Precipitated Silica
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. PRODUCTION AND CHARACTERIZATION OF PRECIPITATED SILICA FROM PALM OIL MILL FLY ASH USING CO2 IMPREGNATION AND MECHANICAL FRAGMENTATION
ABSTRACT In this research, sol-gel precipitation using CO2 impregnation and mechanical fragmentation method was applied to produce precipitated silica from Palm Oil Mill Fly Ash (POMFA). Carbon dioxide (CO2) was used in order to reduce the cost of the process and to enable sodium hydroxide recovery. The precipitation process was done in a stirred temperature
Braz. J. Chem. Eng.. Publicado em: 15/07/2019
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2. Rice husk ash as filler in tread compounds to improve rolling resistance
Abstract In the tire industry carbon black is being replaced by silica as a filler in recent due to the development of “green tires”. Amorphous precipitated silica in combination with a silane coupling agent as a filler in tread compounds can result in fuel savings of 3% to 4% compared to a tire having treads made from compounds with carbon black. This m
Polímeros. Publicado em: 2017-03
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3. Kinetic behavior of the reaction between silica and epoxidized liquid rubber
Abstract The use of epoxidized rubber as compatibilizer in silica-filled rubber compounds has been proposed in literature. However, the investigation of the reaction kinetics between the epoxy groups and the hydroxyl groups at the silica surface is not yet described. It is a difficult task, mainly because of the high dilution of the system due the difficulty
Polímeros. Publicado em: 08/12/2016
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4. Evaluation of the influence of the polymer-filler interaction on compounds based on epoxidized elastomeric matrix and precipitated silica
The introduction of epoxy groups into the main chain of elastomers has emerged as a promising alternative, considering the monitoring of polymer-filler interaction leading to changes in the properties of vulcanizates. The epoxidation reaction (in situ) was chosen to modify elastomers, such as polybutadiene (BR) and copolymer of styrenebutadiene- rubber (SBR)
Publicado em: 2010
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5. Evaluation of the influence of the polymer-filler interaction on compounds based on epoxidized elastomeric matrix and precipitated silica
The introduction of epoxy groups into the main chain of elastomers has emerged as a promising alternative, considering the monitoring of polymer-filler interaction leading to changes in the properties of vulcanizates. The epoxidation reaction (in situ) was chosen to modify elastomers, such as polybutadiene (BR) and copolymer of styrene-butadiene-rubber (SBR)
Polímeros. Publicado em: 2006-06
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6. Efeito de formulações de dentifricios com CaCO3 versus SiO2 na inibição da desmineralização do esmalte dental : estudo in situ
Precipitated ca1cium carbonate (CaCO3) is the main abrasive used in dentifiices comercialized in Brazü. It may reduce bacterial acidogenicity, potentiating the effect of fluoride in the development of dental caries due to its aIkaline and buífering capacities. The effect of CaCO3 on the reduction of enamel demineralization was evaluated by using the short-
Publicado em: 2000
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7. Separação e caracterização de oleos provenientes da liquefação direta do bagaço de cana
In this work we describe our attempts to separate the heavy oil, obtained in the direct liquefaction of sugar cane bagasse with sodium formate/water/argon, using liquid chromatography, distllation and liquid-liquid extraction. Both, the crude oil and the resulting fractions were characterized by Infrared, nuclear magnetic resonance and mass spectrometry, gas
Publicado em: 1986
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8. The Toxicity of Precipitated Silica
The proportion of respirable particles in dust clouds generated from three samples of precipitated silica has been shown to range between one-quarter and one-third by weight.
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9. Limited value of serum holo-transcobalamin II measurements in the differential diagnosis of macrocytosis.
AIM: To study the value of serum holo-transcobalamin II (holo-TCII) measurements in the differential diagnosis of macrocytosis. METHODS: Holo-TCII concentrations were measured in serum samples from 50 healthy non-vegetarian subjects and 30 patients with macrocytosis, using a technique based on the adsorption of holo-TCII with amorphous, precipitated silica.
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10. Correlations between holo-transcobalamin II, holo-haptocorrin, and total B12 in serum samples from healthy subjects and patients.
AIMS--To study the correlations between total vitamin B12(B12), holo-haptocorrin, and holo-transcobalamin II (holo-TCII) concentrations in human sera; the association between reduced holo-TCII concentrations and macrocytosis attributable to B12 deficiency. METHODS--Serum samples from 38 healthy volunteers, 113 patients with normal total serum B12 concentrati
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11. The mitogen-activated protein kinase cascade is activated by B-Raf in response to nerve growth factor through interaction with p21ras.
Nerve growth factor (NGF) activates the mitogen-activated protein (MAP) kinase cascade through a p21ras-dependent signal transduction pathway in PC12 cells. The linkage between p21ras and MEK1 was investigated to identify those elements which participate in the regulation of MEK1 activity. We have screened for MEK activators using a coupled assay in which th