Anodização para obtenção de membranas cerâmicas

This a study on the achievement of alumina membranes by the method of anodizing. From this method got up a layer of aluminum oxide on the anodic metal, who presented the basic properties necessary for the application as a support for the production and acquisition of nanomaterials, such as porosity nano and resistance to high temperature, and other properties, as resistance to corrosion, and chemical, high ranking of the structure and pore size of the pores. The latter, ranging from 10 to 100nm depended on the electrolyte used, which in this study was the H2SO4. To remove all remaining aluminum, it is a bath of dissolution with HCl and CuCl where the residual aluminum has been withdrawn, and the deep pores were opened after chemical treatment with NaOH. After the dissolution, the membranes were calcined at temperatures of 300, 600 and 900° C, and sintered at temperatures of 1200 and 1300º C to win mechanical strength, porosity and observe the desired crystallization. Then went through analyses of composition through X-ray diffraction and morphology of the microstructure through a scanning electron microscope. The method was effective for obtaining alumine membranes applied in the processes of production of materials in nano

Eletrofiação e caracterização de membranas biopoliméricas a base de quitosana extraídas dos exoesqueletos de crustáceos

Chitin and chitosan are nontoxic, biodegradable and biocompatible polymers produced by renewable natural sources with applications in diverse areas such as: agriculture, textile, pharmaceutical, cosmetics and biomaterials, such as gels, films and other polymeric membranes. Both have attracted greater interest of scientists and researchers as functional polymeric materials. In this context, the objective of this study was to take advantage of the waste of shrimp (Litopenaeus vannamei and Aristeus antennatus) and crabs (Ucides cordatus) from fairs, beach huts and restaurant in Natal/RN for the extraction of chitin and chitosan for the production of membranes by electrospinning process. The extraction was made through demineralization, deproteinization, deodorization and deacetylation. Morphological analyzes (SEM and XRD), Thermal analysis (TG and DTG), Spectroscopy in the Region of the Infrared with Transformed of Fourier (FTIR) analysis Calorimetry Differential Scanning (DSC) and mechanical tests for traction were performed. In (XRD) the semicrystalline structure of chitosan can be verified while the chitin had higher crystallinity. In the thermal analysis showed a dehydration process followed by decomposition, with similar behavior of carbonized material. Chitosan showed temperature of maximum degradation lower than chitin. In the analysis by Differential Scanning Calorimetry (DSC) the curves were coherent to the thermal events of the chitosan membranes. The results obtained with (DD) for chitosan extracted from Litopenaeus vannamei and Aristeus antennatus shrimp were (80.36 and 71.00%) and Ucides cordatus crabs was 74.65%. It can be observed that, with 70:30 solutions (v/v) (TFA/DCM), 60 and 90% CH3COOH, occurred better facilitate the formation of membranes, while 100:00 (v/v) (TFA/DCM) had formation of agglomerates. In relation to the monofilaments diameters of the chitosan membranes, it was noted that the capillary-collector distance of 10 cm and tensions of 25 and 30 kV contributed to the reduction of the diameters of membranes. It was found that the Young s modulus decreases with increasing concentration of chitosan in the membranes. 90% CH3COOH contributed to the increase in the deformation resulting in more flexible material. The membranes with 5% chitosan 70:30 (v/v) (TFA/DCM) had higher tensile strength

Utilização de membranas no pós-tratamento de esgotos para reuso do permeado e aproveitamento do concentrado

The use of membrane filters in the post-treatment of sewage has been increasingly employed to obtain water quality, applicable to various forms of reuse. Despite the advantages presented using the permeate membranes, such as saving water and reducing water pollution, the concentrate generated in the process ends up being an inconvenience to the deployment of this technology due to lack of sustainable solutions for their management. Thus, the main objective of this research was to evaluate the use of membranes for microfiltration, ultrafiltration, nanofiltration and reverse osmosis concentrated in agriculture, using it as liquid fertilizer. The permeated membranes were also assessed in order to identify activities in which they could be reused. Five configurations were established from four types of membranes, so that each configuration represents a different system. The tests were conducted in batch mode, with triplicate for each configuration. The results indicated that permeated the microfiltration and ultrafiltration can be used in urban areas, in non-potable uses. Have the nanofiltration permeate can be reused in the industry, replacement cooling towers, and other non -potable uses required in the manufacturing unit. The permeate obtained in reverse osmosis met the intended uses for nanofiltration as well as the standards required for boiler feed, adding alkalizing being required to raise the pH to the recommended value. Concentrates generated in nanofiltration and reverse osmosis can be availed as liquid fertilizer in agriculture, but they must be diluted in the irrigation water, in order to adjust the salt concentration allowed for the least tolerant crops patterns

