Microstructure Morphologies of Asphalt Binders using Atomic Force Microscopy

We investigated microstructure morphologies of three asphalts（SK, Karamay, and Esso） used in China using atomic force microscopy（AFM）. The topography and phase contrast images were obtained. Topographic profile and three dimensional images were described. Roughnesses of microstructure were calculated. And the chemical compositions of asphalt were tested to explain the microstructural mechanism of the asphalt. The results show that the topography and phase image in atomic force microscopy are appropriate to evaluate the microstructure of the asphalt binder. There are significant differences in microstructural morphologies including bee-like structure, topographic profile, 3D image, and roughness for three asphalts in this study. There are three different phases in microstructure of asphalt binder. The oil source and chemical composition of asphalt, especially asphaltenes content have a great influence on the microstructure.

Synthesis of Sodium Beta Alumina Films by Heat Treatment of Sodium Aluminum Oxides

Sodium beta alumina（Na-β-alumina） films were synthesized by heat treatment of NaAl6O（9.5）and γ-NaA1O2 films at temperatures of 1 373-1 573 K.Single-phase γ-NaA1O2 and NaAl6O（9.5） films were prepared by laser chemical vapor deposition at the deposition temperatures of 976 and 1 100 K,respectively.Subsequent heat treatment of the films resulted in the formation of Na-β-alumina with α-Al2O3 at temperatures above 1 373 K for NaAl6O（9.5） and 1 473 K for γ-NaA1O2.On heat treatment at temperatures of 1 473-1 573 K,the faceted morphology with terraces of the as-deposited（110）-oriented γ-NaAlO2 films transformed to a porous morphology with platelet grains comprising Na-β-alumina and α-Al2O3.On heat treatment at temperatures of1 373-1 473 K,the pyramidal,faceted grains of as-deposited NaAl6O（9.5） films transformed to planer,shapeanisotropic morphology in the film of mixed Na-β-alumina and α-Al2O3.A dense morphology was observed in both the as-deposited and heat-treated NaAl6O（9.5） films.

Magnetic and electrochemical behavior of rhombohedral α-Fe_2O_3 nanoparticles with (104) dominant facets

Uniform rhombohedral α-Fe2O3 nanoparticles, -60nm in size, were synthesized via a triphenyl- phosphine-assisted hydrothermal method. Scanning electron micrograph （SEM） and transmission electron micrograph （TEM） analyses showed that the as-synthesized rhombohedral nanoparticles were enclosed by six （1 04） planes. The concentration of triphenylphosphine played an important role in morphological evolution of the α-Fe2O3 nanoparticles. The as-prepared rhombohedral nanoparticles possessed remanent magnetization Mr of 2.6 × 10^-3 emu/g and coercivity Hc of 2.05 Oe, both lower than those of other α-Fe2O3 particles with similar size, indicating their potential applications as superparamagnetic precursor materials. Furthermore, these rbombohedral α-Fe2O3 nanoparticles exhibited good sensor capability toward H2O2 with a linear response in the concentration range of 2-20 mM.

Influence of morphology on basicity of CeO2 and its use in 2-chloroethyl ethyl sulfide degradation

Three CeO_2 samples with different morphologies, i.e., cubes, rods, and spindles, were synthesized and investigated for 2-chloroethyl ethyl sulfide（2-CEES） degradation. The samples were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, the Brunauer-Emmett-Teller method, and temperature-programmed CO_2 desorption. It was found that morphologies of CeO_2 could strongly affect the surface properties and the 2-CEES degradation activities. The surface basicity and the continuous 2-CEES degradation activity of spindle-like CeO_2 were much better than those of the other CeO_2 samples, although all the samples had identical chemical compositions. That was benefited by the largest surface area, abundant microcracks, and surface oxygen vacancies of the spindle-like CeO_2.