60 resultados para Fontes documentais


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Dans ce texte, nous prenons avec probleme le départment bresilien de Piauí comme espacialité de la Région « Nordeste », suivant les instants de son insertion politique et discursif dans l'identité régionale, qui s'est donnée entre la fin des années 1950 et débuts des années 1970. Pour ceci, nous proposons une analyse de discours identitaires de Piauí comme la littérature et le folklore produits alors, cherchant à rapporter telles discours avec les pratiques et intérêts politiques qui ont concouru pour la « nordestinization » de Piauí. Parmi ces discours et dans dialogue avec eux, nous prenons centralement l'oeuvre du juge et ecrivain João Nonon de Moura Fontes Ibiapina, emisseur de signes qui apparaît en ce moment. Notre objectif est discuter les images élaborées sur Piauí et son inclusion dans les stéréotypes cristallisés de Nordeste, comme la pauvreté et la nécessité, la vie dans le champs et la prédominance d'une « culture populaire » régionale. Dans une période d'importantes mutations dans la société brésilienne, dans la production culturelle, dans heurtes régionalistes Nordeste et dans les formes de penser et pratiquer les espaces, les intellectuels de Piauí que nous étudions ont essayé de recouvrir de mots et de sens la noirceur et l'incommode silence concernant le Piauí dans la Nation bresilienne, quand le déparment s'intégrait, au moyen de la Région, au Brésil urbain et industrialisé

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Founded in 1536, the Court of the Holy Office of the Portuguese Inquisition was established as an ecclesiastical institution, but at the same time subordinate to the real powers. Among the main victims of persecution effected by the Holy Office, were the New Christians - Jews forcibly converted in 1497 or their descendants - that due to their socio-religious were repeatedly accused of heresy. This paper conducted a survey that sought to understand the historical performance of the Inquisition in Brazil in the sixteenth century on the New Christians, especially those accused of secretly retaining the religious customs of the Mosaic law, given the investigative and punitive procedures employed by the Inquisition as part of a set of actions that produce social insecurities and producers / broadcasters of fear in the populations under scrutiny. In this sense, the approach was based on the analysis of documents produced on the first visit of inspection performed in Brazil inquisitorial sixteenth century, concerning the captaincy of Pernambuco and Paraiba Itamaracá (1593-1595), not excluding, however, the sources of the first stage of visitation that occurred between 1591-1593 in the province of Bahia de Todos os Santos, even though its use is ancillary and punctual. The objective of this research was to understand the consequences of inquisitorial procedures generated on the imaginary, and the Inquisition, using the expressions and signs of fears relating to individuals contained in the New Christian complaints to the Holy Office as documentary evidence of the fear caused by the Holy Tribunal. The adoption of specific behaviors by the New Christians in the home - these spaces are appropriate and adapted to the detriment of the religious practices of Judaism features - characterizes the spatial perspective of the study, thus indicating a further objective of the study: to understand how the New Christians experienced domestic spaces in a historical context marked by behavioral surveillance generally considered morally condemned and suspected of heresy. The research was conducted to analyze the complaints and quantitative survey of some indices of documentation for the understanding of overall charges and how individuals New Christians were concerned with the domestic space, using them to maintain criptojudaica religiosity, transformed places housing often esnogas, makeshift synagogue for meetings and celebrations of Judaizing New Christians. The formulations of Michel de Certeau on appropriations and meanings of space - presented by the author in the metaphor of "practice areas" - were integrated into the workforce in order to understand the ways in which the New Christians appropriated the colonial houses, designed these spaces a very specific language in the Crypto, in which women are prominent figures. The works of Jean Delumeau and Bartholomé Benassar integrate the discussion of the Inquisition and the sensibilities of fear in the work performed. The analysis allowed the documentation to understand the meaning and the extent related to the general fear that the Inquisition represented. Some complaints are indicative of fears that can be perceived implicitly based on behaviors and attitudes adopted by the New Christians, others, however, are direct expressions of fear caused by allusion or initiative of the actions of the Inquisition in colonial Brazil in the sixteenth century

