Diversidade de paronellidae (collembola, arthropleona, entomobryoidea) no nordeste brasileiro, com ênfase em áreas úmidas da caatinga

Paronellidae is among the most diverse and distinctive components of epiedaphic Collembola in tropical countries. However, only 15 species of the family were recorded in Brazil, and only two of them were record in northeast region of the country. This condiction is clearly related to low sampling efforts and lack of specialists working with the group. Due to this reality, this work aimed to study the Paronellidae fauna, under a taxonomic point of view, in six distinct environments in Northeastern Brazil (from Alagoas, Bahia, Ceará, Piauí and Paraíba states), five areas of Caatinga and one from Atlantic Rain Forest biome. Collections were made during the rainy season on each area. The specimens were analyzed under stereomicroscope and mounted in glass slides for microscopy. The specimens identified as Paronellidae had their occurrence recorded and five new species were described. An identification key to the brazilian genera of the family was also prepared. Twelve species of Paronellidae were recorded for the first time to Brazil: Campylothorax mitrai; Lepidonella. sp. nov. 1; Lepidonella sp. nov. 2, Lepidonella sp. nov. 3, Lepidonella sp. nov 4, Lepidonella sp. nov. 5; Dicranocentruga sp. Nov. 1; Dicranocentruga sp. Nov. 2; Dicranocentruga sp. Nov. 3; Paronella sp. nov.1; Serroderus sp. nov.1 and Trogolaphysa. sp. 1, where C. mitrai, Lepidonella. sp. nov 1, Dicranocentruga sp. nov 1, Dicranocentruga sp. nov 2 and Dicranocentruga sp. nov 3 were described. Serroderus and Dicranocentruga genera were recorded for the first time to Brazil. The description of Lepidonella sp. nov 1 also represents the first description of a species of the genus for the country. The data presented show a high potential species richness to Paronellidae, not only in the northeast region, but as in Brazil. In fact, with the records presented in this work, the number of recorded species of Paronellidae in the country increased by 80%. The study of this particular fauna may direct environmental conservation policies, especially in areas of Caatinga

O impacto dos custos não-gerenciáveis na determinação das tarifas de energia elétrica: um estudo nas companhias distribuidoras do nordeste que tiveram revisão tarifária nos exercícios de 2003 e 2004

This work presents results derived from a study related to impact on non-controllable costs in the determination of energy taxes. This is done analyzing tax review practiced by concessionaries responsible for the distribution of electrical energy located in the Northeastern Region of Brazil, between 2003 and 2004. This Region was chosen as a study area due to the researcher s expectation in congregating companies that deliver services to markets that have similar social-economical profiles. A brief explanation related to the restructuring of the electrical sector in Brazil is presented, pointing out that there was privatization of the great majority of these companies. The study also points out the definition of regulating rules in service delivery process. The components of taxes that are practiced by these companies aimed at final consumers, as well as the market as a whole and the revision process that is executed by Agência Nacional de Energia Elétrica ANEEL for the definition of these taxes are demonstrated in the research. A brief historical of the concessionaires that were focus of the research is presented, totaling five companies. Some data used by ANEEL in the tax review process was analyzed as well as data on components of approved taxes. It is concluded that as a media 47, 49% of the components of taxes in the researched companies correspond to the non-controllable costs. These is done considering previous classification by ANEEL in the tax review process. Although, if it is considered that these companies since 2006, by the means of participation in energy auctions are able to negotiate energy prices for their own needs, it is concluded that these concession contracts guarantee the delivery of the service to the costumer in the total tribute. The percentage of non-controllable costs is 16, 27% average of the tax. This means, amongst other information, that the government has a great deal of responsibility in the formation of price practiced by these companies and its target markets

Caracterização e composição florística de uma comunidade savânica no Rio Grande do Norte, Brasil : subsídios para a conservação

