Resumo em inglês The metal ions removal on cashew bagasse, a low-cost material, has been studied by batch adsorption. The parameters chemical treatment, particle size, biosorbent concentration, and initial pH were studied. In this study the maximum ions removal was obtained on the cashew bagasse treated with 0.1 mol/L NaOH/3 h, at optimum particle size (20-59 mesh), biosorbent concentration (50 g/L) and initial solution pH 5. The kinetic study indicated that the adsorption metal follows p (mais) seudo-second order model for a multielementary system and equilibrium time was achieved in 60 min for all metal ions.
Resumo em inglês Fixed-bed column studies were undertaken to evaluate the performance of a commercial Brazilian activated carbon in removing Pb(II) from aqueous environment. Breakthrough points were found out for the metal adsorption by varying different operating parameters like feed concentrations (10 and 20 mg L-1) and bed heights (0.5, 1.5 and 2.8 cm). A good agreement was observed between the experimental data and the values predicted by the bed depth service time (BDST) model. Regen (mais) eration of the exhausted columns was possible with HCl, and the adsorption capacity was maintained after three adsorption-desorption cycles.
Resumo em inglês This review had as aim the bibliography research for the use of aluminosilicates to remove heavy metals from wastewaters. Advanced studies based on parameters that have influence for removal of heavy metals as pH, metal concentration, effect of ligants and removal capacity of zeolites and clays, were reported. These studies demonstrate that aluminosilicates can be successfully used for the removal of heavy metals under the optimized conditions.
Resumo em inglês The present study consists in evaluating the NaX zeolite efficiency in removing Cu2+ from aqueous solutions, for future use of NaX in removing metals from wastewaters. The experiments were performed in batch systems (with shaking and continous stirring) and for different time intervals (1 to 24 h). Three particle sizes were employed: (mais) particle size plays an important role in the adsorption process. Specifically, NaX zeolites of smaller particle size achieved the maximum adsorption capacity of 152.36 mg of Cu2+/g of zeolite at pH = 4.5.
Resumo em inglês Adsorption of heavy metal cations by activated carbon is dependent on the capacity of the material in promoting adsorption and the time needed to reach equilibrium. Carbon samples were previously activated either by phosphoric acid treatment at 400 ºC or by steam at 800 ºC. The results of Pb(II) adsorption by these activated carbons have shown that equilibrium was typically reached within the first 5 min of contact between carbon and metal solution, with a maximum adsor (mais) ption capacity higher than 69 mg g-1 for the vapor-activated sample. Temperature influences the sorption capacity, which corresponds to an endothermic process. Lead(II) retention is more pronounced at high temperature and low pH.
Resumo em português TEMA: hábitos prolongados de sucção de chupeta e mamadeira podem provocar distúrbios miofuncionais como o padrão incorreto de deglutição e repouso lingual. OBJETIVO: estudar os efeitos da associação da Terapia Miofuncional (TMF) e da remoção de hábitos (REM) de sucção na reabilitação da deglutição e repouso lingual. MÉTODO: dois grupos composto por dez crianças de quatro anos a quatro anos e oito meses de idade que inicialmente apresentavam hábitos de (mais) sucção de chupeta e mamadeira foram estudados. O grupo denominado REM foi submetido à REM pelo Método de Esclarecimento modificado, enquanto que o grupo denominado TMF também teve os hábitos de sucção removidos pelo mesmo método e foi associada a TMF. Foram realizados exames pré-tratamento, 60 e 180 dias pós-procedimentos. Os dados foram submetidos aos testes estatísticos de Mann-Whitney e Wilcoxon p Resumo em inglês BACKGROUND: the prolonged habit of pacifier sucking and the prolonged use of feeding bottle may cause myofunctional disorder, such as incorrect swallowing pattern and inadequate tongue rest position. AIM: to study the effect of myofunctional therapy (MFT) associated with the removal of the habit of pacifier sucking and the use of feeding bottle (REM) on the rehabilitation of swallowing and tongue rest position. METHOD: two groups with ten children, ages ranging from four (mais) to four years and eight months, who initially presented a pacifier sucking habit and used the feeding bottle were studied. Children on REM group underwent the process of sucking habits removal using the Modified- Counselling Method, whereas children on MFT group underwent the same procedure associated to myofunctional therapy. Pre-treatment assessments were made, as well as 60 and 180 days post-treatment assessments. Data were analyzed using the statistical tests of Mann-Whitney and Wilcoxon (p
Remoção de íons Zn2+, Cd2+ e Pb2+ de soluções aquosas usando compósito magnético de zeólita de cinzas de carvão/ Removal of Zn2+, Cd2+ e Pb2+ ions from aqueous solutions by magnetic composite of zeolite from coal ashes
Resumo em inglês For this study, magnetic composite of zeolite-magnetite was prepared by mixing magnetite nanoparticles suspension with synthetic zeolite. The nanoparticles in suspension were synthesized by precipitating iron ions in a NaOH solution. The zeolite was synthesized from coal fly ash by alkaline hydrothermal treatment. The magnetic composite was characterized by XDR, SEM, magnetization measurements, IR, and BET surface area. Batch tests were carried out to investigate the adso (mais) rption of metal ions of Zn2+, Cd2+ and Pb2+ from aqueous solution onto magnetic composite. Adsorption isotherms were analyzed using Freundlich and Langmuir equations. The adsorption equilibrium data fitted well to the Langmuir equation with maximum adsorption capacities in the range of 28.5-127 mg g-1.
Remoção biológica de fósforo em reatores em bateladas sequenciais com diferentes tempos de retenção de sólidos/ Biological phosphorus removal in sequencing batch reactors with different solid retention times
Resumo em português Nos últimos anos, tem surgido a necessidade de se projetarem sistemas de tratamento de águas residuárias que, além de remover carga orgânica, sejam capazes de remover nutrientes, particularmente nitrogênio e fósforo. Este trabalho avaliou a remoção biológica de fósforo em sistemas de lodo ativado, tratando esgoto doméstico por meio de reatores em bateladas sequenciais (RBS), monitorado com diferentes tempos de retenção celular (TRC): 20, 5 e 3 dias. Esses ex (mais) perimentos foram avaliados em escala de bancada com o uso da respirometria, utilizando-se acetato como fonte de carbono orgânico. Os resultados mostraram satisfatória remoção de fósforo total nos três experimentos, com valores médios entre 79 a 82%, sendo que o sistema RBS que operou com TRC de cinco dias obteve resultados melhores. Resumo em inglês In recent years, there has been an increasing need to design wastewater treatment systems that are capable of removing both organic material and nutrients, notably nitrogen and phosphorus. This study evaluated biological phosphorus removal by activated sludge systems fed with domestic sewage and operating as sequencing batch reactors (SBR) with different solids retention times (SRT) namely 20, 5 and 3 days. This was supported by respirometry experiments at bench scale usi (mais) ng acetate as the source of organic carbon. The results showed satisfactory total phosphorus removal efficiencies mean values between 79-82% for the three regimes with the best removal efficiency occurring in the SBR operating with a five-day SRT.
Remoção de compostos tóxicos de solução aquosa por adsorção com zeólita sintetizada a partir de cinzas de carvão/ Removal of toxics compounds from aqueous solution by adsorption with zeolite synthesized from coal ashes
Resumo em português A capacidade das zeólitas sintetizadas a partir da cinza de carvão brasileiro na remoção dos íons de Cd, Zn e do azul de metileno de soluções aquosas foi investigada. O material zeolítico preparado com a cinza de carvão do filtro manga apresentou a eficiência de remoção mais alta para os poluentes. A seletividade aos íons metálicos deste produto foi determinada como: Cd2+ > Zn2+. As capacidades máximas de adsorção encontradas foram 36,1 mg g-1 para o Zn2+, 76,3 mg g-1 para o Cd2+e 3,93 mg g-1 para o corante. Resumo em inglês The capacity of synthesized zeolites from Brazilian coal ash for the removal of Cd, Zn ions and methylene blue from aqueous solutions has been investigated. The zeolitic material prepared with coal ash from baghouse filter showed the highest efficiency for pollutants removal. The metal ion selectivity of this product was determined as: Cd2+ > Zn2+. The maximum sorption capacities found were 36.1 mg g-1 for Zn2+, 76.3 mg g-1 for Cd2+ and 3.93 mg g-1 for dye.
Remoção do íon amônio de águas produzidas na exploração de petróleo em áreas offshore por adsorção em clinoptilolita/ Removal of ammonium ions from waters produced in petroleum offshore exploitation by adsorption on clinoptilolite
Resumo em inglês This work describes the use of clinoptilolite for removal of ammonium ions present in waters produced at the Campos' Basin. Samples were previously treated in order to remove organic compounds and metals. Experiments were run in fixed- and fluidized-bed systems, at room temperature. The fluidized-bed systems did not remove efficiently the ammonium ion. The best operational conditions were obtained with clinoptilolite particle size in the range 0.30-0.50 mm, under ascendan (mais) t flow (3 mL min-1), in a fixed-bed system. The best zeolite performance was found when it was pretreated with 0.5 mol L-1 NaOH. Na+ was the most important interfering ion due to its high concentration in the water. Clinoptilolite lost partially its capacity to retain ammonium ions after several regeneration cycles with NaOH.
Remoção de azul de metileno de solução aquosa usando zeólitas sintetizadas com amostras de cinzas de carvão diferentes/ Removal of methylene blue from aqueous solution using zeolite synthesized from different coal fly ashes samples
Resumo em inglês Batch sorption experiments were carried out to remove methylene blue from its aqueous solutions using zeolites synthesized from fly ashes as an adsorbent. The adsorbents were characterized by XFR, XRD and SEM. Nearly 90 min of contact time are found to be sufficient for the adsorption of dye to reach equilibrium. Equilibrium data have been analyzed using Langmuir and Freundlich isotherms and the results were found to be well represented by the Freundlich isotherm equation (mais) . Adsorption data were fitted to both Lagergren first-order and pseudo-second-order kinetic models and the data were found to follow pseudo-second-order kinetics.
Remoção de metais pesados de efluentes aquosos pela zeólita natural escolecita - influência da temperatura e do pH na adsorção em sistemas monoelementares/ Heavy metals removal from wastewater by the natural zeolite scolecite - temperature and pH influence in single-metal solutions
Resumo em inglês Cation exchange capabilities of a Brazilian natural zeolite, identified as scolecite, were evaluated for application in wastewater control. We investigated the process of sorption of chromium(III), nickel(II), cadmium(II) and manganese(II) in synthetic aqueous effluents, including adsorption isotherms of single-metal solutions. The natural zeolite showed the ability to take up the tested heavy metals in the order Cr(III) > Cd(II) > Ni(II) > Mn(II), and this could be relat (mais) ed to the valence and the hydration radius of the metal cations. The influence of temperature (25, 40 and 60 ºC) and initial pH value (from 4 to 6) was also evaluated. It was found that the adsorption increased substantially when the temperature was raised to 60 ºC and that maximum adsorption capacity was observed at pH 6. These results demonstrate that scolecite can be used for removal of heavy metals from aqueous effluents, under optimized conditions.
Remoção de Pb2+ e Cr3+ em solução por zeólitas naturais associadas a rochas eruptivas da formação serra geral, bacia sedimentar do Paraná/ Removal of Pb2+ and Cr3+ from aqueous solution by natural zeolites associated with eruptive rocks from the serra geral formation, Paraná sedimentary basin
Resumo em inglês The capacity of natural zeolites and its host rock (dacite) to remove Pb2+ and Cr3+ from aqueous solutions has been investigated. Results showed that both samples prefer to remove Pb2+ instead of Cr3+. Almost 100% of Pb2+ was removed from solutions with concentration until 50 mg L-1 and 100 mg L-1 of this metal, respectively by dacite and zeolite. The equilibrium of metals adsorption process was reached during the first 30 min by both materials. Na+ can be used to recover Pb2+, but not to remove Cr3+ from the treated samples. The Sips model showed a good fit for experimental data of this study.
Remoção de compostos orgânicos em água empregando carvão ativado impregnado com óxido de ferro: ação combinada de adsorção e oxidação em presença de H2O2/ Removal of organic compounds from water by activated carbon impregnated with iron oxide: combined action of adsorption and oxidation in the presence of H2O2
Resumo em inglês In this work, composites based on activated carbon/iron oxide (AC/Fe) were prepared in two different proportions (AC/Fe 5/1 and 1/1) and evaluated in the removal of the organic dye methylene blue (MB). Physical-chemical properties of the composites were determined by X-ray diffraction (XRD), adsorption/dessorption of N2 isotherm, temperature programmed reduction (TPR) and scanning electron microscopy (SEM). Results showed that goethite (α- FeOOH), with nanometer part (mais) icle size, was formed over carbon surface for both composites. These materials showed high efficiency to remove MB from solution by combined adsorption and oxidation process. The AC/Fe 1/1 showed to be more active in (MB) oxidation then AC/Fe 5/1.