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Recognizing the importance the workplace has on mental health of the individual, the objective of this study was to investigate the relationship between the burnout syndrome and the sources of physical and emotional wear which permeate the work conditions of the urban public transport system of the city of Natal. Although existent in international literature, research on burnout in the professional transport category and studies directed to this category are not a tradition in Brazil. The research was carried out using 412 drivers and money-changers of two transport companies of Natal. To collect the data, two questionnaires and a semi-structured interview were used. The first instrument, developed and validated during the research, investigated the sources of wear and the second, the syndrome of burnout. As its main results, two sources of empirical wear were identified as follows: (1) the Conflict of Values and the Lack of Justice at the Workplace, (2) Union and Reward. Besides these, it was observed that there is an incidence of the syndrome of burnout among the drivers and money-changers of urban transport by bus, not only in the caring occupations studied before in Natal and Brazil and that this incidence is related to the sources of wear which permeate the work conditions of these professionals

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Many studies on environmental ecosystems quality related to polycyclic aromatic hydrocarbons (PAH) have been carried out routinely due to their ubiquotus presence worldwide and to their potential toxicity after its biotransformation. PAH may be introduced into the environmet by natural and anthropogenic processes from direct runoff and discharges and indirect atmospheric deposition. Sources of naturally occurring PAHs include natural fires, natural oil seepage and recent biological or diagenetic processes. Anthropogenic sources of PAHs, acute or chronic, are combustion of organic matter (petroleum, coal, wood), waste and releases/spills of petroleum and derivatives (river runoff, sewage outfalls, maritime transport, pipelines). Besides the co-existence of multiples sources of PAH in the environmental samples, these compounds are subject to many processes that lead to geochemical fates (physical-chemical transformation, biodegradation and photo-oxidation), which leads to an alteration of their composition. All these facts make the identification of the hydrocarbons sources, if petrogenic, pyrolytic or natural, a challenge. One of the objectives of this study is to establish tools to identify the origin of hydrocarbons in environmental samples. PAH diagnostic ratios and PAH principal component analysis were tested on a critical area: Guanabara Bay sediments. Guanabara Bay is located in a complex urban area of Rio de Janeiro with a high anthropogenic influence, being an endpoint of chronic pollution from the Greater Rio and it was the scenario of an acute event of oil release in January 2000. It were quantified 38 compounds, parental and alkylated PAH, in 21 sediment samples collected in two surveys: 2000 and 2003. The PAH levels varied from 400 to 58439 ng g-1. Both tested techniques for origin identification of hydrocarbons have shown their applicability, being able to discriminate the PAH sources for the majority of the samples analysed. The bay sediments were separated into two big clusters: sediments with a clear pattern of petrogenic introduction of hydrocarbons (from intertidal area) and sediments with combustion characteristics (from subtidal region). Only a minority of the samples could not display a clear contribution of petrogenic or pyrolytic input. The diagnostic ratios that have exhibited high ability to distinguish combustion- and petroleum-derived PAH inputs for Guanabara Bay sediments were Phenanthrene+Anthracene/(Phenanthrene+Anthracene+C1Phenanthrene); Fluorantene/(Fluorantene+Pyrene); Σ (other 3-6 ring PAHs)/ Σ (5 alkylated PAH series). The PCA results prooved to be a useful tool for PAH source identification in the environment, corroborating the diagnostic indexes. In relation to the temporal evaluation carried out in this study, it was not verified significant changes on the class of predominant source of the samples. This result indicates that the hydrocarbons present in the Guanabara Bay sediments are mainly related to the long-term anthropogenic input and not directly related to acute events such as the oil spill of January 2000. This findings were similar to various international estuarine sites. Finally, this work had a complementary objective of evaluating the level of hydrocarbons exposure of the aquatic organisms of Guanabara Bay. It was a preliminary study in which a quantification of 12 individual biliar metabolites of PAH was performed in four demersal fish representing three different families. The analysed metabolites were 1-hydroxynaphtalene, 2-hidroxinaphtalene, 1hydroxyphenanthrene, 9-hydroxyphenanthrene, 2-hydroxyphenanthrene, 1hydroxypyrene, 3-hidroxibiphenil, 3- hydroxyphenanthrene, 1-hydroxychrysene, 9hydroxyfluorene, 4-hydroxyphenanthrene, 3-hydroxybenz(a)pyrene. The metabolites concentrations were found to be high, ranging from 13 to 177 µg g-1, however they were similar to worldwide regions under high anthropogenic input. Besides the metabolites established by the used protocol, it was possible to verified high concentrations of three other compounds not yet reported in the literature. They were related to pyrolytic PAH contribution to Guanabara Bay aquatic biota: 1-hydroxypyrine and 3-hydroxybenz(a)pyrine isomers

