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A gestão do património artístico em Portugal, no século XX-do regime jurídico à realidade práticaAmador, José Maria da Rocha Machado January 2002 (has links)
No description available.
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AVALIAÇÃO AMBIENTAL POR GEOPROCESSAMENTO NA SUB-BACIA DO RIO ANGASMARCA, REGIÃO LA LIBERTAD, PERU. / ENVIRONMENTAL ASSESSMENT BY GEOPROCESSING OF THE SUB-BASIN ANGASMARCA RIVER, IN LA LIBERTAD REGION, PERU.Rimarachin, Jorge Luis Diaz 11 April 2012 (has links)
The agricultural activities, without considering the potential and limitations on the land use, are a
potential source of environmental degradation. This study proposed the environmental diagnose of the
sub-basin Angasmarca river, in La Libertad region in Peru, using geoprocessing techniques. For the
execution of the work were incorporated into a Geographic Information System (ArcGIS 9.2) data
obtained by remote sensing (CBERS multispectral image and ASTER DEM G-2 digital elevation
model), topographic maps, rainfall data, soil analyzes and thematic maps existing (geology, soils,
ecology). From the morphometric characterization of the study area, we obtained the potential use of
land (from the roughness coefficient) characterizing areas liable to degradation by environmental
conflicts and identify areas susceptible to laminar erosion supported in Equation Universal Soil Loss
(USLE). From the analysis of hydrologic conditions and soils of watersheds evaluated by the circularity
index (CI), compactness coefficient (Kc) and form factor (Kf), the region is favorable to processes of
runoff, but nevertheless not subject to floods. In the evaluation of potential soil use, it was found that
33.18% of the sub-basin is appropriate for agricultural practice, 52.12% for pasture, 9.45% for
pasture/forestry and 5.25% for forestry. 50.88% (17963.53 ha) of the total area of the sub-basin is in
use conflicts therefore requires adaptations that reduce environmental degradation. In the analysis of
rainfall erosivity was found that the annual average value (EI30) is 4.762 MJ.mm.ha-1.h-1.year-1 (R
factor), with a monthly average of the 396.8MJ.mm.ha-1.h-1. In the rainy season (October to April) was
4678.5MJ.mm.ha-1.h-1 (considered erosive) and the dry season (May to September) of
83.5MJ.mm.ha1.h-1 (considered non-erosive). Therefore the estimates soil losses upper than
97.82t.ha-1.year-1 area located in the watersheds with the greater slopes (88.88km²), however, the
watersheds with the lowest soil loss area (mean 77.47t.ha-1.year-1 76.92 km2) area located on flatter
land. The mathematical modeling performed in the Geographic Information System enabled the
integration data of the estimates of erosion potential laminar and environmental assessment Physical-
Conservationist, permitting spatialize areas the potential risk both conflicts of land use, erosion and
environmental deterioration, the which allows to propose mitigation actions for areas that present the
biggest problems. / As atividades agropecuárias, sem considerar as potencialidades e limitações quanto ao uso das
terras, são uma fonte potencial de degradação do meio ambiente. O trabalho teve por objetivo fazer
um diagnóstico ambiental na sub-bacia do rio Angasmarca, na Região La Libertad no Peru, utilizando
técnicas de geoprocessamento. Para a execução do trabalho foram incorporados a um Sistema de
Informação Geográfica (ArcGIS 9.2) os dados obtidos por sensoriamento remoto (imagem
multiespectral CBERS e modelo digital de elevação ASTER G-DEM 2), cartas topográficas, dados
pluviométricos, análises de solo e mapas temáticos existentes (geologia, solos, ecologia). A partir da
caracterização morfométrica da área de estudos, obtivemos o uso potencial das terras (a partir do
coeficiente de rugosidade), caracterizando áreas passiveis de degradação por conflitos ambientais e
identificamos áreas susceptíveis à erosão laminar apoiado na Equação Universal de Perda de Solos
(EUPS). Da análise das condições hidrológicas e de solos das microbacias avaliadas através do
índice de circularidade (Ic), coeficiente de compacidade (Kc) e fator de forma (Kf), a região é favorável
a processos de escoamento superficial, mas no entanto não sujeita a enchentes. Na avaliação do uso
potencial do solo, constatou-se que 33,18% da área da sub-bacia apresenta-se apropriada para a
prática agrícola, 52,12% para pastagem, 9,45% para pastagem/florestamento e 5,25% para
florestamento. 50,88% (17.963,53ha) da área total da sub-bacia encontra-se em conflito de uso,
portanto necessita de adequações que diminuam a degradação ambiental. Na análise da erosividade
