Enzymatic Inhibition By Lignin During Second Generation Ethanol Production

An important hindrance to commercialization of lignocellulosic ethanol is the high cost of enzymes. Reducing enzyme loadings is necessary to reduce costs. Knowledge of the inhibitors of these enzymes is necessary to better inform enzyme development and process design. Five factors have been identified: soluble inhibitors, solid lignin adsorption, product inhibition, mixing efficiency and oxygen deactivation of the enzymes that hydrolyze cellulose to glucose. These factors are intertwined and properly assessing them individually require the elimination of the others. Isolating each factor, however, has not been done throughout literature leading to lumped constants. Soluble inhibitors reduce conversion sharply leading to high enzyme loadings and impeding the evaluation of any of the other factors. Through washing, the soluble inhibitors may be eliminated, and only washed biomass (either sugar cane bagasse or corn stover) was used to study the other factors. This work further investigates adsorption on lignin, mixing, and the effect of air on washed pretreated sugarcane bagasse and corn stover. Studies of enzyme adsorption on lignin, showed lignin/enzyme interaction was temperature dependent and proportional to pretreatment severity. Lowering reaction temperatures to 30°C, eliminated enzyme adsorption and was opposite to what was expected, indicating a possible entropic process. On a practical basis, the additional free enzyme partial makes up for the lower activity of the enzyme mixture that occurs due to reduced reaction rate at the lower temperature of 30°C. Lower hydrolysis rates also require longer reaction times to achieve the same extent of conversion to glucose. An alternative to counter adsorption of enzyme on lignin occurs by regulating the amount of lignin exposed by adjusting pretreatment conditions. At higher temperatures a large portion of lignin is solubilized and redeposited, increasing lignin exposure and adsorption is higher. At a lower severity, lignin is less exposed, and adsorption is lower. However, higher severity is needed to increase the accessibility of cellulose, thereby facilitating accessibility and conversion. For sugarcane bagasse a 10.74 severity pretreatment (200°C for 20 minute) using liquid hot water resulted in minimal protein adsorption and therefore was interpreted to coincide with a small extent of lignin exposure, as qualitatively confirmed using SEM. Efficient conversion (71- 76%) was achieved when hydrolysis with 6.5 mg of Cellic CTEC3 / g total solids. A more recalcitrant biomass would require a more intense pretreatment to be hydrolyzed at satisfactory levels. Mixing and product inhibition were more intricately linked than the others. When efficient mixing was achieved, product inhibition was decreased relative to cases where mixing was not readily achieved. In these runs, concentrations of pretreated and washed corn stover were at initial concentrations of 10 to 200 g/L. At 200 g/L, the higher efficiency led to faster liquefaction of biomass in the early stages. Faster liquefaction resulted in significantly high glucose conversions (up to 47% final yields) after 72 hours of hydrolysis compared to minimally liquefied material where conversion was 34% Efficient mixing allowed deactivation due to air to be evaluated properly. This factor is the least understood in the literature and has a potentially major effect on the amount enzyme required for a given level of hydrolysis. Deactivation was isolated and observed by measuring conversion in a mixed 1 L reactor either in the presence of absence of air, except in these experiments with a different enzyme formulation, Cellic CTEC2 was used at 3.6 mg protein (Cellic CTEC2) / g solids. Cellic CTEC2 has lower activity, and the lower amount ensured that differences between the two conditions would be more obvious. Air was shown to decrease conversion by 10 to 15% with lower loss of activity corresponding to high solids loading. The impact of unfavorable conditions (presence of lignin, inefficient mixing and inadequate air exposure) can be minimized by adjusting the biomass pretreatment and hydrolysis processes. The extent of adsorption of cellulolytic enzymes on lignin can be reduced by lowering hydrolysis temperature or reducing pretreatment severity. Efficient mixing facilitates liquefaction and increases final glucose conversion from cellulose compared to inefficient mixing methods. Limiting the presence of air increases enzyme activity and the associated final conversions. Adoption of the combined adjustments reduced enzyme loading by 50% (from 6 FPU to 3 FPU / g solids) for the enzyme Cellic CTEC2