Studies on Brazilian biodiversity are still very few and can observe the difference of knowledge between the different regions of the country. This affirmation can be verified in the investigation to identify the rare species in Brazil and the key biodiversity areas (ACBs). In that study were identified for Brasil 2.256 rare species and 752 ACBs. The Rio Grande do Norte (RN) was the only Brazilian state that has not been identified any rare species and no ACBs, possibly due to the lack of floristic studies in this state. A particular area was selected for this study: an area of ecological tension with savanna physiognomy in Rio do Fogo, RN. This savanna community is represented in RN in a fragment and immersed in restinga and caatinga and was identified and described only through of radar imagens there are no studies to date in loco . We have prepared the following questions about this community savanna: 1) The region delimited and described by through of radar images by the RADAMBRASIL, 1976, can be associated of the Cerrado, in terms of floristic ?; 2) What is the floristic composition of this area? This area includes rare species, endemic or endangered? 3) What is the geographical and phytogeographical distribution of plant species registered in this area? 4) Those plant species registered are endemic or have affinity with other areas phytoecological Brazilian? To answer these questions we performed a floristic inventory of the August 2007 to September/2009. The results are presented in two chapters (manuscripts). The first chapter, titled "The Savannah Rio Grande do Norte: floristic links with other plant formations in the Northeast and Center-West Brazil" was submitted to the Revista Brasileira de Botância. Chapter 1 discusses the phytogeographical distribution of the species, by comparing floristic studies conducted in the Cerrado, Caatinga and Restinga in the Northeast and Cerrado of the Central Brazil. The analysis of data of this study and compilation with other studies indicated that: i) the record of 94 plant species; ii) of total species, about 64% are associated with the Cerrado, the second specialized bibliography, and about 78% as the List of Species of Flora of Brazil. However, about 73% of total species (94) are also distributed in the Caatinga, the Atlantic forest 64%, the Amazon forest 64%, the Pantanal 15% and the Pampa 12%. Floristically the data show that the community studied is influenced by other floras, has a structure where grasses dominate and also because of his appearance the same savanna then be classified as a Savana gramíneo-lenhosa do tabuleiro . Chapter 2, titled "Considerations on the flora of a savanna community in Rio Grande do Norte, northeastern Brazil: Subsidy key area for conservation" was submitted to the Revista Natureza e Conservação. This has the objective of improve the knowledge of flora of Rio Grande do Norte and to identify possible rare species and consequently increase the key areas of biodiversity in Brazil. The data indicated that: i) of 94 species registered in the study area, 40 were new records for the Rio Grande do Norte state; ii) These citations to unpublished state, Stylosanthes montevidensis Vogel (Fabaceae) and Aristida laevis (Nees) Kunth (Poaceae) are indicated for the first time to the Northeast of Brazil; iii) are registered in the area 24 species endemic to Brazil and 63 non-endemic; iv) Aspilia procumbens Baker (Asteraceae) registered in the area is considered a restricted species and micro endemic Rio Grande do Norte, ie rare species; v) Aspilia procumbens is also cited in the category of critically endangered species and Stilpnopappus cearensis Hubber (Asteraceae) a species vulnerable to extinction. This study shows a new area phytoecological in Rio Grande do Norte and indicates the area's potential to contribute with the sites of global significance for biodiversity conservation, either locally, regionally and nationally. This will certainly contribute to respond some targets set by the Global Strategy for Plant Conservation and the Convention on Biological Diversity such as the inventory of vegetal diversity in a region with little collection, which will provide data that contributes to questions and themes related to biodiversity.

Triagem antifúngica de extratos obtidos de espécies vegetais do nordeste brasileiro

The increase in the incidence of fungal infections due to the drug-resistance or to the number of patients with immune alterations such as AIDS, chemotherapy or organ transplantation, has done the research necesseray for new antifungal drugs. The species from Northeastern Brazil may become an important source of innovative natural molecules. To evaluate the antifungal activity of 10 medicinal plants from Northeastern Brazil, traditionally used as antimicrobial agents, 30 crude extracts (CE) were tested in vitro against four standard species of Candida spp. The CE most promising of these plants were evaluated against yeasts of the oral cavity of kidney transplant patients and through a bioassay-guided fractionation. The extracts form leaves of E. uniflora, the stem bark of L. ferrea and leaves of P. guajava showed significant activity against all yeasts evaluated, with MIC values between 15.62 and 62.5 μg/mL. E. uniflora also showed fungicidal properties against all yeasts, especially against Candida dubliniensis. In patients with immune systems compromised, such as transplanted, oral candidiasis manifests mainly due to immunosuppressive therapy, and resistance to conventional antifungals. The CE of E. uniflora presented range of MIC values between 1.95 to 1000 μg/mL, and lower MIC50 and MIC90 values were observed against C. non-albicans. Due the better results, the CE of E. uniflora was elected to performe the bioassay-guided fractionation. Thus it was possible to obtain enriched fractions, which showed good inhibitory ability against ATCC strains of Candida spp. It was also possible to perform experiments to verify the production of biofilm in two strains of C. dubliniensis and action of extracts and fractions on the same. With this, we observed a behavior between the yeast ATCC and clinical isolate. In addition, CE, fractions and subfractions of E. uniflora inhibit planktonic cells to preventing the growth of biofilm. The preliminary chemical characterization of the fractions obtained revealed the presence of polyphenols (especially flavonoids and tannins). Finally, the results suggests that among the plant species studied, E. uniflora showed a pattern very promising as regards the antifungal, requiring further study of purification and structural elucidation of compounds in order to verify that the antifungal effect found can be attributed to a specific compound or some mechanism depends on synergistic the mixture of polyphenols

