An analytical electron microscopy investigation of municipal solid waste incineration bottom ash

1998 ◽  
Vol 13 (1) ◽  
pp. 28-36 ◽  
Author(s):  
James E. Krzanowski ◽  
T. Taylor Eighmy ◽  
Bradley S. Crannell ◽  
J. Dykstra Eusden
Keyword(s):  
Electron Microscopy ◽  
Metal Oxides ◽  
Amorphous Material ◽  
Analytical Electron Microscopy ◽  
Bottom Ash ◽  
Waste Incineration ◽  
High Density ◽  
Leaching Behavior ◽  
Microscopy Investigation ◽  
Analytical Electron

Incinerator bottom ash samples have been characterized using analytical electron microscopy (AEM) techniques, including electron diffraction, energy dispersive spectroscopy, and electron energy loss spectroscopy. The samples were first separated by magnetic properties and density. Three resulting fractions were examined: the magnetic, high-density (MHD) fraction, the nonmagnetic/high-density (NMHD) fraction, and the nonmagnetic, low-density (NMLD) fraction. Examination of these samples revealed a variety of submicron microstructural features. For the MHD fraction, metal oxides, iron silicates, aluminum silicates, and calcium phosphate compounds were found in addition to amorphous material. The NMHD fraction contained elements similar to the MHD fraction but had more amorphous material; crystalline silicates were less common. Compounds such as MgO and chloroapatite were also found. The NMLD fraction contained SiO2 and numerous metal oxides. The results of some of these analyses were used to model leaching behavior of the ash. Based on the AEM results, three mineral phases were chosen as candidates for aqueous geochemical thermodynamic equilibrium modeling of pH-dependent leaching: chromite, chloroapatite, and zincite. In two of these three cases (chromite, chloroapatite), the selected mineral phase provided excellent agreement with the experimentally observed leaching behavior. AEM was shown to be a useful tool for elucidating mineralogy of complex environmental samples.

scholarly journals Analytical Electron microscopy Investigation of Au/TiO2 Thin Films Deposited on the Glass Substrate

2013 ◽  
Vol 19 (S2) ◽  
pp. 1498-1499
Author(s):  
M. Kawasaki ◽  
M.-J. Chen ◽  
J.-R. Yang ◽  
W.-A. Chiou ◽  
M. Shiojiri
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Glass Substrate ◽  
Analytical Electron Microscopy ◽  
Tio2 Thin Films ◽  
Microscopy Investigation ◽  
Electron Microscopy Investigation ◽  
Analytical Electron

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

High-Resolution Analytical Electron Microscopy Investigation of Metastable Tetragonal Phase Stabilization in Undoped, Sol-Gel Derived Zirconia Nanoceramics

2003 ◽  
Vol 788 ◽  
Author(s):  
Vladimir P. Oleshko ◽  
James M. Howe ◽  
Satyajit Shukla ◽  
Sudipta Seal
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Sol Gel ◽  
Analytical Electron Microscopy ◽  
Microscopy Investigation ◽  
Electron Microscopy Investigation ◽  
Analytical Electron ◽  
20 Nm ◽  
Electron Energy Loss ◽  
Hydrolysis Of

ABSTRACTThe mechanisms underlying stabilization of the metastable tetragonal (t)-phase in sol-gel derived, nanocrystalline ZrO2 were studied by high-resolution analytical electron microscopy, utilizing parallel electron-energy loss (PEEL) and energy-dispersive X-ray spectroscopies. The powders were synthesized by hydrolysis of Zr (IV) n-propoxide at ratios of molar concentration of water to Zr n-propoxide, R=5 and 60, respectively, followed by calcination at 400°C. Dense particles of the as-precipitated ZrO2 (R=5) revealed 4–11 nm-sized nanocrystals embedded in the amorphous matrix that may serve as nuclei for the t-phase during calcination. The calcined particles consist of 10–100 nm–sized t-crystals. For as-precipitated ZrO2 (R=60), week aggregates (50–100 nm) of largely amorphous 4–20 nm-sized particles after calcination yield a mixture of t-and monoclinic (m-) nanocrystals. PEELS fingerprints of the band structure with the intensity threshold matching the expected position of a direct bandgap at 4–5 eV allow to differentiate between the amorphous and nanocrystalline ZrO2. Stabilization of t-phase (R=5) with sizes up to 16 times larger than reported earlier is likely due to strain-induced confinement from surrounding growing grains, which suppress the volume expansion associated with the martensitic t-m transformation. For R=60, loose nanoparticle agglomerates cannot suppress the transformation. In this case, the t-phase may be partially stabilized due to a crystal size effect and /or to the presence of m-phase.

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