Reactivity Of Aggregates
Mostrando 1-12 de 30 artigos, teses e dissertações.
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1. Study of quartzite waste from southwest of the Minas Gerais as concrete coarse aggregates / Estudo tecnológico em rejeitos de quartzitos do sudoeste de Minas Gerais para utilização como agregado graúdo no concreto
The Southwest of the Brazilian State of Minas Gerais is nationally known by the production of quartzite used as floor and wall covering. The extraction of the quartzite in the region, even when obey the determinations of the ambient agencies, generates a great amount of waste. The waste generated in the extraction and processing of the slates is an enormous
Publicado em: 2009
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2. Study of alkali-silica reaction gel in concrete by high-resolution nuclear magnetic resonance / Estudo da reação álcali-sílica em concretos através de ressonância magnética nuclear de alta resolução
The alkali-silica reaction (ASR) occurs between structurally distorted or disordered silica and aqueous solutions of alkaline hydroxides, as KOH or NaOH. The product of the ASR is an alkali-silicate gel, which may expand upon water absorption. When the ASR occurs in mineral aggregate used in concrete, the process of reaction and expansion cause the decrease
Publicado em: 2009
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3. Influência da substituição do agregado miúdo natural por agregado reciclado fino em propriedades de argamassas e concretos
Construction and demolition waste (CDW) recycling has been a good alternative to reducing the impact caused by the consumption and high demand of raw materials for civil construction. In this sense, it has been tried to incorporate those wastes in the production of concrete and decrease strength mortar, what would increase its potential use. This study was d
Publicado em: 2008
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4. Efeito de adições ativas na mitigação das reações álcali-sílica e álcali-silicato. / Effect of mineral admixtures in controlling the alkali-silica reaction and alkali-silicate reaction.
The alkali-aggregate reaction is a pathologic manifestation that can induce the premature distress and loss in serviceability of concrete structures affected. It is directly associated to the selection of materials (cement, coarse and fine aggregates, water and additives), as the interaction between these materials and environmental condition will grant the
Publicado em: 2007
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5. Reação álcali-agregado : avaliação do comportamento de agregados do sul do Brasil quando se altera o cimento utilizado / Alkali-aggregate reaction: evaluation on the behavior of the aggregates from southern region of Brazil when different types of Portland cements are applied
A reação química que ocorre entre os hidróxidos alcalinos presentes nos poros do concreto e alguns minerais constituintes dos agregados tem causado sérios danos às estruturas. Até o presente momento a prevenção é a melhor forma de evitar que a reação se desencadeie, uma vez que as soluções remediativas ainda necessitam de estudos mais aprofunda
Publicado em: 2007
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6. Nodulos linfoides medulares em pacientes portadores de sindrome mielodisplasicas : incidencia, caracterização morfologica, imunohistoquimica e associação com criterios clinico-laboratoriais, progressão da doença e sobrevida
Myelodysplastic syndromes (MDS) are a heterogeneous group of c10na! disorders characterised by abnormalities in proliferation and maturation of haemopoietic precursors resulting in cytopenias and a preleukaemic state. Bone marrow lYffiphoid nodules (LN) are usually considered to be a physiological feature, closelyrelated to age. In patients with MDS their cl
Publicado em: 2001
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7. Evidence for Molecular Heterogeneity of the Specific Antigen (Fraction-1) of Pasteurella pestis
Fraction-I (F-I) protein, the specific antigen of Pasteurella pestis, appears to be a series of molecular aggregates of identical subunits, all of which have serological reactivity with specific F-I antiserum.
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8. Morphologic appearance of inclusion bodies and their association with the antigenic composition of naturally occurring rabies viruses.
A total of 112 rabies virus-infected skunk brain samples from naturally occurring cases (64 from Missouri, 48 from Kentucky) were code labeled and grouped into two morphologic categories according to the appearance and size of the discrete particles observed by immunofluorescent-antibody staining. The reactivity of the blind-labeled samples was then determin
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9. Physical properties of short- and long-O-antigen-containing fractions of lipopolysaccharide from Escherichia coli 0111:B4.
Aggregates of short- and long-chain O-antigen-containing fractions of lipopolysaccharide were analyzed by electron spin resonance probing to reveal differences in their physical properties. The fluidities of the lipid regions of the two fractions were quite similar, although the long-chain lipopolysaccharide aggregates appeared to be more hydrated as reflect
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10. The molecular chaperone calnexin facilitates folding and assembly of class I histocompatibility molecules.
Calnexin, a membrane protein of the endoplasmic reticulum, is generally thought to function as a molecular chaperone, based on indirect or correlative evidence. To examine calnexin's functions more directly, we reconstituted the assembly of class I histocompatibility molecules in the absence or presence of calnexin in Drosophila melanogaster cells. Calnexin
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11. Structure, composition, and assembly of paracrystalline phycobiliproteins in Synechocystis sp. strain BO 8402 and of phycobilisomes in the derivative strain BO 9201.
The phycobiliproteins of the unicellular cyanobacterium Synechocystis sp. strain BO 8402 and its derivative strain BO 9201 are compared. The biliproteins of strain BO 8402 are organized in paracrystalline inclusion bodies showing an intense autofluorescence in vivo. These protein-pigment aggregates have been isolated. The highly purified complexes contain ph
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12. Electron microscopic localization of receptors for aggregated beta 2-microglobulin on the surface of beta-hemolytic streptococci.
The presence and location of receptors for aggregated human beta 2-microglobulin (beta 2m) on the surface of group A, C, and G streptococci were studied by electron microscopic techniques. Ferritin-conjugated aggregates of human beta 2m were used in direct binding experiments. Ferritin-conjugated antibodies against beta 2m were employed in a two-step indirec