No description available.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The acerola tropical fruit and papaya are of great industrial interest for its nutritional and sensory characteristics. Due to the perishable nature of these fruits to adopt conservation methods is necessary. The present study aimed at obtaining "blends" powder from freeze-drying the pulp of acerola and papaya. First were performed compounds central rotational schedules, which evaluated the influence of lyophilization time and maltodextrin concentration and humidity on the hygroscopicity of the powders. From the results of the design were produced powders from acerola and papaya in optimal process conditions based on lower hygroscopicity, moisture was not considered by the planning because the powders obtained were within the standards established by Brazilian legislation. From the physico-chemical characterizations of the pulps and the pulps fresh powder was noticed good nutritional quality for both pulps primarily by ascorbic acid, in addition to considerable amounts of anthocyanins and carotenoids in relation to adsorption isotherms both the powders exhibited type III curves concave-shaped "J" typically associated with the food powders from fruit, yet papaya pulp powder showed reversal of the effect of temperature on adsorption capacity for water a range of water activity of 0,8. The Oswin model was the best fit curves for the prediction of the pulp powder at all temperatures analyzed for papaya pulp, the model proposed by BET was the best fit the data. Then experiment was conducted mixtures simplex centroid increased to three components (acerola pulp, papaya pulp and maltodextrin) to obtain the "blend" lyophilized powder, by determining the effect of the proportions of the mixture on the hygroscopicity , solubility, time and degree of rehydration Caking. The time lyophilization of "blends" was the simple arithmetic average between the times of lyophilization obtained by central composite design for the pulp powder acerola and papaya. The results of qualitative analysis of the mixture enabled the choice of test 6 with the proportions 25% acerola pulp, 50% papaya pulp and 25% maltodextrin as best assay for production of "blend" powder. The "blend" powder obtained under optimum conditions showed good physicochemical characteristics, in relation to sorption isotherms, the GAB model was the best fit the experimental data, where the curves were type III. Then there was the study of the stability of the "blend" powder in storage period of 20 days packed in polyethylene wrapped in aluminum foil. Thus, it was concluded that, after this storage period, the "blend" powder, the patient was still in powder form and has good chemical-physical characteristics and hygroscopic. / A acerola e mamÃo sÃo frutos tropicais de grande interesse industrial por suas caracterÃsticas nutricionais e sensoriais. Em virtude do carÃter perecÃvel desses frutos a adoÃÃo de mÃtodos de conservaÃÃo faz-se necessÃria. O presente trabalho teve como objetivo obter âblendsâ em pà a partir da liofilizaÃÃo das polpas de acerola e mamÃo. Primeiramente foram realizados planejamentos compostos central rotacionais, onde se avaliou a influÃncia do tempo de liofilizaÃÃo e concentraÃÃo de maltodextrina sobre a higroscopicidade e umidade dos pÃs obtidos. A partir dos resultados do planejamento foram produzidos os pÃs de acerola e mamÃo em condiÃÃes Ãtimas, baseadas na menor higroscopicidade. A umidade nÃo foi considerada pelo planejamento, pois os pÃs encontravam-se dentro do especificado pela legislaÃÃo brasileira. A partir das caracterizaÃÃes fÃsico-quÃmicas das polpas in natura e das polpas em pà percebeu-se boa qualidade nutricional para ambas as polpas principalmente pelo teor de Ãcido ascÃrbico, alÃm de considerÃveis teores de antocianinas e carotenÃides, em relaÃÃo Ãs isotermas de adsorÃÃo, ambos os pÃs apresentaram curvas do tipo III, cÃncavas em formato de âJâ, tipicamente associado a pÃs a base de