das chuvas verificou-se que o valor médio anual (índice EI30) da sub-bacia é de 4.762MJ.mm.ha-1.h-
1.ano-1 (fator R), com uma média mensal de 396,8MJ.mm.ha-1.h-1. Já para o período chuvoso (outubro
a abril) foi de 4.678,5MJ.mm.ha-1.h-1 (considerado erosivo) e para o período seco (maio a setembro)
de 83,5MJ.mm.ha-1.h-1 (considerado não erosivo). Portanto verificou-se que estimativas de perdas de
solo superiores a 97,82t.ha-1ano-1, estão localizadas em microbacias de maiores declividades,
totalizando 88,88km2 da área da sub-bacia, entretanto, as microbacias onde ocorrem menores perdas
de solos (média de 77,47t.ha-1ano-1 - 76,92 km2), estão localizadas em terrenos mais planos. As
modelagens matemáticas realizadas no Sistema de Informação Geográfica possibilitaram a
integração de dados das estimativas do potencial de erosão laminar e da avaliação ambiental Físico-
Conservacionista, permitindo espacializar às áreas de risco potencial tanto de conflitos de uso do
solo, erosão e deterioração ambiental, o que permite propor ações mitigadoras para áreas que
apresentam maiores problemas.
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Qualidade de filé de tilápia (Oreochromis niloticus) embalado com atmosfera modificada / Quality fillet of tilapia (Oreochromis niloticus) packed under modified atmosphereAraújo, Nkarthe Guerra 14 April 2014 (has links)
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Previous issue date: 2014-04-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The Nile tilapia second most widely cultivated species of fish in the world, stands out in Brazil as the main, with the filet the preferred form of consumption. However, due to the chemical, microbiological and enzymatic reactions present in your muscle, favored by the presence of oxygen, found in high concentrations in normal atmosphere, is also considered a highly perishable food. Thus, many works have been performed in order to prolong their shelf life. In this research a modified atmosphere packaging combined with refrigeration was studied. To run the experiments , tilapia weighing between 700g and 800g were purchased in the city of Bananeiras-PB and transported in insulated box with ice in a 2:1 ratio to the Laboratory of Fish Technology, Federal University of Paraiba , where the originally underwent steps of gutting , heading, washing, removal of skin and filleting. The fillets were then subjected to different treatments, with the control sample, was packaged in conventional packaging (polyethylene) at 4 ± 1°C, while in modified atmosphere treatments were conditioned at the same temperature in nylon - polyethylene containers with removal of the air (vacuum) and two different mixtures of gases: 80%CO2 + 20%O2 and 100%CO2. Throughout the storage period, microbiological, physical, chemical and sensory analysis was conducted. It was found that the treatments with 100% CO2 followed by vacuum did not favor development and sulfite -reducing Clostridium were more effective in inhibiting the growth of psychrotrophic bacteria and coliform microorganisms, extending the shelf life of the fillets for six days 22 e 20 days, respectively. The results of physical and chemical analysis, it was observed that these treatments were more effective in maintaining its characteristics of freshness for longer (17 and 20 days ) without , however, affecting its nutritional value. However, the modification of the normal atmosphere, especially at high CO2 concentrations affect the sensory quality of the steaks over the storage period, limiting its shelf life, and the vacuum treatment which kept the sensory attributes unchanged for longer (12 days). It is recommended therefore, under the proposed conditions of this research, packaging under vacuum to preserve the fillet of Nile tilapia. / A tilápia do Nilo, segunda espécie de peixe mais cultivada no mundo, destaca-se, no Brasil, como a principal, sendo o filé a forma preferida de consumo. Entretanto, devido as reações químicas, enzimáticas e microbiológicas presentes em seu músculo, favorecidas pela presença do oxigênio, encontrado em elevadas concentrações na atmosfera normal, é também considerada um alimento altamente perecível. Deste modo, diversos trabalhos vem sendo realizados com o objetivo de prolongar sua vida de prateleira. Nesta pesquisa foi avaliada a embalagem com atmosfera modificada aliada a refrigeração. Para execução dos experimentos, tilápias com peso entre 700g e 800g foram adquiridas no município de Bananeiras-PB e transportadas em caixa térmica com gelo na proporção 2:1 para o Laboratório de Tecnologia de Pescado da Universidade Federal da Paraíba, onde inicialmente foram submetidas as etapas de