O setor público e a avaliação do capital intelectual: um estudo de caso no Instituto Federal de Goiás, segundo o modelo de Medição do Capital Intelectual no setor público proposto por Queiroz em 2003

Versão final (Esta versão contém as críticas e sugestões dos elementos do júri)A medição do Capital Intelectual, tradicionalmente composta pelos capitais humano, estrutural e relacional, é um tema incomum nas autarquias do setor público, o que originou a necessidade de pesquisar tal aspecto. No primeiro momento, foi constatada, por meio do referencial teórico, a possibilidade de aplicar um modelo para esse setor; logo, tencionou-se operacionalizar o modelo de Medição do Capital Intelectual no setor público proposto por Queiroz (2003) e informar às pessoas-chave e à gestão a existência de um método que auxilie na gestão desse conhecimento e na tomada de decisões. Para tanto, utilizou-se o estudo de caso, com aplicação de questionário on-line aos servidores da instituição pública de ensino denominada como Instituto Federal de Educação, Ciência e Tecnologia de Goiás – Câmpus Itumbiara. Quanto ao tipo de metodologia, foi realizada uma análise de conteúdo conjugada com a descrição estatística das respostas obtidas. Como principal resultado, evidencia-se a operacionalização do referido método, em que a dimensão de Relações Externas, no conjunto formado por ela e Capital Humano, Organização Interna, Qualidade e Transparência, obteve a melhor pontuação, o que demonstra que a instituição cumpre com os objetivos relacionados aos stakeholders. Pelo fato de as notas finais para todas as dimensões se encontrarem abaixo da média (50%), de acordo com Queiroz (2003), gera-se um passivo intelectual. As principais limitações do estudo são o tipo de instrumento aplicado e o curto período para a coleta de dados, o que sugere entrevistas e investigações em outras instituições. Desse modo, os Institutos Federais, como autarquias da administração pública, possuem um vasto campo para investigar os elementos que permeiam o Capital Intelectual e que podem agregar valor a eles.The measurement of Intellectual Capital, traditionally composed by human, structural and relational capital, is an uncommon theme in public sector autarchies, which led to the need to research this aspect. In the first moment it was verified, through the theoretical reference, the possibility of applying a model for this sector; therefore, it was intended to operationalize the Intellectual Capital Measurement model in the public sector proposed by Queiroz (2003) and to inform key people and management about the existence of a method that assists in the management of this knowledge and in decision-making. For this purpose, the case study was required, with the application of an on-line questionnaire to the employees of a public educational institution named as Instituto Federal de Educação, Ciência e Tecnologia de Goiás – Câmpus Itumbiara, Brazil. Regarding the type of methodology, a content analysis was performed closely with the statistical description of the obtained responses. As a main result, it is evident the operationalization of the reffered method, in which the External Relations dimension, in the group composed of it and Human Capital, Internal Organization, Quality and Transparency, has taken the best score, which shows that the institution complies with the objectives related to the stakeholders. As the final scores for all dimensions are below the average (50%), according to Queiroz (2003), this fact generates an intellectual liability. The main limitations of the study are the type of instrument applied and the short period for data collection, which suggests interviews and investigations in other institutions. Therefore, the Federal Institutes, as autarchies of the public administration, have a vast field to investigate the elements that permeate Intellectual Capital that can add value to them

Anatomical aspects, chemical analysis and cytotoxic effect of the essential oil from leaves of Casearia arborea (Salicaceae)

The genus Casearia (Salicaceae) is found in sub-tropical and tropical regions of the world and comprises about 200 species. In Brazil, there are about 48 species and 12 are registered in the State of Rio de Janeiro; including Casearia arborea (Rich.) Urb. Essential oil was obtained from the fresh leaves by hydrodistillation and analyzed by GC-MS and GC-FID. The cytotoxic effect was determined by WST-1 assay. Chemical analysis of the essential oil revealed a very diversified (n = 37 compounds) volatile fraction composed mainly of non-oxygenated sesquiterpenes (90.2%). These sesquiterpenes included byciclogermacrene (18.7%), germacrene D (12.1%) and α- humulene (11.5%). In addition, the essential oil demonstrated cytotoxic effects against A549 tumor cells in the concentration of 4 μg/mL (EC50) (p < 0.05)

