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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Oxygen Transport Measured by Isotope Tracing through Solid Oxides

Wood, Thomas 31 May 2011 (has links)
The following thesis demonstrates two isotope tracing experiments that measure oxygen transport through electrochemically polarized solid oxides. Cathode-symmetric ‘button’ cells with yttria stabilized zirconia(YSZ) electrolytes and either strontium doped lanthanum manganate(LSM) or composite LSM/YSZ cathodes were studied. The first experiment measured the residence time distributions(RTD) of 34O2. The measured RTDs were compared at different temperatures(700-800°C) and applied potentials(-2 to -8V). Comparisons with simulated RTDs revealed that oxygen transport was laterally heterogeneous. Delamination of the counter electrode is likely the source of the heterogeneity. The second experiment measured a wave of 18O by exposing an interior cross section and applying ToF-SIMS analysis. A depth profile was produced that spans the cathode and electrolyte interface. The depth profile was compared with a variety of limiting oxygen activation scenarios predicted by a simple 1-D model. Comparisons demonstrated that oxygen activation is likely not restricted to the cathode and electrolyte interface.
112

Oxygen Transport Measured by Isotope Tracing through Solid Oxides

Wood, Thomas 31 May 2011 (has links)
The following thesis demonstrates two isotope tracing experiments that measure oxygen transport through electrochemically polarized solid oxides. Cathode-symmetric ‘button’ cells with yttria stabilized zirconia(YSZ) electrolytes and either strontium doped lanthanum manganate(LSM) or composite LSM/YSZ cathodes were studied. The first experiment measured the residence time distributions(RTD) of 34O2. The measured RTDs were compared at different temperatures(700-800°C) and applied potentials(-2 to -8V). Comparisons with simulated RTDs revealed that oxygen transport was laterally heterogeneous. Delamination of the counter electrode is likely the source of the heterogeneity. The second experiment measured a wave of 18O by exposing an interior cross section and applying ToF-SIMS analysis. A depth profile was produced that spans the cathode and electrolyte interface. The depth profile was compared with a variety of limiting oxygen activation scenarios predicted by a simple 1-D model. Comparisons demonstrated that oxygen activation is likely not restricted to the cathode and electrolyte interface.
113

Biology of tooth wear: preventive strategies.

Ranjitkar, Sarbin January 2010 (has links)
There is an increasing awareness in clinical dentistry of the need to better understand the aetiology and management of tooth wear, as increasing numbers of elderly patients are retaining their natural teeth to a stage when they present with extensive wear. In addition, more younger patients are presenting with wear of both primary and permanent teeth. In order to comply with the philosophy of minimal intervention dentistry, clinical management of tooth wear should focus on early detection and prevention before a restorative approach is considered. Fluoride is a commonly used agent in the management of tooth wear, with previous studies showing that it can protect teeth against erosion (at around pH 2.0 and 3.0) and toothbrush abrasion in an acidic environment (at around pH 3.0). However, it does not reduce attritional wear between opposing tooth specimens. Nightguards are commonly used to prevent attritional wear but there is still a need to improve preventive strategies to manage the risk of erosive tooth wear. Previous in vitro studies have shown that a remineralizing agent in the form of CPP-ACP (casein phosphopeptide – amorphous calcium phosphate) can reduce erosion of both enamel and dentine by white wine. A recent study has also highlighted the potential lubricating and remineralizing properties of a CPP-ACP containing paste (Tooth Mousse®, G C Asia Pty Ltd) in reducing dentine wear in both an acidic environment (pH 3.0) and a near neutral environment (pH 6.1). In this context, it is desirable to investigate the effect of CPP-ACP on enamel wear under conditions simulating various clinical situations and to better understand the nature of third-body components at the wear interface. The aims of the present study were: (i) to determine the effect of CPP-ACP on enamel wear under conditions simulating three clinical situations: heavy attrition with gastric regurgitation (at pH 1.2); toothbrush abrasion after an erosive episode (at pH 3.2); and erosion from gastric regurgitation (at pH 1.2), and (ii) to clarify its mode of action by characterizing the enamel surface treated with CPP-ACP. Electro-mechanical tooth wear machines were used to simulate attrition and toothbrush abrasion in combination with erosion, but no machine was used in experiments investigation erosion alone. The effect of paste containing CPP-ACP in reducing erosive tooth wear was also compared with that without CPP-ACP. Enamel surfaces with and without treatment with CPP-ACP were then characterized by using Time of Flight – Secondary Ion Mass Spectrometry (ToF-SIMS). CPP-ACP was found to reduce enamel wear under conditions simulating heavy attrition combined with gastric regurgitation, and toothbrush abrasion after an erosive episode. However, it did not protect enamel from erosion under conditions simulating gastric regurgitation alone, indicating that its lubricating effect was more pronounced than its remineralizing effect. Silicone and ethyl siloxane were present in trace amounts on the enamel surface treated with Tooth Mousse®, thus they were found to be included in its formulation. These findings imply that CPP-ACP nanocomplexes and silicon can act as third body components to lubricate the wear interface. The findings presented in this thesis have implications for clinical management of tooth wear and may lead to new strategies of tooth wear prevention. Although some caution is needed in extrapolating these findings to the in vivo situation, it should be noted that in vitro studies provide valuable insights into separate components of the tooth wear process that are often difficult to distinguish in clinical situations. Overall, this thesis provides new information about the role of CPP-ACP in reducing erosive enamel wear and provides a basis for future experimental and clinical studies focussing on tooth wear prevention. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1379897 / Thesis (Ph.D.) -- University of Adelaide, School of Dentistry, 2009
114

