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Polyacrylonitrile (PAN)/sodium silicate (SS) nanocomposite was prepared via nonconventional emulsion method using an in situ developed transition metal complex Cu(II)/glycine taking ammonium persulfate (APS) as initiator, with a novel motive of converting hydrophobic homopolymer PAN into hydrophilic nano material via nanotechnology by the inclusion of SS to the homopolymer. UV–visible spectral analysis was carried out which revealed various interactions between the in situ developed complex with other reaction components. The formation of the PAN/SS nanocomposite was confirmed by infrared spectra (IR). Furthermore, as evidenced by transmission electron microscopy (TEM), the composite so obtained was found to have nano scale structure. X‐ray diffraction (XRD) was carried out suggesting that the silicate layers were exfoliated during the polymerization process. An increase in the thermal stability for the developed nanocomposite was recorded by thermogravimetric analysis (TGA). Surprisingly, it was also found that the PAN/SS nanocomposite showed considerable amount of waterabsorbency and was biodegradable as tested by activated sludge and cultured media and further confirmed by scanning electron microscopy (SEM). POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers 相似文献
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Yaseen K.R. Shariff Harish K. Choudhary Vijay Khopkar Ankit Yadav R. Madhusudhana Balaram Sahoo 《Ceramics International》2021,47(10):14907-14912
We report the mechanism involved in sol-gel auto-combustion synthesis of Ba–Sr-hexaferrite (Ba1-xSrxFe12O19; x = 0, 0.25, 0.5, 0.75 and 1, BSFO) ceramic powders through the analysis of the phases evolved during annealing of the as-synthesized powders, along with their structure and morphological studies. The XRD patterns of the as-synthesized samples indicate the formation of barium/strontium monoferrite ((Ba/Sr)Fe2O4) and maghemite (γ-Fe2O3) phases along with a minute amount of hematite (α-Fe2O3) phase. Annealing of these samples facilitates formation of BSFO phase through the solid state reaction between BaFe2O4 and γ-Fe2O3 phase. Interestingly, after annealing the samples with x = 0, 0.5 and 1, at 1000 °C for 2 h, we observed that phase pure Ba–Sr hexaferrite structure forms, but for samples with x = 0.25 and 0.75, high amount of hematite (α-Fe2O3) phase is observed, especially for x = 0.75. The reason associated with this could be the large difference between the ionic radii of Ba2+ and Sr2+ ions occupying the oxygen site. Furthermore, our study on annealing dependent phase evolution confirms that, this difference in ionic radii forbids the formation of a single phase Ba–Sr hexaferrite. The growth of clear hexagonal-shaped plate-like particles with varied particle sizes was observed for all the samples. The particle size variation may be due to the influence of the ionic radii difference on the sinterability of the samples. Our study provides a better understanding of synthesis mechanism of Ba–Sr hexaferrite samples. 相似文献
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Sahoo Sumanta Kumar Behera Akhya Kumar Chandran Ramkumar Mallik Archana 《Journal of Applied Electrochemistry》2020,50(6):673-688
Journal of Applied Electrochemistry - Industrial scale manufacturing with tunable properties of graphene nano-sheets has been a practical concern in many applications. This study focuses on, a... 相似文献
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The present article considers an experimental study of tribological performance of electroless Ni–P coatings and optimization
of tribological test parameters based on the Taguchi method coupled with grey relational analysis. A grey relational grade
obtained from the grey relational analysis is used as performance index to study the behaviour of electroless Ni–P coating
with respect to friction and wear characteristics. Experiments are carried out by utilizing the combination of tribological
test parameters based on L27 Taguchi orthogonal design with three test parameters, viz., load, speed and time. It is observed that all the three test
parameters have significant contribution in controlling the friction and wear behaviour of electroless Ni–P coating. In addition,
the interaction of load and time has significant influence on tribological performance. The surface morphology, composition
and wear mechanism of the coatings are studied with the help of scanning electron microscopy, X-ray diffraction analysis and
energy dispersed X-ray analysis. 相似文献
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Wireless Networks - The advances in hardware manufacturing technologies and wireless communications enabled the evolution of tiny, multi-functional, low-power and resource constrained sensor nodes... 相似文献