Impacto da remoção de plântulas sobre a estrutura da comunidade regenerante de Floresta Estacional Semidecidual/ Impact of seedling removal on regenerating community structure of a seasonal semideciduous forest
Resumo em português O transplante de plântulas e indivíduos jovens de florestas naturais tem sido considerado como alternativa à produção de mudas de espécies nativas para a restauração florestal, sem que tenham sido realizados estudos sobre os possíveis impactos dessa prática sobre a comunidade vegetal regenerante. Nesse trabalho foram analisadas diferentes intensidades de retirada de plântulas e indivíduos jovens de até 30 cm, de remanescente de Floresta Estacional Semidecidua (mais) l, a fim de verificar o quanto essa operação pode comprometer a estabilidade da comunidade regenerante. Foram instaladas 80 parcelas de 2×2 m, distribuídas em dois ambientes (borda e interior da floresta) e em quatro tratamentos de retirada de regenerantes (I,II - 100% de retirada com ou sem revolvimento do solo, III - 50% de retirada sem revolvimento do solo e IV - testemunha sem retirada de regenerantes). Avaliou-se a densidade e a riqueza da regeneração antes da execução dos tratamentos e após seis, 12 e 18 meses. Os resultados foram comparados entre tratamentos para cada período de avaliação e entre períodos de avaliação para cada tratamento. Foram constatadas semelhanças entre borda e interior. Não houve incremento da regeneração com revolvimento do solo. Parcelas submetidas à retirada dos regenerantes recuperaram em parte a densidade; porém apresentaram riqueza menor quando comparadas à testemunha e aos valores iniciais antes da execução dos tratamentos. A remoção das plântulas pode comprometer a regeneração de espécies que ocorrem em baixa densidade, o que sugere que a utilização da regeneração natural como fonte de mudas para a restauração florestal seja voltada para espécies abundantes e com estratégias de regeneração conhecidas e não para a comunidade como um todo. Resumo em inglês Transplanting seedlings and saplings from natural forests has been considered an alternative to producing saplings of native species for forest restoration purposes, but the possible impact of this procedure on plant community regeneration has not been investigated. This work evaluates the impact of different treatments of shrub and tree-seedling (up to 30 cm) removal from a seasonal semideciduous forest fragment located in southeastern Brazil on the natural regeneration (mais) process. Eighty 2×2 m plots were installed in two habitats (forest edge and interior) and submitted to four seedling-removal treatments (I, II - 100% removal with or without soil mixing; III - 50% removal without soil mixing; and IV - control treatment without seedling removal). Regeneration density and richness were evaluated before treatment as well as 6, 12 and 18 months later. The results were compared among treatments for each evaluation period and among periods within treatments. There were similarities between edge and interior. The natural regeneration process did not improve with soil mixing. Plots submitted to seedling removal partially recovered plant density; however, these plots had lower species richness when compared to the control and to the initial values before treatment. Seedling removal has a negative impact on the regeneration process of low-density species, thus the use of natural regeneration as a sapling source for forest restoration purposes should focus only on high-density species with well-known regeneration strategies and not on the community as a whole.
Bioprocessos para remoção de dióxido de carbono e óxido de nitrogênio por micro-algas visando a utilização de gases gerados durante a combustão do carvão/ Bioprocesses for removal of carbon dioxide and nitrogen oxide by microalgae for the utilization of gas generated during coal burning
Resumo em inglês The aim of this work was to study the removal of CO2 and NO by microalgae and to evaluate the kinetic characteristics of the cultures. Spirulina sp. showed µmax and Xmax (0.11 d-1, 1.11 g L-1 d-1) when treated with CO2 and NaNO3. The maximum CO2 removal was 22.97% for S. obliquus treated with KNO3 and atmospheric CO2. The S. obliquus showed maximum NO removal (21.30%) when treated with NO and CO2. Coupling the cultivation of these microalgae with the removal of CO2 and NO has the potential not only to reduce the costs of culture media but also to offset carbon and nitrogen emissions.
Consequências da remoção do limbo foliar em diferentes estádios reprodutivos da cultura do milho em duas épocas de semeadura/ Consequences of maize blade removal in different reproductive stages at two sowing times
Resumo em português Em áreas tropicais há poucas informações disponíveis sobre o efeito da desfolha em milho, principalmente quando ocorre no período do enchimento de grãos. Objetivou-se neste trabalho avaliar os efeitos da remoção do limbo foliar durante o período de enchimento de grãos. Os experimentos foram instalados em 12/11/2005 e 21/12/2005 utilizando-se os híbridos GNZ 2004 e P 30F33. O delineamento experimental utilizado foi o de blocos casualizados com três repetiçõe (mais) s, em esquema fatorial, sendo duas posições de desfolha (acima e abaixo da espiga), duas porcentagens de desfolha (50% e 100%) e quatro estádios reprodutivos (R1, R2, R3 e R4), mais um tratamento adicional, no qual não foi realizada a retirada das folhas. A remoção do limbo foliar acima da espiga resultou em maiores perdas na produção de grãos em relação à remoção do limbo abaixo da espiga. O efeito da remoção do limbo foliar não variou com os estádios fenológicos considerados. Os efeitos na produtividade de grãos, da remoção do limbo foliar abaixo da espiga foram similares à remoção de 50% do limbo foliar acima da espiga em todos estádios fenológicos considerados. O efeito da remoção do limbo foliar sobre a porcentagem de plantas acamadas e quebradas foi de pequena magnitude. Resumo em inglês There is little information, in tropical areas concerning the effects of blade removal on maize crop characteristics. The aim of this research was to evaluate the effects of defoliation during the grain filling period. The experiment was arranged as a factorial complete randomized block design with blade removal at two different plant insertion points (above and below corn ear), with two percentages of blade removal (50% and 100%), and four phenological stages (R1, R2, R3 (mais) , and R4). There were three blocks. Two identical experiments were installed, in 12/11/2005 and 21/12/2005. The hybrids GNZ 2004 and P 30F33 were evaluated in both experiments. Blade removal treatment above corn ear promoted higher grain yield loss in all reproductive stages in relation to the blade removal below corn ear. Blade removal treatment did not change with phenological stages. Results of blade removal below corn ear were similar to 50% of defoliation treatment above the ear. In addition, corn plant lodging was little affected by manual blade removal.
Processo alternativo para remoção de cobre (II) e níquel (II) de soluções aquosas utilizando cápsulas de quitosana - Álcool Polivinílico/ Alternative process for removal of copper and nickel in aqueous solutions, using chitosan - poly(Vinyl Alcohol) capsules
Resumo em inglês Capsules were prepared from chitosan (QTS)-poly(vinyl alcohol) (PVA) blend by saline coacervation and then by formalization. A adsorbent based on chitosan, insoluble on acid solution, was obtained. The morphology, average diameters of QTS/PVA capsules and their pores were studied by using scanning electron microscopy. The entrapment-adsorption of dimethylglioxime and ethylenediaminetetracetate by the capsules were studied. The removal of the ion nickel (II) and copper (II), was more effective than by using unloaded capsules.
Resumo em português Os óxidos de nitrogênio e a amônia são os mais importantes compostos gasosos nitrogenados emitidos para a atmosfera e possuem grande interesse ambiental. Na atmosfera, esses compostos podem sofrer diversas reações resultando em mudanças nas propriedades químicas e físicas da atmosfera. Atividades humanas, principalmente relacionadas com produção de alimentos, energia e uso de fertilizantes têm aumentado as emissões dessas espécies nitrogenadas para o ambient (mais) e, causando distúrbios no seu ciclo natural. Com o objetivo de avaliar as variações dos níveis de concentração e inferir sobre os processos de remoção de compostos de nitrogênio da atmosfera na região de Araraquara, foram feitas determinações em paralelo de amônia (NH3) e dióxido de nitrogênio (NO2). Os resultados de concentração mostraram a estreita correlação entre esses compostos na atmosfera, que sugerem diferentes processos de remoção em diferentes épocas do ano. Resumo em inglês Nitrogen oxides and ammonia are important nitrogen compounds which are emitted to the atmosphere. They are very important substances in the environment. In the atmosphere, these substances may undergo diverse reactions that result in changes of chemical and physical atmosphere's property. Atmospheric removal mechanisms of nitrogen substances may ocurr either dry deposition or wet deposition. Human activity such as food production, energy and fertilizer have increased the (mais) nitrogen emissons to environment, causing disturbances in the natural nitrogen cicle. Parallel determinations of ammonia (NH3) and nitrogen dioxide (NO2) were made to assess variations of concentration and to infer about removal processes theses nitrogen compounds of Araraquara's atmosphere. Results showed the narrow relationship between these substances in the studied atmosphere. This relationship between ammonia and nitrogen dioxide suggested different removal processes at different periods during the year.
Otimização de processos físico-químicos na remoção de fósforo de esgotos sanitários por processos de precipitação química com cloreto férrico/ Physical-chemical process optimization for phosphorus removal from domestic wastewater by chemical precipitation with ferric chloride
Resumo em português Tendo em vista a potencialidade do emprego de processos de coagulação química no tratamento de esgotos, este trabalho teve por objetivo estudar a remoção de fósforo em efluentes de sistemas anaeróbios e aeróbios de tratamento de esgotos. Observou-se que foi possível atingir valores de remoção de fósforo da ordem de 90%, sendo que as dosagens de coagulante se situaram em torno de 60 a 100 mg FeCl3/L. Concomitantemente com a remoção de fósforo, foi também ob (mais) servada uma remoção de carbono orgânico dissolvido (COD) para os efluentes investigados, sendo que as dosagens de coagulante que permitiram a otimização da remoção de fósforo também possibilitaram a otimização da remoção de COD. Justifica-se a remoção de fósforo na forma orgânica e de polifosfatos pelo fato destes estarem associados ao COD removido. Resumo em inglês Since chemical coagulation processes are very promising for wastewater treatment, this work looked into phosphorus removal from aerobic and anaerobic systems treating domestic wastewater. It was possible to reach phosphorus removal efficiencies in the order of 90 % for coagulant dosages in the range 60 to 100 mg of ferric chloride per liter. Dissolved organic carbon (DOC) removal in parallel with phosphorus removal was observed for the previously mentioned treatment syste (mais) m effluents. The coagulant dosages for optimized phosphorus removal also led to optimum DOC removal. The removal of organic phosphorus fractions as polyphosphates was justified due its association with the DOC removal by chemical precipitation.
Resumo em inglês Activities related to nuclear industry, production of phosphoric acid and hospitals have generated considerable volumes of radioactive waste containing uranyl ions. Banana pith was characterized by Scanning Electron Microscopy and Fourier Transform Infrared Spectroscopy and was investigated as a biosorbent for uranyl ions from nitric solutions by batch experiments. Influences of adsorbent size, kinetics and equilibrium adsorption were studied. The biosorption of the urany (mais) l ions followed pseudo-second-order kinetics. The adsorption isotherm data were closely fitted to the Freundlich equation.
Rejeito de mineração de carvão como adsorvente para remoção da acidez, Fe (III), Al (III) e Mn (II) em drenagem ácida/ Coal mining waste as adsorbent for removal of acidity, Fe (III), Al (III) and Mn (II) in acid drainage
Resumo em inglês This study aimed the use of coal mining waste as a new adsorbent for H3O+ and removal of Al (III), Fe (III) and Mn (II) from acid mine drainage. Data from kinetic and equilibrium of the adsorption of H3O+ followed the pseudo second-order and Langmuir isotherm models. The maximum adsorption capacity of H3O+ was 316 mmol kg-1. The adsorbent removed 100% of Al (III), 100% of Fe (III) and 89% of Mn (II), suggesting its use as an alternative for the treatment of acid mine drainage.