Electrochemistry of Cathode Materials in Aqueous Lithium Hydroxide Electrolyte

minakshi@murdoch.edu.au, Manickam Minakshi Sundaram January 2006 (has links)
Electrochemical behavior of electrolytic manganese dioxide (EMD), chemically prepared battery grade manganese dioxide (BGM), titanium dioxide (TiO2), lithium iron phosphate (LiFePO4) and lithium manganese phosphate (LiMnPO4) in aqueous lithium hydroxide electrolyte has been investigated. These materials are commonly used as cathodes in non-aqueous electrolyte lithium batteries. The main aim of the work was to determine how the electroreduction/oxidation behavior of these materials in aqueous LiOH compares with that reported in the literature in non-aqueous electrolytes in connection with lithium batteries. An objective was to establish whether these materials could also be used to develop other battery systems using aqueous LiOH as electrolyte. The electrochemical characteristics of the above materials were investigated by subjecting them to slow scan cyclic voltammetry and determining the charge/discharge characteristics of Zn/cathode material-aqueous LiOH batteries. The products of electroreduction/oxidation were characterized by physical techniques using X-ray diffraction (XRD), scanning electron micrography (SEM), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), Thermogravimetric analysis (TG) and infra-red spectrometry (IR). The reduction of ã-MnO2 (EMD) in aqueous lithium hydroxide electrolyte is found to result in intercalation of Li+ into the host structure of ã-MnO2. The process was found to be reversible for many cycles. This is similar to what is known to occur for ã-MnO2 in non-aqueous electrolytes. The mechanism, however, differs from that for reduction/oxidation of ã-MnO2 in aqueous potassium hydroxide electrolyte. KOH electrolyte is used in the state-of-art aqueous alkaline Zn/MnO2 batteries. Alkaline batteries based on aqueous KOH as the electrolyte rely upon a mechanism other than K+ intercalation into MnO2. This mechanism is not reversible. This is explained in terms of the relative ionic sizes of Li+ and K+. The lithium-intercalated MnO2 lattice is stable because Li+ and Mn4+ are of approximately the same size and hence Li+ is accommodated nicely into the host lattice of MnO2. The K+ ion which has almost double the size of Li+ cannot be appropriately accommodated into the host structure and hence the K+ -intercalated MnO2 phase is not stable. Chemically prepared battery grade MnO2 (BGM) is found to undergo electroreduction/oxidation in aqueous LiOH via the same Li+ intercalation mechanism as for the EMD. While the Zn/BGM- aqueous LiOH cell discharges at a voltage higher than that for the Zn/EMD- aqueous LiOH cell under similar conditions, the rechargeability and the material utilization of the BGM cell is poorer. The cathodic behavior of TiO2 (anatase phase) in the presence of aqueous LiOH is not reversible. In addition to LiTiO2, Ti2O3 is also formed. The discharge voltage of the Zn/TiO2- aqueous LiOH cell and material utilization of the TiO2 as cathode are very low. Hence TiO2 is not suitable for use in any aqueous LiOH electrolyte battery. LiFePO4 (olivine-type structure) as a cathode undergoes electrooxidation in aqueous LiOH forming FePO4. However the subsequent reduction forms not only the original LiFePO4 but also Fe3O4. Thus the process is not completely reversible and hence LiFePO4 is not a suitable material for use as a cathode in aqueous battery systems. LiMnPO4 (olivine-type structure) undergoes reversible electrooxidation in aqueous LiOH forming MnPO4. The charge/discharge voltage profile of the Zn/MnPO4-aqueous LiOH cell, its coulombic efficiency and rechargeability are comparable to that of the cell using ã-MnO2. EMD and LiMnPO4 both have the potential for use in rechargeable batteries using aqueous LiOH as the electrolyte. Recommendations for further developmental work for such batteries are made.
115

