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The optical properties of TiO2 are changed while doped with impurity atoms. This paper made a systematical calculation of the bandgap, the density-of-states (DOS), the optical properties for pure TiO2, and Bi-doped anatase TiO2 according to the first-principles plane wave ultrasoft pseudopotential method which is primarily based on the density functional theory (DFT). The calculation results exhibit that the bandgap decreased after doping, and the impurity energy level is produced into the bandgap of Bi-doped TiO2, which makes red-shift for the absorption band edge of Bi-doped TiO2 and the absorption is enhanced more in the visible light range. [ABSTRACT FROM AUTHOR]

The optical properties of TiO2 are changed while doped with impurity atoms. This paper made a systematical calculation of the bandgap, the density-of-states (DOS), the optical properties for pure TiO2, and Bi-doped anatase TiO2 according to the first-principles plane wave ultrasoft pseudopotential method which is primarily based on the density functional theory (DFT). The calculation results exhibit that the bandgap decreased after doping, and the impurity energy level is produced into the bandgap of Bi-doped TiO2, which makes red-shift for the absorption band edge of Bi-doped TiO2 and the absorption is enhanced more in the visible light range. [ABSTRACT FROM AUTHOR]

Improving the thermal conductivity and anti-leakage behavior of phase change materials (PCMs) is beneficial for their applications in thermal storage and thermal management. In this study, a series of shape-stable composite PCMs (CPCMs) were prepared using a simple physical blending and vacuum impregnation method. Metal–organic frameworks (MOFs) synthesized by a hydrothermal method can effectively avoid the leakage of paraffin wax (PW), while the synergistic effect of expanded graphite (EG) and multi-walled carbon nanotubes (MWCNTs) strengthened the internal heat transfer of the CPCMs. The thermal conductivity of the CPCM (S5) containing 4 wt% EG and 1 wt% MWCNTs is 10.6 times higher than that of PW (2.23 vs. 0.21 W m−1 k−1). The sample S5 exhibits excellent latent heat (80.8 J g−1), resistance (3846 Ω), thermal cycling stability, and shape stability and superior thermal management performance. The feasible preparation strategy for PCMs provided here has enormous potential applications in electronic product thermal management and thermal energy harvesting. [ABSTRACT FROM AUTHOR]

Subspace clustering segments a collection of data from a union of several subspaces into clusters with each cluster corresponding to one subspace. The geometric information of the dataset reflects its intrinsic structure and can be utilized to assist the segmentation. In this paper, we propose side-information-induced reweighted sparse subspace clustering (SRSSC) for high-dimensional data clustering. In our method, the geometric information of the high-dimensional data points in a target space is utilized to induce subspace clustering as side-information. We solve the method by iterating the reweighted l1-norm minimization to obtain the self-representation coefficients of the data and segment the data using the spectral clustering framework. We compare the performance of our proposed algorithm with some state-of-the-art algorithms using synthetic data and three famous real datasets. Our proposed SRSSC algorithm is the simplest but the most effective. In the experiments, the results of these clustering algorithms verify the effectiveness of our proposed algorithm. [ABSTRACT FROM AUTHOR]