Análise comparativa da cirurgia do buraco macular associada à remoção da membrana limitante interna com e sem coloração pela indocianina verde/ Comparative analysis of macular hole surgery followed by internal limiting membrane removal with and without indocyanine green staining
Resumo em português OBJETIVO: Descrever comparativamente os resultados da cirurgia do buraco macular associada à remoção da membrana limitante interna com e sem a coloração pela indocianina verde. MÉTODOS: Foram avaliadas 142 cirurgias consecutivas de buraco macular com remoção de membrana limitante interna realizadas no período de janeiro de 2001 a março de 2004. Estas foram divididas em dois grupos, baseados no uso ou não da coloração da membrana limitante interna pela indocia (mais) nina verde. RESULTADOS: Os grupos estudados foram semelhantes no que diz respeito ao perfil dos pacientes e estágio pré-operatório dos buracos maculares. A acuidade visual pré-operatória média foi igual a 0,12±0,15 no grupo com coloração por indocianina verde e 0,18±0,18 no grupo sem a coloração pela indocianina verde (p=0,02). A acuidade visual pós-operatória média foi igual a 0,27±0,27 no grupo com uso e 0,43±0,25 no grupo sem uso (p=0,0002). Observamos melhora da acuidade visual em 63% dos casos no grupo com corante e em 80,3% dos casos no grupo sem corante. O fechamento do buraco macular ocorreu em 76,5% dos casos com uso de indocianina verde e em 95,1% dos casos sem utilização do corante. CONCLUSÃO: As cirurgias do buraco macular com remoção da membrana limitante interna sem uso de corantes apresentam melhores resultados visuais e anatômicos quando comparadas àquelas com o auxílio da coloração pela indocianina verde. Recomendamos cautela ao utilizar a coloração com indocianina verde na cirurgia do buraco macular pelo seu possível efeito tóxico. Resumo em inglês PURPOSE: To describe comparatively the outcomes of macular hole surgery followed by internal limiting membrane removal with and without indocyanine green staining. METHODS: We evaluated 142 consecutive macular hole surgeries with internal limiting membrane removal performed in the period from January 2001 to March 2004. These were divided into two groups, based on the use or not of indocyanine green staining. RESULTS: Both studied groups were similar concerning the patien (mais) ts' profile and preoperative stage of the macular holes. Mean preoperative visual acuity was 0.12±0.15 in the group with indocyanine green staining and 0.18±0.18 in the group without internal limiting membrane staining (p=0.02). Mean postoperative visual acuity was 0.27±0.27 in the group with internal limiting membrane staining and 0.43±0.25 in the group without internal limiting membrane staining (p=0.0002). We observed improvement of visual acuity in 63% of cases in the group in which internal limiting membrane staining was performed and in 80.3% of cases in the group without internal limiting membrane staining. Macular hole closure rates were 76.5% in the group treated with internal limiting membrane staining and 95.1% in the group treated without internal limiting membrane staining. CONCLUSIONS: Macular hole surgeries followed by internal limiting membrane removal without use of staining have better visual and anatomic results when compared to macular hole surgeries followed by internal limiting membrane removal guided by indocyanine green staining. We recommend caution in using indocyanine green staining in macular hole surgeries due to its possible toxic effect.
Efeito da técnica de curtimento e do método utilizado para remoção da pele da tilápia-do-nilo sobre as características de resistência do couro/ Effect of tanning technique and methods used for skin removal on leather resistance characteristics of Nile Tilapia
Resumo em português Um estudo foi realizado com o objetivo de avaliar os efeitos do método de remoção da pele do filé (com alicate e com máquina) e da técnica de curtimento (com ou sem sais de cromo, bioleather) sobre a resistência da pele de tilápia-do-nilo (Oreochromis niloticus). Foram retiradas as peles de 40 tilápias (450 g), 20 com uso de alicates e 20 com auxílio de máquina. Após o curtimento e a retirada dos corpos-de-prova, as peles foram encaminhadas a um laboratório a (mais) climatizado (23ºC e 50% de umidade relativa do ar) para realização dos testes de resistência em dinamômetro EMIC, com velocidade de afastamento entre cargas de 100 ± 20 mm/mm. O método de retirada da pele do filé não afetou os resultados dos testes de tração e rasgamento progressivo. A pele retirada com a máquina apresentou elongação superior (88,48%) à removida com alicate (71,09%). Peles curtidas com sais de cromo (25,54 N/mm; 12,18 N/mm²) foram mais resistentes que as curtidas sem sais de cromo (bioleather) (13,11 N/mm; 9,89 N/mm²). Peles curtidas por estas técnicas (com cromo e bioleather) podem ser utilizadas na confecção de vestuários, pois as médias dos testes de tração, alongamento e rasgamento progressivo foram superiores a 9,80 N/mm², 60% e 14,72 N/mm, respectivamente, valores mínimos recomendados para couros curtidos ao cromo. Resumo em inglês This research evaluated the effect of different methods (fillet skin removal and tanning methods [with or without chromium salts and bioleather]) on leather resistance characteristics of Nile Tilapia (Oreochromis niloticus). Skin from 40 tilapias (450 g) were removed: 20 by pliers and 20 by machine. After skin tanning, the samples were removed for resistance tests, which were done, in a climatized environment (23ºC) and 50% air relative humidity, with EMIC dynamometer, a (mais) t removal speed of 100 ± 20 mm/mm. No effect of fillet skin removal method on progressive tearing and strength was observed. The method of skin removal by machine resulted in greater (88.48%) elongation than that removed by pliers (71.09%). Skin tanned with chromium salts (25.54 N/mm; 12.18N/mm²) had higher resistance than that tanned without chromium (bioleather) (13.11 N/mm; 9.89 N/mm²). Chromium- and bioleather tanned skins may be used in clothes manufacture since average values of strength, elongation and progresive tearing are higher than 9.80N/mm², 60% and 14.72 N/mm, respectively, which are values recommended for leathers tanned with chromium salts.
Microesferas de quitosana reticuladas com tripolifosfato utilizadas para remoção da acidez, ferro(III) e manganês(II) de águas contaminadas pela mineração de carvão/ Chitosan microspheres crosslinked with tripolyphosphate used for the removal of the acidity, iron (III) and manganese (II) in water contaminated in coal mining
Resumo em inglês Considerable attention has been paid to chitosan and derivatives as efficient adsorbents of pollutants such as metal ions and dyes in aqueous medium. Nevertheless, no report can be found on the remedial actions of chitosan microspheres crosslinked with tripolyphosphate to control acidity, iron (III) and manganese (II) contents in wastewaters from coal mining. In this work, chitosan microspheres crosslinked with tripolyphosphate were used for the neutralization of acidity (mais) and removal of Fe (III) and Mn (II) from coal mining wastewaters. The study involved static and dinamic methods. The neutralization capacity of the surface of the static system was 395 mmol of H3O+ per kilogram of microspheres, higher than that of the dynamic one (223 mmol kg-1). The removal of Fe(III) in wastewater was of 100% and that of Mn(II) was 90%.
Influência do pH de coagulação e da dose de sulfato de alumínio na remoção de oocistos de Cryptosporidium por filtração direta descendente/ The influence of coagulation pH and aluminum sulphate dose in removal of Cryptosporidium oocysts by down flow direct filtration
Resumo em português No presente trabalho, realizado em escala piloto, foi avaliada a influência do pH de coagulação e a da dose de sulfato de alumínio na morfologia dos flocos formados durante o processo de coagulação bem como na remoção de oocistos de Cryptosporidium por filtração direta descendente. As condições de coagulação testadas incluíram a dose ótima e superdose de coagulante em duas faixas distintas de pH. Os resultados mostraram que a eficiência de remoção dos o (mais) ocistos de Cryptosporidium variou de 1,4 a 3,2 log durante a operação estável do filtro. Os experimentos realizados em valores de pH de coagulação mais baixo, em torno de 5, promoveram as melhores eficiências de remoção de oocistos de Cryptosporidium. A análise morfológica dos flocos mostrou uma tendência à formação de flocos mais porosos e irregulares ao se adotar superdosagem de coagulante. Resumo em inglês This study, carried out in pilot scale, investigates the influence of coagulation pH and aluminum sulphate dosage on the morphology of flocs formed during coagulation and in the removal of Cryptosporidium oocysts by down flow direct filtration. Evaluated coagulation conditions included optimal and over dosages of coagulant in two distinct pH ranges. The results showed that the removal efficiency of Cryptosporidium oocysts ranged from 1.4 to 3.2 log during regular operatio (mais) n of the filter. Experiments carried out with lower coagulation pH values, around 5, presented the best removal efficiencies of Cryptosporidium oocysts. The morphologic analysis of flocs showed a trend to the formation of more porous and irregular flocs with the use of over dosages of coagulant.
Fotocatálise heterogênea com TiO2 para oxidação de arsênio e sua remoção de águas por coprecipitação com sulfato férrico/ Heterogeneous photocatalysis with TiO2 for the oxidation of arsenic and its removal from water by coprecipitation with ferric sulfate
Resumo em inglês The oxidation of arsenic (As(III) to As(V)) in water samples was performed by heterogeneous photocatalysis using a TiO2 film immobilized inside a photochemical reactor. After oxidation, As(V) was removed from the water samples by coprecipitation with ferric sulfate. The final conditions of oxidation and arsenic removal (TiO2 film prepared with a suspension: 10% (w/v); pH: 7.0; oxidation time: 30 min and Fe3+ concentration: 50 mg L-1) were applied in natural water samples (mais) which were supplemented with 1.0 mg L-1 of As(III) to verify the influence of the matrix. After treatment, more than 99% of arsenic was removed from the water.
Resumo em português A eletroquímica e a concentração de matéria orgânica nos horizontes superficiais de Latossolos correlacionam-se estreitamente. No presente trabalho, avaliaram-se as propriedades eletroquímicas do horizonte superficial de sete Latossolos brasileiros após a remoção das substâncias húmicas em meio alcalino. Os solos foram separados em dois grupos, segundo sua mineralogia, caulinítica e oxídica. O extrator NaOH 0,1 mol L-1 solubilizou substâncias húmicas corres (mais) pondentes a menos de 3 % da MO total, indicando forte adsorção específica do material orgânico à fração mineral. A extração de ácidos húmicos e fúlvicos foi capaz de inverter o sinal de carga da superfície; no entanto, o efeito mais acentuado da retirada das substâncias húmicas solúveis foi a perda da capacidade-tampão das cargas do solo. A capacidade da dupla camada elétrica, uma medida indireta desse poder-tampão, aumentou de 3 a 15 vezes depois da extração das substâncias húmicas alcalino-solúveis. Solos com mineralogia predominantemente oxídica apresentaram maiores valores do ponto de efeito salino nulo, da capacidade da dupla camada elétrica, além da diminuição na capacidade de troca de cátions do que aqueles de natureza caulinítica. Resumo em inglês Electrochemistry and organic matter concentrations in the surface horizons of Oxisols are closely related. This study evaluated the electrochemical properties in the surface horizon of seven Brazilian Oxisols after the removal of humic substances by alkaline extraction. Based on their mineralogy the soils were grouped as kaolinitic or oxidic. Less than 3 % of the total organic matter were soluble humic substances extractable by NaOH 0.1 mol L-1, indicating their strong sp (mais) ecific adsorption to the inorganic mineral sites. The removal of the humic and fulvic acids reversed the soil surface charge and also led to a marked loss in the buffering capacity of the soil charge. The electric double layer capacity, an indirect measure of this buffer capacity, increased 3 to 15 times after extracting humic substances. The point of zero salt effect and the electric double layer capacity values were higher and the cation exchange capacity was lower in the oxidic than in the kaolinitic soils.
Resumo em português OBJETIVO: Descrever a técnica da retirada de sutura em córnea clara, evitando-se o contato da parte externa do fio com o meio intra-ocular e avaliar se esse procedimento evitaria infecções. MÉTODOS: Foi realizado estudo retrospectivo de 1.233 casos de retirada de sutura de mononylon 10.0 em córnea clara, utilizando-se laser de argônio para cortar o fio, no qual se avaliou a incidência de infecções. RESULTADOS: Em 1.071 olhos, um tiro foi suficiente para cortar o (mais) ponto. Em 162 olhos, o tiro do laser atingiu a parte epitelial da sutura, sendo necessários disparos extras para cortar a parte intra-estromal e, assim, retirá-la sem que a parte externa do fio passasse pelo interior da córnea. Não ocorreram complicações após a retirada da sutura. CONCLUSÕES: A técnica utilizada mostrou-se eficaz na remoção das suturas e possivelmente apresenta risco menor de infecção, uma vez que a parte do fio sobrejacente ao epitélio não entra em contato com as camadas mais internas da córnea, nem com a câmara anterior, não tendo sido observado nenhum caso de infecção nesta pesquisa. Resumo em inglês PURPOSE: To describe the technique of clear-cornea suture removal, that avoids the contact of the external part of the thread with the intraocular medium, and to evaluate whether this procedure would prevent infections. METHODS: A retrospective study of 1.233 cases of clear-cornea mononylon 10.0 suture removal, by the use of an argon laser to cut the thread, was performed. Incidence of infection was then assessed. RESULTS: In 1.071 eyes, one shot was enough to cut the sti (mais) tch. In 162 eyes, the laser shot hit the epithelial part of the suture, making new shots necessary to cut the intrastromal part, and thus to remove it assuring that the outer part of the stitch would not come in to contact with the interior of the cornea. There were no complications after suture removal. CONCLUSIONS: The technique has shown to be effective in suture removal. And, possibly, presents a lower risk for infection, since the external part of the thread does not come in to contact with the innermost parts of the cornea, or with the anterior chamber. No cases of infection have been observed during this research.
Resumo em inglês In this work the adsorption features of hydrotalcites (Al, Mg- CO3) and the magnetic properties of iron oxides have been combined in a composite to produce a magnetic adsorbent. These magnetic composites can be used as adsorbents for anionic contaminants in water and subsequently removed from the medium by a simple magnetic process. The magnetic hydrotalcites were characterized by XRD, magnetization measurements, N2 adsorption isotherms and Mössbauer spectroscopy. These magnetic adsorbents show remarkable adsorption capacity for anionic contaminants in water.
