimetry (DSC), differential thermal analysis were made (DTA), determination of the carbon , hydrogen and nitrogen (CHN). The results of infrared spectroscopy in the region suggest that the organic ligand is coordinated in a bidentate fashion to the metal ions, the metal center interactions to occur by the coordination of the nitrogen atom of the amino group and the oxygen atom of the carboxylic acid of the structure of furosemide. With the results of the levels of metal, elemental analysis (CHN) and thermal analysis has been possible to propose the structure of the ligand. The values of the molar conductivity of the complex in acetonitrile behavior suggest the non acetonitrile electrolyte solution. With the solubility tests it was found that the compounds have high solubility in methanol and acetonitrile, as are partially insoluble in water. From the results of thermal analysis (TG, DSC, DTA), it was possible to obtain the thermal behavior of the compounds as stages of dehydration, thermal stability, decomposition and the energies involved.

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Os recentes avanços técnicos das duas últimas décadas para o registro de sinais neuroeletrofisiológicos foram essenciais para que se testassem hipóteses há muito propostas acerca de como células nervosas processam e armazenam informação. No entanto, ao permitir maior detalhamento dos dados coletados, as novas tecnologias levam inevitavelmente ao aumento de sua complexidade estatística e, consequentemente, à necessidade de novas ferramentas matemático-computacionais para sua análise. Nesta tese, apresentamos novos métodos para a análise de dois componentes fundamentais nas atuais teorias da codificação neural: (1) assembleias celulares, definidas pela co-ativação de subgrupos neuronais; e (2) o padrão temporal de atividade de neurônios individuais. Em relação a (1), desenvolvemos um método baseado em análise de componentes independentes para identificar e rastrear padrões de co-ativação significativos com alta resolução temporal. Superamos limitações de métodos anteriores, ao efetivamente isolar assembleias e abrir a possibilidade de analisar simultaneamente grandes populações neuronais. Em relação a (2), apresentamos uma nova técnica para a extração de padrões de atividade em trens de disparo baseada na decomposição wavelet. Demonstramos, por meio de simulações e de aplicação a dados reais, que nossa ferramenta supera as mais utilizadas atualmente para decodificar respostas de neurônios e estimar a informação de Shannon entre trens de disparos e estímulos externos.

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The sabiá (Mimosa caesalpiniaefolia Benth.) is an endemic species of the Caatinga biome, considered tolerant to salt and water stress. The process of salinization of soil and groundwater and surface water is one of the most important problems of environmental degradation, with its harmful effects being more pronounced in the areas of arid and semiarid regions, and rapidly growing in many parts of the globe, causing problems of the major crop yield. Organic conditioners as barnyard manure, and rice hulls can contribute to reducing the PST, possibly due to the release of CO2 and the production of organic acids during the decomposition of organic matter, and act as sources of calcium and magnesium and inhibit the availability sodium. The intimate association of mycorrhizae and beneficial to plants results in increased uptake of water and nutrients by plants, especially phosphorus, due to their low mobility in soil. The objective of this study was to evaluate the initial growth of thrush seedlings under inoculation with mycorrhizal fungi and fertilized with manure corral and irrigated with water of different salinity levels. The experiment was conducted in greenhouse conditions of vegetation on the premises of the Agricultural School of Jundiaí - UFRN, Campus Macaíba. The adopted statistical design was randomized composed of twelve treatments - three substrates (sterile soil, manure and FMA), four salinity levels (0.2, 1.5, 3.0 and 4.5 dS m-1 ) and five repetitions, totaling sixty experimental units. The results indicate that inoculation with mycorrhizal fungi own contributions to the growth of plants, especially in roots and shoots, which suggests that its application is beneficial in establishing thrush plants in natural conditions, with poor soil in P. Levels salinity caused no effects with statistical significance in plant development, indicating Sabia resistance to it.

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We present indefinite integration algorithms for rational functions over subfields of the complex numbers, through an algebraic approach. We study the local algorithm of Bernoulli and rational algorithms for the class of functions in concern, namely, the algorithms of Hermite; Horowitz-Ostrogradsky; Rothstein-Trager and Lazard-Rioboo-Trager. We also study the algorithm of Rioboo for conversion of logarithms involving complex extensions into real arctangent functions, when these logarithms arise from the integration of rational functions with real coefficients. We conclude presenting pseudocodes and codes for implementation in the software Maxima concerning the algorithms studied in this work, as well as to algorithms for polynomial gcd computation; partial fraction decomposition; squarefree factorization; subresultant computation, among other side algorithms for the work. We also present the algorithm of Zeilberger-Almkvist for integration of hyperexpontential functions, as well as its pseudocode and code for Maxima. As an alternative for the algorithms of Rothstein-Trager and Lazard-Rioboo-Trager, we yet present a code for Benoulli’s algorithm for square-free denominators; and another for Czichowski’s algorithm, although this one is not studied in detail in the present work, due to the theoretical basis necessary to understand it, which is beyond this work’s scope. Several examples are provided in order to illustrate the working of the integration algorithms in this text