evisceração, descabeçamento, lavagem, remoção da pele e filetagem. Os filés obtidos foram, então, submetidos aos diferentes tratamentos, sendo que, a amostra controle, foi acondicionada em embalagem convencional (polietileno) a 4 ± 1°C, enquanto, nos tratamentos com atmosfera modificada, foram acondicionadas a mesma temperatura, em embalagens de nylon-polietileno com remoção do ar (vácuo) e duas diferentes misturas de gases: 80% CO2+ 20% O2 e 100% CO2. Durante todo o período de armazenamento, foram realizadas análises microbiológicas, físicas, químicas e sensoriais. Verificou-se que os tratamentos com 100% CO2 seguido pelo vácuo não favoreceu o desenvolvimento de Clostridium sulfito redutores e foram mais eficazes na inibição do crescimento de bactérias psicrotróficas e de micro-organismos do grupo coliformes, estendendo a vida de prateleira dos filés de seis dias para 22 e 20 dias, respectivamente. Pelos resultados das análises físicas e químicas, observou-se que estes tratamentos também foram mais eficazes na manutenção de suas características de frescor por mais tempo (17 e 20 dias) sem, contudo, afetar seu valor nutricional. Entretanto, a modificação da atmosfera normal, especialmente com elevadas concentrações de CO2 afetou a qualidade sensorial dos filés ao longo do período de armazenamento, limitando sua vida de prateleira, sendo o tratamento a vácuo o que manteve os atributos sensoriais inalterados por mais tempo (12 dias). Recomenda-se deste modo, nas condições propostas desta pesquisa, o acondicionamento a vácuo para a conservação do filé de tilápia do Nilo.
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Teste de condutividade elétrica para sementes de milho e de soja armazenadas sob baixa temperatura /Rosa, Mariana Silva. January 2009 (has links)
Orientador: Roberval Daiton Vieira / Banca: Nelson Moreira de Carvalho / Banca: Julio Marcos Filho / Resumo: O teste de condutividade elétrica é recomendado para avaliar o vigor de sementes de ervilha e é sugerido para soja. Entretanto, alguns cuidados devem ser adotados para esse teste, quando conduzido para sementes armazenadas sob condições de baixa temperatura. Assim, o presente trabalho teve como objetivo verificar se a utilização de períodos de repouso de sementes em temperaturas mais altas antes da embebição no teste de condutividade elétrica elevaria a viabilidade do teste para sementes de milho e soja, armazenadas a 10 °C. Foram utilizados cinco lotes de sementes para cada espécie, com germinação semelhante. Após as avaliações iniciais, os lotes de soja foram armazenados por 15 meses e os de milho por 16 meses sob baixa temperatura. Desse modo, foram realizadas análises laboratoriais preliminares (teor de água; germinação e vigor: envelhecimento acelerado; teste de frio e condutividade elétrica), repetidas periodicamente após o armazenamento em câmara a 10 °C e 60% de umidade relativa aos 3, 6, 9, 12 e 15 meses para soja e aos 4, 8, 12 e 16 meses para milho. A partir da segunda época de avaliação para ambas as espécies foi inserida nova variável ao teste de condutividade elétrica, denominada período de repouso das sementes, utilizada entre a remoção das sementes da câmara fria e o início da embebição. / Abstract: Electrical conductivity test is recommended to evaluate vigor of pea seeds and suggested for soybean. However, some cares must be taken for this test, when conducted for seeds stored at low temperature. Thus, the present work was carried out in order to verify if the use of rest time at higher temperature of seeds before the imbibitions for the electrical conductivity test can increase the viability of the test for maize and soybean seeds, stored at 10 °C. Five seed lots for each species, with similar germination levels were used. After the initial evaluations, soybean seed lots were stored during 15 months and maize seed lots during 16 months at low temperature. The laboratory analysis (seed moisture content; germination and vigor: accelerated aging; cold and electrical conductivity tests) were performed initially and repeated periodically after the storage (10 °C and 60% of air relative humidity) at 3, 6, 9, 12 and 15 months for soybean and 4, 8, 12 and 16 months for maize. Since the second evaluation for both species a new variable was added to the electrical conductivity test, denominated rest time of the seeds, used between the removal of the seeds of the cold chamber and the start of the imbibition for the conductivity test. The rest time periods of 0, 6, 12 and 24 hours were used, at two temperatures, 20 e 25 to 30 °C, aimed to verify, in this way, the effect of these periods and temperatures on the results of the electrical conductivity throughout of the storage period at low temperature. / Mestre