Sugarcane bagasse hydrolysis enhancement using BSA

Lignocellulose is composed of polysaccharides linked to lignin and other aromatic compounds, making the sugars not readily available to fermentation. This entails that biomass must go through the unit operations of pretreatment and enzyme hydrolysis. Pretreatment opens the structure to allow the enzymes to act on and hydrolyze cellulose and hemicellulose to glucose and/or xylose which in turn are fermented to ethanol. Concomitantly, the enzymes interact with soluble phenols and insoluble solids derived from lignin that inhibit hydrolysis. This leads to high enzyme loadings and higher production costs. Soluble phenols can be eliminated through washing. Insoluble lignin, however, demands another approach. Using bovine serum albumin (BSA) and pretreated sugarcane bagasse, the effect of blocking solid lignin from adsorbing enzymes during hydrolysis after 72 hours was evaluated. Hydrolysis was carried using 6.25 FPU (Cellulase 13P) and 12.5 IU (Novozyme 188) /g solids (10 mg protein/g solids) at pH 4.8 and 50°C. The conversion was generally higher when BSA was present, 51% (±1%) vs 42% (±1%) with 1.5% solids loading and 46% (±1%) vs 40% (±1%) with 8% solids loading. The use of BSA produced an increase in the final conversion (p-value \u3c 0.001), but conversion decreased as loadings increased. This has been observed in multiple other studies and cannot be explained by a single factor. The basis of this phenomenon is being investigated. Initial experiments that adjusted the enzyme preparation to 2.5 FPU/g glucan (10.5 mg protein/g glucan) of Cellic CTEC3 and improved the mixing of the slurry elevated the conversion to 72% (±5%) without BSA and 76% (±10%) with it, at 1% (w/v) solids loading and 73% (±6%) without BSA and 80% (±10%) with it, at 10% (w/v) solids loading

Information Management Capability as Competitive Imperfection in the Strategic Factor Market of Big Data

The interest of the organizations in developing Big Data strategies is increasing significantly. However, the expectation of the value of these benefits and of the costs involved in acquiring or developing these solutions are not homogeneous for all of the firms, generating competitive imperfections in the market of strategic resources. Using Information Management Capability (IMC) as a premise to provide the required unique insight for Big Data strategies to be successful, this article proposes to analyze IMC as an imperfection agent in the market of strategic resources of Big Data. The formulated hypotheses were tested from a survey of 101 valid participants and analyzed with SEM-PLS. The results indicate a positive IMC influence on value expectation and a negative one on cost expectation. Cost expectation inversely affects the intent to purchase or develop the resources to implant Big Data strategies. Value expectation has a positive effect in both intents

Impact of Changes in Accounting Standards in Debt Ratios of Firms: Evidence in Brazil