ACID ROCK DRAINAGE NEUTRALIZATION BY BAUXITE RED MUD: LABORATORY BATCH TESTING : Neutralização de Drenagem Ácida de Rochas com Lama Vermelha de Bauxita: Ensaios de Batelada em Laboratório

Acid Rock Drainage (ARD) is one of the world's most challenging environmental issues. Alkaline amendments to barriers for ARD prevention or direct ARD alkaline treatment have been routinely used for ARD management. In turn, bauxite red mud (BRM) is an alkaline residue from the alumina industry, with annual average production close to 120 million tons. So the use of BRM for ARD neutralization seems to be a good alternative and must be investigated. The main objective of this experiment is to assess suitable proportions of BRM to treat ARD under the perspective of waste management procedures. So, laboratory short-term batch equilibrium tests were carried out using different volumetric and mass proportions. The use of a volumetric approach was intended to simulate the mixture of BRM pulp with the ARD liquid solutions, while the mass approach refer to the mixtures of dewatered BRM and ARD. The pH and metal removal percentage, called here as extraction, were respectively used as neutralization and treatment efficiency parameters. The results have showed that BRM was efficient for ARD neutralization on BRM volumetric proportions greater than 60% and solid (BRM):liquid(ARD) ratio of 1:1.5. This ratio result on extraction values greater than 90% for most of the ARD chemicals.Resumo - A Drenagem Ácida de Rochas (ARD) é uma das questões ambientais mais desafiadoras do mundo. Correções alcalinas nas barreiras para prevenção de ARD ou tratamento alcalino direto de ARD têm sido usados rotineiramente para o manejo de ARD. Por sua vez, a lama vermelha de bauxita (BRM) é um resíduo alcalino proveniente da indústria de alumina, com produção média anual próxima de 120 milhões de toneladas. Portanto, o uso do BRM para neutralização da DRA parece ser uma boa alternativa e deve ser investigado. O principal objetivo deste experimento é avaliar proporções adequadas de BRM para tratar ARD sob a perspectiva dos procedimentos de gestão de resíduos. Assim, foram realizados testes laboratoriais de equilíbrio de lotes de curto prazo utilizando diferentes proporções volumétricas e de peso. A utilização da abordagem volumétrica teve como objetivo simular a mistura da polpa de BRM com as soluções líquidas de ARD, enquanto a abordagem de massa refere-se às misturas de BRM desidratado e ARD. O pH e a porcentagem de remoção de metal, aqui denominados de extração, foram utilizados respectivamente como parâmetros de neutralização e eficiência do tratamento. Os resultados mostraram que o BRM foi eficiente na neutralização da ARD em proporções volumétricas de BRM superiores a 60% e relação sólido (BRM):líquido (ARD) de 1:1,5. Esta relação resulta em valores de extração superiores a 90% para a maioria dos produtos químicos da ARD. Palavras-chave: Tratamento de Drenagem Ácida de Rochas. Lama Vermelha de Bauxita. Neutralização. Reuso. Testes em lote. Resíduo de Alumínio.   Abstract - Acid Rock Drainage (ARD) is one of the world's most challenging environmental issues. Alkaline amendments to barriers for ARD prevention or direct ARD alkaline treatment have been routinely used for ARD management. In turn, bauxite red mud (BRM) is an alkaline residue from the alumina industry, with annual average production close to 120 million tons. So the use of BRM for ARD neutralization seems to be a good alternative and must be investigated. The main objective of this experiment is to assess suitable proportions of BRM to treat ARD under the perspective of waste management procedures. So, laboratory short-term batch equilibrium tests were carried out using different volumetric and mass proportions. The use of a volumetric approach was intended to simulate the mixture of BRM pulp with the ARD liquid solutions, while the mass approach refer to the mixtures of dewatered BRM and ARD. The pH and metal removal percentage, called here as extraction, were respectively used as neutralization and treatment efficiency parameters. The results have showed that BRM was efficient for ARD neutralization on BRM volumetric proportions greater than 60% and solid (BRM):liquid(ARD) ratio of 1:1.5. This ratio result on extraction values greater than 90% for most of the ARD chemicals.   Keywords: Acid Rock Drainage Treatment. Bauxite Red Mud. Neutralization. Reuse. Batch Testing. Aluminum Residue

Manganese adsorption kinetics on exhausted zeolites.