Investigating the female detective : gender paradoxes in popular British mystery fiction, 1864-1930 /

Dzirkalis, Anna M. January 2007 (has links)
Thesis (Ph.D.)--Ohio University, June, 2007. / Includes bibliographical references (leaves 338-348)
116

The Sims-Daniels naval dispute, 1919-1920

Roberts, John E., January 1966 (has links)
Thesis (M.A.)--University of Wisconsin--Madison, 1966. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
117

Manejo de água e potassio por fertirrigação no maracujazeiro amarelo em alvorada do gurguéia, Piauí / Irrigation and potassium scheduling applied through fertirrigation of yellow passion fruits in the municipality of Alvorada do Gurguéia, Piauí

Vasconcelos, Denise Vieira January 2007 (has links)
VASCONCELOS, Denise Vieira. Manejo de água e potassio por fertirrigação no maracujazeiro amarelo em alvorada do gurguéia, Piauí. 2007. 66 f. Dissertação (Mestrado em engenharia agrícola)- Universidade Federal do Ceará, Fortaleza-CE, 2007. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-06-17T17:57:46Z No. of bitstreams: 1 2007_dis_dvvasconcelos.pdf: 2270341 bytes, checksum: e29aea1e2937644f7b4c3462b5fdb1e6 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-07-21T20:08:37Z (GMT) No. of bitstreams: 1 2007_dis_dvvasconcelos.pdf: 2270341 bytes, checksum: e29aea1e2937644f7b4c3462b5fdb1e6 (MD5) / Made available in DSpace on 2016-07-21T20:08:37Z (GMT). No. of bitstreams: 1 2007_dis_dvvasconcelos.pdf: 2270341 bytes, checksum: e29aea1e2937644f7b4c3462b5fdb1e6 (MD5) Previous issue date: 2007 / This work aimed to study the effects of five layers of irrigation and five doses of potassium – applied through fertirrigation – on productivity and on quality of yellow passion fruits, in order to provide a proper crop management. The experiments were conducted on Embrapa Meio-Norte experimental field, in the municipality of Alvorada do Gurgueia, PI, Brazil, from March 2004 through April 2006. The experimental design consisted of randomized blocks with design in split-plots, with four replications. The treatments consisted of five doses of potassium (0,000; 0,225; 0,450; 0,650; 0,900 kg of K2O plant-1) and five irrigation layers (30; 60; 90; 120 and 150% of ECA). The plants were spaced by 2.5m x 4.0m. The results show that productivity and mean weight of fruits were significantly affected by irrigation layers, doses of potassium, as well as by the interaction term between the two factors; as for the number of fruits per hectare was significantly affected only by doses of potassium. Regarding the physical characteristics of the fruits, the longitudinal diameter and the juice production were significantly affected by number of layers, doses of potassium, and by the interaction term. The thickness of the rind was affected only by doses of potassium. As for the chemical characteristics of the fruits, only the level of total soluble solids was significantly affected by number of layers, doses, and by the interaction term; tritable total acidity (ATT) was affected only by doses of potassium; and pH was affected by none of the factors considered in this study. Among all treatment combinations, L4K4 yielded the highest fruit productivity, number, and mean weight. The levels of total soluble solids decreased with the increase layers applied, and the total acidity increased linearly with the increase of doses of potassium. / O trabalho teve como objetivo estudar o efeito de cinco lâminas de irrigação e cinco doses de potássio, aplicados via fertirrigação, na produtividade e nas qualidades dos frutos do maracujazeiro amarelo, para posteriormente definir um manejo adequado da cultura. O experimento foi realizado no campo experimental da Embrapa Meio-Norte, no município de Alvorada do Gurguéia-PI, no período de março de 2004 a abril de 2006, sendo que o delineamento utilizado foi em blocos casualizados com arranjo em parcelas subdivididas, com quatro repetições. Os tratamentos foram compostos por cinco doses de potássio (0,000; 0,225; 0,450; 0,650; 0,900 kg de K2O planta-1) e cinco lâminas de irrigação (30; 60; 90; 120 e 150% da ECA). As plantas foram espaçadas de 2,5 x 4,0 m. Verificou-se que a produtividade e o peso médio dos frutos foram influenciados significativamente pelas lâminas de irrigação, pelas doses de potássio e pela interação entre os fatores; já o número de frutos por hectare somente foi influenciado significativamente pelas doses de potássio. Para as características físicas dos frutos, somente o diâmetro longitudinal e o rendimento do suco sofreram influência significativa da lâmina, das doses de potássio e da interação entre os fatores. A espessura da casca só foi influenciada pelas doses de potássio. Nas características químicas dos frutos observou-se que, somente o teor de sólidos solúveis totais sofreu influência das lâminas, das doses de potássio e da interação entre os dois fatores; a acidez total titulável foi influenciada apenas pelas doses de potássio e o pH, não foi influenciado por nenhum dos fatores estudados. A combinação dos tratamentos L4K4 foi a que proporcionou maior produtividade, número e peso médio dos frutos. Os teores de sólidos solúveis totais diminuíram com o aumento da lâmina aplicada e a acidez total titulável cresceu linearmente com as doses de potássio.
118

