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Sustainable Physiological Adaptation of Humans to Diverse Environment Conditions Using Smart NanoTextiles
Published in Prashansa Sharma, Devsuni Singh, Vivek Dave, Fundamentals of Nano–Textile Science, 2023
Renu Bala Yadav, Vinay Kumar Yadav, Dharam Pal Pathak, Rajesh Arora
Aerogel-incorporated smart textiles are the textile used in space technology for making space suits and space shuttle, cryogenic material, protection suits for high altitude regions, etc. Aerogels are the material having the lightest weight on the Earth and have much exceptional physical properties which make these gels a unique gel. They aligned with covalent bonds and are nanometer in size (1–10 nm diameters) arranged in a space of three-dimensional structures. Aerogel shows extremely low thermal conductivity, low dielectric constant, and high optical transparency physical properties (Bheekhun et al., 2013). Aerogel having low density are compressible and possess good elasticity thus can be used in high range of military appliances such as non-thermal face mask for extremely high temperature range areas, ergonomically designed wearable soles for high altitude trekking, heavy exercises, running, and training, etc.
Hydrogels
Published in Antonio Paesano, Handbook of Sustainable Polymers for Additive Manufacturing, 2022
Hydrogel (HG) is a water-swollen gel comprising a crosslinked 3D polymeric network. Gel is a soft, solid, or solid-like material consisting in two or more components one of which is a liquid present in substantial quantity (Almdal et al. 1993). A well-known example of gel is the food Jell-O™ made by heating gelatin in water, and cooling the mixture. The large, strand-like protein molecules of gelatin wiggle around in hot water, and, as the mixture cools down, they possess less energy, and are less mobile, until eventually they bond together at points along the strands, forming pockets trapping the surrounding liquid and a 3D structure, or matrix, that gives Jell-O™ its structural integrity (Scientific American 1999). Polymers forming hydrogels (HGs) comprise biobased and synthetic polymers, polymer blends, nanocomposites, functional polymers, and cell-laden systems (Li et al. 2020).
Methods of Thin Film Deposition
Published in Fredrick Madaraka Mwema, Tien-Chien Jen, Lin Zhu, Thin Film Coatings, 2022
Fredrick Madaraka Mwema, Tien-Chien Jen, Lin Zhu
The next step involves the drying process to remove the liquid from the product completely. This will lead to shrinkage and densification. The distribution of the porous characteristic in the gel tends to determine how much of the solvent can be removed. After the drying process, a heat treatment method is required to ensure that poly-condensation takes place and that the mechanical characteristics of the final gel-like structure are attractive [132]. The types of gel that result from this process include cryogel, aerogels, ambigels, and xerogels, and all of them have found various applications in the engineering sector [132].
Development of onion oil-based organo-hydrogel for drug delivery material
Published in Journal of Dispersion Science and Technology, 2023
Duygu Alpaslan, Tuba Erşen Dudu, Nahit Aktas
Gels are divided into two categories, hydrogels and organogels, depending on the natural nature of the liquid phase. Hydrogels show that the component immobilized is water; Organogels are types of gels where the immobilized liquid is a hydrophobic component, such as organic solvents or oil. In the more detailed definition of the organogel; It is defined as a gel structure where organic liquids are trapped in three-dimensional gel networks that are reversible by temperature. The ability to contain both hydrophilic and hydrophobic compounds in the structure of organo-hydrogels has also extended the area of use of organogels. Recently, organo-hydrogels have been investigated in a wide range of fields, including chemistry, biotechnology, drug delivery, and pharmaceuticals.[1–5]
Experimental study of using Aerogel insulation for residential buildings
Published in Advances in Building Energy Research, 2022
Mohamed T. Elshazli, Mohammad Mudaqiq, Tao Xing, Ahmed Ibrahim, Brian Johnson, Jinchao Yuan
Aerogel insulation is a most propitious insulation solution, and it was first discovered in 1931 (Abu-Jdayil et al., 2019; Fricke & Tillotson, 1997; Mahadik et al., 2016). It is a dried gel with high porosity and has lower thermal conductivity than air (Abu-Jdayil et al., 2019; Baetens et al., 2011; Jelle, 2011). Aerogels are made by removing liquids from gels, ending up in a material that is more than 90% air. This porous composition of that nanomaterial makes it difficult for the heat to transfer through its structure. As a result, a good, efficient and light-weight insulation is produced (Berardi, 2019). Aerogel is synthetic transparent, highly porous, ultra-light, low density (bulk density 3–20.0 kg/m3), and has a large internal surface area. Moreover, having a unique microstructure (1–20 nm particle diameter and 2–50 nm pore diameter) and a great porosity (can reach up to 90%) result in more desired properties, such as the lowest thermal conductivity, refractive index, sound velocity and dielectric constant of any solid ever tested (Abu-Jdayil et al., 2019; Baetens et al., 2011). Aerogel has thermal conductivity ranging from 10 to 20 mW/(m.K) at ambient pressure. Aerogels have a relatively high compressive strength, and a very low tensile strength which make them a fragile brittle material (Abu-Jdayil et al., 2019; Baetens et al., 2011). The tensile strength could be increased by the incorporation of a carbon fibre matrix.
Gelation-based visual detection of analytes
Published in Soft Materials, 2019
Wangkhem Paikhomba Singh, Rajkumar Sunil Singh
Design of new small-molecule gelators and predicting their gel-forming ability is challenging and mostly driven by empirical approaches (4,5). Till now, there are several reports of small-molecule gelators with a wide range of structures and functionalities. These include amino acid derivatives, amphiphilic molecules, alkanes, ureas derivatives, nucleobase derivatives, poly-aromatics, fatty acids, carbohydrate derivatives, steroids, dendrimers, porphyrins, and others (6–10). Many applications for gels have been reported including drug delivery, biomaterials, tissue engineering, organic electronic devices, gel electrolytes, nanoreactors, catalysts, visual sensors, and others (11–15). Nowadays, there is a great deal of interest in developing stimuli-responsive gels. Stimuli such as light, acid-base, enzymes, ions, ultrasound, oxidation-reduction, and mechanical stress have been used to manipulate the properties of gels (16,17). These stimuli-responsive gels serve as useful platforms for developing gelation-based visual sensors of various analytes. It may be mentioned that the use of gels for visual detection work of analytes is a fairly new phenomenon.