It is well known that adding small amounts of Ti and B into aluminium casting alloys increase the fluidity, feedability, strength, fatigue resistance and pressure tightness. These occur because of Ti and B within the master alloys create heterogeneous nucleation sites by forming such intermetallic compounds as TiB 2 , Al 3 Ti and AlB 2. It is also known that the solidification time is influential on the formation of final grain size of aluminium cast parts. However the combining effects of both grain refining and solidification time has not been studied properly. Therefore, in this work, the effects of the grain refining and solidification time have been investigated on a sand-cast Al-4wt%Cu alloy. To determine solidification time effect, a tests mould having different section thickness has been used.

We report herein a glucose biosensor based on glucose oxidase (GOx) immobilized on ZnO nanorod array grown by hydrothermal decomposition. In a phosphate buffer solution with a pH value of 7.4, negatively charged GOx was immobilized on positively charged ZnO nanorods through electrostatic interaction. At an applied potential of +0.8V versus Ag∕AgCl reference electrode, ZnO nanorods based biosensor presented a high and reproducible sensitivity of 23.1μAcm−2mM−1 with a response time of less than 5s. The biosensor shows a linear range from 0.01to3.45mM and an experiment limit of detection of 0.01mM. An apparent Michaelis-Menten constant of 2.9mM shows a high affinity between glucose and GOx immobilized on ZnO nanorods.

Novel microelectrodes or microsensors may be based in future on the extraordinary single‐crystalline, channel‐structured β‐AgVO3 compound (see image) created by a simple hydrothermal process. The synthesis and electron transport in these compounds are discussed. It is shown that, depending on the electric field, the transport mechanism changes, which in turn influences the electronic behavior.

One-dimensional (1D) semiconductor metal oxide nanostructures, such as nanowires, nanobelts, and nanotubes, have attracted considerable attention due to their prominent electrical, optical, and chemical properties and potential applications in nanoscale electronic and optoelectronic devices. [1][2][3][4][5] However, the properties and applications of those nanomaterials are limited by their simple binary systems.[6] Therefore, synthesis of complex functional nanomaterials with controlled size and morphology, such as core/shell quantum dots, [7] nanowires and nanobelts, [8][9][10][11] heterostructures, [6,12] superlattices, [13] and nanotubes, [14][15][16] are highly desirable. Furthermore, 1Dternary nanocomposites, such as Zn 2 SnO 4 , [8][9][10]17] Zn 2 TiO 4 , [18] ZnGa 2 O 4 , [11,16] MgAl 2 O 4 , [14] CoFe 2 O 4 , [19] exhibit specific functions that are unattainable by common binary composites. Conventional synthesis methods of those ternary composites usually involve high-energy ball milling of two binary solid oxides [18] or a high-temperature solid reaction, [20,21] which are not suitable for 1D nanostructure growth. Only recently, syntheses of single-crystal ternary oxide nanowires and nanotubes have been achieved by using Ga 2 O 3 , MgO, or ZnO nanowires as template. [11,14,15] For face-centered cubic (fcc) nanostructures, twinning is probably the most common structural defect, especially in metal and metal alloy nanoparticles, [22,23] where two subcrystallites share a facet to form a mirror image of each other. Twinning is occasionally observed in binary systems, such as cubic ZnS and InP nanowires, [24,25] both of which have a preferential <111> growth direction. However, reports on the synthesis of twinned structures of fcc ternary nanowires are rare; [10] that is, the formation of twinned nanowires has yet to be revealed.Zinc titanate (Zn 2 TiO 4 ) is an inverse spinel, which has been used as a catalyst and pigment in industry. It is one of the leading regenerable catalysts and has been demonstrated to be a good sorbent for removing sulfur-related compounds at high temperature. [26,27] As a dielectric material, its physical, electrical, and optical properties have been studied for various applications. [21,28,29] In this Communication, we shall demonstrate a three-stage synthesis of twinned Zn 2 TiO 4 nanowires using ZnO nanowires as template, which could be further developed for controlled synthesis of ternary oxide nanostructures. Figure 1a-c shows the scanning electron microscopy (SEM) images of ZnO nanowires and ZnO/Ti core/shell nanowires before and after annealing, respectively. The as-grown ZnO nanowires shown in Figure 1a are randomly aligned, of about 40-60 nm in diameter, and 10 lm in length. It can be seen clearly that the morphology of the ZnO nanowires is reserved after coating with Ti (Fig. 1b). The surface is smooth and the diameter of the Ti-coated nanowires is increased to 70-100 nm. No aggregated Ti particles could be seen in Figure 1b, indicating a uniform deposition of Ti on ZnO ...

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