Coeficiente de cultivo e lâminas de irrigação do Maracujazeiro Amarelo nas condições semiáridas / Coefficient of cultivation and irrigation of yellow passion fruit in semiarid conditions

Nogueira, Eliomar January 2011 (has links)
NOGUEIRA, Eliomar. Coeficiente de cultivo e lâminas de irrigação do Maracujazeiro Amarelo nas condições semiáridas. 2011. 71 f. Dissertação (Mestrado em engenharia agrícola)- Universidade Federal do Ceará, Fortaleza-CE, 2011. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-06-17T19:27:24Z No. of bitstreams: 1 2011_dis_enogueira.pdf: 6330872 bytes, checksum: b45642fa70c9e615f28157c7d80c869a (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-07-21T20:12:01Z (GMT) No. of bitstreams: 1 2011_dis_enogueira.pdf: 6330872 bytes, checksum: b45642fa70c9e615f28157c7d80c869a (MD5) / Made available in DSpace on 2016-07-21T20:12:01Z (GMT). No. of bitstreams: 1 2011_dis_enogueira.pdf: 6330872 bytes, checksum: b45642fa70c9e615f28157c7d80c869a (MD5) Previous issue date: 2011 / This work aims to determine the crop coefficie nt of the yellow passion fruit and to find irrigation levels that can raise the yield a nd quality of passion fruit production under the environmental conditions of the semiarid re gion of Piaui (Br). The experiment was conducted at the Projeto Piloto de Fruticultura Irrigada (Irrigated Fruit Culture Pilot Project) of the CODEVASF, in Santa Rosa, PI (06 ° 47 '5 6''S, 42 ° 17' 17''W). We used randomized blocks with six treatments and four replications, with four plants to a plot. The treatments (irrigation levels) were defined as percentages of the reference evapotranspiration (ETo): T1 (25% ETo), T2 (50% ETo), T3 (75% ETo), T4 ( 1 00% ETo), T5 (125% ETo) and T6 (150% ETo). It was installed a battery with three tensiom eters per treatment at depths of 0.10 m, 0.30 m and 0.50 m, to monitor the soil water. Determining the crop coefficient (Kc), we used the soil water balance, and for obtaining that, two batteries were installed, with tensiometers placed at depths of 0.10 m, 0.30 m 0.50 m within a radius of 0.30 m and 0.60 m from the stems of the plants in T4. The Kc values were estimated in the 41-240 days a fter transplanting (DAT). The irrigation le vels of 408.25 mm (T1), 463.41 mm (T2) 535.11 mm (T3), 609.98 mm (T4), 704.71 mm (T5) and 826.02 mm (T6) were applied on performing the experiment. We evaluated the morphological and physiologic al growth variables of yellow passion fruit (plant height, stem diameter, number of internod es, leaf area, leaf number and leaf water potential) and production traits (yield, fruit numb er, fruit weight, fruit transverse diameter and fruit longitudinal diameter). Analysis of varia nce showed that the irrigation significantly influenced stem diameter (P <0.05) in assessments conducted in December 2009, January and February 2010; leaf area (P < 0.01) for assessments conducted from Januar y to April 2010; number of leaves (P <0.05) for assessments conducted in March 2010 and (P <0.01) in April 2010; leaf water potential (P <0.01) at all testing times. Besides, the number of fruits (P<0.05), the average fruit weight (P <0.05) and the productivity (P <0.05) were found significantly responding to the irrigation level. Maximum yield (6763 kg ha-1) was obtained in 60 days of harvest, ie 25% of potential annual production of passion fruit was obtained with an irrigation level of 763.80 mm...Estimating to its full potential to the first year of production we obtained a value of 27,052 kg ha-1 yr -1. As for the average fruit weight, it ranged from 0.207 kg (T6) to 0,159 kg (T1). The maximum number of fruits (33 119 fruit ha -1) was obtained with an irrigation level of 760.21 mm. The Kc values ranged from 0.43 to 1.04 with a maximum recorded value at 211 to 220 DAT. The average Kc obtained at the vegetative stage, was 0.57, and the average Kc at the production stage(flower ing and fruiting)was 0.94. Therefore: The irrigation level most suitable for the passion fruit must be