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Located on the western edge of the Brazilian northeast, the Parnaíba Basin is an intra cratonic basin with oil production. This study aims at understanding its genesis and evolution, using aeromagnetic and gravity data. We used the spectral analysis of aeromagnetic data to map the depth to the bottom of the magnetic sources in order to assimilate this depth with the depth of the Curie isotherm, and infer the geothermal gradient. Using the spectral analysis technique, we succeeded in mapping the surface of the depth to the bottom of magnetic sources (SBFM), which marks the depth that occur magnetization. In the Parnaíba Basin the SBFM presented depths around -20,5 and -28,5 , which was consistent with an inversion of the same dataset using the technique of Magnetization Vector Inversion (MVI). Furthermore, SBFM topography correlates well with Moho depth, which was estimated from satellite gravimetric data from the GOCE mission (Gravity Field and Steady-State Ocean Circulation Explorer). Assuming that SBFM coincides with the Curie isotherm of magnetite (ICM), defined as the surface at which magnetite ( ) looses its ferromagnetic properties, it was possible to estimate the geothermal gradient. The geothermal gradient in the basin showed values between 19.2 and 26.5 , allowing to estimate the heat flow for the Parnaíba basin after assuming a conductivity of 2.69 . The resulting heat flow values ranged between 51.6 and 71.3 , which is consistent with values found in other works throughout the South American continent. Lithospheric thickness using an empirical relationship, finding values between -65.8 and -89.2 . We propose that thermal structure of Parnaíba basin is influenced by a deep thermal anomaly. This anomaly has heated the lithosphere beneath the basin and has resulted in relatively thin values for the lithospheric thickness and relatively high surface heat flow values. The origin of the anomaly is not clear, but the correlation between Curie depth and Moho topography, suggests that tectonic extension processes could have played a role.

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Through participant observation, held in the administrative region east of Natal / RN, this research aimed to understand about the daily life of men and women living on the streets in the city. How they relate to the space where they live? In this relationship, which uses and survival strategies triggered by this social segment? These were some of the questions that guided this research, in order to highlight the specificities of this way of life and the possible consequences that such a situation could reverberate. In this sense, there was an effort to keep up with people on the streets, their itineraries and seize their narratives. Along the search path - which took place intermittently between the years 2011-2015 - attended spaces of occupation and traffic of this population group in the street, as well as insert me and got involved in events, forums, seminars, meetings and subject of joints on the streets as a political movement (MNPR / RN). They are considered in this study as people on the street to those who occupy the street as their main space of survival and ordering of daily life: in the streets sleep, feed themselves, meet the physiological and hygienic needs, and is where draw sustenance. The street is taken in this research in its broadest sense, including all possible places relatively protected from the cold, rain and exposure to violence, thus includes both open and public spaces: as squares and parks; but also closed and private places: hostels, abandoned warehouses, prisons, etc. It was observed that in none of these spaces guys on the street are established in a fixed manner, in contrast, they experience the roaming, which in part is due to urban systems - which tends to stigmatize them and delete them places - and the very need to survive, because while living in the street differentiated practices are triggered, and these differ from the dominant mode of sedentary life.