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Globalización e insostenibilidad ecológica y social / Globalización e insostenibilidad ecológica y socialGuevara, Leonor 10 April 2018 (has links)
Through history of societies we may consider recent the fact that differences amongeconomic activities affect those that suffer polítical control. Previous invasions of the named discovery of America did not have involvement similar to those of the present interregionallinks.Sorne globalization indicators are visible from past to modero times and resulted from the continuous technological advances in the mass production of goods as well as in communications, massive migration of the labor force in search of places that offer better job opportunities, the relationship between world production and commercialization levels, and capital flow without regard of international borders. However, these conditions are not same neither for all regions nor for the members of all societies.The variations caused by the recent structure of the economic system make theeconomic geography to be further separare from politics, even at the heart of societies due to the fact that sorne social segments are more integrated with other territories rather than with their own.To participare in the world economy, there are new competitive challenges thathave significant effects on a nation's environmental policies, making them unacceptable beca use they disagree with its national interests. There is a need for the establishment of indexes to measure the sustainability of development, because different frameworks determine each of the three objectives-social, environmental and economic.If we want to achieve a better quality of life for everybody, induding the unborn, then we need to build a development project that takes human needs intoconsideration, without biodiversity loses and environmental deterioration. / A lo largo de la historia de los pueblos se puede considerar reciente el hecho de que la diferencia entre las actividades económicas afecte las de aquellos que sufren el control político de otros. Las invasiones previas al denominado descubrimiento de América no tuvieron las implicaciones que hoy tienen los vínculos interregionales, aunque no tengan carácter impositivo.Algunos de los indicadores de globalización desde ese primer momento hasta hoy se desprenden de los continuos avances tecnológicos tanto para la producción en grandes cantidades como para las comunicaciones; también, de las migraciones masi vas de población en busca de mayores y mejores oportunidades de vida que ofrecían los descubrimientos de nuevos territorios en el pasado y de oportunidades de empleo en la actualidad; de la relación entre la producción mundial y los niveles de comer cialización; y del movimiento de capitales a través de espacios sin fronteras. Sin em bargo, no es la misma situación para todas las regiones ni para todos los miembros de toda la sociedad.Las variaciones provocadas por la reciente estructura del sistema económico hacen que la geografía económica coincida cada vez menos con la política aun al inte rior de los países, ya que ciertos segmentos de sus sociedades están más integradas con los de otros territorios que con los que administrativamente están más cercanos, hasta el punto de que, estando en el poder, han llegado a desreglar sus propios mercados y a abrir el comercio y el sector financiero en favor de las potencias económicas.Se considera que para lograr inserción en la economía mundial impuesta por la globalización, surgen nuevos retos en materia de competitividad, retos que tienen graves repercusiones sobre la política ambiental, hasta querer ganar competitividad a costa de ceder principios en ella. Esto resulta inviable no solo por oponerse a los intereses nacionales de mediano y largo plazo, sino también por contradecir acuerdos y compromisos internacionales establecidos.Una situación que facilita esa concepción es la falta de indicadores para medir la sostenibilidad del desarrollo, ya que cada uno de los tres objetivos -el social, el ambiental y el económico- se determinan con parámetros que no tienen un denominador común que permitan una conversión universal. Si se quiere mejor calidad de vida para todos -incluyendo a los que no han nacido- hay que plantear un proyecto de desarrollo que responda a las necesidades humanas, pero que no signifique pérdidas de biodiversidad ni deterioros ambientales irreversibles. En conclusión, se requiere dar un vuelco al anhelo globalizador con un modelo de desarrollo que cualifique la experiencia vital y que sea ecológicamente sostenible.