between 72% and 100% ETo; The assessed morphophysiological growth variables of the yellow passion fruit are influenced by the variation of irrigation level applied to culture; The yield, average weight and fruit number of the yellow pa ssion plant are also influenced by the same variation of irrigation level. / NOGUEIRA, Eliomar, Universidade Federal do Ceará. Fevereiro de 2011. Coeficiente de cultivo e lâminas de irrigação do maracujazeiro amarelo nas condições semiáridas. Orientador: Valdemício Ferreira de Sousa. Conselheiros: Thales Vinícius de Araújo Viana, Luís de França Camboim Neto. O objetivo do trabalho foi determinar o coeficiente de cultivo do maracujazeiro amarelo e definir lâminas de irrigação capazes de elevar a produtividade da cultura e a qualidade da produção nas condições ambientais da região semiárida do Piauí. O experimento foi realizado na área do Projeto Piloto de Fruticultura Irrigada da CODEVASF, no município de Santa Rosa, PI (06° 47’ 56’’ S, 42° 17’ 17’’ W). Utilizou-se delineamento experimental blocos ao acaso com seis tratamentos e quatro repetições, parcela com quatro plantas úteis. Os tratamentos (lâminas de irrigação) foram definidos em função de percentagens da evapotranspiração de referência (ETo): T1 (0,25*ETo), T2 (0,50*ETo), T3 (0,75*ETo), T4 (1,00*ETo), T5 (1,25*ETo) e T6 (1,50*ETo). Para o monitoramento da água no perfil do solo instalou-se uma bateria com três tensiômetros por tratamento nas profundidades de 0,10 m; 0,30 m e 0,50 m. Para determinação do coeficiente de cultivo (Kc), utilizou-se o balanço de água no solo e para tanto, foram instaladas duas baterias com tensiômetros distribuídos nas profundidades de 0,10 m; 0,30 m e 0,50 m, num raio de 0,30 m e 0,60 m do caule das plantas no T4 . No período de 41-240 dias após transplantio (DAT) estimou-se valores de Kc. Na execução do experimento foram aplicadas as respectivas lâminas de irrigação 408,25 mm (T1), 463,41 mm (T2), 535,11 mm (T3), 609,98 mm (T4), 704,71 mm (T5) e 826,02 mm (T6). Foram avaliadas as características morfofisiológicas de crescimento do maracujazeiro amarelo (altura da planta, diâmetro do caule, número de internós, área foliar, número de folhas e potencial hídrico foliar; características de produção (produtividade, números de frutos, peso médio de frutos, diâmetros transversal e longitudinal de frutos). A análise de variância mostrou que as lâminas de irrigação influenciaram significativamente o (diâmetro de caule (P<0,05) nas avaliações realizadas em dezembro de 2009, janeiro e fevereiro de 2010; área foliar (P<0,01) para avaliações realizadas de janeiro a abril de 2010; número de folha (P<0,05) para as avaliações realizadas em março 2010 e (P<0,01) para abril de 2010); o potencial hídrico nas folhas (P<0,01) em todas as épocas de avaliação. E foi significativo o número de frutos (P<0,05), peso médio do fruto (P<0,05) e a produtividade (P<0,05). A produtividade máxima (6.763 kg ha-1) obtida em 60 dias de colheita, isto é, 25% do potencial produtivo anual do maracujazeiro foi obtida com aplicação da lâmina de 763,80 mm e estimando-se para seu potencial total para o primeiro ano de produção obteve-se o valor de 27.052 kg ha-1 ano-1; o peso médio de fruto variou de 0,207 kg (T6) e 0,159 kg (T1); foi registrado o número máximo de frutos (33.119 frutos ha-1) com lâmina de 760,21 mm. Os valores de Kc variaram de 0,43 a 1,04 com registro de máximo valor em 211 a 220 DAT. E o Kc médio obtido para a fase vegetativa foi de 0,57 e para fase de produção (floração e frutificação) de 0,94. Conclui-se que, as lâminas de irrigação mais adequadas para maracujazeiro amarelo se situam entre o equivalente 0,72*ETo e 1,00*ETo; as características morfofisiológicas de crescimento do maracujazeiro amarelo avaliadas, são influenciadas pela variação de lâminas de irrigação aplicada à cultura; a produtividade do maracujazeiro amarelo, peso médio e número de frutos são influenciados pela diferenciação de lâminas de irrigação aplicada à cultura.
119

