Nanoparticles have been an area of active research in recent years due to their properties, which can be greatly different from the bulk. In this work, we study the sintering of TiO2 nanoparticles using molecular dynamics simulations. Such sintering occurs in flame reactors where nanotitania is prepared via the chloride process. Decrease in free energy due to reduction in surface area is the ma...

The CuO modified (Na0.52K0.48)NbO3 (NKN) piezoelectric ceramics were prepared by a solid-state reaction method. On the one hand, CuO doping can improve the densification behavior and simultaneously promote the grain growth, however, has little effect on the Curie temperature. On the other hand, the mechanical quality factor Qm obviously increases, the dielectric loss tanδ decreases, and the pie...

In this study, synchrotron radiation computed tomography was applied to investigate the mechanisms of titanium powder microwave sintering in situ. On the basis of reconstructed images, we observed that the sintering described in this study differs from conventional sintering in terms of particle smoothing, rounding, and short-term growth. Contacted particles were also isolated. The kinetic curv...

A facile one-pot aqueous solution method has been developed for the fast and straightforward synthesis of SnTe nanoparticles in more than ten gram quantities per batch. The synthesis involves boiling an alkaline Na₂SnO₂ solution and a NaHTe solution for short time scales, in which the NaOH concentration and reaction duration play vital roles in controlling the phase purity and particle size, re...

The thermal decomposition of synthetic a-FeOOH in air has becn studied by X~ray powder diffraction (XRD), IR spectroscopy. transmission electron microscopy, and nitrogen adsorption. Three stages may be differentiated during the course ofthe reaction: (i) 200-250°C; slit-shaped micropores of nearly equal width, about 1.4 nm, are formed along the elongated direction of the lath-shaped acicular mí...

Despite the fact that particle sintering is one of the most common events leading to the deactivation of metal nanoparticle (NP) catalysts, there is a paucity of studies investigating potential routes for the regeneration of smaller, catalytically active nanoparticles from larger particles formed after repeated catalytic cycles. Here, we reveal a simple yet elegant technique for the 'redispersi...

Enhancing the charge transfer process in nanocrystal sensitized solar cells is vital for the improvement of their performance. In this work we show a means of increasing photo-induced ultrafast charge transfer in successive ionic layer adsorption and reaction (SILAR) CdS-TiO2 nanocrystal heterojunctions using pulsed laser sintering of TiO2 nanocrystals. The enhanced charge transfer was attribut...

The biological effects of nanohydroxyapatites and its cell toxicity have been studied using the MTT and ALP method, infrared spectrum of absorption and electrophoresis method, respectively. The nanohydroxyapatites are prepared and made by using sol-gel method, in which the parameters of process and reaction are controlled as: pH > 9, Ca/P = 1.67, sintering temperature of 1100 degrees C and sint...

The laser sintering process of multi-component powder W/Cu is simulated by ANSYS software based on the factors of radiation, convection and thermal physical parameters on temperature. The laser power and scanning velocity which are the key process parameters to affect directly in sintering molding are studied in paper. The results show that when the scanning velocity is constant, the sintering ...

Until 2000 almost all research in the microwave sintering area was confined to non-metallic materials. However, after the first report by Penn State in 1999 on full sintering of steel powders in microwave, now in the last few years there has been increasing interest in applying microwave energy for processing of variety of metallic materials. The present study is an extension of this work and r...