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Crystallographic characteristics of the β-Mg 17 Al 12 phase have been investigated in the pre-compressed and aged Mg-9.0 wt%Al-1.0 wt%Zn alloy. Due to pre-compression, morphologies of the β phases became much wider and shorter. The aspect ratio was reduced dramatically. Besides, octahedron shaped β phase with Crawley OR have been observed and portion of the β phase with Crawley OR increased. The twins generated by compression affect the ORs of the β phase. The OR between the β particle and the {1 0 −1 2} twin is: [1 −2 1 0] α //[1 1 −1] β , (0 0 0 2) α near parallel to (1 −2 −1) β . ORs between β particles and the {1 0 −1 1} twin were more complex. Two typical ORs between the β particles and the {1 0 −1 1} twin have been identified as: [1 −2 1 −3] T //[1 1 0] β1 , (1 −1 0 1) T //(3 −3 0) β1 and [1 −2 1 −3] T //[1 1 3] β2 , (0 −1 1 1) T //(2 1 −1) β2, which have rarely been reported before. [ABSTRACT FROM AUTHOR]

The pseudo-Hall effect in n-type single crystal 3C-SiC(1 0 0) with low carrier concentration has been investigated. Low pressure chemical vapor deposition was used to grow the single crystal n-type 3C-SiC(1 0 0) and Hall devices were fabricated by photolithography and dry etch processes. A large pseudo-Hall effect was observed in the grown thin films which showed a strong dependence on the crystallographic orientation. N-type 3C-SiC(1 0 0) with low carrier concentration shows a completely different behavior of pseudo-Hall measurements as compared to the p-type 3C-SiC(1 0 0). Contrary to p-type, the effect is maximum along [1 0 0] crystallographic orientation and minimum along [1 1 0] orientation. Moreover, the observed pseudo-Hall effect is 50 % larger than p-type with higher carrier concentration grown by the same process which makes n-type 3C-SiC(1 0 0) with low carrier concentration more suitable material for designing highly sensitive micro-mechanical sensors. [ABSTRACT FROM AUTHOR]

Cu 2 ZnSnS 4 (CZTS) films applicable to an absorber material in thin film solar cells were prepared at room temperature by pulsed DC magnetron sputtering from a CZTS ceramic target, and the effects of sputtering pressure on the phase, preferred orientation and composition of the deposited CZTS films were investigated. The results indicated that the dominant phase in the deposited films was Kesterite structure, only having the trace impurity phase of Cu 2− x S. The preferred orientation was gradually converted from (2 2 0) to (1 1 2) with increasing sputtering pressure. Moreover, the composition of the deposited films was also affected by the sputtering pressures. [ABSTRACT FROM AUTHOR]

The galvanic-cell-based synthesis is considered as an effective method for the seed-layer free preparation of ZnO nanorods. However, the nucleation stage of the growth which decides the final structures of ZnO nanorods is still not well-understood. Here we show that the nucleation is almost completed after two minutes of growth and the galvanic-cell-based method results in a condensed ZnO layer beneath of the ZnO nanorods. Beyond this finding, we propose a hybrid approach that combines the galvanic and hydrothermal growth to fabricate the condensed-layer free, well-separated ZnO nanorods that might be compatible for the ZnO-based devices. [ABSTRACT FROM AUTHOR]

Carbon fiber cloth/epoxy resin composites with different layer orientation angles were prepared to evaluate electromagnetic shielding properties in the X band. The results showed that the electrical conductivity, dielectric constant and shielding effectiveness of composites decreased with increase in layer angle. Absorbed power had the maximum value (0.577) at 49.60° with sample thickness 4.00 mm. After using carbonyl iron powder as the radio wave absorber, both conductivity and shielding effectiveness improved when layer angle was beyond 10.06°. Reflected power decreased while absorbed power increased with increase in layer angle and their variation rates decreased. Structure and function integrated shielding products made of these composites can be used to get the highest shielding effectiveness or highest absorbed power with designed layer angles. [ABSTRACT FROM AUTHOR]

Due to the crystal anisotropy, highly oriented films normally exhibit unique properties and performances. In this paper, Ag films were deposited using arc ion plating (AIP) at different substrate temperatures, substrate bias voltages and Ar pressures, and the relationship between the preferred orientation and deposition parameter of the films was investigated. The results exhibited that the preferred orientation of Ag films was influenced significantly by the deposition parameter due to the competition between the surface- and strain-energy minimization, and so both Ag films that exhibited highly preferred orientations of (1 1 1) and (2 0 0), respectively, were obtained at the optimum conditions. The relatively low friction was observed from the Ag film with highly preferred orientations of (1 1 1) because the (1 1 1) plane was the slip plane of face-centred cubic crystals. [ABSTRACT FROM AUTHOR]

Interaction of human osteoblast-like Saos-2 cells with a , b oriented silicalite-1 film is affected by its surface micro-roughness, controlled by a number of a oriented crystals on its surface, which can be simply tuned by synthesis conditions. The density of Saos-2 cells on days 1 and 3 after seeding increases with the number and dimensions of a oriented crystals. [ABSTRACT FROM AUTHOR]