Desenvolvimento e caracterização física, química e nutricional de farinhas de cascas e sementes de Passiflora edulis Sims e utilização na elaboração de cookies

Ramos, Bruna Cristina Zacante 08 November 2017 (has links)
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Departamento de Nutrição, Programa de Pós-Graduação em Nutrição Humana, 2017. / Submitted by Raquel Almeida (raquel.df13@gmail.com) on 2018-04-10T19:10:49Z No. of bitstreams: 1 2017_BrunaCristinaZacanteRamos.pdf: 1568754 bytes, checksum: 180ddf1f0e446162ffdfc9e201f9429d (MD5) / Approved for entry into archive by Raquel Viana (raquelviana@bce.unb.br) on 2018-04-20T19:51:02Z (GMT) No. of bitstreams: 1 2017_BrunaCristinaZacanteRamos.pdf: 1568754 bytes, checksum: 180ddf1f0e446162ffdfc9e201f9429d (MD5) / Made available in DSpace on 2018-04-20T19:51:02Z (GMT). No. of bitstreams: 1 2017_BrunaCristinaZacanteRamos.pdf: 1568754 bytes, checksum: 180ddf1f0e446162ffdfc9e201f9429d (MD5) Previous issue date: 2018-04-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). / A redução do desperdício de alimentos é uma necessidade considerando às projeções de aumento da população mundial. O aproveitamento de coprodutos da industrialização pode ser uma alternativa para atendimento desta demanda, visto que muitos resíduos da agroindústria possuem alto valor nutricional e/ou funcional, como é o caso das cascas e sementes de maracujá azedo (Passiflora edulis Sims). Na extração da polpa, estima-se que sejam gerados em torno de 250 mil toneladas/ano do coproduto, que poderia ser aproveitado como ingrediente de outros alimentos. O presente estudo teve por objetivo desenvolver farinhas alimentares a partir da mistura de casca e sementes desengorduradas e não desengorduradas provenientes da extração de polpa pelo método artesanal (onde existe a separação da casca da semente) e a partir da mistura de casca/semente obtida pelo agroindustrial (onde não ocorre a separação da casca e sementes), com o propósito de determinar a melhor relação entre a viabilidade técnica da fabricação, teor de bioativos e de aceitação sensorial das farinhas na fabricação de cookies. Para tanto, as cascas e sementes provenientes do processo artesanal e da mistura agroindustrial foram desidratadas pelo método de leito fluidizado. As farinhas foram obtidas por meio da moagem em moinho de faca, das matérias primas desidratadas: mistura agroindustrial, previamente caracterizada quanto a proporção casca e sementes, e das misturas de cascas com as sementes integrais e parcialmente desengorduradas, ambas nas proporções: 4:1, 2:1, 1:1, 1:2, e 1:4. Utilizou-se como fator de comparação a farinha de casca de maracujá comercial. A escolha das farinhas para a caracterização nutricional e elaboração dos cookies foi feita com base no rendimento, granulometria, teores dos fenólicos totais e dos flavonoides totais, e capacidade antioxidante (FRAP). A aceitação dos cookies foi determinada pelo método afetivo. A caracterização da matéria prima indicou que a secagem promoveu redução na umidade das cascas, sementes e mistura da agroindústria na ordem de 85%, 28% e 83% respectivamente. Verificou-se que a proporção casca/semente da mistura da agroindústria apresentou 94,5% de casca e 5,5% de sementes, indicando a relação 19 partes de casca para 1 parte de