O papel da tecnologia cênica e seus desdobramentos para uma economia da produção cultural no nordeste

O papel da tecnologia na produção contemporânea em artes cênicas vem influenciando profundamente as formas de recepção e produção de Teatro, Dança, espetáculos de Circo, shows musicais, entre outras manifestações espetaculares organizadas. Sua aplicação se estende amplamente a outras áreas que necessitam enfatizar o caráter cênico de seus processos de fruição como é o caso dos museus, feiras de ciências, exibições e mostras em artes visuais e o aparato tecnológico de luz, som e configuração espacial usados para estes fins. Neste sentido, o desenvolvimento deste tipo de tecnologia vem gerando e alimentando cadeias produtivas que movimentam uma economia da produção cultural e criam uma rede de relações articuladas em diferentes níveis de atuação, envolvendo produtores de equipamento, fornecedores, lighting designers, cenógrafos, profissionais de sonorização, arquitetos, técnicos de montagem e operação, instituições ensino especializadas, associações de área, entre outros. O foco deste trabalho se concentra em demonstrar como a análise de demandas de tecnologia cênica articuladas pelos sistemas de produção cultural, em particular na região Nordeste do Brasil, possibilitam compreender modelos de organização em curso, contribuindo para o desenvolvimento de uma reflexão multidisciplinar acerca dos processos de produção artística de natureza cênica e como esta produção é afetada pelos limites e possibilidades dos aspectos que caracterizam uma economia destas produções

Anisotropia sísmica crustal na região de Cascavel - CE

This dissertation presents a study on crustal seismic anisotropy in Cascavel - CE. The earthquake data employed here are from the Seismological Laboratory at Universidade Federal do Rio Grande do Norte (UFRN) and were colected from 29 September 1997 to 05 march 1998 using six three-component digital seismographic stations. In general, the cause of the observed seismic anisotropy in many regions of the world is interpreted in terms of fluid-filled stress aligned microcracks in the rockmass (EDA). In other words, the polarisation direction of the faster shear-wave splitting is parallel to SHmax. However, other researches on seismic anisotropy carried out in NE Brazil have shown a remarkable consistency of the faster shear-wave polarisation direction with the direction of the Precambrian fabric. The present work is another case study that is used to investigate this issue. In order to map the Precambrian fabric we used aeromagnetic data, since the study area is mostly covered with sediments (up to 50m thick) and in-situ field mapping would be very difficult to be carried out. According to the results from the present research, the observations of the faster shear-wave polarisation directions in two seismographic stations in Cascavel region are best explained in the framework of EDA. For the remaining two stations, the observed anisotropy may have two interpretions: (i) - 90_ flips of the direction of polarisation of the faster shear-wave, since that the event-to-station ray path would be through the fracture zone and hence would travel under a higher pore pressure and (ii) - the observed seismic anisotropy would agree with the direction on the ductile Precambrian fabric

Tendências e projeções da mortalidade pelos cânceres específicos ao gênero no Brasil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES

Foraminíferos, ostracodes e microfauna associada da plataforma continental equatorial norte-rio-grandense, NE Brasil: área Porto do Mangue a Galinhos