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Through participant observation, held in the administrative region east of Natal / RN, this research aimed to understand about the daily life of men and women living on the streets in the city. How they relate to the space where they live? In this relationship, which uses and survival strategies triggered by this social segment? These were some of the questions that guided this research, in order to highlight the specificities of this way of life and the possible consequences that such a situation could reverberate. In this sense, there was an effort to keep up with people on the streets, their itineraries and seize their narratives. Along the search path - which took place intermittently between the years 2011-2015 - attended spaces of occupation and traffic of this population group in the street, as well as insert me and got involved in events, forums, seminars, meetings and subject of joints on the streets as a political movement (MNPR / RN). They are considered in this study as people on the street to those who occupy the street as their main space of survival and ordering of daily life: in the streets sleep, feed themselves, meet the physiological and hygienic needs, and is where draw sustenance. The street is taken in this research in its broadest sense, including all possible places relatively protected from the cold, rain and exposure to violence, thus includes both open and public spaces: as squares and parks; but also closed and private places: hostels, abandoned warehouses, prisons, etc. It was observed that in none of these spaces guys on the street are established in a fixed manner, in contrast, they experience the roaming, which in part is due to urban systems - which tends to stigmatize them and delete them places - and the very need to survive, because while living in the street differentiated practices are triggered, and these differ from the dominant mode of sedentary life.

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A obra estuda as principais correntes político-ideológicas existentes no Rio Grande do Norte no período de transição entre o final do Império e os primeiros anos da República. Através de uma exaustiva pesquisa em fontes jornalísticas e documentais, o autor introduz o leitor no universo das ideias e práticas políticas que marcaram a tensa implantação do regime republicano no Brasil e especialmente no Rio Grande do Norte.

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The purpose of this thesis is to analyze how João Café Filho constituted a discourse of advocate of the labor movement and workers in different sociability spaces. It is intended to understand, on one hand, how political relations were established between different categories of workers and the ‘middle classes’ and, on the other hand, how places were instituted to house the meeting of these relations. It a ims to understand the insertion of Café Filho in union activities in the urban world. It demonstrates specificities of the political culture in Natal emphasizing the dispute between a city politically ruled by a still reigning rural paternalistic mentality and the rise of a new way to experience the urban conflicts which appeared. Temporally, the work is delimited between 1922 (proclaimed by Café Filho himself as the initial period of his political action) and 1937 (when he broke up with Vargas and went into exile in Argentina). The research was constituted by three main document types: several published newspapers between the decades of 1920 and 1930 in the cities of Natal, Recife, São Paulo, Porto Alegre and Rio de Janeiro; the autobiographical memoirs written by Café Filho himself and memoirs of other people who lived in his time. The main pillars that have supported the work were: the concepts of society and individuals (ELIAS, 1994; 1995), political cultures (BERSTEIN, 1998) and theater of the memory (GOMES, 2004); the sociability spaces category (CERTEAU, 1994; MALATIAN, 2001; RIOX, 1996); the biography notion (DOSSE, 2009; LORIGA, 2011). We demonstrated that Café Filho acted in some sociability spaces as: the Jornal do Norte, the Federação Regional do Trabalho and the Partido Democrático Nacional. In such spaces, Café Filho, gradually, become an important leader of workers and, at the same time, linked to national entities led to the opposition that fight against the power established in the Brazilian First Republic. In Café Filho’s interpretation, workers were individuals who needed to fight against the political structures prevailing at that time because the poor living conditions and the low representativeness of this group were caused by the way the political system in the First Republic was structured. After the 1930 Movement, the 3 de Outubro Club, the Jornal and the Labor Federation of Natal were constituted in spaces where the cafeista critical discourse about the government was changed: workers should follow the official syndicalism and defend the 1930 Movement which put Vargas in the presidency of the Republic.