semente. O melhor rendimento de farinha foi obtido do produto da agroindústria (FRI), seguida da mistura da FCSI nas proporções 1:1, 1:2 e 4:1, e a de menor rendimento foi a de semente desengordurada na proporção de 1:4. A farinha obtida da mistura da agroindústria, bem como todas as proporções da FCSPD e a proporção 2:1 da FCSI obtiveram granulometria de até 1mm, enquanto que as demais apresentaram valores na ordem de 2 mm. As farinhas apresentaram teores de flavonoides de 168,7±47,5 mg/100g a 111,4±26,2 mg/100g e antocianinas de 18,1±11,2mg/100g a 7,3±2,2mg/100g. Foi detectado maiores concentrações de fenólicos totais nas farinhas com maiores proporções de sementes. A farinha com sementes parcialmente desengorduradas na proporção de 2:1 apresentou a melhor capacidade antioxidante (71,7 mg/L eq. 1000uM de trolox), enquanto que a farinha de casca comercial foi a que apresentou menor valor (31,6 mg/L eq. 1000uM de trolox). O resultado do FRAP se correlacionou de forma direta aos teores de fenólicos totais. Com base nos critérios tecnológicos e de qualidade foram selecionadas as farinhas nas seguintes proporções: FCSI 2:1, FCSPD 4:1 e a farinha da agroindústria 19:1. Os teores de lipídeos foram maiores na FCSI (21,7±0,4 g/100g), seguida da FCSPD (9,4b±0,5 g/100g) e FRI (6,2±1,2g/100g). A umidade média das farinhas foi inferior a 15% (g/100g). FCSI e FCSPD obtiveram valores superiores de proteínas (6,2 g/100g e 6,3 g/100g) em relação a FRI (4,2 g/100g), podendo essas serem classificadas como alimentos fonte de proteínas. A proporção de cinzas foi maior na FCSI (9,2 g/100g). O teor de carboidratos (obtido por diferença) variou de 81,4g/100g a 58,8g/100g, e o aporte energético variou de 455,3 Kcal/100g a 398,5Kcal/100g. Em relação ao parâmetro fibra alimentar não houve diferença estatística entre as farinhas experimentais mistas, podendo ainda serem consideradas farinhas fontes de fibras alimentares. Por meio das análises sensoriais verificou-se, que dentre os tratamentos, o biscoito tipo “cookie” feito com a adição de 25% de FCSI teve o maior índice de aceitação e as maiores médias para sabor, aparência, aroma, aceitação global e textura. / Reducing food waste is a necessity considering projections of increasing world population. The use of co-products from industrialization can be an alternative to meet this demand, since many wastes from the agroindustry have high nutritional and / or functional value, as is the case with the peels and seeds of passion fruit (Passiflora edulis Sims). In the extraction of pulp, it is estimated that about 250 thousand tons / year of the co-product, which could be used as an ingredient of other foods, will be generated. The objective of the present study was to develop food flours from the mixture of peel and defatted and non-defatted seeds obtained from pulp extraction by the artisanal method (where there is separation of the seed peel) and from the peel / seed mixture obtained by the (where no peel and seed separation occurs), with the purpose of determining the best relationship between the technical feasibility of the manufacture, bioactive content and sensory acceptance of flours in the manufacture of fiber - enriched cookies. For that, the peels and seeds from the artisanal process and the agroindustrial mixture were dehydrated