Reconhecimento da tectônica mezozóica-cenozóica na borda leste da Bacia do Paraná através da aplicação de traços de fissão em apatitas no Domo de Pitanga (Sudoeste de Rio Claro, SP)

A tectônica Mesozóica-Cenozóica na borda leste da Bacia do Paraná foi interpretada com base no estudo geocronológico de uma importante feição estrutural conhecida como Domo de Pitanga (sudoeste de Rio Claro, SP), que, como outras estruturas do mesmo tipo presentes na borda da bacia, coincide com grandes alinhamentos estruturais formados pela reativação de estruturas preexistentes no seu embasamento. O método utilizado foi o de datação por análise de traços de fissão em apatitas, o qual permite a modelagem térmica entre 120oC e a temperatura ambiente. Utilizando apatitas de rochas sedimentares, foi possível a modelagem da história térmica da área, graças à homogeneidade dos dados que cada amostra apresentou em função do aquecimento no Eocretáceo pelo magmatismo Serra Geral. Além do resfriamento posterior ao magmatismo marcado pelas idades (Eocretáceo), foram detectadas as principais épocas de resfriamento na área de estudo, sendo elas do Neocretáceo, Paleoceno e, com menor importância, do Mioceno. Estes períodos remontam a importantes eventos tectônicos ocorridos no Sudeste brasileiro, bem descritos no embasamento cristalino. Fica clara a influência desta tectônica de caráter ascensional do embasamento adjacente no interior da bacia, atuando na formação de estruturas, como é o caso do Domo de Pitanga.

Intrusão Alcalina de Morro Preto (go): Geologia, Petrografia e Geoquímica

A intrusão alcalina de Morro Preto, localizada ao norte da cidade de Piranhas (GO), corresponde a um corpo irregular a subcircular com aproximados 3,34 km2 alojado em gnaisses atribuídos ao Arco Magmático de Goiás. É constituída principalmente por carbonatitos e lamprófiros com graus variados de laterização e silicificação, além de silexitos e, em menor expressão, por sienito ferruginizado e basalto alcalino. Quimicamente mostram baixas concentrações em Cs, K, Na, Rb e altas concentrações em elementos como TR, Nb, Ba, Th e U. Isto aparenta resultar de processos de laterização/silicificação e da formação de fases minerais raras (ou neoformação de fases minerais), como fosfatos com alta concentração de TR e Th, oxi-hidróxidos de Fe, Ba, Mn, e oxi e/ou silico-fosfatos de ETR, Nb, Ta, dentre outros, e a formação de barita. A presença de rochas carbonatíticas com alto P2O5 e o enriquecimento acentuado em TR sugere a possibilidade de mineralizações destes componentes, similar às observadas em outros complexos alcalinos de Goiás e de Minas Gerais, como Catalão e Araxá. A distribuição de elementos menores, traços e TR mostram que as rochas são produtos de alteração de rochas ígneas alcalinas como carbonatitos, lamprófiros e basaltos alcalinos, rochas já enriquecidas em elementos como Th, U, TR (principalmente em ETRL), Nb e Ta. Os teores anormalmente altos são resultado do processo de enriquecimento supérgeno (processos de intemperismo como silicificação e laterização) e/ou alteração hidrotermal com baixa temperatura.

Fontes de fósforo e torta de filtro sobre o estado nutricional e produtividade da cana-planta

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Cronogeomorfologia do relevo da cidade de Marília através do método de traços de fissão - MTF

Pós-graduação em Geografia - FCT

Long-term landscape evolution and post-rift reactivation in the southeastern Brazilian passive continental margin: Taubat, basin

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

Bacterial Cellulose/Chondroitin Sulfate for Dental Materials Scaffolds

Bacterial cellulose (BC) has become established as a remarkably versatile biomaterial and can be used in a wide variety of scientific applications, especially for medical devices. In this work, the bacterial cellulose fermentation process is modified by the addition of chondroitin sulfate (1% w/w) to the culture medium before the bacteria are inoculated. Besides, biomimetic precipitation of calcium phosphate of biological interest from simulated body fluid on bacterial cellulose was studied. Chondroitin sulfate influences in bacterial cellulose were analyzed using transmission infrared spectroscopy (FTIR), XRD (X-ray diffraction) and scanning electron microscopy (SEM). FTIR analysis showed interaction between chondroitin sulfate, bacterial cellulose and calcium phosphate and XRD demonstrated amorphous calcium phosphate and carbonated apatite on bacterial cellulose nanocomposites. SEM images confirmed incorporation of calcium phosphate in bacterial celluloe nanocomposite surface and uniform spherical calcium phosphate particles. Future experiments with cells adhesion and viability are in course.