Resumo em inglês Red mud is the principal residue of the alumina (Al2O3) industry. Generated during the Bayer process, it is characterized by strong alkalinity and ion exchange. Iron oxides are the principal component (30 to 60%). Annually millions of tons of red mud are generated in the world. Red mud disposal is responsible for a large part of the cost of alumina production. On the other hand, textile industry wastewaters containing dyes have a great impact on the environment and on hum (mais) an health. In this paper the possibility of applying red mud for the removal of dyes was investigated by two processes: adsorption and degradation by the Fenton reagent.
Resumo em inglês The tanning process in the leather industry generates very high quantities of chromium-containing solid waste ("wet blue" leather). Environmental concerns and escalating landfill-costs are becoming increasingly serious problems for the leather industry and an alternative disposal is needed. In this work, we are presenting a novel application for this solid waste, which is the removal of organic contaminants from aqueous-solution. The adsorption isotherm of "wet blue" leat (mais) her waste from the AUREA tanning company in Erechim-RS (Brazil) showed that this material presents high adsorption capacities of the reactive textile dyes.
Resumo em inglês Green coconut shells were treated with acid, base and hydrogen peroxide solutions for 3, 6, 12 and 24 h for removing toxic metals from synthetic wastewater. The removal of ions by the adsorbent treated with 0.1 mol L-1 NaOH/ 3h was 99.5% for Pb2+ and 97.9% for Cu2+. The removal of Cd2+, Ni2+, Zn2+, using adsorbent treated with 1.0 mol L-1 NaOH/3 h, was 98.5, 90.3 and 95.4%, respectively. Particle size, adsorbent concentration and adsorption kinetics were also studied. An (mais) adsorbent size of 60-99 mesh and a concentration of 30-40 g/L for 5 min exposure were satisfactory for maximum uptake of Pb2+, Ni2+, Cd2+, Zn2+ and Cu2+ and can be considered as promising parameters for treatment the aqueous effluents contaminated with toxic metals.
Resumo em inglês The solid by-product of the oil shale processing (PETROBRAS - Brazil) was used as raw material to synthesize zeolites A and faujasite. Alkaline fusion followed by hydrothermal treatment was the synthesis procedure used, and five different starting material compositions were obtained. The more crystalline zeolite-type materials synthesized, the pretreated oil shale ash and commercial zeolites were used as adsorbents in the purification of pollutant solutions with arsenic. (mais) The zeolite-type material composed of a mixture of zeolite A (42.6%) and faujasite (52.9%) presented an ion exchange capacity comparable to the pure zeolites A and faujasite, much better than the pretreated ash.
Caracterização de escamas do peixe piau (Leporinus elongatus) e sua aplicação na remoção de Cu(II) de meio aquoso/ Characterization of the piau fish (Leporinus elongatus) scales and their application to remove Cu(II) from aqueous solutions
Resumo em inglês Characterization of fish scales of Leporinus elongatus and their application in the removal of Cu(II) from aqueous solutions are described. It was observed that the scales are mainly formed by hydroxyapatite and type I collagen. Adsorption of Cu(II) was performed using batch experiments at 25 0C. The ANOVA statistical results have shown that the Langmuir model was successful applied to determine the maximum adsorption capacity of 2.686 x10-4 mol g-1 and the Langmuir equil (mais) ibrium parameter (b) of 168.8 L mol-1. The Langmuir separation parameter, R L, has shown favorable adsorption of Cu(II) on the scales.
Síntese e caracterização de nanopartículas de óxido de ferro suportadas em matriz carbonácea: remoção do corante orgânico azul de metileno em água/ Synthesis and characterization of iron oxide nanoparticles supported on carbon matrix: oxidation of the dye methylene blue in water
Resumo em inglês In this work were prepared composites of iron oxide and carbonaceous materials in two different weight proportions (Carbon/Fe 1/1 and 1/2). The physico-chemical properties of the composites were determined by temperature programmed reduction (TPR), adsorption/dessorption of N2, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and pulse titration H2. The XRD and XPS analysis showed a cubic iron oxide phase, identified as maghemite, formed over the carbon sur (mais) face. The particle size of maghemite showed to be within 10-30 nm. Carbon/Fe 1/2 was the most active in MB removal kinetics and ESI-MS studies showed that MB removal by both composites leads to oxidized intermediates.
Resultado funcional e índice macular em portadores de buraco macular submetidos à cirurgia com remoção da membrana limitante interna/ Functional outcome and macular index in macular hole patients who underwent surgery with internal limiting membrane removal
Resumo em português OBJETIVOS: Avaliar o resultado funcional e o índice macular dos portadores de buraco macular submetidos à cirurgia com remoção da membrana limitante interna. MÉTODOS: Quinze olhos de 15 pacientes com buraco macular estágios 2, 3 e 4 foram incluídos no estudo. Todos foram submetidos à cirurgia de buraco macular convencional com remoção da membrana limitante interna corada pelo azul de tripan. Melhor acuidade visual com correção e cortes transversais medidos por (mais) tomografia de coerência óptica (OCT) foram avaliados no pré- e pós-operatório. O índice macular (razão entre a altura e base do buraco macular) foi calculado e correlacionado com o diâmetro mínimo do buraco macular e o ganho de acuidade visual pós-operatória. RESULTADOS: Obteve-se fechamento do buraco macular em todos pacientes operados. Em 86,7%, houve ganho de pelo menos três linhas de visão. O índice macular demonstrou correlação negativa significante com o diâmetro mínimo (r=0,811). Não foi observada correlação significante entre o índice macular e o ganho de acuidade visual pós-operatória (r=0,351). CONCLUSÃO: Os resultados funcionais na cirurgia do buraco macular com remoção da membrana limitante interna foram bons neste grupo de pacientes. O índice macular demonstrou ser compatível com a configuração espacial do buraco macular, porém não foi preditor de resultados visuais. Resumo em inglês PURPOSE: To evaluate the functional outcome and macular index in patients with macular hole who underwent surgery with internal limiting membrane removal. METHODS: Fifteen eyes of 15 patients with idiopathic macular hole stages 2, 3 or 4 were enrolled in this study. All patients underwent conventional macular hole surgery with trypan blue staining to remove the internal limiting membrane. The best-corrected visual acuity and cross-sectional images of macular hole measured (mais) by optical coherence tomography (OCT) were evaluated pre- and postoperatively. The macular hole index (ratio of hole height to base diameter of the hole) was calculated and correlated with minimum diameter of the macular hole and postoperative gain in visual acuity. RESULTS: Macular hole closure was observed in all operated patients. In 86.7%, there was a visual gain of at least three lines. Macular hole index was significantly negative correlated with the minimum diameter of the macular hole (r=0.811). There was no significant correlation between macular index and postoperative gain in visual acuity (r=0.351). CONCLUSION: Functional outcomes with internal limiting membrane removal were good in this group of patients. Macular index was compatible with spatial configuration of the macular hole, however visual outcomes were not predictable.
Comparação entre os resultados da descompressão orbitária antro-etmoidal isolada e associada à remoção de tecido adiposo/ A comparative study between the results of antro-ethmoidal orbital decompression isolated and associated with orbital fat removal
Resumo em português OBJETIVO: Comparar os resultados da descompressão orbitária antro-etmoidal isolada àqueles da mesma cirurgia associada à remoção de tecido orbitário em paciente com orbitopatia distiroidiana seqüelar. MÉTODOS: Foram analisadas 2 modalidades de descompressão orbitária. Ambas tiveram como indicação apenas a correção estética e do desconforto ocular dos pacientes. Todos pacientes se apresentavam na fase inativa da orbitopatia distiroidiana. Em um grupo de 12 (mais) pacientes (grupo 2) foram realizadas 19 cirurgias de descompressão orbitária antro-etmoidal isolada. No outro grupo (grupo 1) composto por 8 pacientes foram realizadas 10 cirurgias de descompressão óssea antro-etmoidal associada à remoção de aproximadamente 1 centímetro cúbico de tecido adiposo da órbita. Os resultados das cirurgias nos dois grupos foram comparados entre si. RESULTADOS: No grupo 2 a redução da proptose oscilou entre 1 e 5 mm (média 3,68±1,10 mm) e no grupo 1 variou de 1 a 5 mm (média 3,25±1,36 mm). CONCLUSÕES: Tanto a descompressão óssea isolada como aquela associada à remoção de tecido adiposo orbitário apresentam redução semelhante na proptose, não havendo diferença significativa entre elas. A remoção de gordura temporal inferior, em torno de 1 centímetro cúbico parece não aumentar a redução da proptose quando comparada com a cirurgia descompressiva óssea isolada. Porém fatores como a complacência de tecidos moles, a quantidade de gordura retirada e as janelas ósseas realizadas em cada grupo devem ser considerados na conclusão deste trabalho retrospectivo de comparação entre técnicas. Resumo em inglês PURPOSE: To compare the results of isolated antral-ethmoidal orbital decompression and that associated with orbital fat removal in patients with dysthyroid orbitopathy. METHODS: Nineteen isolated antral-ethmoidal orbital decompressions were performed in a group of 12 patients (19 orbits) with the diagnosis of dysthyroid ophthalmopathy in the quiescent stage. The same procedure, but in association with orbital fat removal, were performed in another group of 8 patients (10 (mais) orbits) also with the diagnosis of dysthyroid ophthalmopathy in the quiescent stage. The results of both groups were compared. RESULTS: In the first group the amount of retroplacement of the globe achieved 1-5 mm (mean 3.68±1.10 mm) and in the second group it achieved 1-5 mm (mean 3.25±1.36 mm). CONCLUSIONS: There was no significant difference between the results of the isolated antral-ethmoidal orbital decompression and that associated with orbital fat removal. The removal of 1ml of seems not to improve the retroplacement of the globe as an association with a 2-wall orbital decompression. However, many conditions must be considered to conclude any comparison between the two orbital decompression techniques, such as orbital soft tissue compliance, amount of fat removal and size of bone opening.
Resumo em inglês In this work the adsorption features of zeolites (NaY, Beta, Mordenite and ZSM-5) have been combined with the magnetic properties of iron oxides in a composite to produce a magnetic adsorbent. These magnetic composites can be used as adsorbents for contaminants in water and subsequently removed from the medium by a simple magnetic process. The magnetic zeolites were characterized by XRD, magnetization measurements, chemical analyses, N2 adsorption isotherms and Mössbauer (mais) spectroscopy. These magnetic adsorbents show remarkable adsorption capacity for metal ion contaminants in water.
A relevante potencialidade dos centros básicos nitrogenados disponíveis em polímeros inorgânicos e biopolímeros na remoção catiônica/ The weighty potentiality of nitrogenated basic centers in inorganic polymers and biopolymers for cation removal
Resumo em inglês This review reports the application of inorganic and organic polymeric materials for cation removal by using nitrogenated basic centers. The data demonstrate the importance of the desired groups when free or immobilized on natural or synthesized inorganic polymers through silanol groups. Thus, the most studied silica gel is followed by natural crysotile and talc polymers, and the synthesized mesopore silicas, talc-like, silicic acids, phosphates and phyllosilicates. The o (mais) rganic natural biopolymeric chitin and cellulose were chemically modified to improve the availability of the amine groups or the reactivity with desirable molecules to enlarge the content of basic centers. The cation removal takes place at the solid/liquid interface and some interactive effects have their thermodynamic data determined.
Resumo em português Neste trabalho estudou-se a aplicabilidade do processo foto-Fenton utilizando irradiação solar no tratamento de dois efluentes (A e B) de uma indústria de tintas. Foi avaliada a influência da concentração inicial de peróxido de hidrogênio e ferro na remoção de carbono orgânico dissolvido (COD). Nos primeiros minutos de irradiação foi observada a descoloração e a remoção de odores. Para o efluente A, atingiu-se 75 % de remoção de COD durante 60 minutos d (mais) e irradiação. Para o efluente B, adições múltiplas de peróxido de hidrogênio foram necessárias para aumentar a remoção de COD, 43 % em 60 minutos de irradiação. Os resultados obtidos mostram que o processo foto-Fenton solar pode ser aplicado ao tratamento dos efluentes gerados na indústria de tintas. Resumo em inglês The photo- Fenton process was evaluated for the treatment of two effluents (A and B) from ink industry. The influence of hydrogen peroxide and iron (II) concentration on the dissolved organic carbon (DOC) removal was evaluated. In the first minutes of irradiation the color and odors were removed. For the effluent A 75% of DOC removal was reached in 60 min irradiation. For the effluent B, multiple additions of H2O2 were necessary to improve the COD removal, reaching 43% of (mais) TOC in 60 min irradiation. The results obtained demonstrate that the solar photo-Fenton process can be applied for the treatment of effluents generated by ink industry.