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Formation of Sulphides in the Canadian High Arctic Large Igneous Province; Testing the Influence of Sedimentary Rocks / Bildandet av sulfider i den kanadensiskahögarktiska magmatiska provinsen: prövning av sedimentära bergarters inflytandeHagerfors, Erika January 2018 (has links)
Large Igneous Provinces (LIPs) form during short-lived pulses of extensive magmatic activity. LIPs are known for their ability to affect global climate as well as for their Ni-Cu-PGE ore potential. A key factor that controls the intensity of the climate impact of a LIP and its ore potential is the assimilation of volatile-rich sedimentary host rocks. Magmas of the High Arctic Large Igneous Province (HALIP), exposed in the Arctic, intruded volatile-rich black shales, carbonates and evaporites in the Canadian Arctic Islands, offering a great opportunity for studying magma-sediment interaction. The purpose of this study is to test whether assimilation of sedimentary sulphide can promote sulphide immiscibility in magma and thus aid formation of Ni-Cu-PGE ore bodies. This is done by analysing sulphur isotopes in pyrite grains hosted in a HALIP dolerite sill, which was emplaced into black shale, by using Secondary Ion Mass Spectrometry (SIMS). Four dolerite samples are analysed; two coming from the lower contact margin of the sill, one from 60 cm into the sill and one sample from a basaltic vein at the upper contact margin of the sill. A total of 14 pyrite grains (n = 246 individual SIMS spot analyses) were analysed for their sulphur isotope ratios. The results of the SIMS analyses show that all analysed sulphides have highly negative δ34S values ranging from -19.5 to -5.7‰ (average δ34S = -8.2 ± 0.83‰, 2SD), which therefore differ largely from that of the primitive mantle (0 ± 1.8‰). In order to put our four analysed dolerite samples into a broader context, δ34S data of our sulphides are compared with whole-rock δ34S and δ18O data from Hare Fiord shale and dolerite samples. The δ34S values of the sulphide samples from the sill typically trend toward the negative sulphur isotope composition of the sulphides in the surrounding shale, and the shale surrounding the sill experiences a loss of 32S near the contact of the sill. This indicates that sedimentary light sulphur (32S) has been locally incorporated into the sill by the surrounding shale, resulting in negative δ34S values in the magmatic sulphides. Since sulphide immiscibility in the Hare Fiord sill was triggered by assimilation of sulphur from host rock shale, the igneous rocks of the HALIP may be prospective for Ni-Cu-PGE mineralization, though more studies are needed. Furthermore, our results suggest that incorporation of crustal sulphur increased the volatile budget of HALIP magmas, which therefore could have contributed to a deterioration of the environmental conditions during the emplacement of the HALIP. / Stora magmatiska provinser (på engelska Large Igneous Provinces, LIPs) är vulkaniska event då enorma mängder magma avsätts över en väldigt stor yta under ett, i ett geologiskt perspektiv, kort tidsspann. Dessa stora vulkaniska utbrott har väckt stort intresse då de är samtida med flera av de största massutdöendena i jordens historia, men också för att en viss typ av sulfidmalm rik på nickel, koppar och platinametaller (Ni-Cu-PGE malmer) ofta förekommer i provinsernas magmagångar och magmakammare. En viktig faktor som till stor del avgör en magmatisk provins påverkan på klimatet och potentiella malmförekomster är inkorporering av sedimentära bergarter till magman som, när de hettas upp, kan frigöra gaser rika på svavel och kol. I Kanadas arktiska öar trängde magma tillhörande den högarktiska magmatiska provinsen (HALIP) in i svart skiffer, karbonater och evaporiter, som är sedimentära bergarter rika på flyktiga ämnen. Denna magmatiska provins erbjuder därför stora möjligheter till att studera interaktionen mellan magma och sedimentära bergarter. Syftet med denna studie är att testa om inkorporering av sedimentärt svavel kan främja bildandet av sulfidsmälta i magma och därigenom bidra till bildandet av sulfidmalmer. Detta görs genom att analysera svavelisotoper i sulfidmineral i prover från en magmagång, som trängde in i en skifferformation, tillhörande den högarktiska magmatiska