Avaliação da remoção de matéria orgânica carbonácea e nitrogenada de águas residuárias em biorreator de membranas

O presente trabalho objetivou a avaliação da remoção de matéria orgânica carbonácea e nitrogenada, bem como a determinação do fluxo crítico, em biorreator de membranas, com zona pré-anóxica, tratando águas residuárias industriais da produção de aminoácidos. O reator foi operado sob carga orgânica volumétrica de 1,91 kg.DQO.m-3.d-1 e 0,18 kg.NTK.m-3.d-1; a recirculação do reator aeróbio para o reator anóxico foi de quatro vezes a vazão afluente. O reator apresentou médias de remoção de DQO, NTK e NT de 97, 98 e 92%, respectivamente. O sistema de ultrafiltração foi testado em vários fluxos entre 25 e 37 L.m-2.h-1 e determinou-se o fluxo crítico de 28 L.m-2.h-1 quando operado com 11,4 g.L-1 de SST e 35 dias de tempo de retenção celular. Os resultados mostraram que houve viabilidade técnica no uso de biorreator de membranas para remoção de matéria orgânica de águas residuárias industriais da produção de aminoácidos.

Preparação de membranas de acetato de celulose organomodificadas para adsorção dos íons Cu(II), Cd(II), Mn(II) e Ni(II)

Cellulose acetate polymeric membranes had been prepared by a procedure of two steps, combining the method of phase inversion and the technique of hydrolysis-deposition. The first step was the preparation of the membrane, and together was organomodified with tetraethylortosilicate and 3-aminopropyltrietoxysilane. Parameters that exert influence in the complexation of the metallic ion, as pH, time of complexation, metal concentration, had been studied in laboratory using tests of metal removal. The membranes had presented resistance mechanics and reactivity to cations, being able to be an alternative for the removal, daily pay-concentration or in the study of the lability of metals complexed.

Membranas de quitosana micro e macroporosas : preparo, caracterização e estudos de permeabilidade

Two methodologies were proposed to obtain micro and macroporous chitosan membranes, using two different porogenic agents. The methodologies proved to be effective in control the porosity as well as the pore size. Thus, microporous membranes were obtained through the physical blend of chitosan and polyethylene oxide (PEO) on an 80:20 (m/m) ratio, respectively, followed by the partial PEO solubilization in water at 80 ◦C. Macroporous chitosan membranes with asymmetric morphology were obtained using SiO2 as the porogenic agent. In this case, chiotsan-silica ratios used were 1:1, 1:3 and 1:5 (m/m). Membranes characterization were carried out by SEM (scanning electronic microscopy), X-ray diffraction, Fourier Transform Infrared Spectroscopy (FTIR), Thermal analysis (TG, DTG , DSC and DMTA). Permeability studies were performed using two model drugs: sodium sulfamerazine and sulfametoxipyridazine. By transmission FTIR it was possible to confirm the complete removal of SiO2. The SEM images confirmed the porous formation for both micro and macroporous membranes and also determined their respective sizes. By thermal analysis it was possible to show differences related with water sorption capacity as well as thermal stability for both membranes. DTG and DSC allowed evidencing the PEO presence on microporous membranes. The absorbance x time curves obtained on permeability tests for micro and macroporous membranes showed a linear behavior for both drugs in all range of concentration used. It was also observed, through P versus C curves, an increase in permeability of macroporous membranes according to the increase in porosity and also a decrease on P with increase in drug concentration. The influences of the drug molecular structure, as well as test temperatures were also evaluated

Síntese e caracterização de membranas zeolíticas tipo mfi e aplicação em separação de aromáticos

The synthesis of MFI-type zeolite membranes was carried by the process in situ or hydrothermal crystallization. We studied the homogenization time of the room temperature and gel filtration just before the crystallization step performed out in an oven, thus obtaining a more uniform zeolite film. The powder synthesized zeolite (structure type MFI, Silicalite) was characterized by several complementary techniques such as Xray diffraction (XRD), scanning electron microscopy (SEM), thermal analysis, temperature programmed desorption (TPD), Fourier Transform infrared spectroscopy (FTIR) and textural analysis by nitrogen adsorption (specific surface area). For the purpose of evaluating the quality of the layer supported on the ceramic support, N2 permeation tests were carried starting from room temperature to 600 °C, where values were observed values more appropriate permeation from 200 °C. With the data obtained, it was made into a graph of temperature versus permeation function, the curve of surface diffusion was found. For scanning electron microscopy, we observed the formation of homogeneous crystals and the zeolite film showed no fissures or cracks, indicating that the process of synthesis and subsequent treatments not damaged the zeolite layer on the support. Carried permeation studies were found values ranging from 3.64x10-6 to 3.78x10-6, 4.71x10-6 to 5.02x10-6, to pressures 20 and 25 psi, respectively. And the mixture xylenes/N2 values were between 5.39x10-6 to 5.67x10-6 and 8.13x10-6 to 8.36x10-6, also for pressures of 20 and 25 psi. The values found for the separation factor were 15.22 at 400 °C in the first experiment and 1.64 for the second experiment at a temperature of 150 °C. It is concluded that the Silicalite membrane was successfully synthesized and that it is effective in the separation of binary mixtures of xylenes

