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ABSTRACT The present study aims to characterize the creep behaviour of Polystyrene Aggregate Concrete (PAC). The creep and creep recovery of PAC were determined experimentally and compared with normal weight [...]

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.

More than twenty years were needed for people to understand the formation mechanism of the periodic-layered structures not only because of the complications of pattern formation, but also due to the limits of traditional diffusion theories. Based on the general theory of interdiffusion growth proposed by Y.C. Chen et al. [1], the quantitative model of periodic layer formation during solid state reactions has been succeeded [2]. The experimental results shown in this paper proved one of the model’s predicts that the reactive diffusion system Zn/Fe3Si with clamp press annealed at 663K should be mixed controlled. Also, the important influence of the uniaxial compressive stress on the diffusion coefficient was emphasized and the reasons are discussed.