In this article, hierarchical flower-like ZnO nanostructures with controlled morphology and dimensions have been synthesized by solution phase approach and functionalized by Au nanoparticles (AuNPs) with the combination of electrodeposition to explore novel applications. The photocatalytic activity and lithium storage capacity of these hybrid nanostructures have been investigated. It has been found that hybrid nanostructure combining the large specific surface area, stability and catalytic activity of small AuNPs, demonstrate the higher photocatalytic activity than that of pure ZnO. Furthermore, an initial discharge capacity of 1280 mA h g À1 and a reversible capacity over 392 mA h g À1 at the 50 cycles are achieved for the Au-ZnO hybrid nanostructure, which is found to be much better than that of any previously reported ZnO anodes. The improved lithium storage capacity and cycle life of the Au-ZnO electrode result from the Li activity of Au-ZnO phase. The photocatalytic and electrochemical activity of Au-ZnO hybrid nanostructures provide a new platform for energy storage, environmental remediation and photocatalysis applications.

Effects of Cu content and preaging treatments on precipitation sequence and artificial aging response in aluminum alloy 6022 were investigated using transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and hardness tests. It was found that Cu induces the formation of Q and its precursor metastable phases and has a beneficial effect on the kinetics of artificial aging. For the alloy with 0.07 wt pct Cu, the precipitation sequence is GP zones → needlelike ␤ Љ → rodlike ␤ Ј ϩ lathlike QЈ → ␤ ϩ Si. On the other hand, the precipitation sequence in the alloy with 0.91 wt pct Cu is GP zones → needlelike ␤ Љ → lathlike QЈ → Q ϩ Si. For the artificial aging condition of 20 minutes at 175 ЊC, which is the typical automotive paint bake condition, suitable preaging treatments were found to significantly reduce the detrimental effect of the natural aging on artificial aging response.

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Certain large DNA viruses, including those in the Marseilleviridae family, encode histones. Here we show that fused histone pairs Hβ-Hα and Hδ-Hγ from Marseillevirus are structurally analogous to the eukaryotic histone pairs H2B-H2A and H4-H3. These viral histones form "forced" heterodimers and a heterotetramer of four such heterodimers assembles DNA to form structures virtually identical to canonical eukaryotic nucleosomes.Many living organisms, particularly in the domain Eukarya, assemble DNA into chromatin to regulate the structure and accessibility of their genomes to nuclear machinery critical for cellular functions 1 . The nucleosome is the primary, repeating unit of chromatin, and comprises an octamer of histone proteins wrapped by ~147 bp of DNA 2,3 . The four histone proteins, H2A, H2B, H3, and H4, harbor a conserved histone-fold (HF) dimerization motif. Canonical histones in Eukarya form obligate heterodimers in which H2A dimerizes exclusively with H2B and H3 with H4. Similarily, in Archaea, homodimers of HF-containing proteins can assemble higher-order structures with DNA 4,5 .

The microstructural evolution during age hardening of a Cu-bearing Al-Mg-Si alloy has been investigated by the three-dimensional atom probe (3DAP) and transmission electron microscope (TEM) techniques, in order to clarify the effect of Cu on the initial age-hardening response. After 30 minutes of artificial aging at 175 ЊC, the alloy shows a significant increase in hardness. The TEM observations have revealed that very fine, needle-shaped ␤ Љ precipitates are formed in addition to spherical GuinierPreston (GP) zones, whereas only the spherical GP zones are observed in the Al-Mg-Si ternary alloy using the same aging condition. The number density of the precipitates is significantly affected by the preaging conditions. The 3DAP analysis shows that the distribution of Cu atoms is uniform after 30 minutes of artificial aging at 175 ЊC, whereas Cu atoms are incorporated into the needle-shaped ␤ Љ precipitates after 10 hours of aging at 175 ЊC. Based on these microanalytical results, the effect of Cu additions on the age-hardening response of Al-Mg-Si alloys is discussed.

Tantalum oxide films were deposited on silicon substrates at a temperature of ∼450°C by heating a pure tantalum foil in a rough vacuum. The films were amorphous in structure and consisted of fully oxidized Ta2O5 and (TaOx, x<2.5) suboxides. This feature resulted in strong visible light emission from the films further oxidized in the air at temperatures of 200–300°C. The mechanism for this photoluminescence behavior of the amorphous tantalum oxide films was also investigated and discussed. This study suggests that wide-band-gap materials could act as effective visible light emitters and provides a simple route to synthesize such materials.

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