frutos, contudo a polpa de mamÃo em pà apresentou inversÃo do efeito da temperatura sobre a capacidade de adsorÃÃo da Ãgua em uma faixa de atividade de Ãgua de 0,75. O modelo de Oswin foi o que melhor se ajustou na prediÃÃo das curvas para polpa de acerola em pà nas temperaturas analisadas. Para a polpa de mamÃo, o modelo proposto por BET foi o que melhor se ajustou aos dados. Em seguida realizou-se delineamento experimental de misturas simplex centrÃide aumentado para 3 componentes (polpa de acerola; polpa de mamÃo e maltodextrina) para obter-se âblendâ em pà liofilizado, atravÃs da determinaÃÃo do efeito das proporÃÃes da mistura sobre a higroscopicidade, solubilidade, tempo de reidrataÃÃo e grau de Caking. O tempo de liofilizaÃÃo dos âblendsâ foi à mÃdia aritmÃtica simples entre os tempos de liofilizaÃÃo obtidos pelo planejamento composto central para as polpas em pà de acerola e mamÃo. Os resultados da anÃlise qualitativa da mistura possibilitou a escolha do ensaio 6 com as proporÃÃes 25% de polpa de acerola, 50% de polpa de mamÃo e 25% de maltodextrina como melhor ensaio para produÃÃo do âblendâ em pÃ. O âblendâ em pà nas condiÃÃes Ãtimas apresentou boas caracterÃsticas fÃsico-quÃmicas, em relaÃÃo Ãs isotermas de sorÃÃo, o modelo de GAB foi o que melhor se ajustou aos dados experimentais, onde as curvas foram do tipo III. Em seguida, realizou-se o estudo da estabilidade do âblendâ em pÃ, pelo perÃodo de 20 dias acondicionados em embalagem de polietileno envolvidos em folha de alumÃnio. Com isso, concluiu-se que, apÃs este perÃodo de armazenamento, o âblendâ em pÃ, ainda apresentava-se na forma de pà e com boas caracterÃsticas fÃsico-quÃmicas e higroscÃpicas.

ARAÚJO, Silas Rafael Figueiredo de. Elaboração de misturas em pó das polpas de acerola e mamão. 2013. 94 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2013 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-27T13:50:00Z No. of bitstreams: 1 2013_dis_srfaraujo.pdf: 1328981 bytes, checksum: a1d64e44159439697ef9305f76bdd5f0 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-27T13:50:18Z (GMT) No. of bitstreams: 1 2013_dis_srfaraujo.pdf: 1328981 bytes, checksum: a1d64e44159439697ef9305f76bdd5f0 (MD5) / Made available in DSpace on 2016-06-27T13:50:18Z (GMT). No. of bitstreams: 1 2013_dis_srfaraujo.pdf: 1328981 bytes, checksum: a1d64e44159439697ef9305f76bdd5f0 (MD5) Previous issue date: 2013 / The acerola tropical fruit and papaya are of great industrial interest for its nutritional and sensory characteristics. Due to the perishable nature of these fruits to adopt conservation methods is necessary. The present study aimed at obtaining "blends" powder from freeze-drying the pulp of acerola and papaya. First were performed compounds central rotational schedules, which evaluated the influence of lyophilization time and maltodextrin concentration and humidity on the hygroscopicity of the powders. From the results of the design were produced powders from acerola and papaya in optimal process conditions based on lower hygroscopicity, moisture was not considered by the planning because the powders obtained were within the standards established by Brazilian legislation. From the physico-chemical characterizations of the pulps and the pulps fresh powder was noticed good nutritional quality for both pulps primarily by ascorbic acid, in addition to considerable amounts of anthocyanins and carotenoids in relation to adsorption isotherms both the powders exhibited type III curves concave-shaped "J" typically associated with the food powders from fruit, yet papaya pulp powder showed reversal of the effect of temperature on adsorption capacity for water a range of water activity of 0,8. The Oswin model was the best fit curves for the prediction of the pulp powder at all temperatures analyzed for papaya pulp, the model proposed by BET was the best fit the data. Then experiment was conducted mixtures simplex centroid increased to three components (acerola pulp, papaya pulp and maltodextrin) to