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Abhishek Nigam Sheetal Saini Ambak Kumar Rai S.J. Pawar 《Ceramics International》2021,47(14):19515-19525
In this study, MgO nanoparticles were successfully fabricated and incubated inside ZnO NPs to form MgO/ZnO nanocomposite for biomedical applications. The x-ray diffraction analysis of MgO, ZnO, and MgO/ZnO has shown the single-phase x-ray diffraction patterns through X'pert High score. The crystallite sizes were calculated as 18 nm, 42 nm, and 53 nm, respectively. The average particle size of MgO, ZnO, and MgO/ZnO nanopowders depicted from secondary electron images of field emission electron microscopy were 56 nm, 400 nm, and 450 nm, respectively. The presence of MgO NPs inside ZnO NPs was confirmed by transmission electron microscopy. The elemental dispersive spectroscopy of MgO, given the peaks of oxygen and magnesium, also showed only zinc and oxygen peaks in ZnO, which confirms no other impurities in MgO and ZnO powders. The elemental analysis of MgO/ZnO nanocomposite showed the peaks of Zinc and Oxygen, along with a tiny peak of Mg. The photoluminescence and UV–vis spectroscopy revealed the absorbance fluorescence limit of the nanomaterials. Fourier transform infrared spectroscopy confirmed the several groups present in the nanocomposite. The biocompatibility of MgO, ZnO, and MgO/ZnO was observed with human peripheral blood mononuclear cells. The cytotoxicity studies were also performed against human cancer (liver and breast) cell lines. The MgO, ZnO, and MgO/ZnO exhibited the antimicrobial properties against Escherichia coli and Staphylococcus aureus. 相似文献
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Wireless Personal Communications - IoT-based smart farming techniques have come up as one of the solutions to tackle the effect of climate change, water scarcity, etc. which are the prime reason... 相似文献
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Neural Processing Letters - The uncertainty caused mainly by the deficiency of precision and data, artificial/human-made errors, information accessed from expert opinions or very miniature size of... 相似文献
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Manik Chandra Biswas Samit Chakraborty Abhishek Bhattacharjee Zaheeruddin Mohammed 《Advanced functional materials》2021,31(19):2100257
Shape memory materials (SMMs) in 3D printing (3DP) technology garnered much attention due to their ability to respond to external stimuli, which direct this technology toward an emerging area of research, “4D printing (4DP) technology.” In contrast to classical 3D printed objects, the fourth dimension, time, allows printed objects to undergo significant changes in shape, size, or color when subjected to external stimuli. Highly precise and calibrated 4D materials, which can perform together to achieve robust 4D objects, are in great demand in various fields such as military applications, space suits, robotic systems, apparel, healthcare, sports, etc. This review, for the first time, to the best of the authors’ knowledge, focuses on recent advances in SMMs (e.g., polymers, metals, etc.) based wearable smart textiles and fashion goods. This review integrates the basic overview of 3DP technology, fabrication methods, the transition of 3DP to 4DP, the chemistry behind the fundamental working principles of 4D printed objects, materials selection for smart textiles and fashion goods. The central part summarizes the effect of major external stimuli on 4D textile materials followed by the major applications. Lastly, prospects and challenges are discussed, so that future researchers can continue the progress of this technology. 相似文献
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Effects of bentonite concentration on morphology and permeation characteristics of bentonite-doped polysulfone membranes were investigated. Solubility sphere for bentonite was constructed to estimate its solubility parameter. Thermodynamic modeling of phase inversion of this system was carried out using Flory–Huggins theory. The trade-off between thermodynamic and kinetic parameters was used to predict the membrane morphology for bentonite concentration varying from 0 to 5 wt %. The porosity of bentonite-doped membranes decreased up to 3 wt % that increased thereafter. Morphological analysis showed dense cross section with finger-like macrovoids at 3 wt % beyond which it changed to honeycomb structure with large circular voids. Permeability of 3 wt % membrane was the lowest (5.6 × 10−12 m/Pa s) with 95% bovine serum albumin rejection. Contact angle of the membranes decreased from 83 to 66° with bentonite addition making the membrane more hydrophilic. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48450. 相似文献
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