Uso de torta de filtro enriquecida com fosfato natural e biofertilizantes em Latossolo Vermelho distrófico

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

Recalibration of U-doped standard glasses through uranium thin film for neutron-fluence measurements

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Bacterial Cellulose Nanobiocomposites for Dental Materials Scaffolds

Bacterial cellulose (BC) has become established as a remarkably versatile biomaterial and can be used in a wide variety of scientific applications, especially for medical devices. In this work, the bacterial cellulose fermentation process is modified by the addition of chondroitin sulfate and hyaluronic acid (1% w/w) to the culture medium before the bacteria is inoculated. Besides, biomimetic precipitation of calcium phosphate of biological interest from simulated body fluid on bacterial cellulose was studied. Chondroitin sulfate and hyaluronic acid effects in bacterial cellulose were analyzed using transmission infrared spectroscopy (FTIR), XRD (X-ray diffraction) and scanning electron microscopy (SEM). FTIR analysis showed interaction between bacterial cellulose nanobiocomposites and calcium phosphate. XRD demonstrated amorphous calcium phosphate, carbonated apatite and calcium chloride on bacterial cellulose nanobiocomposites. Monocalcium phosphate monohydrate phase formation [Ca(H2PO4)(2)center dot H2O] are here attested by FTIR, XRD and Ca/P relation.

Geologia de uma área na porção centro leste da folha Cássia (1:50.000), MG

This study aimed the geological characterization at scale 1:50.000 of an area belonging to the southern sector of the Brasilia Belt, located in the western portion of the Passos Nappe, near the town of Cássia, MG. In this region, outcrops rock types belonging to Araxá Group, composed of metasediments associated with metavolcanics which form a tectonometamorphic terrain of great importance for understanding the geological evolution of southeast and midwest regions of Brazil. With the development of work was possible to group the rocks in 10 lithostratigraphic units and had been identified 3 different zones of metamorphism generated during the peak metamorphism. The structural pattern of the area shows that the main foliation has average dip 30 ° NW and mineral lineation parallel to the stretching direction with 290 °. Still, we can conf irm that this inverse gradient metamorphic rocks of the Passos Nappe, described by several authors. Also, were seen lithotypes of economic interest, some already in exploitation, such as clay and sand, and other mineral commodities, which are occurring and can be used: quartz, quartzite, garnet, kyanite, rutile and zircon.

Caracterização litogeoquímica dos basaltos do município de Monções -SP

The paper deals with the petrographic and geochemical investigation of basalt flows present in a gravel quarry in the town of Monções in northwestern São Paulo State, members of the Serra Geral Formation of the Paraná Basin. Were collected 11 samples from different horizons within a topographic vertical profile with an average of 18 meters in height. The samples were subjected to macroscopic and microscopic petrographic and chemical major, minor and trace. The results indicated that it is tholeiitic basalts with dense fine grained average. Petrographic analyzes show that basalts studied are basically constituted by plagioclase (between 33 and 49%), labradorite and clinopyroxenes (between 29 and 46%) represented by the subordinate pigeonite and augite, having as accessories opaque (between 3 and 15% ), olivine (<2%), apatite and zircon as dashes. The secondary minerals correspond to cloropheite, chlorite, serpentine, epidote, albite and iron oxides and hydroxy as well as bowlingit of clay, nontronite, and celadonite. The basalts are kind of high-titanium (Hti)> 1.8% TiO2, and apparently belong to the Pitanga magma-type. The geochemical analyzes proved unsatisfactory for the determination of a probable lithogeochemistry differentiation within the vertical stroke for generating multiple data correlation or no immediately discernible trends

Evolução da tectônica rúptil no nordeste do Brasil baseada na termocronologia por traço de fissão em apatita

