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The monoclinic LiMn0.9Cr0.1O2 irreversibly transforms to spinel-like structure m-LiMnO2 during the electrochemical cycling. Experimental results indicated that the (440) interplanar distance of LixMn2O4 at the charged state increases as the cycle number increases, while the (440) interplanar distance of LixMn2O4 at the discharged state decreases as the cycle number increases.A model for the transformation of monoclinic LiMn0.9Cr0.1O2 to the spinel LiMn2O4 is suggested. According to the suggested model, there may exist two types of s-LixMn2O4 when m-LiMnO2 transforms into s-LixMn2O4. The two types of spinel LixMn2O4 develop the nanodomain.

A series of Mn-doped LiNi0.85−xCo0.15MnxO2 compounds (x= 0, 0.1, 0.2 and 0.4) were prepared by the co-precipitation method. The effect and mechanism of Mn–doping on the microstructures and crystallite sizes of LiNi0.85−xCo0.15MnxO2 cathode materials were studied. The non-equivalent substitution of Mn ions for Ni ions induces a decrease in the average valence of nickel ions. The Mn-doping promotes the formation of the single phase compounds with more ordered structure.

Single-crystalline Si−CdSe biaxial p−n heterostructure nanowires (NWs) have been grown via chemical vapor deposition method and characterized. The Si and CdSe subnanowires have diameters of about 30 and 60 nm, respectively, and grow along the 1 and 0001 directions, respectively. Room-temperature photoluminescence (PL), Raman-scattering, and electrical transport measurements were made on single Si−CdSe biaxial heterostructure NWs. Strong CdSe band-edge emission peaked around 710 nm together with a broad emission centered at 600 nm is observed in the PL spectra. Intense sharp longitudinal optical phonon modes from both CdSe and Si are observed in Raman-scattering spectra. The resistivities, carrier concentrations, and carrier mobilities of single CdSe NW and Si subnanowire are estimated. A good rectification characteristic is observed in theI−Vcurve of Si−CdSe biaxial NW, which confirms that the Si−CdSe biaxial NW is a p−n heterostructure.

Corrosion behavior of aluminum based composites containing in‐situ TiB2, Al2O3and Al3Ti reinforcements in aerated 3.5% sodium chloride solution was investigated. The composites were prepared from the Al‐TiO2‐B system via reactive hot pressing. Polarization measurements showed that the composite containing high Al3Ti content (CA) exhibits higher corrosion current density than the composite containing a trace amount of Al3Ti phase (CB). Microstructural examination revealed that the pits were initiated at fractured Al3Ti blocks.

Wide-angle X-ray diffraction (WAXD) was used to investigate the effects of shear on the crystallization behavior of polypropylene (PP) with β-nucleating agent. The melt was subjected to shear at the shear rate from 0.5 to 60 s^-1 for 5 s with a CSS450 shear stage. For the PP with low content of the additive, the formation mechanism of the β crystals is almost the same as that of pure isotactic polypropylene (iPP), viz., shear induces. Otherwise, for the samples with high content of the additive, the formation mechanism of the β form are nucleating agent induces. The results clearly show that shear restrains the formation of high β phase for the melt with additive.