obtain the "blend" lyophilized powder, by determining the effect of the proportions of the mixture on the hygroscopicity , solubility, time and degree of rehydration Caking. The time lyophilization of "blends" was the simple arithmetic average between the times of lyophilization obtained by central composite design for the pulp powder acerola and papaya. The results of qualitative analysis of the mixture enabled the choice of test 6 with the proportions 25% acerola pulp, 50% papaya pulp and 25% maltodextrin as best assay for production of "blend" powder. The "blend" powder obtained under optimum conditions showed good physicochemical characteristics, in relation to sorption isotherms, the GAB model was the best fit the experimental data, where the curves were type III. Then there was the study of the stability of the "blend" powder in storage period of 20 days packed in polyethylene wrapped in aluminum foil. Thus, it was concluded that, after this storage period, the "blend" powder, the patient was still in powder form and has good chemical-physical characteristics and hygroscopic. / A acerola e mamão são frutos tropicais de grande interesse industrial por suas características nutricionais e sensoriais. Em virtude do caráter perecível desses frutos a adoção de métodos de conservação faz-se necessária. O presente trabalho teve como objetivo obter “blends” em pó a partir da liofilização das polpas de acerola e mamão. Primeiramente foram realizados planejamentos compostos central rotacionais, onde se avaliou a influência do tempo de liofilização e concentração de maltodextrina sobre a higroscopicidade e umidade dos pós obtidos. A partir dos resultados do planejamento foram produzidos os pós de acerola e mamão em condições ótimas, baseadas na menor higroscopicidade. A umidade não foi considerada pelo planejamento, pois os pós encontravam-se dentro do especificado pela legislação brasileira. A partir das caracterizações físico-químicas das polpas in natura e das polpas em pó percebeu-se boa qualidade nutricional para ambas as polpas principalmente pelo teor de ácido ascórbico, além de consideráveis teores de antocianinas e carotenóides, em relação às isotermas de adsorção, ambos os pós apresentaram curvas do tipo III, côncavas em formato de “J”, tipicamente associado a pós a base de frutos, contudo a polpa de mamão em pó apresentou inversão do efeito da temperatura sobre a capacidade de adsorção da água em uma faixa de atividade de água de 0,75. O modelo de Oswin foi o que melhor se ajustou na predição das curvas para polpa de acerola em pó nas temperaturas analisadas. Para a polpa de mamão, o modelo proposto por BET foi o que melhor se ajustou aos dados. Em seguida realizou-se delineamento experimental de misturas simplex centróide aumentado para 3 componentes (polpa de acerola; polpa de mamão e maltodextrina) para obter-se “blend” em pó liofilizado, através da determinação do efeito das proporções da mistura sobre a higroscopicidade, solubilidade, tempo de reidratação e grau de Caking. O tempo de liofilização dos “blends” foi à média aritmética simples entre os tempos de liofilização obtidos pelo planejamento composto central para as polpas em pó de acerola e mamão. Os resultados da análise qualitativa da mistura possibilitou a escolha do ensaio 6 com as proporções 25% de polpa de acerola, 50% de polpa de mamão e 25% de maltodextrina como melhor ensaio para produção do “blend” em pó. O “blend” em pó nas condições ótimas apresentou boas características físico-químicas, em relação às isotermas de sorção, o modelo de GAB foi o que melhor se ajustou aos dados experimentais, onde as curvas foram do tipo III. Em seguida, realizou-se o estudo da estabilidade do “blend” em pó, pelo período de 20 dias acondicionados em embalagem de polietileno envolvidos em folha de alumínio. Com isso, concluiu-se que, após este período de armazenamento, o “blend” em pó, ainda apresentava-se na forma de pó e com boas características físico-químicas e higroscópicas.