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O contexto hodierno caracteriza-se como um panorama de uso contínuo de informação nas mais variadas esferas da sociedade. A informação é usada em diversos contextos sob vários formatos e isso se torna possível com a evolução tecnológica realizada em ritmo acelerado, sobretudo nos últimos dois séculos. Essa evolução trouxe consigo a possibilidade ampliada de acesso à informação, mas por outro lado, impôs desafios circunstanciais no seu tratamento e difusão. Nos diversos tipos de unidades de informação, faz-se necessária a adoção de estratégias para a melhoria do gerenciamento e desenvolvimento das coleções, sobretudo as coleções digitais. De tal modo, o trabalho visa a traçar um panorama ligado às questões relacionadas à comunicação cientifica com a bibliotecas universitárias, com vistas a ampliar o debate sobre o desenvolvimento digital de coleções de periódicos em bibliotecas universitárias, bem como aspectos relacionados à adoção de critérios de seleção e avaliação destes itens de informação. Aborda os casos específicos, como o do Portal Capes e o SciELO como coleções digitais de periódicos sujeitos a estratégias de desenvolvimento das coleções. Aponta opções para a melhoria da gestão da coleção digital em bibliotecas universitárias. A metodologia empregada foi a de pesquisa bibliográfica em uso de fontes eletrônicas e convencionais, bem como análise de critérios utilizados na Avaliação e Coleções para Bibliotecas Universitárias e o Indicadores Qualis pela Condenação de Aperfeiçoamento de Pessoa de Ensino Superior (CAPES).

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Leishmaniasis are endemic diseases wild spread in the New and Old World, caused by the flagelated protozoan Leishmania. In the New World, the distribution of different forms of leishmaniasis is mostly in tropical regions. In the State of Rio Grande do Norte, Northeast Brazil, 85% of the captured sand flies fauna is Lutzomyia longipalpis. The distribution of the sand fly vector in the state overlaps with the disease distribution, where the presence of sand flies is associated with presence of animals shelters. The aim of this study was to analyse the blood meal preference of sand flies vector from the genus Lutzomyia spp. in laboratory conditions, to verify the vector life cicle at different temperatures sets and to identify the main blood meal source in endemic areas for visceral leishmaniasis (VL) at peri-urban regions of Natal. Sand flies samples were collected from the municipalities of São Gonçalo do Amarante and Nísia Floresta where female sand flies were grouped for the colony maintenance in the laboratory and for the analysis of the preferred source of sand fly blood meal in natural environment. The prevalence of blood meal preference and oviposition for the females sand flies was 97% for Cavia porcellus with oviposition of 19 eggs/female; 97% for Eqqus caballus with 19 eggs/female; 98% for human blood with 14 eggs/female; 71.3% for Didelphis albiventris with 8.4 eggs/female; 73% for Gallus gallus with 14 eggs/female; 86% for Canis familiaris with 10.3 eggs/female; 81.4% for Galea spixii with 26 eggs/female; 36% for Callithrix jachus with 15 eggs/female; 42.8% for Monodelphis domestica with 0% of oviposition. Female sand flies did not take a blood meal from Felis catus. Sand flies life cycle ranged from 32-40 days, with 21-50 oviposition rates approximately. This study also showed that at 32°C the life cycle had 31 days, at 28° C it had 50 days and at 22°C it increased to 79 days. Adjusting the temperature to 35°C the eggs did not hatch, thus blocking the life cycle. A total of 1540 sand flies were captured, among them, 1.310 were male and 230 were female. Whereas 86% of the sand flies captured were Lu. longipalpis as compared to 10.5% for Lu. evandroi and, 3.2% for L. lenti and 0.3% for Lu whitmani. The ratio between female and male sandfly was approximately 6 males to 1 female. In Nísia Floresta, 50.7% of the collected females took their blood meal from armadillo, 12.8% from human. Among the female sand flies captured in São Gonçalo do Amarante, 80 of them were tested for the Leishmania KDNA infectivity where 5% of them were infected with Leishmania chagasi. Female Lutzomyia spp. showed to have an opportunistic blood meal characteristic. The behavioral parameters seem to have a higher influence in the oviposition when compared to the level of total proteins detected in the host s bloodstream. A higher Lu. longipalpis life cycle viability was observed at 28°C. The increase of temperature dropped the life cycle time, which means that the life cycle is modified by temperature range, source of blood meal and humidity. Lu longipalpis was the most specie found in the inner and peridomiciliar environment. In Nísia Floresta, armadillos were the main source of blood meal for Lutzomyia spp. At São Gonçalo do Amarante, humans were the main source of blood meal due to CDC nets placed inside their houses

