Surfactant-Synthesized PDMS/Silica Nanomaterials Improve Robustness and Stain Resistance of Carbonate Stone

2011 ◽  
Vol 115 (30) ◽  
pp. 14624-14634 ◽  
Author(s):  
Juan F. Illescas ◽  
María J. Mosquera
Keyword(s):  
Silica Nanomaterials ◽  
Stain Resistance

The Synthesis and Application of Functionalized Mesoporous Silica SBA-15 as Heterogeneous Catalyst in Organic Synthesis

2020 ◽  
Vol 24 ◽  
Author(s):  
Ghodsi Mohammadi Ziarani ◽  
Shima Roshankar ◽  
Fatemeh Mohajer ◽  
Alireza Badiei
Keyword(s):  
Mesoporous Silica ◽  
Heterogeneous Catalyst ◽  
Organic Synthesis ◽  
Lewis Acid ◽  
Heterogeneous Catalysts ◽  
Organic Transformations ◽  
Functionalized Mesoporous Silica ◽  
Silica Nanomaterials ◽  
Wide Range ◽  
Target Molecules

Abstract:: Mesoporous silica nanomaterials provide an extraordinary advantage for making new and superior heterogeneous catalysts because of their surface silanol groups. The functionalized mesoporous SBA-15, such as acidic, basic, BrÖnsted, lewis acid, and chiral catalysts, are used for a wide range of organic synthesis. The importance of the chiral ligands, which were immobilized on the SBA-15, was mentioned in this review to achieve chiral products as valuable target molecules. Herein, their synthesis and application in different organic transformations are reviewed from 2016 till date 2020.

scholarly journals Size and surface modification of silica nanoparticles affect the severity of lung toxicity by modulating endosomal ROS generation in macrophages

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Masahide Inoue ◽  
Koji Sakamoto ◽  
Atsushi Suzuki ◽  
Shinya Nakai ◽  
Akira Ando ◽  
...  
Keyword(s):  
Immune Response ◽  
Surface Modification ◽  
Lung Injury ◽  
Cellular Uptake ◽  
Intratracheal Instillation ◽  
Chemical Properties ◽  
Raw264.7 Cells ◽  
Neutrophilic Infiltration ◽  
Silica Nanomaterials ◽  
Physico Chemical

Abstract Background As the application of silica nanomaterials continues to expand, increasing chances of its exposure to the human body and potential harm are anticipated. Although the toxicity of silica nanomaterials is assumed to be affected by their physio-chemical properties, including size and surface functionalization, its molecular mechanisms remain unclear. We hypothesized that analysis of intracellular localization of the particles and subsequent intracellular signaling could reveal a novel determinant of inflammatory response against silica particles with different physico-chemical properties. Results We employed a murine intratracheal instillation model of amorphous silica nanoparticles (NPs) exposure to compare their in vivo toxicities in the respiratory system. Pristine silica-NPs of 50 nm diameters (50 nm-plain) induced airway-centered lung injury with marked neutrophilic infiltration. By contrast, instillation of pristine silica particles of a larger diameter (3 μm; 3 μm-plain) significantly reduced the severity of lung injury and neutrophilic infiltration, possibly through attenuated induction of neutrophil chemotactic chemokines including MIP2. Ex vivo analysis of alveolar macrophages as well as in vitro assessment using RAW264.7 cells revealed a remarkably lower cellular uptake of 3 μm-plain particles compared with 50 nm-plain, which is assumed to be the underlying mechanism of attenuated immune response. The severity of lung injury and neutrophilic infiltration was also significantly reduced after intratracheal instillation of silica NPs with an amine surface modification (50 nm-NH2) when compared with 50 nm-plain. Despite unchanged efficacy in cellular uptake, treatment with 50 nm-NH2 induced a significantly attenuated immune response in RAW264.7 cells. Assessment of intracellular redox signaling revealed increased reactive oxygen species (ROS) in endosomal compartments of RAW264.7 cells treated with 50 nm-plain when compared with vehicle-treated control. In contrast, augmentation of endosomal ROS signals in cells treated with 50 nm-NH2 was significantly lower. Moreover, selective inhibition of NADPH oxidase 2 (NOX2) was sufficient to inhibit endosomal ROS bursts and induction of chemokine expressions in cells treated with silica NPs, suggesting the central role of endosomal ROS generated by NOX2 in the regulation of the inflammatory response in macrophages that endocytosed silica NPs. Conclusions Our murine model suggested that the pulmonary toxicity of silica NPs depended on their physico-chemical properties through distinct mechanisms. Cellular uptake of larger particles by macrophages decreased, while surface amine modification modulated endosomal ROS signaling via NOX2, both of which are assumed to be involved in mitigating immune response in macrophages and resulting lung injury.