Preparo e caracterização de membranas de quitosana modificadas com poli (ácido acrílico)

The aim of this study was to generate an asymmetric biocompactible and biodegradable chitosan membrane modified by the contact with a poly(acrylic acid) solution at one of its sides at room temperature and 60◦C. The pure chitosan membrane, as well as the ones treated with poly(acrylic acid) were characterized by infrared spectroscopy (FTIRATR) at angles of 39◦, 45◦ and 60◦ , swelling capacity in water, thermal analysis (TG/DTG), scanning electronic microscopy (SEM) and permeation experiments using metronidazole at 0,1% and 0,2% as a model drug. The results confirmed the presence of ionic interaction between chitosan and poly(acrylic acid) by means of a polyelectrolyte complex (PEC) formation. They also showed that such interactions were more effective at 60◦C since this temperature is above the chitosan glass transition temperature wich makes the diffusion of poly(acrylic acid) easier, and that the two treated membranes were asymmetrics, more thermically stable and less permeable in relation to metronidazole than the pure chitosan membrane

Rotura gástrica por barotrauma

Barogenic rupture of the stomach is a rare complication following cardiopulmonary resuscitation, administration of nasal oxygen by catheter and diving accidents. We report a case of gastric barotrauma following oroesophageal intubation. In most cases, the tears occur along the lesser curvature, what have been already attributed to Laplace's formula and, more recently, to morphological features of the stomach.

Efeito da frequência de amamentação sobre a taxa de ovulação após tratamento com desmame temporário + GnRH, sobre a incidência de luteólise prematura no primeiro ciclo estral pós-parto e sobre o desempenho da progênie de vacas Nelore

Avaliou-se o efeito da restrição na frequência de amamentação sobre o diâmetro folicular no dia 0 (DFOL), sobre a taxa de ovulação (TO), e sobre a incidência de luteólise prematura no primeiro ciclo estral pós-parto (ILP) de vacas Nelore multíparas, em anestro, submetidas à amamentação ad libitum (controle; n= 115) ou amamentação uma vez ao dia (restrito; n= 109), entre os dias -14 e 9 do experimento, e estudou-se o efeito desses tratamentos sobre o peso à desmama da progênie dessas vacas. Induziu-se ovulação com remoção de bezerros entre os dias -2 e 0 e aplicação de 100μg de GnRH no dia 0. Somente animais que ovularam foram mantidos no experimento (n= 125). A ocorrência de luteólise prematura foi avaliada por meio da dosagem da concentração sérica de progesterona nos dias 5 e 9. A TO não foi influenciada pelos tratamentos (55,8%; P>0,1), e as vacas do tratamento restrito apresentaram maior DFOL (10,90±0,26 vs. 10,18±0,21mm; P<0,05) e menor ILP (21,4% vs. 43,5%; P<0,05). Os bezerros do tratamento controle foram mais pesados (162,32±2,08 vs. 155,91±4,12kg; P<0,05). Conclui-se que a restrição na frequência de amamentação em vacas Nelore reduz a ILP, porém com possível efeito negativo no desenvolvimento dos bezerros.

Desenvolvimento, produtividade e sobrevivência de maracujazeiro-amarelo enxertado e cultivado em área com histórico de morte prematura de plantas