Resumo em português Os astrocitomas e oligodendrogliomas supratentoriais dos adultos são tumores infrequentes. Analisamos retrospectivamente 23 pacientes com este tipo de neoplasia que foram operados entre 1986 e 2002. Não ocorreu nenhum óbito no pós-operatório. A sobrevida de 5 e 10 anos de todo o grupo foi 67 e 30% respectivamente, semelhante a outras experiências. Em 14 pacientes obtivemos a remoção completa da lesão (60,8%) e em 9 (39,2%) ocorreu remoção parcial do tumor. No s (mais) ubgrupo da ressecção total do tumor, 89% sobreviveram 5 anos e 45% alcançaram 10 anos de sobrevida, em contraste com o subgrupo da remoção parcial em que somente 35% alcançaram os 5 anos de sobrevida e nenhum, 10 anos. Devido aos efeitos deletérios da radioterapia, nós preferimos prescrevê-la apenas nos casos de recorrência tumoral. Resumo em inglês Low-grade supratentorial astrocytomas and oligodendrogliomas in adults are uncommon tumors of the central nervous system. We analyzed retrospectively 23 patients with this type of neoplasia, who were operated on between 1986 and 2002. There were no post-operative deaths. The survival rate at 5 and 10 years post-surgery for the entire sample was 67 and 30% respectively, similar to other outcomes. With 14 patients we achieved a complete removal of the lesion (60.8%) and wit (mais) h 9 (39.2%) partial removal of the tumor. In the sub-group which underwent total resection of the tumor, 89% survived 5 years and 45% attained 10 years of survival, in contrast with the sub-group that underwent partial removal in which only 35% attained 5 years of survival and none 10 years. Due to the deleterious effects of radiation therapy, we preferred to prescribe it only in cases of tumor recurrence.
Resumo em português O relato mostra um caso de oftalmomiíase pós-traumática em um paciente etilista crônico, com fratura orbitozigomática, descrevendo a importância do tratamento precoce e a necessidade de associar Ivermectina à remoção cirúrgica das larvas. Resumo em inglês The report shows a case of post-traumatic ophthalmomyiasis in a chronic alcoholic patient with orbitozygomatic fracture, it describes the importance of early treatment and the association of Ivermectin and surgical removal of larvae.
Resumo em português OBJETIVO: Avaliar a eficácia e possíveis complicações da remoção do segmento vertical do canalículo lacrimal, em pacientes com síndrome do olho seco grave. MÉTODOS: Seis canalículos de quatro pacientes, 3 dos quais tinham o diagnóstico de olho seco associado à síndrome de Sjögren primária e o quarto, ceratoconjuntivite sicca por remoção completa de glândula lacrimal, foram submetidos a exérese do segmento vertical do canalículo lacrimal. Os critérios (mais) de inclusão foram: sinais e sintomas de olho seco que não melhoraram com tratamento clínico, Schirmer menor que 5 mm, rosa bengala corando córnea e conjuntiva e casos de recanalização após eletrocauterização dos pontos. Os pontos lacrimais foram avaliados por exame biomicroscópico após 7, 15, 30, 90 e 180 dias da cirurgia. RESULTADOS: No período de seguimento, nenhum canalículo sofreu recanalização. Em cinco olhos, houve diminuição da ceratite ponteada difusa e dos filamentos corneanos e melhora nos valores do teste de Schirmer e rosa bengala. No olho submetido à remoção completa da glândula lacrimal, a córnea ainda apresentava ceratite ponteada difusa, mesmo após dois meses de cirurgia. Não houve alterações da margem palpebral. CONCLUSÃO: Esta técnica, além de mostrar-se efetiva e simples para oclusão permanente do canalículo lacrimal, não cursou com complicações observadas em outros procedimentos. Resumo em inglês PURPOSE: To demonstrate the efficacy and possible complications of a surgical technique that includes the removal of the vertical portion of the lacrimal canaliculus in patients with dry eye syndrome. METHODS: A study was performed on six canaliculi of six eyes (four patients). Three patients had dry eye, associated with primary Sjögren syndrome. One of the four patients developed keratoconjuntivitis sicca due to lacrimal gland removal. The criteria included: patients wi (mais) th symptoms of dry eye that did not improve even with the continuous use of artificial tears, low results (less than 5 mm) with the Schirmer test, rose bengal staining and cases of recanalization after thermal occlusion with electrocauterium. The lacrimal puncta were examined after 7, 15, 30, 60, 90 and 180 days after surgery. RESULTS: None of the canaliculus recanalized at this time. Punctate keratitis, corneal filaments, Schirmer and rose bengal tests improved in 5 eyes. Difuse punctate keratitis was present in the patient with lacrimal gland removal even 2 months after of surgery. Eyelid margin complications were not observed. CONCLUSION: This technique is simple and effective in permanent lacrimal canaliculus occlusion. We did not note any complications compared to other procedures.
Aplicação de material zeolítico sintetizado de cinzas de carvão como adsorvente de poluentes em água/ Application of zeolitic material synthesized from coal ashes as adsorbent for pollutants from water
Resumo em português Cinzas leve de carvão tratadas pelo método hidrotérmico foram usadas como adsorvente de baixo custo para a remoção de íons metálicos e corante de solução aquosa. As isotermas de adsorção das cinzas leve tratadas foram estudadas e os resultados foram ajustados pelos modelos de Langmuir e Freundlich. A isoterma de Freundlich descreveu melhor o processo de adsorção do azul de metileno. Os dados de equilíbrio para a adsorção dos íons zinco e cádmio se ajusta (mais) ram melhor á equação de Langmuir. O valor máximo de capacidade de adsorção obtido foi de 0,78 (mg g-1)(L mg)1/n para o azul de metileno, 38,1 mg g-1 para o Zn2+ e 67, 5 mg g-1 para o Cd2+. Os materiais sintetizados exibiram capacidades de adsorção muito maiores do que as das cinzas leves usadas como matéria-prima. O estudo mostrou que o material zeólitico pode efetivamente adsorver azul de metileno e íons metálicos com eficiências de remoção na faixa de 82-99%. Resumo em inglês Coal fly ashes treated by hydrothermal method were used as low-cost adsorbent for the removal of metals ions and dye from aqueous solution. The adsorption isotherms of the treated fly ashes were studied and results were fitted using Langmuir and Freundlich models. It shows that the Freundlich isotherm is better in describing the adsorption process for methylene blue. The equilibrium data for zinc and cadmium ions adsorption well fitted to the Langmuir equation. The maximu (mais) m adsorption capacity value obtained was 0.78 (mg g-1)(L mg)1/n for methylene blue, 38.05 mg g-1 for Zn2+ and 67.48 mg g-1 for Cd2+. The synthesized materials exhibit much higher adsorption capacities than raw fly ashes. The study showed that the zeolitic material can effectively adsorb methylene blue and metals ions with removal efficiencies ranging from 82-99%.
Efeito da desfolha de ramos sobre a indução de brotos e flores em atemóia (Anonna cherimola Mill x Anonna squamosa L.)/ Effects of leaf removal of atemoya branches (Anonna cherimola Mill x Anonna squamosa L.) on shoot and flower formation
Resumo em português Avaliou-se o efeito do desfolhamento de ramos na produção de brotos e flores em plantas adultas de atemóia (Anonna cherimola Mill x Anonna squamosa L.) var. Gefner. O experimento foi realizado em plantio comercial no município de Maceió - AL. Foram utilizadas 24 plantas podadas com altura de 1.5 m e espaçadas de 4 x 2 m. Os ramos maduros tiveram seus ápices removidos na altura da 4ª folha, sendo depois submetidos aos seguintes tratamentos de desfolha manual: 1) de (mais) sfolha total dos ramos; 2) remoção das cinco primeiras folhas dos ramos a partir dos ápices podados; 3) remoção de cinco folhas compreendidas entre 6ª a 10ª gemas dos ramos; 4) controle = sem desfolha dos ramos. Os resultados coletados 30 dias após a desfolha mostraram que o número de brotações nos tratamentos com desfolha total e desfolha das cinco gemas superiores foi estatisticamente superior aos tratamentos sem desfolha e desfolha da 6ª à 10ª gema. O tratamento com desfolha das cinco gemas superiores apresentou o maior número de ramos florados (61%). Resumo em inglês The effects of leaf removal from selected sections of atemoya branches var. Gefner on shoot and flower formation were evaluated. The experiment was carried out in a commercial orchard in Maceió, State of Alagoas, Brazil. Twenty four adult plants pruned to 1.5 m height with a 4 x 2 m spacing were used. All mature lignified branches had their tip pruned up to the 4th leaf. After pruning the following treatments were applied: 1) total leaf removal from the branches; 2) remo (mais) val of the first five leaves counted from the pruned tip; 3) removal of the five leaves between the 6th and 10th buds of the branches; 4) Control = no leaf removal. The results obtained at 30 days after leaf removal showed that the number of new shoots was statistically superior in the treatments with total leaf removal and removal of the first five leaves in relation to the two other treatments studied. The treatment with the removal of the first five leaves presented the highest number of branches with flowers (61%).
Resumo em português Avaliou-se neste estudo a eficiência de sistemas compostos de duas espécies de macrófitas aquáticas flutuantes (Eichhornia crassipes e Pistia stratiotes) no tratamento de efluentes gerados por um viveiro de manutenção de reprodutores de camarões-canela (Macrobrachium amazonicum). Os sistemas de tratamento foram constituídos de 12 unidades experimentais com as macrófitas aquáticas e três sem plantas (controle). Foram analisadas amostras da água de abastecimento (mais) do viveiro de criação de camarões-d'água-doce, do efluente gerado e dos efluentes tratados. A remoção de nutrientes não diferiu significativamente entre as duas espécies vegetais. As maiores remoções foram obtidas para fósforo total (41,9% pelo controle; 71,6% por E. crassipes; 69,9% por P. stratiotes; 72,5% por E. crassipes + P. stratiotes e 72,1% por P. stratiotes + E. crassipes) e para turbidez (30,6% pelo controle; 80,2% por E. crassipes; 75,2% por P. stratiotes; 79,8% por E. crassipes + P. stratiotes e 81,5% por P. stratiotes + E. crassipes). As macrófitas aquáticas foram eficientes na remoção de nitrogênio e fósforo dos efluentes de criação de M. amazonicum. Resumo em inglês The efficiency of systems composed of two species of floating aquatic macrophyte (Eichhornia crassipes and Pistia stratiotes) to treat effluents from shrimp culture was evaluated in this research. The effluent originated from a pond populated with Macrobrachium amazonicum. Treatment systems consisted of 12 experimental tanks with aquatic macrophyte and three tanks without plants (control). Water samples were collected from the fresh water supply and before and after passi (mais) ng through the treatment systems. There are no differences in the removal of nutrients between the two species. The higher nutrient removal was observed for total phosphorus (41.9% by control; 71.6% by E. crassipes; 69.9 by P. stratiotes; 72.5% by E. crassipes + P. stratiotes and 72.1 by P. stratiotes + E. crassipes) and turbidity (30.6% by control; 80.2% by E. crassipes; 75.2 by P. stratiotes; 79.8% by E. crassipes + P. stratiotes and 81.5 by P. stratiotes + E. crassipes). The systems containing aquatic macrophytes were efficient in nitrogen and phosphorus removal from M. amazonicum culture.
Viscoelásticos oftálmicos: comparação entre os comerciais e formulações de galactomanana de Dimorphandra gardneriana/ Ophtalmic viscosurgical devices: comparison between commercial and formulations based on Dimorphandra gardneriana galactomannan
Resumo em inglês Ophthalmic viscosurgical devices (OVD) are materials injected in intraocular space during cataract removal to reduce trauma in the patient's eye. Three Brazilian commercially available OVDs (Medilon®, Metilcelulose® and Ofthyal®) were evaluated as well as formulations based on Dimorphandra gardneriana galactomannan. Viscosity and viscoelastic parameters, such as viscosity at zero shear, pseudoplasticity index, elastic and viscous moduli, relaxation time, were determine (mais) d and compared. Characteristics of an effective OVD were proposed. None of the Brazilian devices studied fulfill the rheological requirements. Only the galactomannan at 3% concentration showed potential to be used as effective OVD.
Resumo em inglês Coal ashes produced in coal-fired power plant could be converted into zeolites and can be used as low-cost adsorbents for the treatment of effluents contaminated with high levels of toxic metals. The capacity of synthetic zeolites for the removal of cadmium, zinc and copper ions from aqueous solutions has been investigated under different operating conditions. Zeolite from bottom chimney showed higher removal efficiency for metals ions than zeolite from feed hopper and mi (mais) xing mill. The results indicated that the treated bottom ash could be applied in environmental technology as an immobilizer of pollutants.
Resumo em inglês This work describes the results of the purification of methyl biodiesel, obtained by oxidized soybean oil, using different methods. After the ester separation from the glycerin by decanting, the ester was purified each time with distillation, washing with water and adsorption with bauxite, bentonite and attapulgite. The removal of total contamination, unsaponifiable material, concentrations of free glycerin and soap were analyzed in the purified ester phase. The best resu (mais) lt of purification was observed with the use of bentonite and bauxite, in the removal of soap and free glycerin respectively.