provinsen i norra Kanada. Genom att analysera svavelisotopkvoten (δ34S) i sulfidmineral kan man få information om huruvida svavlet i mineralen är av sedimentärt ursprung (där skiffer generellt har negativa δ34S värden) eller om svavlet har δ34S värden liknande de från manteln (som har δ34S värden runt 0‰), vilket i så fall skulle innebära att magman inte har inkorporerat sedimentärt svavel. Genom att använda masspektrometri av typen SIMS analyseras totalt 14 sulfidmineralkorn (n = 246 individuella SIMS punkter) för deras svavelisotopkvoter. Resultatet av studien visar att alla analyserade sulfidmineral har mycket negativa δ34S värden mellan -19.5 och -5.7‰ (med ett δ34S medelvärde på -8.2 ± 0.83‰, två standardavvikelser). Genom att jämföra våra δ34S värden med δ34S och δ18O värden för andra prover från både magmagången och den omgivande skiffern kunde vi se att δ34S värdena för sulfidmineralen i de yttre delarna av magmagången har liknande negativa värden som den omgivande skiffern, och att δ34S värdena för skiffern närmast magmagången är mer positiva. Detta tyder på att sedimentärt svavel i kontakten mellan magmagången och skiffern har blivit inkorporerat i magman från den omgivande skiffern. Våra resultat tyder därför på att sulfidmineralen i våra prover från magmagången bildades genom assimilering av svavel från den omgivande skiffern. Detta innebär i sin tur att den kanadensiska högarktiska magma provinsen potentiellt kan vara en källa för sulfidmalm, även om ytterligare studier behövs. Dessutom visar våra resultat att inkorporering av sedimentärt svavel förmodligen ökade de vulkaniska gaserna i magman, vilket kan ha bidragit till klimatförändringar relaterade till den vulkaniska aktiviteten av den högarktiska magmatiska provinsen.
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Study of agro-composite hemp/polypropylene : treatment of fibers, morphological and mechanical characterization / Étude des agro-composites chanvre/polypropylène : traitement des fibres, caractérisation morphologique et mécaniqueHan, Hongchang 04 February 2015 (has links)
L’utilisation des fibres végétales dans les polymères composites suscite de nombreuses investigations. Avant de mélanger les fibres végétales dans le polymère, un traitement chimique peut être effectué permettant de réduire l’hydrophilicité des fibres et d’améliorer l'adhérence à l’interface fibre/matrice. Dans cette thèse, l'eau et l'alcali sont utilisés d'abord pour traiter les fibres de chanvre, puis trois agents silane : 3-(triméthoxysilyl)propyl méthacrylate (MPS), N-[3- (triméthoxysilyl)propyl] aniline (PAPS) et (3-Aminopropyl)-triéthoxysilane (APS), sont utilisés pour modifier plus ou moins la surface des fibres de chanvre. Ces fibres traitées ou modifiées sont ensuite mélangées avec le polypropylène (PP) pour la fabrication des composites. Les effets de ces différents traitements sur la structure, les composants et l’hydrophilicité des fibres, et les propriétés mécaniques de ces composites sont mis en évidence. Nous avons étudié ensuite l’effet de vieillissement sur leurs comportements mécaniques, notamment l'humidité, la température et le rayonnement ultraviolet. Les résultats ont montré que le traitement de fibres par l'eau et l’alcali a des effets considérables sur la structure de fibres, les propriétés mécaniques et la durabilité des composites renforcés. La modification par l'agent de silane a une influence moins importante sur la structure des fibres, pourtant son groupe fonctionnel a une influence significative sur les propriétés mécaniques et la résistance au vieillissement des composites renforcés / Using agro fiber as reinforcement of polymer com-posites attracts numerous investigations due to the good mechanical properties and environmental benefits. Prior to blend agro fiber with polymer, chemical treatment can be employed to treat agro fiber for the purpose of reducing the hydrophilicity of fiber and improving the interfacial adhesion fi-ber/polymer matrix. In this thesis, water and alkali are utilized to treat hemp fiber firstly and then three silane agent as 3-(Trimethoxysilyl)propyl methacry-late (MPS), N-[3-(Trimethoxysilyl)propyl]aniline (PAPS) and (3-Aminopropyl)-triethoxysilane (APS) are employed to modify the hemp fiber surface. These treated or modified fibers are blended respectively