This research investigates the impact of changes in debt ratios of Brazilian firms due to the IFRS adoption. We make a comparison between the forecast of the time-series of debt ratios accounted until 2007 for the span from 2008 to the first quarter of 2015 with those effectively accounted from 2008 to the first quarter of 2015 derived from the new accounting standard. The research utilizes SARIMAX model and Chow’s (1960) structural break forecast test, controlling for changes originating from the macroeconomic environment as well. We find evidence of significant changes in the debt ratio towards both higher and lower debt with predominance of greater ratios. This result is consistent with past literature in Europe, Australia and New Zealand. Nevertheless, we do not find evidence of a structural break in the Financial Dependency ratio. Moreover, there is no evidence of any distinct effects across different industries. The research provides new evidence confirming the informational effects of IFRS by utilizing a robust time-series model with macroeconomic controls in an innovative approach towards the accounting environment.A pesquisa investiga o impacto de mudanças na representação contábil do endividamento de firmas brasileiras a partir da comparação entre a projeção da série temporal dos indicadores de endividamento apurados até 2007 para o período de 2008 até o primeiro trimestre de 2015 e os efetivamente apurados de 2008 ao primeiro trimestre 2015, oriundos de novo padrão contábil. Utilizou-se modelo SARIMAX e teste de previsão de quebra estrutural de Chow (1960), controlando-se alterações oriundas da economia. Identificou-se alteração significante no indicador de Endividamento, tanto no sentido de reportar maior quanto menor endividamento, mas com predominância de incremento no índice. O resultado é consistente com pesquisas em países europeus, Austrália e Nova Zelândia. Contudo, não se identificou alteração no indicador de Dependência Financeira, e não se constataram efeitos distintos entre setores econômicos. A pesquisa contribui confirmando impactos informacionais relevantes e significantes pela adoção de padrão contábil no Brasil voltado para o objetivo informacional; ademais, utilizou-se método inovador no âmbito contábil, qual seja de análise do comportamento temporal da variável, com controle de implicações macroeconômicas efetivas

Towards a Multimodal Silent Speech Interface for European Portuguese

Automatic Speech Recognition (ASR) in the presence of environmental noise is still a hard problem to tackle in speech science (Ng et al., 2000). Another problem well described in the literature is the one concerned with elderly speech production. Studies (Helfrich, 1979) have shown evidence of a slower speech rate, more breaks, more speech errors and a humbled volume of speech, when comparing elderly with teenagers or adults speech, on an acoustic level. This fact makes elderly speech hard to recognize, using currently available stochastic based ASR technology. To tackle these two problems in the context of ASR for HumanComputer Interaction, a novel Silent Speech Interface (SSI) in European Portuguese (EP) is envisioned.info:eu-repo/semantics/acceptedVersio

A CRISE ECOLÓGICA NA AGRICULTURA DO ESTADO DO MARANHÃO E A REPRODUÇÃO SOCIAL DO TRABALHO FAMILIAR

Este texto tem o propósito de apresentar uma analise socioeconômica ecológica das transformações históricas que afetam a unidades econômicas camponesas no Estado do Maranhão. Os dados oficiais disponíveis permitem inferir a existência de uma crise ecológica que ameaça a sustentabilidade das mesmas. A reversão desse processo requer o desenvolvimento de pesquisas que qualifiquem o conjunto dos problemas existentes e desenhe uma matriz de indicadores de sustentabilidade para viabilizar a reestruturação tecnológica dessas unidades produtivas. Nesse sentido, esta reflexão tem a pretensão de subsidiar a intervenção dos atores sociais e das instituições governamentais envolvidas com o processo de Reforma Agrária no Brasil

Título de crédito eletrônico e agronegócio

- Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.- Localização na estante: 347.735'243:004(81) F866

Population structure of the broad-snouted caiman (Caiman latirostris) in natural and man-made water bodies associated with a silvicultural landscape

The broad-snouted caiman (Caiman latirostris) is a South American crocodilian with a wide geographical distribution. Water bodies originally occupied by the species have suffered extreme anthropogenic pressure; however, the broad-snouted caiman has a high adaptive capacity to colonize man-made habitats such as decanting pounds and artificial reservoirs for agriculture or livestock. In this context, the present study aimed at identifying the population structure of the broad-snouted caiman in a silvicultural landscape in southeastern Brazil. Fifty-two caimans of various classes were captured with baited traps and steel cable snares at night. The estimated population size was 51 individuals. The population density was estimated to be 2.6 individuals/ha with a linear density of 11.3 individuals/km. The intermediate values of linear density estimates herein compared with other areas, suggesting that silvicultural landscapes can be relevant for broadsnouted caiman conservation. Therefore, the role of silvicultural landscapes in crocodilian conservation should be taken into consideration for environmental certification processes related to forestry in the Neotropics.Fil: Marques, Thiago Simon. Universidade de Sao Paulo; BrasilFil: Bassetti, Luís Antonio Bochetti. Universidade de Sao Paulo; BrasilFil: Lara, Neliton Ricardo Freitas. Universidade de Sao Paulo; BrasilFil: Millan, Cristian Honora. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Piña, Carlos Ignacio. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Verdade, Luciano Martins. Universidade de Sao Paulo; Brasi