Efluentes ricos em mangan?s, como os das ind?strias extrativas, de vidro e cer?micas, plantas de galvaniza??o, entre outros, s?o considerados um problema ambiental devido principalmente ao seu poder toxicol?gico. O ?on mangan?s ? um poluente devido ?s suas propriedades organol?pticas e ? considerado um metal de dif?cil remo??o devido ? sua alta solubilidade, sendo usualmente encontrado em efluentes na forma do ?on divalente Mn2+. Diversos m?todos de tratamento t?m sido aplicados a esses tipos de efluentes com objetivo de enquadramento dos mesmos ? legisla??o ambiental vigente. Uma dessas alternativas ? a adsor??o/troca i?nica tanto em batelada como em colunas de leito fixo, particularmente quando a concentra??o de metais ? baixa. Visando o tratamento de efluentes que cont?m o ?on mangan?s, o presente trabalho descreve a remo??o do ?on pelo processo de adsor??o/troca i?nica utilizando uma ze?lita exaurida. Foram realizados estudos cin?ticos nas temperaturas de 25?C, 35?C, e 60?C, que revelaram uma alta remo??o desde o in?cio do contato entre a solu??o rica em mangan?s e a ze?lita sendo que o equil?brio foi atingido ap?s percorridas 3 horas de experimento. Os dados experimentais se ajustaram melhor ao modelo de pseudossegunda ordem para adsor??o do ?on mangan?s na ze?lita investigada. Al?m disso, observou-se nesses experimentos o aumento da temperatura eleva o carregamento e a partir do valor da energia de ativa??o calculada de 55,4KJ/mol tem-se indica??o de que o processo de adsor??o em quest?o ? uma quimiossor??o.Galvanizing plants as well as the mining, glass and ceramics industries among others can produce manganese-laden effluents, which are considered an environmental issue mainly due to their organoleptic properties and because the highly soluble Mn2+ ion is difficult to remove from most wastewaters when only pH control is applied. Thus several treatment methods have been proposed to treat these effluents so that they can comply with environmental regulations. One of such treatments is adsorption/ion exchange (either batchwise or fixed bed) particularly when the metal concentration is low. Biosorbents, ion exchange resins, and zeolites have been investigated as potential sorbents for manganese. Aimed at treating manganese containing effluents, the current work describes manganese removal by adsorption/ion exchange in a spent faujasite zeolite used in the oil industry. Batch kinetic studies were carried out at 25?C, 35?C and 60?C with this spent zeolite and revealed that equilibrium was reached within 3 hours, whereas the experimental kinetic data could be described by the pseudo-second order model. It was observed that the loading rate increased with temperature with an activation energy of 55,4kJ/mol calculated from the rate constant values; an indication of chemisorption during manganese adsorption on the spent faujasite zeolite

Effect of EDTA on quartz and hematite flotation with starch/amine in an aqueous solution containing Mn2+ ions.

In this paper, a detailed study of the influence of Mn2+ ions on quartz and hematite flotation (at pH 10.5 with starch/amine as depressor/collector) in the absence and presence of ethylenediaminetetraacetic acid (EDTA) is presented. By using zeta potential measurement and a careful analysis of manganese species present in water for dosages in which manganese hydroxide precipitated, we confirmed that the depression of both minerals by Mn2+ ions is due to the following: (i) the adsorption of Mn hydroxy complexes (Mn2(OH)3+ and Mn(OH)+); (ii) Mn2+ and mainly (iii) the precipitation of Mn(OH)2 on mineral surfaces. These effects hindered the adsorption of amine species on the surfaces of the minerals (quartz and hematite). EDTA was used to complex Mn2+ to restore the recoveries of both minerals. This was confirmed by the species distribution diagrams of Mn and EDTA?Mn in water. Conditioning with starch followed by amine at pH 10.5 enabled a selective separation of these minerals

Batch removal of manganese from acid mine drainage using bone char.