with polypropylene (PP) to fabricate the hemp fiber/PP composites. The effects of these different treatments on the structure, components and hydro-philicity of fiber, and the mechanical properties of the reinforced PP composites are studied. Moreover, the accelerated ageing experiments including humidity, temperature and ultraviolet of the reinforced PP composites are conducted. The results showed that the fiber treatment of water and alkali has a considerable effect on fiber structure, mechanical properties and durability of the reinforced compo-sites. The silane agent modification of fiber has less influence on the fiber structure but its functional group has great influence on the mechanical proper-ties and ageing resistance of the reinforced compo-sites.
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Manufacturing of hemp/PP composites and study of its residual stress and aging behavior / Elaboration des chanvre/PP composites et étude des contraintes résiduelles et du comportement de vieillissementsZhang, Xiaohui 31 May 2016 (has links)
Depuis quelques années les matériaux composites à base de fibres naturelles sont de plus en plus utilisés pour les nouvelles performances qu’ils proposent. C’est surtout au niveau des fibres naturelles que de nouvelles propriétés sont proposées. Dans ce travail, nous nous sommes essentiellement intéressés aux fibres naturelles de chanvre. Ces fibres sont déjà fortement utilisées dans l’automobile et la construction. En Europe, ces fibres sont produites principalement en France et plus particulièrement dans l’Aube. Pour développer des agro-composites hautes performances, c’est sous la forme de fibres longues et de tissus que nous avons choisi d’orienter ce travail de thèse. Nous avons choisi la thermocompression pour élaborer des plaques avec des tissus de chanvre et une matrice en polypropylène (PP). Ce travail permet de voir l’influence des conditions d’élaboration sur le comportement mécaniques de ces agro-composites. Cette thèse permet aussi de voir l’effet du vieillissement aux UV et à l’Humidité sur les performances de ces matériaux. Enfin une analyse des contraintes résiduelles par la méthode du trou incrémental permet de voir leurs effets sur ces agro-matériaux / In recent years composite materials based on natural fibers are more and more used for their new performances. Natural fibers propose attractive environmental, mechanical and thermal properties.In this work, we are firstly interested in hemp fibers. These fibers are already used in the automotive and construction industry. In Europe, these fibers are produced mainly in France and especially in Aube. To develop agro-composites with high performances, we have focused this thesis on hemp woven. We chose to elaborate the plates with hemp woven and a polypropylene matrix (PP) by compression molding. This work allows us to see the influence of elaboration conditions on the mechanical behavior of these agro-composites. This thesis also allows us to see the effect of aging conditions UV and humidity on the performance of these materials. Finally an analysis of residual stresses determined by the hole drilling method is proposed to see their effects on the agro-materials
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Avaliação do comportamento bacteriano e alterações sensoriais em tilápias do Nilo (Oreochromis niloticus) durante estocagem em gelo / PERFORMANCE EVALUATION AND BACTERIAL CHANGES IN SENSORY NILE TILAPIA (Oreochromis niloticus) DURING STORAGE IN ICELeite, Lana Oliveira January 2013 (has links)
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Previous issue date: 2013 / LEITE, Lana Oliveira. Avaliação do comportamento bacteriano e alterações sensoriais em tilápias do Nilo (Oreochromis niloticus) durante estocagem em gelo. 2013. 