IT Outsourcing as a Source of Open Innovation

Outsourcing has been considered as an important source of innovation, nowadays. The paradigm of open innovation suggeststhat valuable ideas may occur either inside or outside the company, as in the Information Technology (IT) outsourcing. Inview of the emerging paradigm of open innovation, this paper analyzes the IT outsourcing process as an external source ofopen innovation. This research has a qualitative approach, adopting the strategy of studying multiple cases. The unit ofanalysis are three large companies, reference in their niches and aknowledged for their successful IT outsourcing practices.Results show that IT outsourcing is heavily influenced by costs reduction; however, innovation is perceived in the workingmethods resulting from the outsourcing process, being explained by the open innovation theory, since the source is external

Thermodynamic analysis of methane reforming processes and Fischer-Tropsch synthesis

Orientador: Reginaldo GuirardelloDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuímicaResumo: As reações de reforma de hidrocarbonetos leves, especialmente o gás natural, são reações químicas de elevada importância e representam etapas chave para a produção em larga escala de hidrogênio, para uso em reações de hidrogenação ou em células a combustível, ou de gás de síntese para aplicação na produção de amônia, metanol ou ainda para a síntese de Fischer-Tropsch (FT). A síntese de Fischer-Tropsch e o principal processo de conversao de hidrocarbonetos leves, como o metano, em hidrocarbonetos maiores, de maior valor agregado, assim a determinação das condições termodinamicamente favoráveis para a operação deste tipo de processos se torna cada vez mais necessária. Dentro desse contexto, as reações de reforma a vapor, reforma oxidativa, reforma autotérmica, reforma seca, reforma seca autotérmica e reforma seca combinada com reforma a vapor foram termodinamicamente avaliadas com o objetivo de determinar as melhores condições de reação para a produção de gás de síntese e de hidrogênio. Posteriormente, o gás de síntese produzido foi utilizado para a produção de metanol, etanol e hidrocarbonetos lineares, sendo avaliadas as melhores estratégias para a produção de cada um desses compostos. Para isso foram utilizadas as metodologias de minimização da energia de Gibbs a pressão e temperatura constantes e de maximização da entropia a pressão e entalpia constantes. Ambos os casos foram formulados como problemas de otimização na forma de programação não-linear, e resolvidas com o solver CONOPT2 do software GAMS 23.1'MARCA REGISTRADA'. A partir dos resultados obtidos com a aplicação da metodologia de minimização da energia de Gibbs, verificou-se que todos os processos de reforma avaliados se mostraram favoráveis para a produção de hidrogênio e/ou de gás de síntese do ponto de vista termodinâmico. Tendo a reação de reforma a vapor se destacado para a produção de hidrogênio devido a elevada razao molar H2/CO obtida no produto. A reação de oxidação parcial mostrou bons resultados para a produção de gás de síntese, devido a razão molar H2/CO próxima de 2 no produto. A comparação com dados experimentais permitiu verificar que a metodologia de minimização da energia de Gibbs apresentou boa capacidade de predição e pela comparação com dados simulados obtidos na literatura, pode-se verificar que a metodologia utilizada pelo presente trabalho esta de acordo com os dados publicados. Os resultados obtidos com a aplicação da metodologia de maximização da entropia pode-se verificar que as reações de reforma oxidativa, reforma autotérmica e reforma seca autotérmica, apresentaram comportamento autotérmico, tanto para o uso de O2 como para o uso de ar como agente oxidante. O ar mostrou capacidade de diminuir a elevação da temperatura final do sistema, sendo seu uso promissor para evitar pontos quentes no reator. A comparação com dados de perfil térmico de reatores, para as reações de reforma oxidativa e reforma autotérmica, únicas obtidas na literatura, demonstraram a boa capacidade de predição da metodologia de maximização da entropia para determinação das temperaturas de equilíbrio das reações. As analises realizadas pela aplicação da metodologia de