This study was conducted in the adjacent Brazilian equatorial inner shelf to Rio Grande do Norte, between the region of Porto do Mangue and Galinhos. The main objective is the characterization of biogenic sediments, especially foraminifera and ostracod collected on the surface of the seafloor. The methodology involved standard procedures including literature, surveys, processing of samples in the laboratory and identification of foraminifera and ostracods by genera or species under stereo microscopy and scanning electron microscopy (SEM). Multivariate statistical analyzes and study of ecological indexes were also applied to the study of foraminifera. Three transects, from inner shelf to slope were sampled: profile 01 (east, near Galos), profile 02 (center, near the city of Macau) and profile 03 (west, near Ponta do Mel). Results indicated the predominance of benthic foraminifera and little plankton occurrence. Benthic foraminifera genera observed in abundance were Quinqueloculina, Textularia, Globigerina and Pyrgo, Quinqueloculina, Textularia, Pyrgo, Ammonia, Elphidium, Pseudononion, Peneroplis, Bolivina and Poroeponides, occurred more frequently. Less frequently been described Amphistegina, Archaias, Bigenerina, Cibicides, Cassidulina, Amphicorina, Cornuspira, Paterina, Hopkunsina, Oolina, Uvigerina, Fusenkoina, Nonionella, Amphisorus, Wiesrella, Reussella, Reophax, Nodosaria, Marginulina and Cyclogyra. Six genera of ostracods were also identified: Puriana variabilis / P. convoluted?, Loxoconcha sp, Bairdiidae, Xestoleberis sp, Hemicytheridae and Ruggiericythere sp. Groups of organisms found in the studied shelf presented chemical composition of Ca, C, O, Na, Cl, Al, Mg, and Si. The proportions of chemical elements may vary according to the type of biogenic sediment, with the highest values identified as Ca, C, Cl, Na and O. The absolute dating by carbon 14 method indicated sediments of different colors (light and dark), correspond to a single age from 3000 to 6000 years BP, related to the Quaternary. These data intend to complement information about biogenic sediments in the Brazilian continental shelf, especially in the Northeast, where there is a lack of such studies.

Foraminíferos, ostracodes e microfauna associada da plataforma continental equatorial norte-rio-grandense, NE Brasil: área Porto do Mangue a Galinhos

This study was conducted in the adjacent Brazilian equatorial inner shelf to Rio Grande do Norte, between the region of Porto do Mangue and Galinhos. The main objective is the characterization of biogenic sediments, especially foraminifera and ostracod collected on the surface of the seafloor. The methodology involved standard procedures including literature, surveys, processing of samples in the laboratory and identification of foraminifera and ostracods by genera or species under stereo microscopy and scanning electron microscopy (SEM). Multivariate statistical analyzes and study of ecological indexes were also applied to the study of foraminifera. Three transects, from inner shelf to slope were sampled: profile 01 (east, near Galos), profile 02 (center, near the city of Macau) and profile 03 (west, near Ponta do Mel). Results indicated the predominance of benthic foraminifera and little plankton occurrence. Benthic foraminifera genera observed in abundance were Quinqueloculina, Textularia, Globigerina and Pyrgo, Quinqueloculina, Textularia, Pyrgo, Ammonia, Elphidium, Pseudononion, Peneroplis, Bolivina and Poroeponides, occurred more frequently. Less frequently been described Amphistegina, Archaias, Bigenerina, Cibicides, Cassidulina, Amphicorina, Cornuspira, Paterina, Hopkunsina, Oolina, Uvigerina, Fusenkoina, Nonionella, Amphisorus, Wiesrella, Reussella, Reophax, Nodosaria, Marginulina and Cyclogyra. Six genera of ostracods were also identified: Puriana variabilis / P. convoluted?, Loxoconcha sp, Bairdiidae, Xestoleberis sp, Hemicytheridae and Ruggiericythere sp. Groups of organisms found in the studied shelf presented chemical composition of Ca, C, O, Na, Cl, Al, Mg, and Si. The proportions of chemical elements may vary according to the type of biogenic sediment, with the highest values identified as Ca, C, Cl, Na and O. The absolute dating by carbon 14 method indicated sediments of different colors (light and dark), correspond to a single age from 3000 to 6000 years BP, related to the Quaternary. These data intend to complement information about biogenic sediments in the Brazilian continental shelf, especially in the Northeast, where there is a lack of such studies.

Contra as Secas: a engenharia e as origens de um planejamento regional no nordeste brasileiro