The objective of this thesis is to experimentally investigate the performance of steam gasification of chars of pure coal (lignite, sub-bituminous), pure biomass (radiata pine, eucalyptus nitens) and their blends. The influences of gasification temperature, types of coal and biomass, coal-biomass blending ratio, alkali and alkaline earth metal (AAEM) in lignite, on specific gasification characteristics (producer gas composition and yield, char reactivity) were studied. In addition, synergistic effects in co-gasification of coal-biomass blend char were also investigated. This project is in accordance with objectives of the BISGAS Consortium. In this study, experiments were performed in a bench-scale gasifier at gasification temperatures of 850°C, 900°C and 950°C, respectively. Two types of coals (lignite and sub-bituminous) and two kinds of biomass (radiata pine and eucalyptus nitens) from New Zealand were selected as sample fuels. From these raw materials, the chars with coal-to-biomass blending ratios of 0:100 (pure coal), 20:80, 50:50, 80:20 and 100:0 (pure biomass), which were derived through the devolatilization at temperature of 900°C for 7 minutes, were gasified with steam as gasification agent. During the gasification tests, the producer gas composition and gas production were continuously analysed using a Micro gas chromatograph. When the gas production was undetectable, the gasification process was assumed to be completed and the gasification time was recorded. The gasification producer gas consisted of three main gas components: hydrogen (H2), carbon monoxide (CO) and carbon dioxide (CO2). The results from gasification of chars of individual solid fuels (coal or biomass) confirmed that biomass char gasification was faster than coal char gasification. The influences of gasification temperatures were shown as: when gasification temperature increased, the H2 yield increased in coal char gasification but decreased in biomass char gasification. In the meantime, CO yields increased while CO2 yields decreased in both coal char and biomass char gasification. In addition, the char reactivity of all the pure fuel samples increased with elevated gasification temperatures. The results from co-gasification of coal-biomass blend char exhibited that the syngas production rate, which is defined as the total gas production divided by the gasification completion time, was enhanced by an increase in gasification temperatures as well as an increase in the biomass proportion in the blend. The AAEM species played a significant catalytic role in both gasification of pure coal chars and co-gasification of coal-biomass blend chars. The presence of AAEM increased the producer gas yield and enhanced the char reactivity. The positive synergistic effects of the coal-biomass blending char on syngas production rate only existed in the co-gasification of lignite-eucalyptus nitens blend chars. The other blend chars showed either insignificant synergistic effects or negative effects on the syngas production rate.

No description available.

There is a need for a systematic collection of ideas concerning blend in choral sound. Many authorities discuss blend, but their concepts of the term are very divergent. These divergent concepts lead to emphasis of various factors which are important to the development or achievement of blend in choral sound. This emphasis in turn leads to various methods of achieving blend. Authorities ascribe several definitions to the term blend, as it relates to choral tone. These definitions should be studied collectively in order that a clearer concept of the term blend in choral sound may be developed. In studying blend in choral sound, several factors are generally deemed important. No study has been made which leads to a consensus concerning the relative importance of these factors. Scientific studies have been made of these factors, but the results have not been compiled and presented in one source. Authorities employ various methods in working with the factors which affect blend in choral sound. No study has been made which includes these methods. It is hoped that this study will contribute to the collecting and organizing of ideas regarding blend, including its various definitions and its important factors. It is also hoped that this study will contribute to the understanding of these factors as they relate to the achievement of blend in choral sound. It is intended that this study will present this information in such a manner as to be of assistance to the musician in the field of choral music.