O objetivo deste trabalho foi avaliar o desenvolvimento vegetativo, a produtividade e a sobrevivência do maracujazeiro-amarelo (Passiflora edulis Sims) enxertado sobre três porta-enxertos, em área com histórico de morte prematura de plantas. O experimento foi conduzido no município de Adamantina-SP, no período de maio de 2006 a fevereiro de 2007, adotando-se o delineamento de blocos ao acaso, com três tratamentos e sete repetições. Os porta-enxertos avaliados foram Passiflora edulis, P. alata e P. gibertii, utilizando-se da enxertia convencional por garfagem tipo fenda cheia. Avaliaram-se o diâmetro do caule do porta-enxerto e do enxerto, o comprimento do entrenó e dos ramos secundários, o número de ramos terciários e o de frutos, a massa média, o diâmetro e o comprimento médio dos frutos, a produtividade e a sobrevivência de plantas. Os resultados demonstraram que o uso da enxertia no maracujazeiro é uma opção viável como meio de propagação vegetativa, assim como forma de controle de alguns patógenos habitantes do solo, um dos problemas que têm limitado a expansão da cultura. As plantas enxertadas sobre P. edulis apresentaram melhor desenvolvimento inicial, seguido de P. gibertii e de P. alata. A menor produtividade ocorrreu em plantas sobre P. alata. Mesmo com a presença de Fusarium solani e Rotylenchulus reniformis nos solos, 91% das plantas enxertadas sobre P. gibertii sobreviveram após 12 meses de plantio no campo, enquanto em P. alata e P. edulis, esses índices foram de 60% e 8,6%, respectivamente, mostrando assim a maior tolerância às doenças causadas por patógenos habitantes do solo por P. gibertii.

Anestésicos locais: interação com membranas biológicas e com o canal de sódio voltagem-dependente

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

Caracterização das membranas fetais em búfalas no terço inicial da gestação

Este estudo visou à caracterização das membranas fetais em búfalas (Bubalus bubalis, Linnaeus 1758) no terço inicial da gestação. As membranas fetais foram analisadas macroscópica e microscopicamente (luz e microscopia eletrônica de transmissão). O córion possui uma camada simples de células circulares, com núcleos de forma esférica, denominadas trofobláticas; há outro tipo celular, as células trofoblásticas gigantes, com dois ou mais núcleos. Ambas possuem uma grande quantidade de vesículas no citoplasma e retículo endoplasmático à microscopia de transmissão. O alantóide possui vasos preenchidos com eritrócitos, e contêm células alongadas, que formam um epitélio estratificado simples. O âmnion é uma membrana transparente, ou esbranquiçada; constituído por epitélio estratificado simples. A diferença principal entre o alantóide e o âmnion é que o último é avascular. O saco vitelínico é uma membrana opaca que desaparece durante a gestação; é a única membrana que não está em contato com as outras e apresenta três tipos diferentes de células que dão forma a três camadas distintas (endoderma, mesotélio, mesênquima).

Histologia da associação de membranas biológicas de origem bovina implantadas no subcutâneo de ratos

O trabalho teve por objetivo avaliar a capacidade de barreira da membrana de cortical óssea desmineralizada liofilizada bovina, testando sua permeabilidade e integridade, em associação com a membrana de pericárdio bovino liofilizado. em 15 ratos Wistar, machos, adultos, implantou-se no subcutâneo da região cérvico-torácica dorsal a combinação de duas membranas de cortical óssea desmineralizada tendo no interior a membrana de pericárdio bovino. Os animais (cinco ratos/grupo) foram submetidos à eutanásia aos 15, 30 e 60 dias de pós-operatório. A avaliação microscópica mostrou que, aos 15 dias de pós-cirúrgico, as membranas estavam íntegras, com exceção de pequenas áreas de reabsorção da membrana de cortical óssea junto aos locais referentes aos antigos canais nutritivos. Aos 30 dias, havia apenas restos da membrana de cortical óssea e, aos 60 dias, a sua total ausência. Baseados nos resultados aqui obtidos, é possível concluir que a membrana de cortical óssea bovina é rapidamente absorvida e não confere proteção à membrana de pericárdio bovino liofilizado.

Seguimiento multidisciplinario en el control del penfigoide de membranas mucosas

The term Mucous Membrane Pemphigoid includes a group of chronic and autoimmune vesiculobullous diseases involving mainly the mucosa. The aim of present paper is to describe two clinical cases of Mucous Membrane Pemphigoid with gingival involvement to arrive to a proper diagnosis of the lesion and also to discuss the therapeutic behavior. Different complementary examinations were conducted including Nikolsky test, incisional biopsy, the LE cells study and of antinuclear antibodies, as well as the evaluation of dermatologists and ophthalmologists. It was necessary the replacement of toothpastes, the nutritional and psychological guiding, the hygiene care and the use of topic corticoids. There were periods of remission and exacerbation of clinical picture during follow-up being necessary the therapeutics fitting and the oral hygiene care reinforcement. It is important the multidisciplinary interaction in the care of these cases for treatment and follow-up control, as well as to reinforce all orientations and cares related to oral hygiene and the caution in the use of corticoids.