Droughts surfaced in 1877 as a crucial problem for the birthing Brazilian nation. Engineers, who formed the country's technical and scientific elite, took it upon themselves to study, understand and fight the problem through planned actions of intervention on space. This work, based on proposals and discussions contained in engineering magazines and reports, aims to provide elements for the comprehension of how these systematized actions against droughts, in the Iate nineteenth and early twentieth century, contributed to spatial analysis and the formation of a (then-inexistent) regional and territorial planning discipline in Brazi!. Engineers, by taking up the position of masterminds in the country's modernization, guaranteed for themselves personal economic stability, social prestige and political power. By understanding nature, either as a resource to be exploited or an adversary to national progress, they contributed to the delimitation of the region now known as the Northeast. By seeking to understand the drought phenomenon, they created knowledge about the space they sought to intervene on; by constructing their projects amid political and economical difficulty, they changed the organizational structures of cities and country in the northeast. The proposals for açudes (Iarge water reservoirs) allowed the fixation of population and the resistance against droughts; the roads - railroads and automotive roadways - connected the sertão to the capitais and the coast, speeding up help to the affected populations during droughts and allowing the circulation of goods so as to strengthen the local economies in normal rimes. The adopted practices and techniques, adapted from foreign experience and developed through trial and improvement, were consolidated as an eminently spatial intervention course, even if a theoretical body of regional or territorial planning wasn't formed in Brazil. Regional Planning proper was first applied in the country in the Northeast itself, in the 1950s, based off an economical view of reality in order to achieve development. The engineer's work prior tothat date, however, cannot be dlsconsldered. It was proved that, despite facing financial and political hurdles, engineers had a profound commitment to the problem and intended to act systematically to transform the economical and social relations in the region, in order to be victorious in their struggle against droughts

O Litoral e a metrópole dinâmica imobiliária, turismo e expansão urbana na região metropolitana de Natal-RN

The metropolitan regions of Northeast Brazil are being gradually included in a scenario of international investments, which are motivated by the restructuring of both touristic and real-estate sectors. The new capital, real-estate developers and space configurations that result from this process indicate the need for the creation and implementation of public tools which should, at least, allow the mitigation of the urban impacts and environmental losses resulting from this situation. The effects on landscape and on the socio-spatial configuration result from the intensification caused by the dynamism of the "real estate-tourism" sector. There is a regional integration as an expression of the urban expansion of the metropolitan area of Natal. This study investigates the uniqueness of the restructuring and territorial integration of coastal areas and the strategies of the circuit of capital accumulation formed by linking the real estate to tourism. It is intended to increase the understanding about the strategies of tourism, real estate and public policy agents involved in this territorial reconfiguration and in the fund-raising needed for the investments, to understand the existing social and environmental effects and their future trends and also to understand the forms of spatial production as results from the practices of approaching the land transformation and the tourism valorization of the landscape, in a synchronous manner, first in the Northeast region and, as a focal study, in the Metropolitan Area of Natal. Likewise, it is intended to apprehend the current processes of metropolization of the eastern coast of Rio Grande do Norte, in addition to indicate its physical-territorial transformation and the types of projects/developments promoted by the market in the recent period. Based upon analysis undertaken for the Metropolitan Region of Natal RN, this piece of work presents some considerations on possible legal instruments that can be adjusted to the municipalities which are experiencing the impact of this peculiar and recent phenomenon in the region, caused by the arrival of the real estate-touristic capital. It is also intended to point out basic proposals to the forms of public intervention, in a speculative way, starting from a Metropolitan Planning project within a medium and long term

Análise do transcriptoma das glândulas venenosas do escorpião Tityus stigmurus

In Brazil, accidents with scorpions are considered of medical importance, not only by the high incidence, but also for the potentiality of the venom from some species in determining severe clinical conditions. Tityus stigmurus is a widely distributed scorpion species in Northeastern Brazil and known to cause severe human envenomations, inducing pain, hyposthesia, edema, erythema, paresthesia, headaches and vomiting. The present study uses a transcriptomic approach to characterize the molecular repertoire from the non-stimulated venom gland of Tityus stigmurus scorpion. A cDNA library was constructed and 540 clones were sequenced and grouped into 37 clusters, with more than one EST (expressed sequence tag) and 116 singlets. Forty-one percent of ESTs belong to recognized toxin-coding sequences, with antimicrobial toxins (AMP-like) the most abundant transcripts, followed by alfa KTx- like, beta KTx-like, beta NaTx-like and alfa NaTx-like. Our analysis indicated that 34% include other possible venom molecules , whose transcripts correspond to anionic peptides, hypothetical secreted peptides, metalloproteinases, cystein-rich peptides and lectins. Fifteen percent of ESTs are similar to cellular transcripts. Sequences without good matches corresponded to 11%. This investigation provides the first global view of cDNAs from Tityus stigmurus. This approach enables characterization of a large number of venom gland component molecules, which belong either to known or atypical types of venom peptides and proteins from the Buthidae family

Estudo do genoma do vírus causador da mionecrose infecciosa em camarões e desenvolvimento de métodos para detecção de diferentes variantes

