silica  coated magnetite  nanoparticles were  covalent  grafted with  3-aminopropyl trimethoxysilane  to give aptscmnps. reaction of  the resulted nanomaterial with 4-formyl benzo-12-crown-4 ether afforded fb12c4/aptsmnps  nanocomposite  material  in  which  the  crown ether  moiety  was  attached  through  propyl  chain  spacer. characterization of  the prepared nanocomposite was performed wit...

The resolution of coherent and incoherent imaging systems is usually evaluated in terms of classical resolution criteria, such as Rayleigh's. Based on these criteria, incoherent imaging is generally concluded to be 'better' than coherent imaging. However, this paper reveals some misconceptions in the application of the classical criteria, which may lead to wrong conclusions. Furthermore, it is ...

The basic principles and methods of off-axis electron holography are presented and illustrated by means of three examples related to its application in high resolution electron microscopy and the investigation of electric and magnetic fields in thin specimens.

Transmission electron microscope (TEM) has emerged as a very powerful tool for probing the structure of metals and alloys because of its capability to provide morphological information, crystallographic details, and chemical composition of phases distributed on a very fine scale in a given microstructure. Convergent beam electron diffraction, nano or micro beam diffraction and selected area dif...

High-resolution transmission electron microscopy (HRTEM) has been widely and effectively used for analyzing crystal structures and lattice imperfections in various kinds of advanced materials on an atomic scale. This is especially the case for high Tc superconductors (HTSCs). The most characteristic feature in crystal structures of HTSCs is that there is a common structural element, a CuO2 plan...