The present study investigated batch kinetics and the batch equilibrium of manganese removal from acid mine drainage (AMD) using bone char as an adsorbent. Equilibrium tests revealed that the Langmuir-based maximum manganese uptake capacity was 22 mg g-1 for AMD effluents and 20 mg g-1 for laboratory solutions at a pH ranging from 5.5 to 5.7. The pseudo-second order model best described the manganese kinetics within bone char. Manganese removal was mainly influenced by the operating variables of the solid/liquid ratio and the pH of the aqueous phase. In fact, metal uptake was favored at nearly neutral pH values. The effect of particle size and temperature proved to be insignificant for the investigated operating range. This work also evaluated the mechanism for manganese removal using bone char. Results showed that intraparticle diffusion is the main rate-limiting step; however, additional contributions from boundary layer diffusion may well affect this removal when particles of smaller sizes are used. The final concentration of fluoride and other metals present in the AMD effluent was in agreement with the concentration limit set forth by Brazilian legislation. The present study demonstrated that bone char is a suitable material to be used for the removal of manganese from AMD effluents

Influence of sodium fluorsilicate addition on manganese minerals and quartz floatability with sodium oleate.

Esse trabalho apresenta e discute resultados de ensaios de microflota??o e determina??o de potencial zeta dos minerais rodonita, rodocrosita e quartzo, na presen?a de fluorsilicato e oleato de s?dio em pH 9 e pH 11. Verificou-se que, para concentra??es de Na2SiF6 abaixo de 10mg/L, houve maior depress?o do quartzo em rela??o ? rodonita no valor de pH 9 e que a flotabilidade da rodocrosita foi pouco afetada para os valores de pH 9 e 11. Resultados de medidas de potencial zeta versus pH indicaram que o ponto isoel?trico da rodonita (pH=2,8) coincidiu com o reportado em literatura, enquanto que os valores determinados para quartzo (pH<2,0) e rodocrosita (pH=10,8) apresentaram pequena diverg?ncia. Para os tr?s minerais, a presen?a de oleato e/ou silicato de s?dio foi capaz de tornar mais negativa a magnitude do potencial zeta dos tr?s minerais em meio b?sico. Fundamentando-se nos resultados experimentais e, tamb?m, na especia??o dos reagentes estudados (oleato e fluorsilicato de s?dio), foi poss?vel fazer infer?ncias sobre mecanismos de adsor??o dos mesmos sobre os tr?s minerais de interesse.This work presents and discusses results from zeta potential measurements and flotation response of rhodonite, rhodochrosite and quartz, in the presence of sodium fluorsilicate and sodium oleate. At concentrations of Na2SiF6 smaller than 10mg/L, at pH 9, quartz is more intensively depressed than rhodonite, whereas the flotation response of rhodochrosite is slightly affected either at pH 9 or pH 11. Results from measurements of zeta potential versus pH indicate that IEP of rhodonite (pH=2.8) is similar to those reported in literature, whereas the value o IEP of quartz (pH<2.0) and rhodochrosite (pH=10,8) differ slightly from literature. Zeta potential of rodonite, quartz and rhodochrosite, in the presence of sodium fluorsilicate and/or sodium oleate, become more negative at basic medium. Based on the experimental results and collector (sodium oleate) plus depressant (sodium fluorsilicitate) speciation, some inference on the adsorption mechanisms of these reagents upon rhodonite, quartz and rhodochrosite is maintained

Column Bioleaching of Fluoride-Containing Secondary Copper Sulfide Ores: Experiments With Sulfobacillus thermosulfidooxidans

Bioleaching is a mature technology, which is widely employed commercially in the leaching of primary sources of metals (ores, concentrates, and mine residues). The current work discussed the effects of aluminum sulfate additions to the growth medium, PLS recirculation and bleeding on the column bioleaching of secondary copper sulfide ores with a significant content of fluoride-containing minerals. Fluoride is toxic to bacteria at the pH of bioleaching but its toxicity may be overcome in the presence of soluble aluminum and ferric iron. Therefore, experiments were carried out in 10 × 100 cm height aerated columns, loaded with 10 kg of crushed and agglomerated copper ore and inoculated with Sulfobacillus thermosulfidooxidans. Initially, fluoride concentrations of up to 2.5 g/L in the pregnant leach solution were observed due to the fast dissolution of fluoride-bearing minerals. Aluminum was added to the leaching solution to reduce the Al/F ratio so that the concentration of HF (the main toxic species) was decreased, but while the total fluoride concentration was higher than that of aluminum, the bacterial population as low. Therefore, the current work emphasizes that it is possible to set up conditions to enable bioleaching even at high fluoride concentrations. Following this approach, copper extractions above 90% were achieved for a H2SO4 consumption ranging from 128.8 to 206.1 Kg/ton