scholarly journals Fabrication of Silica Nanomaterials Reflecting Morphological Transition of DNA Mediated by a Silane-appended Ionic Liquid

2011 ◽  
Vol 40 (5) ◽  
pp. 435-437 ◽  
Author(s):  
Kojiro Shimojo ◽  
Hisayoshi Mitamura ◽  
Tsuyoshi Mouri ◽  
Hirochika Naganawa
Keyword(s):  
Ionic Liquid ◽  
Morphological Transition ◽  
Silica Nanomaterials

scholarly journals Microfluidics-mediated self-template synthesis of anisotropic hollow ellipsoidal mesoporous silica nanomaterials

2017 ◽  
Vol 5 (8) ◽  
pp. 584-590 ◽  
Author(s):  
Nanjing Hao ◽  
Yuan Nie ◽  
Amogha Tadimety ◽  
Andrew B. Closson ◽  
John X. J. Zhang
Keyword(s):  
Mesoporous Silica ◽  
Template Synthesis ◽  
Silica Nanomaterials

scholarly journals A Review of Composite Phase Change Materials Based on Porous Silica Nanomaterials for Latent Heat Storage Applications

Molecules ◽  
2021 ◽  
Vol 26 (1) ◽  
pp. 241
Author(s):  
Raul-Augustin Mitran ◽  
Simona Ioniţǎ ◽  
Daniel Lincu ◽  
Daniela Berger ◽  
Cristian Matei
Keyword(s):  
Phase Change ◽  
Latent Heat ◽  
Phase Change Materials ◽  
Heat Storage ◽  
Porous Silica ◽  
Lessons Learned ◽  
High Porosity ◽  
Storage Materials ◽  
Silica Nanomaterials ◽  
Heat Storage Materials

Phase change materials (PCMs) can store thermal energy as latent heat through phase transitions. PCMs using the solid-liquid phase transition offer high 100–300 J g−1 enthalpy at constant temperature. However, pure compounds suffer from leakage, incongruent melting and crystallization, phase separation, and supercooling, which limit their heat storage capacity and reliability during multiple heating-cooling cycles. An appropriate approach to mitigating these drawbacks is the construction of composites as shape-stabilized phase change materials which retain their macroscopic solid shape even at temperatures above the melting point of the active heat storage compound. Shape-stabilized materials can be obtained by PCMs impregnation into porous matrices. Porous silica nanomaterials are promising matrices due to their high porosity and adsorption capacity, chemical and thermal stability and possibility of changing their structure through chemical synthesis. This review offers a first in-depth look at the various methods for obtaining composite PCMs using porous silica nanomaterials, their properties, and applications. The synthesis and properties of porous silica composites are presented based on the main classes of compounds which can act as heat storage materials (paraffins, fatty acids, polymers, small organic molecules, hydrated salts, molten salts and metals). The physico-chemical phenomena arising from the nanoconfinement of phase change materials into the silica pores are discussed from both theoretical and practical standpoints. The lessons learned so far in designing efficient composite PCMs using porous silica matrices are presented, as well as the future perspectives on improving the heat storage materials.

Synergistic regulation of silica nanomaterials and earthworms on maize root metabolite profiles via promoting soil Si bioavailability

2021 ◽  
Author(s):  
Weisheng Ma ◽  
Le Yue ◽  
Feiran Chen ◽  
Haihua Ji ◽  
Ningke Fan ◽  
...  
Keyword(s):  
Soil Fauna ◽  
Maize Root ◽  
Silica Nanomaterials ◽  
Metabolite Profiles ◽  
Synergistic Regulation ◽  
Rhizosphere Processes

Silicon (Si) acquisition by plants are stimulated by root-associated rhizosphere processes which are usually mediated by nanomaterials and soil fauna. In this study, 10 mg kg-1 silica nanomaterials (SiO2 NMs)...

Structure-property interplay of asymmetric membranes comprising of soft polydimethylsiloxane chains and hard silica nanomaterials

Polymer ◽  
2019 ◽  
Vol 160 ◽  
pp. 30-42 ◽  
Author(s):  
Ankit M. Kansara ◽  
Pradeep K. Prajapati ◽  
Vinod K. Aswal ◽  
Puyam S. Singh
Keyword(s):  
Structure Property ◽  
Asymmetric Membranes ◽  
Silica Nanomaterials
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