The Drosophila larva is a suitable model to study olfaction due to its numerical simplicity. The peripheral olfactory system consists of just 21 pairs of olfactory sensory neurons (OSNs), each expressing one, or at most two classes of olfactory receptors (ORs) that define the receptive range of the OSN. Larvae produce robust behaviours to many odours and are easily genetically manipulated. Unlike audition, relatively little is known regarding olfaction due to its complex nature - most odours exist as multimolecular units that vary in their identity and structure, concentrations and proportions. Until recently, most olfactory research has focused on the processing of simple odours, which does not realistically model real-world odours. Presented here is one of the first in situ investigations of odour mixture processing in the Drosophila melanogaster larva. Processing of odour mixtures was explored using both electrophysiological recordings of the peripheral olfactory system and behavioural assays at the output of the system, and the effects of various factors on responses were also explored. w1118 larvae in which all OSNs were functional, and larvae with only a single class of OSN (using the Gal4-UAS expression system) were studied. At the peripheral level, mixture responses were never entirely transformed from the components, and were always as large as or greater than the response to the strongest component, and therefore the neuron was either 'seeing' just one or more than one of the components, respectively. Mixture responses across all OSNs were always additive, hypoadditive or partially suppressive, and there were no instances of synergistic or fully suppressive responses. Peripheral mixture responses were both OR- and component-dependent, as the same mixture was represented differently across OSNs. At the behavioural level, mixture responses were mostly additive, partially and fully suppressive and therefore not always predictable from the components. Interestingly, responses of larvae with only a single class of OSN were mostly predictable as there was no complexity of processing arising from the combinatorial code. When all OSNs were functional and the combinatorial code appropriately activated, mixture responses were more complex and unpredictable. Associative conditioning experiments revealed that larvae were unable to identify components from within a mixture, providing evidence that, at least at the behavioural level, mixture responses were probably synthetic, and therefore likely that interactions between the components occurred at some point along the processing pathway. Mixtures were often dominated by the component inducing the largest firing rate, and carbon chain length and vapour pressure influenced, to some degree, which component dominated. The nature of mixture responses were affected by concentration which is consistent with a model of receptor competition - at low concentrations mixture responses were additive, whilst at high concentrations responses were reduced compared to an additive response. In contrast, prior experience had little effect on peripheral responses to pure odours and mixtures, although rapid adaptation was observed during exposure. Exposure did have an effect on subsequent behavioural responses to pure odours and mixtures, providing evidence of central effects of adaptation. The data presented here provides evidence that mixture processing is extremely complex, with many factors influencing and affecting the way that the system responds to mixtures. This data reveals an unexpected complexity in a numerically simple system and with such'simple' complex odours, and indicates the likelihood of more complex responses when all OSNs are functional.

Differential scanning calorimetry (DSC), 13C solid state nuclear magnetic resonance (SSNMR), one- and two-dimensional fourier transform infrared spectroscopes (FT-IR), Gel Permeation Chromatography (GPC) have been used to investigate the miscibility behavior and specific interactions of Poly(3-hydroxybutyrate), (PHB) blending with poly(styrene-co-vinyl phenol), (PS-co-PVPh) through hydrogen bonding complex upon varying the vinyl phenol contents in copolymer. We describe FT-IR spectra reveal that hydrogen bonding between carbonyl and phenol. A miscibility window exists when the vinyl phenol fraction in the copolymer is greater than 20 mol% in the PHB/PS-co-PVPh blend system, as predicted using the Painter¡VColeman association model. The vinyl-terminated benzoxazine (VB-a), which can be polymerized through ring opening polymerization, was synthesized through the Mannich condensation of bisphenol A, formaldehyde, and allylamine. This VB-a monomer was then blending with epoxy resin, followed by thermal curing concurrently, to form epoxy/VB-a copolymers network. To understand the curing kinetics of this epoxy/VB-a copolymer, dynamic differential scanning calorimetry measurements were performed by Kissinger and Flynn-Wall-Osawa methods. The FTIR analyses revealed the presence of thermal curing reactions and hydrogen bonding interaction of epoxy/VB-a copolymers. Meanwhile, the significant enhancement of the ring opening and allyl polymerizations of the epoxy was observed. For these IPNs, DMA and TGA results indicate that the thermal properties increase with the increase of VB-a contents in epoxy/VB-a copolymers.

Konstanz, Univ., Diss., 2000.

Universiẗat, Diss., 2001--Freiburg (Breisgau).