Showing 2 results for M. Pirhadi Tavandashti
M. Pirhadi Tavandashti, M. Zandrahimi, B. Akbari,
Volume 6, Issue 1 (winter 2009 2009)
Abstract
Abstract: Nanoparticles exhibit a high reactivity and strong tendency towards agglomeration. In this study, aluminum
oxide (alumina) nanoparticles were characterized by gas adsorption (BET), transmition electron microscopy (TEM)
and photon correlation spectroscopy (PCS) techniques to assess the agglomeration of the particles. There is a good
correlation between the BET and TEM measurements but PCS was larger in the mean and median size and with a
degree of agglomerates being detected. Some agglomeration was evident, but most of the particles existed as discrete
objects as observed in the (HR) TEM images which were in good agreement with the agglomeration factor.
B. Akbari, M. Pirhadi Tavandashti, M. Zandrahimi,
Volume 8, Issue 2 (spring 2011 2011)
Abstract
Abstract: Most properties of nanoparticles are size-dependent. In fact, the novel properties of nanoaprticles do not prevail until the size has been reduced to the nanometer scale. The particle size and size distribution of alumina nanoparticle, as a critical properties, have been determined by transmission electron microscopy (TEM), photon correlation spectroscopy (PCS), surface area analysis (BET) and x-ray diffraction peak broadening analysis. The particle size was found to be in the range of 5-95nm. Cumulative percentage frequency plot of the data extracted form TEM images indicates that particle size distribution obeys the log-normal function. The TEM images also reveal that particles are spherical in shape and loosely agglomerated. Comparing of the XRD and TEM results shows that the particles are single-crystal. The HRTEM images also verify that the particles have a single-crystal nature. In comparison, there is a good correlation between the BET, XRD and TEM measurements other than PCS that is sensitive to the presence of the agglomerates.