by the fluidized bed method. Flours were obtained by milling the dried raw materials: an agroindustrial mixture, previously characterized as the peel and seed ratio, and the shell mixtures with the whole and partially defatted seeds, both in the proportions: 4: 1, 2: 1, 1: 1, 1: 2, and 1: 4. The commercial passion fruit pear meal was used as a comparison factor. The choice of flours for the nutritional characterization and preparation of the cookies was made based on yield, grain size, total phenolic and total flavonoid contents, and antioxidant capacity (FRAP). The acceptance of cookies was determined by the affective method. The characterization of the raw material indicated that drying promoted a reduction in the humidity of the peel, seeds and agroindustry mix in the order of 85%, 28% and 83% respectively. It was verified that the peel/ seed ratio of the agroindustry mixture showed 94.5% of husk 5.5% of seeds, indicating the ratio 19 of peel to 1 of seed. The best flour yield was obtained from the agroindustrial product (FRI), followed by mixing the FCSI in ratios 1: 1, 1: 2 and 4: 1, and the lowest yield was defatted in the proportion of 1: 4 . The flour obtained from the agroindustrial mixture, as well as all the proportions of the FCSPD and the 2: 1 ratio of the FCSI obtained granulometry of up to 1 mm, while the others presented values of 2 mm. The flours had flavonoid contents of 168.7 ± 47.5 mg / 100 g at 111.4 ± 26.2 mg / 100 g and anthocyanins from 18.1 ± 11.2 mg / 100 g at 7.3 ± 2.2 mg / 100 g . It was detected higher concentrations of total phenolics in the flours with higher proportions of seeds. The flour with 2: 1 partially defatted seeds had the best antioxidant capacity (71.7 mg / L and 1000uM trolox), while the commercial peel flour had the lowest value (31.6 mg / 1000 g of trolox). The FRAP result correlated directly with total phenolic contents. Based on the technological and quality criteria, flours were selected in the following proportions: FCSI 2: 1, FCSPD 4: 1 and 19: 1 agroindustrial flour. Lipid contents were higher in FCSI (21.7 ± 0.4 g / 100g), followed by FCSPD (9.4b ± 0.5g / 100g) and FRI (6.2 ± 1.2g / 100g). The average moisture content of the flours was less than 15% (g / 100g). FCSI and FCSPD obtained higher values of proteins (6.2 g / 100g and 6.3 g / 100g) in relation to FRI (4.2 g / 100g), which could be classified as protein source foods. The proportion of ashes was higher in FCSI (9.2 g / 100g). The carbohydrate content (obtained by difference) ranged from 81.4g / 100g to 58.8g / 100g, and the energy intake ranged from 455.3 Kcal / 100g at 398.5Kcal / 100g. Regarding the fiber dietary parameter, there was no statistical difference between the mixed experimental flours, and the sources of food fiber could be considered as flours. Through the sensorial analysis it was verified that among the treatments, the cookie type made with the addition of 25% FCSI had the highest acceptance rate and the highest averages for flavor, appearance, aroma, overall acceptance and texture.
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Monismo versus nao monismo no Brasil (1994-2004)

D'Agostini, Luciano Luiz Manarin 25 October 2013 (has links)
No description available.

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