minimização da energia de Gibbs para as reações de síntese de metanol, etanol e hidrocarbonetos lineares, demonstraram a viabilidade da produção desses compostos. Todas reações de síntese avaliadas apresentaram grande dependência da influencia do catalisador (efeito cinético) para promover a produção dos produtos de interesse. Aplicando-se a metodologia de maximização da entropia foi possível determinar que todas as reações de síntese apresentaram comportamento exotérmico. As metodologias empregadas, bem como o solver CONOPT2 aplicado no software GAMS® 23.1 se mostraram rápidos e eficazes para a solução dos problemas propostos, com baixos tempos computacionais para todos os casos analisadosAbstract: The reactions of reforming of light hydrocarbons, especially natural gas, are chemical reactions of great importance and represent key steps for large scale production of hydrogen for use in hydrogenation reactions or fuel cells, or synthesis gas production, for application in the ammonia or methanol production, or to Fischer-Tropsch (FT) synthesis. The Fischer- Tropsch synthesis is the main process of converting light hydrocarbons such as methane, in hydrocarbons of higher value added. The determination of the thermodynamically favorable conditions for the operation for this type of process is required. Within this context, the reactions of steam reforming, oxidative reforming, autothermal reforming, dry reforming, dry autothermal reforming and dry reforming combined with steam reforming were thermodynamically evaluated to determine the best reaction conditions for the production of synthesis gas and hydrogen. For this, we used the methods of Gibbs energy minimization, at constant pressure and temperature, and the Entropy maximization, at constant pressure and enthalpy. Both cases were formulated as optimization problems in the form of non-linear programming and solved with the software GAMS 2.5® with the solver CONOPT2. The results obtained by the method of minimization of Gibbs energy, for all the reform processes evaluated, proved able to produce hydrogen and syngas. Since the reaction of steam reforming showed greater ability to hydrogen production, due to high H2/CO molar ratio obtained in the product. The partial oxidation reaction showed good results for the syngas production, due to H2/CO molar ratio close to 2 in the product. The comparison with experimental data has shown that the Gibbs energy minimization method showed good predictive ability. By comparison with simulated data from the literature we can see that the methodology of minimization of Gibbs energy, used in this work is in agreement with data obtained in the literature for the same methodology. The results obtained using the methodology of entropy maximization allowed us to verify that the reactions of partial oxidation, autothermal reforming and dry autothermal reforming had autothermal behavior, both for the use of O2 as for the use of air as oxidizing agent. The air has shown ability to reduce the final temperature rise of the system, and its use has proved interesting to avoid hot spots in the reactor. A comparison with data from the reactor's thermal profile, for the reactions of partial oxidation and autothermal reforming, only found in the literature, showed good predictive ability of the methodology of entropy maximization to determine the final temperature of the reaction. The analysis realized using the methodology of Gibbs energy minimization for the synthesis reactions of methanol, ethanol and linear hydrocarbons, demonstrated the feasibility of producing these compounds. All synthesis reactions evaluated were greatly dependent on the influence of the catalyst (kinetic effect) to promote the production of products of interest. Trough the entropy maximization method was determined that all synthesis reactions analyzed presents exothermic behavior, but in the reaction conditions evaluated here, these systems can be considered safe. The methodologies used and applied in the software GAMS ® 23.1, and solved with the solver CONOPT2 proved to be fast and effective for solving the proposed problems with low computational time in all cases analyzedMestradoDesenvolvimento de Processos QuímicosMestre em Engenharia Químic