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The relative contact angle (θRCA) for seven iron ore fines was measured by using Washburn Osmotic Pressure method under laboratory conditions. By choosing cyclohexane as the reference that can perfectly wet iron ore particles, the relative contact angles were measured and varied from 57° to 73°. With the volume % of goethite (φG) as the variable, a new model for relative contact angle was developed. The expected relative contact angle for pure goethite is about 56°, while that for goethite free samples is about 77°. Physical properties, such as surface morphology (SMI) and pore volume (Vpore) can influence the relative contact angle. The φG can be expressed as a function of SMI and VPore. Thus, we inferred that the relative contact angle is a function of φG for the iron ores used. The measured relative contact angles were found to be in good agreement (Radj 2 >0.97) with the calculated ones based on the research from Iveson, et al. (2004). Comparing with the model developed by Iveson et al.(2004), the new model for contact angle proposed in this paper is similar, but more detailed with two meaningful physical parameters. The modification of physicochemical properties on iron ores would be another topic in the further study on granulation.

A kind of embedded acoustic emission (AE) sensor for the concrete health monitoring was fabricated by using the 1-3 polymer/cement-based piezoelectric composite. The frequency bandwidth, sensitivity, threshold value, and response of the sensor were investigated. The results show that the embedded acoustic emission sensor has broad frequency bandwidth and low threshold value, and is very sensitive to crack propagation of the cement mortar in the loading test. Moreover, there is a good relationship between AE signals and the damage process of the cement mortar. The embedded acoustic emission sensor can be used to detect and collect the AE signals in different fracture stages, and make accurate judgments on the damage condition of the cement mortar. So, the embedded acoustic emission sensor is suitable for the concrete health monitoring. [ABSTRACT FROM AUTHOR]

Abstract: The accumulation of radiation-induced defect clusters and He bubble formation in He+ ion irradiated nanocrystalline TiO2 and Fe–TiO2 multilayer thin films were investigated using transmission electron microscopy (TEM). Prior to ion irradiation it was found that the crystallinity of TiO2 layers depends on the individual layer thickness: While all TiO2 layers are amorphous at 5nm individual layer thickness, at 100nm they are crystalline with a rutile polymorph. After He+ irradiation up to ∼6dpa at room temperature, amorphization of TiO2 layers was not observed in both nanocrystalline TiO2 single layers and Fe–TiO2 multilayers. The suppression of radiation-induced amorphization in TiO2 is interpreted in terms of a high density of defect sinks in these nano-composites in the form of Fe–TiO2 interphase boundaries and columnar grains within each layer with nano-scale intercolumnar porosity. In addition, a high concentration of He is believed to be trapped at these interfaces in the form of sub-nanometer-scale clusters retarding the formation of relatively larger He bubbles that can be resolved in TEM. [Copyright &y& Elsevier]

Abstract: Boron carbide thin films were deposited on silicon substrates using ion beam sputtering at different substrate temperatures. The chemical composition and the microstructure of the films were analyzed by X-ray photoelectron spectroscopy, and transmission electron microscopy, respectively. Although all films are amorphous despite their deposition temperature, their radial distribution functions derived from the transmission electron diffraction pattern disclose differences in the short-range order for films deposited below and above 350 °C. The nanoindentation hardness of the films was measured using a nanoindentor. The internal stress of the films was evaluated using a profiler based on Stoney''s equation. The experimental results suggest that the different hardness of the films is determined by the microstructure, rather than external factors. [Copyright &y& Elsevier]

Presents a study which investigated mixed convection from a cylinder embedded in a saturated porous medium. Formulation and numerical method; Results and discussion; Conclusions.

Abstract: Mn-doped ZnO nanorods with ∼30nm in diameter and ∼200nm in length were synthesized by a seed-mediated solution method. The structures, magnetic properties, as well as the annealing effect were characterized by transmission electron microscopy, electron energy loss spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectrum and physical properties measurement system. Magnetic properties measurement revealed that the Zn0.97Mn0.03O nanorods exhibited ferromagnetism with a saturation magnetization of 0.005emug−1 and a coercivity of 110Oe at 305K. After annealing the samples at 900°C for 2h in air, the nanorods were transformed into nanoparticle aggregates. The coercivity and saturation magnetization increased obviously. Detailed analyses proved that a phase-separation process was happened at the high temperature. In this process, most of the particles preserved the wurtzite ZnO structure, while a few small ones evolved into spinel-structured particles. The increasing of the ferromagnetism of the annealed sample is attributed to the formation of secondary phase Zn x Mn3−x O4. [Copyright &y& Elsevier]

Abstract: FePt/B4C multilayer composite films were prepared by magnetron sputtering and subsequent annealing in vacuum. By changing Fe layer thickness of [Fe/Pt]6/B4C films, optimal magnetic property (8.8kOe and remanence squareness is about 1.0) is got in [Fe(5.25nm)/Pt(3.75nm)]6/B4C sample whose composition is Fe rich and near stoichiometric ratio. The characterizations of microstructure demonstrate that the diffusion of B and C atoms into FePt layer depends strongly on B4C interlayer thickness. When B4C interlayer thickness of [Fe(2.625nm)/Pt(3.75nm)/Fe(2.625nm)/B4C]6 films is bigger than 3nm, stable value of grain size (6–6.5nm), coercivity (6–7kOe) and hardness (16–20GPa) is observed. Finally, the multifunctional single FePt/B4C composite film may find its way to substitute traditional three-layer structure commonly used in present data storage technology. [Copyright &y& Elsevier]