Silica and its Peculiarities

Gomes, Luana da Silva; Souza, Marcos C. de; Furtado, Antonia Carlene Rodrigues

doi:10.21577/1984-6835.20180072

Cited by 9 publications

(6 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The wells that compose cluster 1 of the first component regarding the rainy period have depths that vary between 10 and 685 meters and obtain water from the Dunas, Barreiras, and Açu aquifers, the latter of which can only be reached by wells that are at least 200 meters deep (western portion of the area). The waters from these wells are characterized by low ionic concentrations associated with the sandy constitution of the aquifers, predominantly composed of SiO 2 (Figure 4), which has low solubility in normal temperature conditions but higher solubility in geothermal groundwater conditions (Gomes, Furtado & Souza 2018). The low salt concentrations also indicate a lower marine influence in these wells.…”

Section: Hierarchical Cluster Analysis (Hca)mentioning

confidence: 99%

Multivariate Statistics Applied to the Identification of Compositional Control Parameters for Groundwater

De Araújo,

Freire,

Cavalcante

et al. 2024

Anu. Inst. Geociênc.

View full text Add to dashboard Cite

The objective of the present study was to identify the most influent parameters in the composition of groundwater in the municipality of Icapuí, Ceará - Brazil, seeking correlations with the composition of the percolating aquifer formations that can be associated with the sources of these components. For this purpose, multivariate statistical techniques were applied by means of a Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). The PCA allowed a reduction of physicochemical parameters and determined the two components responsible for approximately 86% of total variance in the data for both sampling periods (rainy and dry). The first component is represented by variables that indicate natural rock weathering processes, and the second comprises seasonality and pollution indicators. Samples were also correlated through HCA according to compositional similarities, which were associated with possible natural or human sources.

show abstract

Section: Hierarchical Cluster Analysis (Hca)mentioning

confidence: 99%

Multivariate Statistics Applied to the Identification of Compositional Control Parameters for Groundwater

De Araújo,

Freire,

Cavalcante

et al. 2024

Anu. Inst. Geociênc.

View full text Add to dashboard Cite

show abstract

“…Among the minerals, there is also zeolite, which in addition to silica and oxygen, has aluminum in its composition. [108,110] Silica is commonly used as an additive in polymeric foams, and its incorporation can influence the properties of foams. In the study by Haibach et al polymer foams with high porosity were produced, and the influence of the addition of silica particulates on the properties was investigated.…”

Section: Nucleating Agentmentioning

confidence: 99%

“…Among the minerals, there is also zeolite, which in addition to silica and oxygen, has aluminum in its composition. [ 108,110 ]…”

Section: Developmentmentioning

confidence: 99%

Starch Foams and Their Additives: A Brief Review

Figueiró,

Calcagno,

Santana

2023

Starch Stärke

View full text Add to dashboard Cite

Short‐life packaging has been contributing to the increased consumption of polymers. Expanded polystyrene (EPS) is a material that is widely used in disposable packaging, however, its residue occupies a large volume, is difficult to degrade, and its recycling is expensive. That's why the interest in looking for a material of natural and biodegradable origin that can be an alternative to petrochemical‐based polymers. One possibility would be starch, which is a natural and biodegradable polysaccharide and can be extracted from different sources. However, natural starch does not have good properties for commercial application, requiring chemical modifications and/or the incorporation of additives. This article carried out a compilation of current studies that work on the development of packaging, whether film or foams, based on plasticized starch (TPS), and analyzes the influence of the incorporation of additives or treatments carried out in the starch. The blowing agent decreases foam density, cell size, and increases cell density. Incorporation of glycerol in starch foams increases the gelatinization temperature, decreases viscosity and resistance to expansion. The surfactant decreases the density and moisture absorption of the foam, the nucleating agent acted by increasing the mechanical strength and density of the foam, and decreases the absorption of water.

show abstract

“…There are also zeolites, which are minerals formed by aluminum (Al), silicon (Si), and oxygen (O). [31,32] There are some research in the literature about the influence of the incorporation of inorganic fillers on the properties of starch-based foams. Talc is a silicate used as an additive in foams, however its application decreased the mechanical strength of foams.…”

Section: Introductionmentioning

confidence: 99%

Effect of Silica Content on Cellular Structural and Hygroscopicity of Modified Cassava Starch Foam

et al. 2023

View full text Add to dashboard Cite

The grow in polymer production is influenced by the high demand from the packaging sector. Expanded polystyrene (EPS) is one of these materials that is widely used in disposable packaging, however, generating waste that occupies a large volume, besides being of difficult degradation. Starch, a naturally occurring and biodegradable polysaccharide, would be an alternative in the search for a renewable source material. However, starch foams have some limitations related to their hygroscopicity. The objective of this study wasto analyze the influence of silica content (1, 2 and 3%) on the cell structure and surface hygroscopicity of cassava starch foams. The foams containing starch, glycerol and water wereproduced by thermo‐compression molding. Results showed that, at lower contents, silica acted predominantly as a nucleating agent, generating smaller cells in the foam. At the higher silica content, it played a more efficient role in reducing the affinity of the starch for water. The formulation with 2% silica showed the highest density (0.232 g/cm3), impact strength (2067 J/m2) and contact angle (84.8°).This article is protected by copyright. All rights reserved

show abstract

Silica and its Peculiarities

Cited by 9 publications

References 53 publications

Multivariate Statistics Applied to the Identification of Compositional Control Parameters for Groundwater

Multivariate Statistics Applied to the Identification of Compositional Control Parameters for Groundwater

Starch Foams and Their Additives: A Brief Review

Effect of Silica Content on Cellular Structural and Hygroscopicity of Modified Cassava Starch Foam

Contact Info

Product

Resources

About