Uso da cinza da casca do arroz (CCA) obtida da geração de energia térmica como adsorvente de Zn(II) em soluções aquosas/ Use of rice husk ash (RHA) obtained from thermal energy generation as Zn (II) adsorbent in aqueous solutions
Resumo em inglês The removal study was conducted using 1.00 g of the rice husk ash (RHA) and 20.0 mL solution with concentrations in the range of 10-1000 mg/L of Zn(II). The influence of contact time, initial metal concentration, agitation and pH of the removal process was investigated. Superior removals to 95% were obtained at the end of 24 h of contact. The agitation increased in 20% the removal of Zn(II), being needed only 5 min to reach the equilibrium. The adsorption process was stud (mais) ied by the models of isotherms of Langmuir, Freundlich and BET, obtaining results of R L and 1/n for a process favorable of adsorption. BET isotherm best represents the equilibrium adsorption. The results showed that the RHA has the largest capacity and affinity for the removal of Zn(II).
Resumo em inglês Hydrogen peroxide and chlorine are compared as possible disinfectants for water-cooling circuits. To this purpose, samples taken from the cooling system of a steel making plant were treated (at 25ºC and pH values of 5.5 and 8.5) with varying amounts of the two oxidizing agents (0.0 mg/L, 2.0 mg/L and 6.0 mg/L). The results were evaluated through bacterial counting and measurement of corrosion rates upon AISI1020 carbon steel coupons. Bacterial removal and corrosion effects proved to be similar and satisfactory for both reagents.
Resumo em inglês Electroflotation (EF) with aluminum electrodes was applied in the treatment of Brazilian industrial coconut wastewater. The results show that EF with polarity inversion is a very good treatment when compared to others. The removal of pollutants in the wastewater after EF with polarity inversion was 96.3% of oils and grease, 99% of color and 66% of total organic carbon. Also, metal concentrations, turbidity and total solids were reduced.
Tratamento de banhos de tingimento têxtil por processos foto-Fenton e avaliação da potencialidade de reuso/ Treatment of textile dyeing baths by photo-Fenton processes and evaluation of the reuse potentiality
Resumo em inglês In this work the treatment of textile dyeing baths by a sequential reductive-oxidative process was evaluated, aiming its utilization in new dyeing process. The results demonstrated that reactive dyes can be easily degraded by reductive processes mediated by zero-valent iron, a fact that induces decolorizations of about 80%. Sequential photo-Fenton processes permit almost total removal of the residual color with elimination of 90% of the COD content. The reuse of treated r (mais) esidues permits the achievement of materials that attend practically all textile specifications, with exception of the color difference parameter (ΔE), which is unsatisfactory toward the importation standards, but adequate for the national market.
Síntese de poliestireno sulfonado para aplicações no tratamento de água produzido a partir de copos e bandejas descartadas de poliestireno/ Synthesis of poly(styrene sulfonate) from discarded polystyrene cups and expanded trays for application on water treatment
Resumo em inglês In the present paper, the use of poly(styrene sulfonate) (PSS), produced from discarded polystyrene materials through heterogeneous and homogeneous processes, was investigated. The use of PSS for water treatment, using a kaolin suspension as wastewater model, reduced water turbidity for all the employed materials when compared to the blank analysis, without PSS. The most efficient polyelectrolyte was PSS cups obtained by homogeneous route. The same behavior was observed f (mais) or real system. The homogeneous PSS cups showed a balance between a moderate molecular weight and high anionic character that improved flocks formation and water removal turbidity.
Resumo em português O feijão é cultivado e consumido mundialmente e é a leguminosa mais consumida na América Latina. O baixo valor biológico das proteínas do feijão pode ser resultante, dentre outros, da presença de fatores antinutricionais presentes no tegumento do grão. Este trabalho visou avaliar, através de ensaios biológicos, o efeito da retirada do tegumento e das antocianinas e outros polifenóis do feijão-preto, na qualidade de suas proteínas. Foram analisados o quocient (mais) e de eficiência protéica, o quociente de eficiência líquida protéica e a utilização líquida da proteína, e digestibilidade. Os resultados obtidos mostraram que a eliminação parcial do tegumento dos grãos cozidos e secagem em estufa diminuíram significativamente o valor do quociente de eficiência protéica comparativamente ao do grão integral cozido e secado nas mesmas condições. A extração, com etanol acidificado, de 27,5% dos polifenóis não influiu significativamente no valor protéico do feijão-preto. Concluiu-se que a retirada do tegumento e a extração parcial de polifenóis do feijão não elevaram a sua qualidade protéica. Resumo em inglês Bean seeds (Phaseolus vulgaris, L.) are cultivated and consumed all over the world and are a staple food in most countries of South America. The low biological value of bean proteins may be due to, among others, the effect of antinutritional factors on the tegument. The objective of this work was to evaluate, through biological assays, the effect of removal of black bean tegument, anthocyanins and other polyphenols on protein quality. The protein efficiency ratio, the pro (mais) tein liquid efficiency ratio, the protein liquid utilization and the digestibility were analyzed. The results indicated that removal of the tegument of cooked beans reduced their protein value (PER) when compared to whole cooked beans. The ethanolic extraction of 27.5% of polyphenols did not increase the protein quality of beans. It was concluded that removal of the tegument and polyphenols of beans did not improve their protein quality.
Repercussões na auto-estima provocadas pela tricotomia em craniotomia/ Hair removal repercussions on patient's self-esteem in craniotomy/ Repercusiones en la auto estima provocadas por la tricotomía en craneotomía
Resumo em português O objetivo do estudo foi avaliar a repercussão da tricotomia na autoestima do paciente no pós-operatório de craniotomia. Estudo quantitativo do tipo prospectivo. Os dados mostram que a maioria dos pacientes referiu não ter sua autoestima alterada em função da tricotomia; predomina a manutenção da autoestima entre os pacientes que receberam orientação sobre a tricotomia; a maioria fez uso de acessórios como estratégia para ocultar a área raspada, e acredita qu (mais) e a tricotomia não prejudica a qualidade de vida nem interfere nas relações sociais. Conclui-se que os sentimentos relacionados à diminuição da autoestima são a perda da atração, a insegurança e a vergonha; há a necessidade de uso de acessórios para melhorar a auto-imagem, e os profissionais da saúde devem trabalhar com os aspectos psicossociais dos pacientes no pré e pós-operatórios. Resumo em espanhol El objetivo del estudio fue evaluar la repercusión de la tricotomía en la auto estima del paciente en el posoperatorio de craneotomía. Estudio cuantitativo del tipo prospectivo. Los datos muestran que la mayoría de los pacientes refirió no tener su auto estima alterada en función de la tricotomía; predomina el mantenimiento de la auto estima entre los pacientes que recibieron orientación sobre la tricotomía; la mayoría hizo uso de accesorios como estrategia para (mais) ocultar el área raspada y piensa que la tricotomía no perjudica la calidad de vida y no interfiere en las relaciones sociales. Se concluye que los sentimientos relacionados a la disminución de la auto estima son la pérdida de la atracción, la inseguridad y la vergüenza; hay necesidad de usar de accesorios para mejorar la auto imagen y los profesionales de la salud deben trabajar con los aspectos psicosociales de los pacientes en el pre y pos operatorio. Resumo em inglês This quantitative-based, prospective-oriented study aims to evaluate the repercussion of hair removal in post-craniotomy's patient self-esteem. Data show that the majority of patients mentioned not having an altered self-esteem due to hair removal; self-esteem was kept the same among patients that were instructed about the hair removal process. The major part of patients made use of accessories as a strategy to hide shaved areas and believed that hair removal damaged neit (mais) her their quality of life nor their social relationships. We conclude that the feelings directly related to the decrease of self-esteem are loss of physical attraction, insecurity and shame. The employment of accessories is made necessary towards improving self-esteem, and healthcare professionals must work with the psychosocial aspects of pre and post-surgery patients.
Specific marine macro algae species abundant at the Portuguese coast (Laminaria hiperborea, Bifurcaria bifurcata, Sargassum muticum and Fucus spiralis) were shown to be effective for removing toxic metals (Cd(II), Zn(II) and Pb(II)) from aqueous solutions. The initial metal concentrations in solutio...
Resumo em inglês This work studied the pretreatment of sugarcane molasses (CM) and corn steep liquor (CS) for the production of carotenoids by Sporidiobolus salmonicolor (CBS 2636). The acid pretreatment removed less micronutrients than that with activated carbon and led to high removals of Cu and Mn. Reduction in optical density of the prepared medium and removal of glucose from it were 22% and 7% for CM and 95% and 38% for CS, respectively. Total carotenoids obtained with substrates pre (mais) treated with acids (541 mg/L) were higher than the results obtained when the medium was treated with activated carbon (208 mg/L).
Resumo em inglês The black, green and sour coffee defect (PVA) contributes with 20% of the total coffee production. It should be separate from the normal coffee grains in order to improve the final quality of the beverage. In this way, the present work has the objective to use the PVA reject for the production of activated carbon. The activated carbon (CA) was prepared from PVA defect using zinc chloride as activating agent. The prepared material (CA PVA) was characterized and the adsorpt (mais) ion tests were carried out using as organic models methylene blue (AM) and reactive red (VR). The CA PVA revealed to be more efficient in the removal of the organic contaminants compared to a commercial activated carbon.
Resumo em inglês In an effort to minimize the impact on the environment, removal of pollutants, such as phenolic compounds, from the industrial wastewater has great importance nowadays because of the high toxicity and low biodegradability of these compounds. This work discusses the different methods to remove these compounds from industrial wastewater, showing their advantages and disadvantages. Advanced Oxidation Process (AOPs) are presented as a promising technology for the treatment of (mais) wastewater containing phenolic compounds. Among the AOPs, photolysis, photocatalysis and the processes based on hydrogen peroxide and on ozone are discussed with emphasis on the combined processes and the oxidation mechanisms.
Resumo em inglês This work presents two recycling processes for spent Li/MnO2 batteries. After removal of the solvent under vacuum the cathode + anode + electrolyte was submitted to one of the following procedures: (a) it was calcined (500 ºC, 5 h) and the calcined solid was submitted to solvent extraction with water in order to recover lithium salts. The residual solid was treated with sulfuric acid containing hydrogen peroxide. Manganese was recovered as sulfate; (b) the solid was trea (mais) ted with potassium hydrogeno sulfate (500 ºC, 5 h). The solid was dissolved in water and the resulting solution was added dropwise to sodium hydroxide. Manganese was recovered as dioxide. The residual solution was treated with potassium fluoride in order to precipitate lithium fluoride.
Resumo em inglês The main goal of this research was the preparation and use of a organophilic smectitic clay able to promoting the adsorption of phenol. In this work was used a natural clay called Chocolate, from Campina Grande - PB (Brazil). The natural clay was treated with a solution of sodium carbonate. After this the sodium clay was treated with quaternary ammonium salt. The adsorptive study was conducted by different values of pH and temperature. The results showed a better performance in adsorptive at pH 7 and temperature 30 ºC, with removal of more than 80% of phenol.
Resumo em inglês Coffee fruit processing is one of the most polluting activities in agriculture due to the large amount of waste generated in the process. In this work, coffee parchment was employed as precursor for the production of carbons activated with ZnCl2 (CAP). The material was characterized using N2 adsorption/desorption at 77 K, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The material showed a surface area of 521.6 m²g-1 and microporou (mais) s structure. CAP was applied as adsorbent for the removal of methylene blue dye in aqueous medium. The adsorption capacity was found to be about 188.7 mg g-1.
Preparação de membranas de acetato de celulose organomodificadas para adsorção dos íons Cu(II), Cd(II), Mn(II) e Ni(II)/ Preparation of the orgamomodified cellulose acetate membranes for adsorption of the ions Cu(II), Cd(II), Mn(II) AND Ni(II)
Resumo em inglês 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 te (mais) sts 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.
Resumo em português OBJETIVO: Investigar se os transplantes de fígado realizados em um hospital universitário do Ceará eram custos-efetivos. MÉTODOS: Foram avaliados os prontuários dos 62 pacientes transplantados hepáticos em 2007, do dia da internação para o transplante até a data da alta hospitalar ou óbito. Foram determinados indicadores como o número de dias e local de internação, a quantidade de material e medicamentos utilizados, os exames complementares e os procedimentos (mais) realizados. RESULTADOS: A maioria da população era do sexo masculino, procedente do Nordeste e com idade média de 45 anos. O custo médio do transplante hepático foi de US$ 20.605,01. O item que onerou predominantemente o custo foi o repasse para equipe profissional envolvida na captação e transplante; seguido pelas diárias, medicamentos da cirurgia e internamento; e produtos (materiais e medicamentos) utilizados na captação. Quanto ao repasse do SUS, o HUWC recebeu US$1.322,97 para a captação, US$ 3.223,56 para os honorários médicos e US$ 32.235,68 pelo pacote do transplante hepático que inclui do procedimento cirúrgico até o sétimo dia de internamento. CONCLUSÃO: Os valores encontrados foram semelhantes aos determinados por outros centros transplantadores brasileiros. O transplante hepático no Ceará é um procedimento economicamente viável tomando como base o repasse financeiro do SUS. Resumo em inglês OBJECTIVE: To investigate if liver transplants were cost effective at a University Hospital of Ceará. METHODS: We evaluated data from the medical records of 62 liver transplant patients performed in 2007, from the day of admission for the transplant to the date of discharge or death. Indicators such as length of hospital stay and location ,quantity of medical material and medication used, as well as the investigations and procedures performed were determined. RESULTS: Th (mais) e population was mostly male from the Northeast of Brazil with an mean age of 45 years. The mean total cost of a liver transplant was US$20,605.01. The largest part was payment for the professional team involved in the liver removal and transplant, followed by hospital stay , medication used during surgery and hospitalization, and products (medication and materials) used in the liver removal. According to the current schedule, the SUS made the following payments to HUWC; US$1,322.97 for liver removal, US$3,223.56 for medical fees and US$32,235.68 for the package including the complete surgical procedure, hospital expenses and care up to the seventh day of hospitalization. CONCLUSION: Results were similar to those found by other Brazilian transplant centers. Liver transplantation in Ceará is an economically viable procedure based upon the financial transfer from SUS.