59 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Engenharia de Pesca, Fortaleza-CE, 2013 / Fish is a food susceptible to deterioration due their intrinsic characteristics, requiring bacterial monitoring in postmortem storage. Thus, the objective was to quantify mesophilic, psychrotrophic, psychrophilic bacteria in Nile tilapia (Oreochromis niloticus) during to 21 days of storage under the action of ice at temperature refrigeration. Four experiments were conducted, separated to two groups, gutted and ungutted, with eight samples totaling 32 samples. Every three days was taken a exemplar of tilapia for analyzes of the trial: sensory evaluation according to the Quality Index Method (QIM) adapted to the Nile tilapia and heterotrophic bacterial count of cultivable. In sensory analysis of raw fish attributes were assessed: general appearance, eyes, gills, muscles and texture of the fish, according to the Sensory Characters Sum (S.C.S). To each specimen were quantified bacterial groups: psychrophilic (23 °C), psychrotrophic (7 °C) and mesophilic (35 °C), the surface and the muscle, using the method of standard plate count (SPC). There was no statistical difference between the three bacterial groups analyzed the significance level of 5% within the same treatments and between groups. The storage time was highly correlated with the counting of bacterial groups and increased QIM for both eviscerated fish, and for those not drawn. It was considered that the process of evisceration on the premises of the fish did not increase its useful life. It is suggested, therefore, greater attention in the process of gutting fish markets that sell live fish, because this process was not carried out effectively to security and recovery product. / O pescado é um alimento susceptível à deterioração devido às suas características intrínsecas, sendo necessário o monitoramento bacteriano no armazenamento pós-morte. Dessa forma, objetivou-se quantificar bactérias, psicrotróficas, psicrófilas e mesófilas em tilápias do Nilo (Oreochromis niloticus) durante 21 dias de estocagem sob ação do gelo. Foram realizados quatro experimentos, separados em dois grupos, não eviscerados e eviscerados, cada um com oito amostras perfazendo um total de 32 amostras. A cada três dias era retirado um exemplar de tilápia para as análises do experimento: sensorialmente, conforme a avaliação do Método do Índice de Qualidade (MIQ), adaptado à tilápia do Nilo e microbiologicamente. Na análise sensorial do peixe cru foram avaliados os atributos: aspecto geral, olhos, brânquias, textura e musculatura dos peixes, segundo os somatórios dos caracteres sensoriais (S.C.S). De cada exemplar foram quantificados os grupos bacterianos: psicrotróficos (7°C), psicrófilos (23°C), e mesófilos (35°C), na superfície e no músculo, pelo método de Contagem Padrão em Placas (CPP). Não houve diferença estatística entre os três grupos bacterianos analisados à um nível de significância de 5% dentro dos mesmos tratamentos e entre os grupos. O tempo de estocagem apresentou alta correlação com a contagem dos grupos bacterianos e o aumento do MIQ, tanto para os peixes eviscerados, quanto para os não eviscerados. Foi considerado que o processo de evisceração no local de venda dos peixes não aumentou sua vida útil. Sugere-se, portanto, uma maior atenção no processo de evisceração em peixarias que comercializam peixes vivos, pois esse processo não foi realizado de forma eficaz para segurança e valorização do produto.
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Transfer to higher level of care : a retrospective analysis of patient deterioration, management as well as processes involvedLe Roux, Estelle 06 1900 (has links)
In-patient deterioration is a global phenomena and timely recognition and action improves outcome. Intensive care facilities are scarce and expensive and therefore patient care must be optimal. A retrospective health record analysis was used for this study.
The findings indicated that nursing personnel do not recognize patient deterioration timeuously. However, the implementation of an outreach team and clinical markers training program improved the recognition of patient deterioration in general wards with three hours and 40 minutes.
It is recommended to implement a comprehensive hospital program that addresses the basic knowledge and skills of general ward personnel to observe, recognize, assess and intervene to patients with clinical deterioration. Together with an extensive training program, a basic physiological parameters guideline to activate a team of experts to the bedside, such as an Outreach team, assist nursing personnel to recognize and manage those patients timeuously and ensure treatment in an appropriate level of care. / Health Studies / M. A. (Health studies)
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