Publications by authors named "K Vojisavljevic"

Developing highly efficient semiconductor metal oxide (SMOX) sensors capable of accurate and fast responses to environmental humidity is still a challenging task. In addition to a not so pronounced sensitivity to relative humidity change, most of the SMOXs cannot meet the criteria of real-time humidity sensing due to their long response/recovery time. The way to tackle this problem is to control adsorption/desorption processes, i.

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In the present work, a biomaterial (SBA-16/HA) based on the growth of hydroxyapatite (HA) particles within an organized silica structure SBA-16 (Santa Barbara Amorphous-16) was developed to evaluate its application to act as a porous microenvironment promoting attachment and viability of human dental pulp stem cells of healthy deciduous teeth (SHED). First, SHED were isolated and their phenotypes were evaluated by flow cytometry. The samples of SBA-16/HA were characterized by X-ray diffraction (XRD), small and wide angle X-ray scattering (SWAXS), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) equipped with energy dispersive spectra detector (EDS).

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In this study, we report on the acid-catalysed synthesis of La(9.33)Si(6)O(26) from lanthanum nitrate or acetate and silicon ethoxide (TEOS) in the ethanol solvent, upon the transition from liquid to amorphous and crystalline phases. The similarity of the Fourier transform infrared spectra of the lanthanum-salt solutions and lanthanum-silicon sols indicates that the lanthanum environment is not changed in the reaction of the La-salt with TEOS.

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Zinc oxide nanopowders were synthesized by the sol-gel method from an ethanol solution of zinc acetate dihydrate. Detailed structural and microstructural investigations were carried out using x-ray diffraction, Raman spectroscopy, thermogravimetric and differential thermal analyses, as well as high-resolution transmission electron microscopy (TEM) and field-emission scanning electron microscopy. The intermediate compound of the reaction was layered zinc hydroxide acetate that further transforms into hexagonally shaped ZnO crystalline nanoplates (d(m) = 4 nm), which aggregate into larger spherical particles.

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In this paper, changes of microstructural characteristics of disperse systems during mechanical activation of zinc oxide (ZnO) have been investigated. ZnO powder was activated by grinding in a planetary ball mill in a continuous regime in air during 300 min at the basic disc rotation speed of 320 rpm and rotation speed of bowls of 400 rpm but with various balls-to-powder mass ratios. During ball milling in a planetary ball mill, initial ZnO powder suffered high-energy impacts.

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