Resumo em inglês Many industrial processes produce effluents with a wide variety of xenobiotic organic pollutants, which cannot be efficiently degraded by conventional biological treatments. Thus, the development of new technologies to eliminate these refractory compounds in water has become very imperative in order to assure the quality of this important resource. Ozonation is a very promising process for the treatment of wastewaters containing non-easily removable organic compounds. The (mais) present work aims at highlighting new methods of enhancing the efficiency of ozone towards the removal organic pollutants in aqueous solution. Special attention is given to catalytic ozonation processes contemplating homo- and heterogeneous catalysis, their activity and mechanisms. Recent results and future prospects about the application of these processes to real effluents are also evaluated.
Resumo em português Relatamos nossa experiência com 11 pacientes portadores de meningiomas do forame magno, oito cranioespinhais e três espinocraniais. A média de idade foi 50,8 anos, o sintoma mais comum foi cefaléia occipital com duração média de 18,6 meses. Os principais achados neurológicos foram tetraparesia e comprometimento dos nervos cranianos baixos. O tratamento foi cirúrgico, sempre com exposição da artéria vertebral em sua entrada na dura-máter da fossa posterior e r (mais) essecção de parte do côndilo occipital apenas em três casos. Ressecção total foi possível em sete pacientes e parcial nos demais, devido às aderências a vasos e nervos. O prognóstico esteve relacionado com as condições neurológicas pré-operatórias. Resumo em inglês We report our experience with 11 cases of foramen magnum meningiomas, eight originating inside the posterior fossa and three in the caudal region. The mean age of the patients was 50.8 years and the main complaint was cervical headache for at least 18.6 months and at the neurological examination, tetraparesis and deficit of the lower cranial nerves were very often observed. All patients were submitted to surgical treatment, always with exposition of the vertebral artery a (mais) t the entry zone in the duramater of the posterior fossa, with partial removal of the occipital condyle in only three cases. Total resection was obtained in seven patients and partial removal in the other four due to adherences to vessels and nerves. The prognostic was related to the neurological condition before surgery.
Resumo em inglês This study presents the bactericidal activity of titanium dioxide photocatalysis, using as model Escherichia coli and Pseudomonas sp. cells. It was observed that the process efficiency is related to initial cell concentration, light intensity, UV irradiation exposure time, TiO2 concentration increase. The ultimate removal efficiency was above 99.9%.
Resumo em português Relatamos caso incomum de um paciente de 37 anos com hematoma extradural traumático do vértex com sintomas de hipertensão intracraniana. O diagnóstico foi feito através da tomografia do crânio em cortes coronais e o paciente foi submetido a craniotomia com drenagem do hematoma. Resumo em inglês We report the unusual case of a 37 years old man with an epidural traumatic hematoma at the vertex with intracranial hypertension symptoms. The diagnostic was achieved with coronal cranial tomographic scans and a craniotomy was performed for hematoma removal.
Resumo em português A fratura do colo femoral, sem trauma associado, após a consolidação da fratura transtrocantérica é um evento raro. Os autores relatam um caso de fratura transtrocantérica tratada com PFN, que duas semanas após a retirada da síntese, apresentou fratura do colo femoral, que foi tratada com artroplastia parcial. Resumo em inglês Femoral neck fracture without associated trauma following consolidation of a transtrochanteric fractureis a rare event. The authors report a case of transtrochanteric fracture that was treated with PFN and which presented fracturing of the femoral neck two weeks after removal of the device. This occurrence was treated with partial arthroplasty.
Resumo em inglês The biosorption, based on the use of biomass for removal of ions is distinguished as an innovative and promising technology when compared with the traditional methods. In this context, the aim of the present work is to use Saccharomyces cerevisiae as biosorbent for the retention of Pb2+ metal ions. Factorial design was used for evaluation of the process. The observed equilibrium data were well described by Langmuir and Freundlich adsorption isotherms. The maximum adsorpti (mais) on capacity was 1486.88 mg/g. The results indicated that Saccharomyces cerevisiae is suitable for biosorption of Pb2+ metal ions.
Resumo em inglês The clay minerals montmorillonite (MT) and vermiculite (VT), previously treated with Ca2+, K+ and Na+, were employed in a sorption study with herbicides. The herbicides 2,4-D, diuron, alachlor and metolachlor showed no interaction with MT and VT. On the other hand, the triazines presented a good sorption process, close to 100% for ametrine removal and near to 56 and 69% for atrazine and simazine, respectively, by MT. These results suggest that the MT specie may be a good (mais) material for triazines removal from aqueous medium and an alternative phase to preconcentration process, besides to exhibit a good selectivity.
Estudo de adsorção de compostos sulfurados utilizando um diesel comercial dopado com benzotiofeno e dibenzotiofeno/ Study of adsorption of sulphur compounds employing a comercial diesel dopped with benzothiophene and dibenzothiophene
Resumo em inglês Desulphurization process by adsorption was studied employing a commercial diesel dooped with 1000 mg/L of benzothiophene and dibenzothiophene. The adsorbents materials employed were three types of activated alumina (acid, basic and neutral). For comparison, adsorption process was made also using oxidized diesel sample. The results showed that the adsorbents were selective for sulphur compounds removal from fuels. The contact time have influence in adsorption process achie (mais) ving 80% of removal for not oxidized dibenzothiophene. The three studied alumina types showed similar behavior and a greater selective in dibenzothiophene adsorption than benzothiophene. Dibenzothiophene removal is more effective in samples not oxidized, whereas the benzothiophene was almost totally removed in oxidized sample.
Estudo da degradação fotocatalítica de dimetil dissulfeto: avaliação estatistica do efeito do pH da temperatura e concentração do contaminante orgânico/ Assessment of the photocatalytic degradation of dimethyl disulfide: effect of pH, temperature and concentration of the organic contaminant
Resumo em inglês This work aimed to assess the photocatalytic degradation of a model odor compound (dimethyl disulfide, DMDS), found in liquid and gaseous wastes of plants for processing poultry byproducts. The effect of pH and temperature on adsorption and photocatalytic degradation was evaluated through factorial experimental designs. The results suggest the presence of an optimum region for adsorption, at 45.0 ºC and pH 4.0. In the photocatalytic runs an optimum for temperature and pH was also observed. At 45 ºC and pH 4.0 the removal of DMDS was 99% after 60 min of irradiation.
Estudo comparativo entre oclusão e não-oclusão no tratamento de abrasão corneana após retirada de corpo estranho da córnea/ Comparative study between eyepad and no eyepad in the treatment of corneal abrasion secondary to removal of corneal foreign body
Resumo em português OBJETIVO: Comparar a eficácia entre duas modalidades de tratamento das abrasões corneanas após a retirada de corpo estranho da córnea: curativo oclusivo e sem curativo. MÉTODOS: Cinqüenta e quatro pacientes com abrasão corneana após retirada de corpo estranho foram randomizados, de forma alternada, em dois grupos: um grupo com curativo oclusivo e o outro sem curativo. Os pacientes foram avaliados diariamente até a cura, em relação aos seguintes parâmetros: ár (mais) ea da abrasão corneana, intensidade de dor, presença de fotofobia, lacrimejamento, sensação de corpo estranho e visão turva. RESULTADOS: Não houve diferença estatisticamente significativa entre os dois grupos quanto a: área da abrasão corneana, tempo para se obter a cura, dor, fotofobia, lacrimejamento, sensação de corpo estranho e visão turva. Não ocorreu nenhuma complicação ocular ou sistêmica durante o tratamento em ambos os grupos. CONCLUSÃO: Abrasão corneana após retirada de corpo estranho, menor que 9 mm² , pode ser tratada apenas com antibiótico tópico de largo espectro e colírio cicloplégico, sem a necessidade do curativo oclusivo, tornando o tratamento mais simples e menos dispendioso. Resumo em inglês PURPOSE: To compare the effectiveness of two forms of treatment of corneal abrasion secondary to removal of corneal foreign body: eyepad and no eyepad. METHODS: Fifty-four patients with corneal abrasion secondary to removal of foreign body were randomized into two groups: the eyepad group and the no eyepad group. The patients were followed up daily, until complete healing, to evaluate: size of corneal abrasion, pain, photophobia, tearing, foreign body sensation, blurred v (mais) ision. RESULTS: There was no statistical difference between the two groups comparing: size of corneal abrasion, days until complete healing and amount of pain, photophobia, tearing, foreign body sensation or blurred vision. There were no systemic or ocular complications during the study. CONCLUSION: Corneal abrasion secondary to removal of foreign body, smaller than 9 mm² , can be treated with large spectrum topical antibiotic and cicloplegic drops alone without the need for eyepad, making treatment simpler and less expensive.
Resumo em português Em regiões endêmicas, a esquistossomose mansônica é responsável por uma alta taxa de morbimortalidade por doenças associadas à infestação do sistema hepático. O acometimento genital pela schistosomiasis mansoni é raro. Nós relatamos o primeiro caso de esquistossomose mansônica em vesícula seminal diagnosticado, incidentalmente, pelo exame histopatológico da próstata e vesículas seminais removidos cirurgicamente. Resumo em inglês In endemic regions, Mansoni schistosomiasis is responsible for high morbidity-mortality rates due to diseases associated with infestation of the hepatic system. Genital involvement caused by Mansoni schistosomiasis is rare. We report the first case of Mansoni schistosomiasis in the seminal vesicle, which was diagnosed incidentally by means of histopathological study of the prostate and seminal vesicles after surgical removal.
Efeito da composição das correntes do conversor das unidades de FCC no desempenho catalítico de aditivos DESOx/ Influence of the composition of the streams to the FCC converter unit on the catalytic performance of DESOx additives
Resumo em inglês Hydrotalcite-like compounds having Mg partially replaced by Cu or Mn were prepared and used as precursors for two mixed oxides (Cu-OM50 and Mn-OM50) that were evaluated for SOx removal in the presence of O2, NO and CO. Under SO2/O2 reaction system, SOx removal was slightly higher over Cu-OM50. The addition of CO and NO to the feed markedly hindered the SO2 oxidation over Cu-OM50 while no significant effect was observed for Mn-OM50. For the regeneration step, the use of pr (mais) opane instead of H2 reduces regeneration capacity, mainly for Cu-OM50. Mn-OM50 was less affected by the feed composition, suggesting that it was a promising additive for SOx removal.
Resumo em inglês Removal of hydrocarbons from aqueous effluents using biosorbents was investigated. The effluent was simulated by a dispersion of gasoline (simple hydrocarbons) in water. Corn-cob, wood powder, coconut mesocarp and sugar-cane bagasse were used as adsorbents and their performance verified by means of batch experiments performed in an agitated vessel. The influence of input variables such as hydrocarbon concentration, mass of biomass and agitation level on the adsorbents' ca (mais) pacity was studied by means of factorial design. The results indicated that, among the materials studied, coconut mesocarp and sugar-cane bagasse can be considered promising biomasses for treating aqueous effluents contaminated by hydrocarbons.
Descoloração redutiva de corantes azo e o efeito de mediadores redox na presença do aceptor de elétrons sulfato/ Reductive decolourisation of azo dyes and the effect of redox mediators in the presence of the electron acceptor sulfate
Resumo em inglês We investigated the impact of sulphate and the redox mediator Anthraquinone-2,6-disulfonate (AQDS) on the decolorization of the azo dyes Congo Red (CR) and Reactive Black 5 (RB5). In anaerobic reactors free of extra sulphate dosage, the color removal efficiency decreased drastically when the external electron donor ethanol was removed. In presence of an extra dosage of sulphate, CR decolourisations were 47.8% (free of AQDS) and 96.5% (supplemented with AQDS). The decolour (mais) isations achieved in both reactors with RB5 were lower than the ones found with CR. Finally, the biogenic sulphide contribution on azo dye reduction was negligiable.