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Reservoirs are artificial ecosystems intermediate between rivers and lakes widely used in the Brazilian semiarid region as a way to provide water supply due to the said region’s water scarcity. The use of water from these supply sources for multiple uses, along with occupation and utilization of its riparian zone without proper management, directly influences the increased nutrient flow into aquatic environments, there with contributing to the acceleration of eutrophication. The semi-arid region is characterized by peculiar weather conditions, such as severe evaporation, high temperatures with little variation throughout the year and long water residence time, making it susceptible to prolonged drought occurrence, which tends to concentrate the nutrients in reservoirs, which favors the development of eutrophic conditions. Moreover, it is common soil use and occupation by carrying out activities with potential environmental impact on natural resources such as agriculture, livestock farming and lack of sanitation. The aim of this study is both to evaluate the water quality of the Cruzeta Reservoir, located in the semiarid region of Rio Grande do Norte, during a prolonged drought period, and assess the quality of its riparian zone soil under different uses, by monitoring physical-chemical variables. Along the prolonged drought, high levels of turbidity, suspended solids, nutrients and chlorophyll a were verified as present, therefore featuring low water quality. In the riparian zone of Cruzeta Reservoir, the areas under use of agriculture and livestock farming appeared as one of the main diffuse sources of nutrients to the said reservoir, featuring the highest levels of phosphorus and nitrogen in the soil, originated from decomposition of animal excreta and from the use of fertilizers, creating a tendency to increased eutrophication of such water supply source. The indicators of water and soil quality are useful for monitoring and evaluating the conservation status of natural resources, allowing the control and mitigation of the reservoir eutrophication process. This study confirmed the hypothesis that the reduction of water level, resulting from prolonged drought event, aggravates the symptoms of eutrophication; and also that using the soil under severalways modifies the physic chemical properties of the soil, having livestock farming and agriculture as the usages with greatest potential towards yielding P and N to the aquatic environment.

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Trace gases are important to our environment even though their presence comes only by ‘traces’, but their concentrations must be monitored, so any necessary interventions can be done at the right time. There are some lower and upper boundaries which produce nice conditions for our lives and then monitoring trace gases comes as an essential task nowadays to be accomplished by many techniques. One of them is the differential optical absorption spectroscopy (DOAS), which consists mathematically on a regression - the classical method uses least-squares - to retrieve the trace gases concentrations. In order to achieve better results, many works have tried out different techniques instead of the classical approach. Some have tried to preprocess the signals to be analyzed by a denoising procedure - e.g. discrete wavelet transform (DWT). This work presents a semi-empirical study to find out the most suitable DWT family to be used in this denoising. The search seeks among many well-known families the one to better remove the noise, keeping the original signal’s main features, then by decreasing the noise, the residual left after the regression is done decreases too. The analysis take account the wavelet decomposition level, the threshold to be applied on the detail coefficients and how to apply them - hard or soft thresholding. The signals used come from an open and online data base which contains characteristic signals from some trace gases usually studied.

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Trace gases are important to our environment even though their presence comes only by ‘traces’, but their concentrations must be monitored, so any necessary interventions can be done at the right time. There are some lower and upper boundaries which produce nice conditions for our lives and then monitoring trace gases comes as an essential task nowadays to be accomplished by many techniques. One of them is the differential optical absorption spectroscopy (DOAS), which consists mathematically on a regression - the classical method uses least-squares - to retrieve the trace gases concentrations. In order to achieve better results, many works have tried out different techniques instead of the classical approach. Some have tried to preprocess the signals to be analyzed by a denoising procedure - e.g. discrete wavelet transform (DWT). This work presents a semi-empirical study to find out the most suitable DWT family to be used in this denoising. The search seeks among many well-known families the one to better remove the noise, keeping the original signal’s main features, then by decreasing the noise, the residual left after the regression is done decreases too. The analysis take account the wavelet decomposition level, the threshold to be applied on the detail coefficients and how to apply them - hard or soft thresholding. The signals used come from an open and online data base which contains characteristic signals from some trace gases usually studied.

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Were synthesized in this work in the following aqueous solution coordination compounds: [Ni(LDP)(H2O)2Cl2].2H2O, [Co(LDP)Cl2].3H2O, [Ni(CDP)Cl2].4H2O, [Co(CDP)Cl2].4H2O, [Ni(BDZ)2Cl2].4H2O and [Co(BDZ)2Cl2(H2O)2]. These complexes were synthesized by stoichiometric addition of the binder in the respective metal chloride solutions. Precipitation occurred after drying the solvent at room temperature. The characterization and proposed structures were made using conventional analysis methods such as elemental analysis (CHN), absorption spectroscopy in the infrared Fourier transform spectroscopy (FTIR), X-ray diffraction by the powder method and Technical thermoanalytical TG / DTG (thermogravimetry / derivative thermogravimetry) and DSC (differential scanning calorimetry). These techniques provided information on dehydration, coordination modes, thermal performance, composition and structure of the synthesized compounds. The results of the TG curve, it was possible to establish the general formula of each compound synthesized. The analysis of X-ray diffraction was observed that four of the synthesized complex crystal structure which does not exhibit the complex was obtained from Ldopa and carbidopa and the complex obtained from benzimidazole was obtained crystal structures. The observations of the spectra in the infrared region suggested a monodentate ligand coordination to metal centers through its amine group for all complexes. The TG-DTG and DSC curves provide important information and on the behavior and thermal decomposition of the synthesized compounds. The molar conductivity data indicated that the solutions of the complexes formed behave as a nonelectrolyte, which implies that chlorine is coordinated to the central atom in the complex.