Shrimp farming is one of the activities that contribute most to the growth of global aquaculture. However, this business has undergone significant economic losses due to the onset of viral diseases such as Infectious Myonecrosis (IMN). The IMN is already widespread throughout Northeastern Brazil and affects other countries such as Indonesia, Thailand and China. The main symptom of disease is myonecrosis, which consists of necrosis of striated muscles of the abdomen and cephalothorax of shrimp. The IMN is caused by infectious myonecrosis virus (IMNV), a non-enveloped virus which has protrusions along its capsid. The viral genome consists of a single molecule of double-stranded RNA and has two Open Reading Frames (ORFs). The ORF1 encodes the major capsid protein (MCP) and a potential RNA binding protein (RBP). ORF2 encodes a probable RNA-dependent RNA polymerase (RdRp) and classifies IMNV in Totiviridae family. Thus, the objective of this research was study the IMNV complete genome and encoded proteins in order to develop a system differentiate virus isolates based on polymorphisms presence. The phylogenetic relationship among some totivirus was investigated and showed a new group to IMNV within Totiviridae family. Two new genomes were sequenced, analyzed and compared to two other genomes already deposited in GenBank. The new genomes were more similar to each other than those already described. Conserved and variable regions of the genome were identified through similarity graphs and alignments using the four IMNV sequences. This analyze allowed mapping of polymorphic sites and revealed that the most variable region of the genome is in the first half of ORF1, which coincides with the regions that possibly encode the viral protrusion, while the most stable regions of the genome were found in conserved domains of proteins that interact with RNA. Moreover, secondary structures were predicted for all proteins using various softwares and protein structural models were calculated using threading and ab initio modeling approaches. From these analyses was possible to observe that the IMNV proteins have motifs and shapes similar to proteins of other totiviruses and new possible protein functions have been proposed. The genome and proteins study was essential for development of a PCR-based detection system able to discriminate the four IMNV isolates based on the presence of polymorphic sites

Adição de vermiculita expandida mícron em pastas de baixa densidade para cimentação de poços de petróleo

The northeastern region of Brazil has a large number of wells producing oil using a method of secondary recovery steam injection, since the oil produced in this region is essentially viscous. This recovery method puts the cement / coating on thermal cycling, due to the difference in coefficient of thermal expansion between cement and metal coating causes the appearance of cracks at this interface, allowing the passage of the annular fluid, which is associated with serious risk socioeconomic and environmental. In view of these cracks, a correction operation is required, resulting in more costs and temporary halt of production of the well. Alternatively, the oil industry has developed technology for adding new materials in cement pastes, oil well, providing high ductility and low density in order to withstand the thermo-mechanical loads generated by the injection of water vapor. In this context, vermiculite, a clay mineral found in abundance in Brazil has been applied in its expanded form in the construction industry for the manufacture of lightweight concrete with excellent insulation and noise due to its high melting point and the presence of air in their layers lamellar. Therefore, the vermiculite is used for the purpose of providing low-density cement paste and withstand high temperatures caused by steam injection. Thus, the present study compared the default folder containing cement and water with the folders with 6%, 8% and 10% vermiculite micron conducting tests of free water, rheology and compressive strength where it obtained the concentration of 8 % with the best results. Subsequently, the selected concentration, was compared with the results recommended by the API standard tests of filtered and stability. And finally, analyzed the results from tests of specific gravity and time of thickening. Before the study we were able to make a folder with a low density that can be used in cementing oil well in order to withstand the thermo-mechanical loads generated by steam injection

Síntese de zeólita A a partir de diatomita como fonte de aluminossilicato

The synthesis of zeolites from natural sources of silicon and aluminum are promising alternative routes to obtain porous or zeolite MCM family. Such materials are typically used in catalytic processes and / or adsorption is to obtain new products or for separation and purification processes thereof. Environmental legislation is becoming stricter and requires the use of materials more efficient, aiming to achieve pollution prevention, by gas or liquid contaminants in the environment. In order to obtain a material with environmentally friendly features, this study aimed at the synthesis of zeolite A, from an amorphous sediment, diatomite, which is found in abundance in the northeast region of Brazil, may be substituted for conventional products the production of zeolite, involving higher costs. The methodology for obtaining the "Zeolite A" using as a source of silica and alumina diatomite is simple, since this is a source of silicon, not requiring therefore a structural driver, but also by heat treatment, only drying conventional to remove water. The "zeolite A" was obtained from diatomite, but as an intermediate step we obtained the sodalite. The characterization was made by the following techniques: EDX, XRD, FT-IR, SEM and determining a specific area by the BET method and the BJH method for checking the diameter of pores. By characterization of the obtained material was first demonstrated the achievement of sodalite and after modification of the same, there was obtained zeolite A