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Application of Biomaterials and Finite Element Analysis (FEA) in Nanomedicine and Nanodentistry
Published in Sarhan M. Musa, Computational Finite Element Methods in Nanotechnology, 2013
Andy H. Choi, Jukka P. Matinlinna, Richard C. Conway, Besim Ben-Nissan
A sol, by definition, is a suspension of colloidal particles in a liquid [47]. A sol differs from a solution in that a sol is a two-phase, solid–liquid system, whereas a solution is a single-phase system. Colloidal particles can be in the approximate size range of 1–1000 nm; for this reason, gravitational forces on these colloidal particles are negligible and interactions are dominated by short-range forces such as van der Waals forces and surface charges. Diffusion of the colloids by Brownian motion leads to a low-energy arrangement, thus imparting stability to the system [48]. The stability of the sol particles can be modified by reducing their surface charge. If the surface charge is significantly reduced, then gelation is induced and the resultant product is able to maintain its shape without the assistance of a mould.
Surface Forces in Nanostructures
Published in Victor M. Starov, Nanoscience, 2010
The authors of Ref. [67] performed dynamic light-scattering measurements of the Brownian diffusion coefficients of monodispersed silica sols Ludox-SM (particle radius r = 19 nm) and Syton- W50 (r = 69 nm) before and after adsorption of polyethylene oxide (PEO) with a molecular weight of 4 × 10. They used the results obtained for estimation of the thickness of adsorption layers. Sols remained stable at low electrolyte concentrations because of electrostatic repulsion forces. However, at NaCl concentrations of 10−2 mol L−1, when the Debye length became smaller than the length of an unfolded PEO molecule, flocculation of the sols took place, even in the presence of small amounts of the polymer, due to linkage of two particles by one macromolecule (so-called “bridging”). Sols became stable again with increase in PEO concentration and formation of a full adsorption layer owing to steric repulsion between the particles.
Probing the Molecular Details of the Surfaces of Powders and Fibers Using Infrared Spectroscopy
Published in Michel Nardin, Eugène Papirer, Powders and Fibers, 2006
The sol–gel process is a versatile solution process for making ceramic and glass materials. Due to the low temperature requirements and ease of processing, sol–gel techniques have become widely used for the fabrication of many types of ceramics and glasses. In general, the sol–gel process involves the transition of a system from a liquid sol into a solid gel phase. A sol is defined as a colloidal suspension of solid particles in a liquid. A gel is formed by condensing or growing a sol to the point where one polymerized molecule reaches macroscopic dimensions so that it extends throughout the solution.72 By applying the sol–gel process, it is possible to fabricate ceramic or glass materials in a wide variety of forms: ultra-fine or spherical-shaped powders, thin-film coatings, ceramic fibers, microporous inorganic membranes, monolithic ceramics and glasses, or extremely porous aerogel materials.72 An overview of the sol–gel process is presented in Figure 4.7.
Detail review on chemical, physical and green synthesis, classification, characterizations and applications of nanoparticles
Published in Green Chemistry Letters and Reviews, 2020
Irfan Ijaz, Ezaz Gilani, Ammara Nazir, Aysha Bukhari
Sol–gel method is a combination of two words sol and gel. Sol is a colloid formed from solid particles suspended particles in continuous liquid. Gel is a solid macro-molecule which is dissolved in solvent. Due to simplicity, sol–gel method is the most preferred bottom-up method for the synthesis of nanoparticles. It is the method in which suitable chemical solution act as precursor. The typical precursors are metal oxide and chloride used in sol–gel method (91). By using different methods such as stirring, sonication and shaking, the precursor is dispersed in host liquid. The resultant solution consists of solid phase and liquid which is separated by using different techniques such as filtration, sedimentation and centrifugation to recover the nanoparticles show in Figure 12.
Producing a thin coloured film on stainless steels – a review. Part 2: non-electrochemical and laser processes
Published in Transactions of the IMF, 2023
G. T. Alliott, R. L. Higginson, G. D. Wilcox
Sol–gel is a chemical synthesis method of producing metastable solids from molecular precursors in a liquid medium via hydrolysis and condensation reactions.25,26 A sol is a liquid containing colloidal particles in suspension. A gel consists of a continuous liquid phase supported by a porous, solid network that is usually the consequence of covalent bonds forming between sol particles.26
A review on multifunctional nanotechnological aspects in modern textile
Published in The Journal of The Textile Institute, 2022
Prashant D. Sarvalkar, Shubham D. Barawkar, Omkar S. Karvekar, Pandurang D. Patil, Saurabh R. Prasad, Kiran Kumar Sharma, Neeraj R. Prasad, Rajiv S. Vhatkar
Sol: A colloidal suspension of solid particles in a liquid with a small dispersed phase (1–1000 nm) is known as sol. Hydrolysis and condensation are two processes in the formation of sol. Hydrolysis is the process of breaking water molecules into OH- and H+ ions. The following is the general hydrolysis reaction (Eq. 1)