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The plants are often exposed to variations in environmental conditions that may trigger metabolic disturbances leading to a consequent loss in productivity of crops. These stressful conditions usually induce an accumulation of reactive oxygen species (ROS) in the cell, a condition known how oxidative stress. Among these species, hydrogen peroxide (H2O2) is an important molecule involved in numerous signaling mechanisms. The present study aimed to understand the relationship between the different enzymatic mechanisms of elimination of H2O2 by catalase (CAT) and ascorbate peroxidase (APX) in leaf tissues of seedlings of the species Vigna unguiculata L. Walp, under conditions of oxidative stress induced by application of CAT inhibitor, 3-amino-1,2,4-triazole (3-AT), and H2O2 itself on the roots. Three experiments were conducted. The first experiment was performed applying the compound 3-AT (5 mM) during the time (hours). In the second experiment, seedlings were exposed to different concentrations of H2O2 (2.5, 5.0, 7.5, 10 mM) for 48 h. The third strategy included the pre-treatment with H2O2 (2.5 mM) for 24 h, followed by subsequent treatment with the inhibitor 3-AT and recovery control condition. Treatment with 3-AT causes a strong inhibition of CAT activity in leaf tissues accompanied by an increase of activity of APX. However a decrease in oxidative damage to lipids is not observed as indicated by TBARS. It was observed that activity of APX is directly linked to the content of peroxide. Inductions in the activities of CAT and APX were observed mainly in the seedlings treated with 2.5 mM H2O2. This can be associated with a decrease in oxidative damage to lipids. In contrast, one same tendency was not observed in treatments with higher concentrations of this ROS. These results suggest that the concentration of 2.5 mM H2O2 can induce responses antioxidants later in seedling cowpea. This concentration when applied as pre-treatment for 24 h promoted an induction systems removers CAT and APX, both in activity and in terms of gene expression. However this increment was not observed in the recovered plants and the plants subsequently subjected to 3-AT. Additionally, the pretreatment was not sufficient to attenuate the inhibition of CAT activity and oxidative damage to lipids caused by the subsequent application of this inhibitor. The results showed that the application of 3-AT and H2O2 in the root systems of seedlings of cowpea promote changes in the parameters analyzed in leaf tissues that indicate a direct response to the presence of these factors or systemic signaling mecanisms. H2O2 appears to activate the responses of two antioxidant systems in this study thar does not promote greater protection in case of additional treatment with 3-AT. This demonstrates the importance of the CAT system. In this work, complete results indicate that there is a difference between the signaling and the effects caused by exposure to H2O2 and by treatment with 3-AT

