Rheologic
Mostrando 1-12 de 26 artigos, teses e dissertações.
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1. Líquidos nemáticos e relatividade geral
In the mean 80´s, it was proposed that the rheologic properties of liquidcrystal could be obtained through affine transformation, in which the interaction potential of aspheric molecule is deformed to assume the ellipsoidal shape of potential liquid crystal´smolecular interaction. When this procedure is done point to point, the usuals derivatives donot get
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 27/07/2010
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2. Rheological analysis of water clay compositions in order to investigate mudflows developing in canals
This paper describes the physical and rheological property mixtures of water and kaolinitic clay that form the interstitial fluid found in muds from inundations or torrential lava. Several compositions with varying volume concentrations (Cv) were tested in a high-precision R/S rheometer (shear rate x shear stress). The rheometric parameters such as critical
Journal of the Brazilian Society of Mechanical Sciences and Engineering. Publicado em: 2009-03
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3. Rheological and thermal behavior of amaranth starch-sodium caseinate systems : effect of sugar addition and acidification time / Comportamento reologico e termico de sistemas amido de amaranto-caseinato de sodio : efeito da adição de açucar e tempo de acidificação
The starches are frequently added to the foods owed their properties and water retention, as colloidal emulsion-estabilizing agents. The amaranth is a low cost culture, and his starch, a new ingredient with potential industrial use. The caseinato of sodium is a salt derived of the casein thoroughly used as emulsion in foods. The study proteins and polysaccha
Publicado em: 2008
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4. Study of hydrodynamics and heat transference from liquid whole egg through plate with three formats chevron / Estudo da hidrodinamica e transferencia de calor do ovo integral liquido atraves de placas com tres formatos chevron
At this work are showed the heat transference and hydrodynamics of liquid egg flow between ducts with corrugated walls, simulating plate heat exchangers. The contour conditions admitted was the constant temperature in the walls during the fluid heating. The whole egg rheology was experimentally determinated in a extend temperature range (289 ? 335K). The egg
Publicado em: 2008
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5. Estudo de conformação de cerâmicas à base de zircônia para aplicação em células a combustível do tipo óxido sólido / STUDY OF TAPE CASTING OF YTTRIA STABILIZED ZIRCONIA FOR APPLY IN SOLID OXIDE FUEL CELL
The hydrogen economy has been risen as new option for supply the growing global demand for energy. A fuel cell is an electrochemical device able to use hydrogen as a energy source. Carbon dioxide (CO2) emission is very low so it is ecologically friendly, once energy is produced by a reaction of hydrogen and oxygen. The production of energy from hydrogen fuel
Publicado em: 2008
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6. Influência da cal hidratada nas idades iniciais da hidratação do cimento Portland - estudo em pasta. / Influence of hydrated lime on initial stages of hydration of Portland cement - paste study.
In the last decades, scientific and technological progress has shown a significant advance in the process of obtaining lime; however, there is gap knowledge with relation to its action when employed together with Portland cement. The use of lime in finishing mix mortars has only been positively associated to the fresh state plasticity and ability to deformat
Publicado em: 2008
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7. Application of peptides in cosmetics: development of formulations, stability and efficacy / Aplicação de peptídeos em cosméticos: desenvolvimento de formulações, estabilidade e eficácia
The aim of this study was the development, evaluation of the stability and the efficacy of cosmetic formulations containing acetyl hexapeptide-3 (AHP), or acetyl tetrapeptide-5 (ATP) or mixture of di- and peptides (DTP). For this purpose the 6 following formulations (F) were developed: F1- containing hydroxyethyl cellulose (HEC), methylphenyl polysiloxane (M
Publicado em: 2008
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8. Influência do pH sobre a estabilidade de suspensões de alumina estabilizadas eletroestericamente
In this work, aqueous suspensions of aluminas with different particle sizes were evaluated. The effect of pH on the electrosteric stabilization using PMAA-NH4 (ammonium polymethacrylate) as deflocculant was studied. The amount of deflocculant was optimized and rheologic properties were determined at four different pH values. Sedimentation was also evaluated.
Química Nova. Publicado em: 2007-02
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9. Effect of temperature, concentration, polarity of the medium and surfactant on the rheology and morphology of emulsions with oil from mature fields. / Efeito da temperatura, concentração, polaridade do meio e de surfactante sobre a reologia e morfologia de emulsões com petróleo oriundo de campos maduros.
Durante a extração e transporte do petróleo proveniente de campos maduros existem dois grandes problemas que são: a formação de depósitos orgânicos e a presença de água emulsificada. Estes causam obstrução total ou parcial da secção transversal das tubulações e um acréscimo considerável na viscosidade do óleo, gerando por várias vezes lon
Publicado em: 2007
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10. Time-dependent behavior of sulphatic rocks of the anhydrite and gypsum / Comportamento dependente do tempo de rochas sulfáticas de anidrita e gipso
The purpose of this thesis is to contribute for the knowledge of time-dependent behavior of sulfatic rocks of anhydrite and gypsum. Emphasis is given to provide straightforward arguments about physical mechanisms responsible for creep observed in some underground excavations in those rocks in Europe. Explanation for this phenomena is not clear yet and studie
Publicado em: 2005
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11. Influência do C3A em pastas de cimento portland : avaliação das propriedade reológicas / Influence of C3A on portland cement pastes : valuation of the rheologic properties
The production of high performance concrete with special rheologic properties, fluidity and durability, demands the knowledge of physical and chemical characteristics of the used cement. The herein research studies the C3A influence on cement pastes, in order to add knowledge to all the aspects that can contribute to its rheologic behavior and, consequently,
Publicado em: 2004
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12. Production of biopolímeros for microrganismo modified geneticamente. / Produção de biopolimeros por microrganismos modificados geneticamente.
This work aimed to study the production of biopolymers by genetically modified microorganisms. Xanthomonas campestris pv campestris and Xanthomonas axonopodis pv manihotis were studied as a receiver lineage of the genes under study, and Zymomonas mobilis and Xylella fastidiosa as donor lineages. The first chapter is a revision article about the production of
Publicado em: 2003