Results of apatite fission tracks from twelve samples collected across a Borborema Province transect, northeastern Brazil, revealed two major paleothermal events: a cooling event occurred between Albian and late Cenomanian (110 - 80 Ma) and a second cooling event starting on early Paleocene (66 Ma). Given the wide expression of the studied area (sampling trend along four brazilian states) a correlation between the distribution of fission track data and the current geological / geomorphological scenario was made possible, considering the area’s tectono - stratigraphic past and its thermochronologic evolution until now. The fact that the employed thermochronologic tool relates to a relatively shallow geothermometer, substancially information for understanding the behavior of basement brittle tectonic was achieved. These data were used to analyze faults origin and reactivation, associated with sedimentary basins evolution in the context of South America - Africa continental breakup.

Análise estrutural e microtectônica da inflexão do jordino e depósitos de ouro associados no greenstone belt de Pilar de Goiás

The study area is included in the geological context of the Goias Median Massif, a region where there are associations of Archean granite-gneiss complex (Block Moquém) and a Paleoproterozoic metavolcano-sedimentary sequence ( Pilar greenstone belt ). At the south of area, the greenstone sequence is partially overlain by Neopreoterozoic metasediments of the Araxá Group. The lithostratigraphic units of the Pilar greenstone belt define a shift from about N30W direction (north of the deposit) to N60 and 70W in the region south of the Jordino deposit, where are truncated by the Araxá Group rocks. Mineralogical associations described in this paper allow to indicate that the regional metamorphism that affected the rocks of the greenstone belt and Araxá Group, in the mapped area, reached the upper greenschist facies (garnet zone). Data obtained during mapping and by microtectonics analysis allow to indicate the existence of at least four deformational events that acted on the rocks of the Guarinos greenstone belt and Araxá Group, represented by the phases called Dn-1, Dn, Dn + 1 and Dn+2. It was observed that the pattern of sulphide porfitoblasts in mineralized levels is similar to garnet, biotite and muscovite porfiroblasts (tardi to post Dn) that marks the metamorphic peak of the area

Crescimeno de apatita na superfície da liga Ti-7, 5Mo empregando tratamento higrotérmico

The objective of the present work was to evaluate surface of experimental alloy Ti-7.5Mo after hydrothermal treatment. Ingots were obtained in arc melting furnace under an argon atmosphere and then homogenized under vacuum at 1100ºC for 86.4 ks to eliminate chemical segregation and after cold worked discs were cutting and grinding. For surface treatment, samples were immersed in a container with NaOH aqueous solution 5M, autoclaved, washed with distilled water. Followed, samples were heat treated and they were soaking in 5xSBF to form an apatite layer on the surface. Surfaces were investigated by, scanning electron microscopy, X-Rays powder diffraction, atomic force microscopy and contact angle, in order to evaluate the wettability of the alloy surface. The results were compared with our previous studies using the group of chemical surface treatments and results shows better condition is 120 minutes in the autoclave

Crescimento de apatita na superfície da liga Ti-25Ta empregando dois tipos de tratamento de superfície: biomimético e deposição de polímero por eletrofiação

Titanium and its alloys has been widely used as materials for metallic biomaterials implants are usually employed to restore the hard tissue function, being used for artificial joints and bones, synthetic plates, crowns, dental implants and screws . Objective of this work was the surface modification of Ti-alloy 25Ta from biomimetic surface treatment of employment and deposition of polymer by electrospinning. The league was obtained from the fusion of the pure elements in the arc furnace with controlled atmosphere. The ingots were subjected to heat treatment, cold forged and sectioned discs with 13 mm diameter and 3 mm thick. Two surface treatments was evaluated, biomimetic and electrospinning with PCL fiber. The biomimetic treatment was performed involving alkaline treatment for three molarities 1.5M, 3M and 5M with immersion in SBF. The electrospinning was performed using PCL polymer alloy surface after the alkali treatment Ti25Ta 1M. For this group the polymer coated surfaces were immersed in calcium phosphate containing solution for immobilization of apatite. The results were compared with previous studies using surface treatment group to verify hydroxyapatite formation on the sample surface and it is concluded that the best condition is biomimetic treatment with 5M alkali treatment and heat treatment at 80 ° C for 72 hours