Resumo em inglês The degradation of disperses dyes in aqueous solution and in effluents from textile industry has been investigated by photoelectrocatalytic oxidation using nanoporous thin films electrodes of Ti/TiO2. Samples of dispersil black dye and dispersil blue dye after 300 min of photoelectrolyzed at applied potential of +1.0 V and UV irradiation exhibited 100% of discoloration and 90% and 64% reduction total organic carbon, respectively. The proposed method was applied with succe (mais) ss in a textile industry effluent containing residues of these dyes, which after 300 min of treatment leads to reduction of 60% of COD and 64% removal of TOC.
Degradação de espécies nitroaromáticas e remediação de efluentes da indústria de explosivos, utilizando-se processos redutivos-oxidativos fundamentados no uso de ferro metálico/ Degradation of nitroaromatic compounds and remediation of residues from the explosive production by reductive-oxidative processes based on zero-valent iron
Resumo em inglês In this work the potentiality of reductive-oxidative processes based on zero-valent iron was studied aiming the degradation of nitroaromatic compounds and the remediation of residues from the explosive industry. The reductive process was applied as a continuous treatment system, using steel-wool as zero-valent iron source. The process permitted an almost total degradation of nitrobenzene, nitrophenol, nitrotoluene, dinitrotoluene and trinitrotoluene, probably with generat (mais) ion of the respective amine-derivative. The yellow-water residue, containing soluble trinitrotoluene, was notably modified by the reductive process, a fact that permitted a substantial enhancement of its biodegradability. Furthermore, the subsequent photo-Fenton process allowed TOC removal of about 80%.
Degradação de corantes ácidos por processos oxidativos avançados usando um reator com disco rotatório de baixa velocidade/ Acid dyes degradation by advanced oxidation processes using a low-speed rotating disk reactor
Resumo em inglês Three technologies were tested (TiO2/UV, H2O2/UV, and TiO2/H2O2/UV) for the degradation and color removal of a 25 mg L-1 mixture of three acid dyes: Blue 9, Red 18, and Yellow 23. A low speed rotating disc reactor (20 rpm) and a H2O2 concentration of 2.5 mmol L-1 were used. The dyes did not significantly undergo photolysis, although they were all degraded by the studied advanced oxidation processes. With the TiO2/H2O2/UV process, a strong synergism was observed (color rem (mais) oval reached 100%). Pseudo first order kinetic constants were estimated for all processes, as well as the respective apparent photonic efficiencies.
Degradação de benzeno, tolueno e xilenos em águas contaminadas por gasolina, utilizando-se processos foto-Fenton/ Degradation of benzene, toluene and xilenes in gasoline-contaminated waters by photo-Fenton processes
Resumo em inglês In this work the potentiality of photo-Fenton processes were investigated toward the degradation of aromatic hydrocarbons (BTXs) from water contaminated with gasoline. The main results demonstrated that BTXs can be quickly degraded by photo-Fenton process assisted by solar or artificial UV-A radiation, degradation that leads to generation of characteristic phenolic transient species (ie. phenol, hydroquinone and catechol). In the treatment of contaminated water by photo-F (mais) enton processes assisted by solar light, complete BTXs removal was observed in reaction times of about 5 min. Mineralization of about 90% was also observed by applying a multiple H2O2 addition system.
Resumo em inglês In this study the efficiency of advanced oxidative processes (AOPs) were investigated toward the degradation of aqueous solutions containing benzene, toluene and xylenes (BTX). The results indicated that BTX can be effectively oxidized by the UV-A-assisted photo-Fenton process. The treatment permits almost total degradation of BTX and removal of more than 80% of the phenolyc intermediates at reaction times of about 30 min. Preliminary investigations using solar light sugg (mais) est a good potentiality of the process for the treatment of large volumes of aqueous samples containing these polluting species.
Resumo em inglês A dye is a colored substance used to impart permanent color to other substances. Its most important use is in coloring textile fibers and fabrics. The removal of colour from dyehouse waste waters is currently a major problem in the textile sector. This paper provides an overview of the treatment technologies that can currently be used by the textile processor and the developments over the past decade with respect to the toxicological and ecotoxicological properties of synthetic organic dyes.
Comparação da eficiência do processo de ozonização e ozonização catalítica (Mn II e Cu II) na degradação de fenol/ Comparison of the efficiency of ozonation and catalytic ozonation (Mn II and Cu II) in phenol degradation
Resumo em inglês This paper discusses the results obtained with homogeneous catalytic ozonation [Mn (II) and Cu (II)] in phenol degradation. The reduction of total phenols and total organic carbon (TOC) and the ozone consumption were evaluated. The efficiency in phenol degradation (total phenol removal) at pH 3, with the catalytic process (Mn (II)), increased from 37% to 55% while the TOC removal increased from 4 to 63% in a seven-minute treatment. The ozonation process efficiency at pH 1 (mais) 0 was 43% and 39% for phenol and TOC removal, respectively. The presence of both metallic ions (Mn2+ and Cu+2) in the ozonation process resulted in a positive effect.
Cloreto de n-(2-hidroxil) propil-3-trimetil amônio quitosana como adsorvente de corantes reativos em solução aquosa/ Chitosan-n-2-hydroxypropyl trimethyl ammonium chloride as adsorbent for the removal of the reactive dye from aqueous solutions
Resumo em inglês The quaternary chitosan was synthesized by reaction of chitosan with glycidyl trimethylammonium chloride. it was characterized by infrared spectra and conductometric titration. Adsorption of reactive blue 4 (RB4) and reactive red 120 (RR120) by quaternary chitosan was studied from aqueous medium. Two kinetic adsorption models were tested: pseudo first-order and pseudo second-order. The experimental data best fitted the pseudo second-order model. The Langmuir isotherm mode (mais) l provided the best fit to the equilibrium data in the concentration range investigated and the maximum adsorption capacity determined was 415 mg (RR120) and 637 mg (RB4) of reactive dye per gram of adsorbent.
Caracterização de contaminantes presentes em sistemas de tratamento de esgotos, por cromatografia líquida acoplada à espectrometria de massas tandem em alta resolução/ Characterization of contaminants present in sewage treatment plants, by liquid chromatography high resolution tandem mass spectrometry
Resumo em inglês This work shows results on the characterization, by liquid chromatography coupled to high resolution tandem mass spectrometry (LC-IT-TOF-MS) with electrospray ionization, of organic compounds present in raw and treated effluents from a combined sewage treatment systems (upflow anaerobic sludge blanket-trickling filter). The sewage samples were prepared by C18 solid phase extraction and the spectra obtained from the various extracts were submitted to principal component an (mais) alysis to evaluate their pattern and identify the major deprotonated species. Some target compounds were submitted to semiquantitative analysis, using phenolphtalein as internal standard. The results showed the anaerobic step had little impact on the removal of anionic surfactants (LAS), fatty acids, and some contaminantes such as bisphenol A and bezafibrate, whereas the aerobic post-treatment was very efficient in removing these organics.
Biodegradação de tolueno e óleo de pescado em solos impactados utilizando surfactantes químico e biológico/ Biodegradation of toluene and fish oil in impacted soil using chemical and biological surfactants
Resumo em inglês The process of biodegradation of soils contaminated by animal (raw fish oil) and mineral (toluene) origin compounds was studied, verifying the influence of adding biosurfactants and chemical surfactants and nutrients in the media. The highest removal rate of fish oil was 59.47% obtained in the experiments containing biosurfactant and biostimulate in 90 days process. The highest removal rate of toluene was achieved in 14 days for experiments containing biosurfactant, chemi (mais) cal spreading and biosurfactant with biostimulation, showing great influence of evaporation on the process. The use of surfactants has shown to increase the contaminant bioavailability due to its higher degradation rate.
Resumo em inglês The adipic and phthalic acid esters are plasticizers, have low water solubility, high partition octanol/water coefficients (Kow) and accumulate in soil and sediments. These compounds are considered teratogenic, carcinogenic and endocrine disruptors chemicals. This study evaluated the bioremediation of tropical soil contaminated with plasticizers process wastes, in aerobic conditions, with and without introduction of acclimated bacteria. It was selected 200 kg of contamina (mais) ted tropical soil for the biodegradation study. The plasticizers concentrations in soil ranged between 153 mgDOA/kg up to 15552 mgDIDP/kg and after 90 days of biodegradation, the lower removal efficiencies were 72% with a 1-2 log simultaneous bacterial growth.
Resumo em inglês The main objective was to study the treatment of wastewater generated by the oil industry. This work consisted of tests of electroflocculation with alternate current (AC), and chemical coagulation. The removal efficiencies of organic load were evaluated by the removal of oils and greases, color and turbidity. The parameters investigated were the change in alternate current frequency, the initial pH, the distance between electrodes, the applied potential and time lapse. Fr (mais) om the results, one may conclude that the electroflocculation process is potential applicability to the effluent studied, while chemical coagulation was not successful.
Avaliação da cicatrização induzida pela membrana de celulose porosa depois da retirada total da pele em dorso de ratos/ Assessment of induced healing by porous cellulose membrane after complete removal of a skin segment from the back of rats
Avaliação da biodegradabilidade de efluentes têxteis do beneficiamento secundário de malhas de poliéster tratados com Reagente de Fenton/ Biodegradability evaluation of textile effluents from the secundary process of polyester fibers treated with Fenton's Reagent
Resumo em inglês From the environmental point of view, the textile sector is outstanding for the generation of large amounts of biorecalcitrant effluents. In this paper the textile effluent biodegradability, both before and after its treatment with Fenton's Reagent, were compared by means of biologic tests. These tests showed that the Fenton treatment lowered the biodegradabilty of practically all tested effluents, except one specific effluent from a scouring bath of polyester fibers, which achieved a 93% COD removal. This removal was due to a significant phase separation (oil/water).
Aplicação de radiação UV artificial e solar no tratamento fotocatalítico de efluentes de curtume/ Application of artificial and solar UV radiation in the photocatalytic treatment of a tannery effluent
Resumo em inglês Tannery effluents are very dangerous for the environment since they contain large amounts of dangerous and biorecalcitrant contaminants (organic matter and Cr(VI)). This paper reports the efficiency of heterogeneous photocatalysis, based on the application of solar and artificial radiation, furnished by UV lamps, using TiO2 fixed on a flat plate, in the treatment of synthetic effluents. The results of COD and Cr(VI) demonstrate that the use of solar radiation is the most (mais) efficient way to perform the photocatalytic treatment of these effluents since a minimum removal of 62 and 61% was observed for Cr(VI) and organic matter, respectively.
Resumo em inglês The aim of this work is to evaluate the use of natural zeolites to remove the NH4+ that remains in effluents from swine facilities which were submitted to physico-chemical and biological treatments. Experiments were made in batch made adding 5% (w/w) of adsorbent (0.6-1.3 and 3.0-8.0 mm) to synthetic and real swine facilities effluents. The results show that ammonium removal is influenced by adsorbent particle size and the presence of other ions in the effluent. The adsor (mais) ption equilibrium was described by Langmuir as well as Freundlich isotherms and the kinetic data fitted well a pseudo-second order model.
Aplicação da tecnologia de eletrofloculação na recuperação do corante índigo blue a partir de efluentes industriais/ Application of the electroflocculation technology for the recovery of indigo blue from industrial effluents
Resumo em inglês The indigo blue dye is widely used in the textile industry. When discarded, besides polluting the environment, it affects the appearance and transparency of aquatic bodies, causing damage to flora and fauna. The removal of this dye from industrial effluents is difficult due to its resistance towards degradation. This work proposes the recovery of indigo blue by electroflocculation, as a subsidy for the treatment of effluents from the jeans industry.
Resumo em inglês The removal of As(V) by a crosslinked iron(III)-chitosan adsorbent was evaluated under various conditions. The adsorption capacity of CH-FeCL was around 54 mg/g of As(V). The kinetics of adsorption obeys a pseudo-first-order model with rate constants equal to 0.022, 0.028, and 0.033 min-1 at 15, 25 and 35 ºC respectively. Adsorption data were well described by the Langmuir model, although they could be modeled also by the Langmuir-Freundlich equation. The maximum adsorpt (mais) ion capacity, calculated with the Langmuir model, was 127 mg g-1 of As(V). The inhibition by competing anions is dependant on their kind and valence.
Adsorção de Cr(VI) em esferas reticuladas de quitosana: novas correlações cinéticas e termodinâmicas utilizando microcalorimetria isotérmica contínua/ Adsorption of Cr(VI) onto crosslinked chitosan microbeads: new kinetic and thermodynamic correlations using continuous isothermal microcalorimetry
Resumo em inglês The synthesis and characterization of crosslinked chitosan microbeads and their application in the removal of Cr(VI) are described. New kinetic and thermodynamic parameters of Cr(VI) adsorptions processes were found using continuous isothermal calorimetry. All adsorption processes are exothermic in nature. However, a multivariate statistical analysis have pointed out that adsorption enthalpies were affected by important binary interactions of the initial Cr(VI) in solutio (mais) n and temperature. The adsorption energetic data were well fitted to a kinetic exponential model, which have indicated fractionary adsorption kinetic orders.