Technological characterization of an exaurid zeolite for removal of Mn2 + ions

As ze?litas apresentam importante propriedades fisico-qu?micas que aliadas a sua disponibilidade e seu baixo custo viabilizam sua aplica??o em v?rios processos industriais. Atualmente tem-se dado enfoque para utiliza??o de ze?litas na adsor??o de metais no tratamento de ?gua e de efluentes industriais. Assim, o presente trabalho teve como objetivo a caracteriza??o tecnol?gica de uma ze?lita, visando atestar a viabilidade de sua utiliza??o na remo??o de ?ons Mn2+(aq) em diferentes condi??es experimentais. O material utilizado neste trabalho era uma ze?lita sint?tica exaurida utilizada como catalisador no craqueamento de petr?leo. Inicialmente, realizou-se a ativa??o da ze?lita com solu??o de NaOH, 1 mol.L-1. Em seguida, foi feita a caracteriza??o da mesma e sua aplica??o nos ensaios de adsor??o com solu??o sint?tica de Mn2+ a 50 mg.L-1, realizados em batelada. Foram investigados valores de pH entre 4 e 8, e temperatura entre 25?C e 70?C. Observou-se que a ze?lita foi identificada, por difra??o de raios-X, como Faujasita. O pH ?timo de adsor??o sem risco de remo??o por precipita??o foi de 6,5 e a melhor temperatura, 25?C. O tempo de equil?brio da adsor??o do Mn2+(aq) por adsor??o foi de 4 horas. Nessas condi??es, obteve-se um carregamento de 10,8 mg Mn2+-g ze?lita. Os resultados mostraram o potencial de aplica??o deste material para processos de remo??o de ?ons mangan?s presentes em solu??es aquosas.Zeolites have important chemical properties which combined with their availability and low-cost support their application in various industrial processes. Currently, much attention has been given to their use for metal sorption from wastewaters and industrial effluents. Therefore, the present study carried out a technological characterization of a waste zeolite sample followed by assessing its application in the removal of Mn2+ ions in different experimental conditions. The material used in this work was a spent synthetic zeolite used as a petroleum cracking catalyst. The zeolite was firstly washed in a 1 mol.L-1 NaOH solution. After characterization, batch sorption experiments were carried out with 50 mg.L-1 Mn2+ synthetic solutions. The pH values were set between 4 and 8 and temperature in the 25-70?C range. The zeolite phase was identified by X-ray diffraction as faujasite. The optimum pH for manganese sorption was 6.5 and the optimum temperature value was 25?C. The time required for equilibrium to be achieved was 4 hours, which enabled to attain a loading of 10.8 mg Mn2+/g zeolite. The results herein presented confirmed the potential application of this material for manganese ions sorption.Zeolites have important chemical properties which combined with their availability and low-cost support their application in various industrial processes. Currently, much attention has been given to their use for metal sorption from wastewaters and industrial effluents. Therefore, the present study carried out a technological characterization of a waste zeolite sample followed by assessing its application in the removal of Mn2+ ions in different experimental conditions. The material used in this work was a spent synthetic zeolite used as a petroleum cracking catalyst. The zeolite was firstly washed in a 1 mol.L-1 NaOH solution. After characterization, batch sorption experiments were carried out with 50 mg.L-1 Mn2+ synthetic solutions. The pH values were set between 4 and 8 and temperature in the 25-70?C range. The zeolite phase was identified by X-ray diffraction as faujasite. The optimum pH for manganese sorption was 6.5 and the optimum temperature value was 25?C. The time required for equilibrium to be achieved was 4 hours, which enabled to attain a loading of 10.8 mg Mn2+/g zeolite. The results herein presented confirmed the potential application of this material for manganese ions sorption