recently, the al2o3–tio2–zro2 system has found valuable applications, particularly, as a support for nox storage–reduction (nsr) catalysts. nanocomposite powders were prepared from the co-precipitation method in inorganic precursors. the behaviors of mixed oxide nanoparticles under ultrasonic irradiation, such as dispersion, and crushing were studied. phase transformations, crystallite size, an...

The calcination reaction of limestone (CaCO3) to yield lime (CaO) is at the heart of many industrial applications as well as natural processes. In the recently emerged calcium-looping technology, CO2 capture is accomplished by the carbonation of CaO in a gas-solid reactor (carbonator). CaO is derived by the calcination of limestone in a calciner reactor under necessarily high CO2 partial pressu...

Mike Meier University of California, Davis September 13, 2004 Figure 1. FEG-SEM image of nanosized aluminum oxide powder. Note the magnification and the size of the micron bar. Also note how the smaller particles and the edges of the larger particles appear to be somewhat transparent. This is because much of the 5 kV electron beam can pass through these thinner parts of the particles. CRYSTALLI...

A single and self-contained method for determining the crystallite-size distribution and shape from experimental x-ray line profile data is presented. We have shown that the crystallite-size distribution can be determined without assuming a functional form for the size distribution, determining instead the size distribution with the least assumptions by applying the Bayesian/MaxEnt method. The ...

We report Monte Carlo simulations of the melting of a singlepolymer crystallite. We find that, unlike most atomic and molecular crystals, such crystallites can be heated appreciably above their melting temperature before they transform to the disordered ”coil” state. The surface of the superheated crystallite is found to be disordered. The thickness of the disordered layer increases with superh...

We have investigated the crystallization of amorphous equiatomic NiTi thin films sandwiched between two protective silicon nitride barrier films using optical, atomic force, and transmission electron microscopy. Crystallite nucleation occurs homogeneously inside the NiTi films because small composition shifts at the interfaces between NiTi and surrounding layers suppress heterogeneous nucleatio...

A high-pressure silicon infiltration technique was applied to sinter diamond–SiC composites with different diamond crystal sizes. Composite samples were sintered at pressure 8 GPa and temperature 2170 K. The structure of composites was studied by evaluating x-ray diffraction peak profiles using Fourier coefficients of ab initio theoretical size and strain profiles. The composite samples have pr...

Present work aims to investigate effect of 100 MeV oxygen ion irradiation on the vibrational modes of zinc ferrite nanoparticles. Nanosize zinc ferrite systems of different crystallite size ranging from 12-62 nm were irradiated at the fluence of 1×10(13) and 5×10(13) ions/cm(2). High resolution transmission electron micrograph study indicates the structural disorder induced by ion irradiation. ...

A misalignment of anisotropic crystallites causes small values anisotropy and decreases the critical current density textured polycrystalline superconductors. To relate crystallite out-plane anisotropy, magnetic properties Bi2223 superconductor were investigated. distribution orientation angles was determined using different data: scanning electron microscopy images hysteresis magnetization loo...