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The mobilization of food reserves in storage tissues and allocation of their hydrolysis products in the growing axis are critical processes for the establishment of seedlings after germination. Therefore, it is crucial for mobilization of reserves to be synchronized with the growing axis, so that photosynthetic activity can be started before depletion of reserves. For this, integrative approaches involving different reserves, different hydrolysis products and interaction between storage and growing axis tissues, either through hormones or metabolites with signaling role, can contribute greatly to the elucidation of the regulation mechanisms for reserve mobilization. In this study, was hypothesized that hormones and metabolites have different actions on reserve mobilization, and there must be a crossed effect of sugars on the mobilization of proteins and amino acids on lipids and starch mobilization in sunflower seedlings. This study was conducted with seeds of sunflower (Helianthus annuus L.) hybrid Helio 253 using in vitro culture system. Seeds were germinated on Germitest® paper and grown on agar-water 4 g/L without addition of nutrients during 9 days after imbibition (DAI) for growth curve. To verify the effect of metabolites and hormones, seedlings were transferred in the 2nd DAI to agar-water 4 g/L supplemented with increasing concentrations of sucrose or L-glutamine, abscisic acid, gibberellic acid or indolebutyric acid. The results of this study confirm that the mobilization of lipids and storage proteins occurs in a coordinated manner during post-germination growth in sunflower, corroborating the hypothesis that the application of external carbon (sucrose) and nitrogen (L-glutamine) sources can delay the mobilization of these reserves in a crossed way. Moreover, considering the changes in the patterns of reserve mobilization and partition of their products in seedlings treated with different growth regulators, it is evident that the effects of metabolites and hormones must involve, at least in part, distinct mechanisms of action

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The mesoporous molecular sieves of MCM-41 and AlMCM-41 type are considered as promising support for metal in the refining processes of petroleum-based materials as catalysts and adsorbents for environmental protection. In this work the molecular sieves MCM-41 and AlMCM-41 were synthesized by replacing the source of silica conventionally used, for quartz, an alternative and abundant, and the use of waste from the production of diatomaceous earth, an aluminum-silicate, as a source aluminum, due to abundant reserves of diatomaceous earth in the state of Rio Grande do Norte in the city of Ceará-Mirim, with the objective of producing high-value materials that have similar characteristics to traditional commercial catalysts in the market. These materials were synthesized by the method of hydrothermal synthesis at 100 º C for 7 days and subjected to calcination at 500 º C for 2 hours under flow of nitrogen and air. The molecular sieves were characterized by X-ray diffraction (XRD), differential thermal analysis (DTA) and thermogravimetric analysis (TG), adsorption of N2 (BET and BJH methods), spectroscopy in the infra red (FTIR), microscopy scanning electron (SEM) and transmission electron microscopy (TEM). The analysis indicated that the synthesized materials showed characteristic hexagonal structure of mesopores materials with high specific surface area and sort and narrow distribution of size of pores

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The production of synthesis gas has received renewed attention due to demand for renewable energies to reduce the emissions of gases responsible for enhanced greenhouse effect. This work was carried out in order to synthesize, characterize and evaluate the implementation of nickel catalysts on MCM-41 in dry reforming reactions of methane. The mesoporous molecular sieves were synthesized using as silica sources the tetraethyl orthosilicate (TEOS) and residual glass powder (PV). The sieves were impregnated with 10% nickel to obtain the metallic catalysts (Ni/MCM-41). These materials were calcined and characterized by Thermogravimetric Analysis (TG), Infrared spectroscopy (FTIR), X-ray Diffraction (XRD), Temperature-Programmed Reduction (TPR) and N2 Adsorption/Desorption isotherms (BET/BJH). The catalytic properties of the samples were evaluated in methane dry reforming with CO2 in order to produce synthesis gas to be used in the petrochemical industry. The materials characterized showed hexagonal structure characteristic of mesoporous material MCM-41 type, being maintained after impregnation with nickel. The samples presented variations in the specific surface area, average volume and diameter of pores based on the type of interaction between the nickel and the mesoporous support. The result of the the catalytic tests showed conversions about 91% CO2, 86% CH4, yelds about 85% CO and 81% H2 to Ni/MCM-41_TEOS_C, and conversions about 87% CO2, 82% CH4, yelds about 70% CO and 59% H2 to Ni/MCM-41_PV_C. The similar performance confirms that the TEOS can be replaced by a less noble materials