Abstract: Oriented hydroxyapatite nanoclusters were achieved by reflux method in the presence of non-poisonous and well dissolved surfactant (potassium polyoxyethylene laurylether phosphate, MAEPK). Transmission electron microscopy (TEM) demonstrated uniform sizes of nanorods arranged in parallel to each other along the c-axis and formed partially oriented nanoclusters in the presence of MAEPK. The sizes of each nanoparticle were about 60–80nm in length and 20nm in width. MAEPK had an important impact on the morphology of product due to the structure of surfactant and a strong electrostatic interaction between ionized MAEPK and Ca2+ ions. The regulating formation mechanism of hydroxyapatite nanoclusters by MAEPK may extend the understanding of biomineralization process for the preparation of biomimetic materials. [Copyright &y& Elsevier]

Abstract: Cyclic microindentation experiments were performed using Vickers indenter to investigate whether microindentation induce phase transformations within amorphous silicon layer formed onto the machined surface after single point diamond turning. Although the microindentation induced phase transformation shows direct relationship with crystallographic direction during cyclic microindentation of silicon single crystal, the similar behavior was never probed into machined induced amorphization samples. Phase transformation was probed by micro Raman spectroscopy, which revealed direct evidence not only of recrystallization but also the multiple phase generation. The results indicated that the direction [100] presented as more susceptible to undergo phase transformation and achieve multiple phases with less microindentation cycles than the [110] one. [Copyright &y& Elsevier]

Abstract: A range of silica nanofibers with refined mesoporous microstructures were successfully synthesized via the combination of electrospinning and the sol–gel method. It was found that the concentration of nonionic surfactant Pluronic F127 (EO106PO70EO106) significantly influenced the morphology and mesoporous structure of silica nanofiber. With the reduced F127/Tetraethyl orthosilicate (TEOS) mass ratio, from 0.28 to 0.14, the diameter of silica nanofibers decreased from 453nm to 130nm, and more importantly, the size and the orientation of the internal mesopores were remarkably regulated. It has therefore been a critical step forward to a new hierarchical silica fiber for modern optical and biomedical applications. [Copyright &y& Elsevier]

Abstract: The TiO2 films were prepared on Pt/Ti/SiO2/Si substrate by a laser chemical vapor deposition method. With increasing laser power (P L) from 48 to 98W, the deposition temperature (T dep) monotonously increased from 849 to 929K. At T dep=849K (P L=48W), the rutile TiO2 film was prepared with strong (110) and (200) peaks. With increasing T dep from 849 to 883K (P L=71W), the intensity of (110) peak increased. The (110)-oriented TiO2 films were obtained for T dep beyond 903K (P L=81W). All TiO2 films showed faceted grains with the columnar cross-section. With increasing T dep, the grain size increased and the column became wider. The high deposition rate (R dep) ranged from 13.04 to 24.84μmh−1. [Copyright &y& Elsevier]

Abstract: CuO nanorods with thin diameter of about 5nm were prepared at 50°C with the assistance of polyethylene glycol (PEG) as growth directing agent, and these thin rods had a strong tendency to aggregate with parallel orientation. PEG was found to be effective for controlling the size of CuO, and the length of CuO nanorods was decreased by increasing the molecular weight of PEG. CuO nanoparticles with size ranging from 80 to 100nm were produced if polyethylene oxide (PEO) 400,000 was employed. The CuO samples were characterized by SEM, TEM, and XPS techniques. The band gap of CuO nanorods is estimated to be 2.30eV according to the UV–vis absorption spectrum, and such value is larger than that for bulk CuO probably due to the quantum confinement effect. [Copyright &y& Elsevier]

Abstract: Preferentially oriented thick and thin compacts of zeolite L with a large anisotropy in their crystal structures were successfully prepared by colloidal processes in a strong 12T magnetic field. The orientation along the direction of the applied magnetic field was characterized by XRD using slip-cast compacts. In the present experiments, it was revealed that the c-axis of zeolite L was an easy-magnetization axis. The c-axis oriented zeolite L layer with a thickness of ca. 3μm was formed on a porous ceramics substrate via electrophoretic deposition in a strong magnetic field applied perpendicular to the surface of the substrate. [Copyright &y& Elsevier]

Abstract: A series of lanthanum and calcium modified PbTiO3 [(Pb1−x−y La x Ca y )Ti1−x/4O3] thin films deposited on (111)Pt/Ti/SiO2/Si substrate were successfully achieved using a sol–gel route. It was found that all the (Pb1−x−y La x Ca y )Ti1−x/4O3 films exhibited high (100)-orientation, and the La and Ca contents played a significant role in their electric properties. The dielectric loss, fatigue and leakage current characteristics of films became worse with increasing Ca content, and the (Pb1−x−y La x Ca y )Ti1−x/4O3 film (x=0.1,y=0.1) possessed excellent piezoelectric and ferroelectric properties with maximum piezoelectric constant (d 33∼132pm/v) and maximum remanent polarization (Pr∼29μC/cm2). These results indicate that the highly oriented (Pb1−x−y La x Ca y )Ti1−x/4O3 film with appropriate content of La and Ca doped is a promising candidate for the mechatronics and MEMS applications. [Copyright &y& Elsevier]