An inverse random source problem in a stochastic fractional diffusion equation

In this work the authors consider an inverse source problem the stochastic fractional diffusion equation. The interested inverse problem is to reconstruct the unknown spatial functions f and g (the latter up to the sign) in the source by the statistics of the final time data u(x, T). Some direct problem results are proved at first, such as the existence, uniqueness, representation and regularity of the solution. Then a reconstruction scheme for f and g up to the sign is given. To tackle the ill-posedness, Tikhonov regularization is adopted and some numerical results are displayed.Peer reviewe

Visible-Light Active and Magnetically Recyclable Nanocomposites for the Degradation of Organic Dye

Recyclable visible-light photocatalyst Fe3O4@TiO2 with core-shell structure was prepared by a simple synthetic strategy using solvothermal crystallization of titanium precursor on preformed Fe3O4 nanopartiles. The photo-degradation reaction of neutral red aqueous solution was tested to evaluate the visible-light photocatalytic activity of the as prepared Fe3O4@TiO2 nanoparticles, which show excellent photocatalytic activity compared with commercial P25 catalyst. Moreover, the Fe3O4@TiO2 nanocomposites can be easily separated from the reaction mixture, and maintain favorable photocatalytic activity after five cycles. The high visible light absorption of the Fe3O4@TiO2 nanocomposites may originate from the absence of electronic heterojunction, excellently dispersity and the high specific surface area of the as-synthesized Fe3O4@TiO2 samples

Visible-Light Active and Magnetically Recyclable Nanocomposites for the Degradation of Organic Dye

Recyclable visible-light photocatalyst Fe3O4@TiO2 with core-shell structure was prepared by a simple synthetic strategy using solvothermal crystallization of titanium precursor on preformed Fe3O4 nanopartiles. The photo-degradation reaction of neutral red aqueous solution was tested to evaluate the visible-light photocatalytic activity of the as prepared Fe3O4@TiO2 nanoparticles, which show excellent photocatalytic activity compared with commercial P25 catalyst. Moreover, the Fe3O4@TiO2 nanocomposites can be easily separated from the reaction mixture, and maintain favorable photocatalytic activity after five cycles. The high visible light absorption of the Fe3O4@TiO2 nanocomposites may originate from the absence of electronic heterojunction, excellently dispersity and the high specific surface area of the as-synthesized Fe3O4@TiO2 samples

Facile Synthesis of CeO2-LaFeO3 Perovskite Composite and Its Application for 4-(Methylnitrosamino)-1-(3-Pyridyl)-1-Butanone (NNK) Degradation

A facile and environmentally friendly surface-ion adsorption method using CeCO3OH@C as template was demonstrated to synthesize CeO2-LaFeO3 perovskite composite material. The obtained composite was characterized by X-ray diffraction (XRD), fourier transform infrared spectra (FT-IR), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), thermo-gravimetric analysis and differential scanning calorimetry (TG-DSC), N2 adsorption/desorption isotherms and X-ray photoelectron spectra (XPS) measurements. The catalytic degradation of nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) was tested to evaluate catalytic activity of the CeO2-LaFeO3 composite. Much better activity was observed for the CeO2-LaFeO3 composite comparing with CeO2 and LaFeO3. These results suggested that perovskite composite materials are a promising candidate for the degradation of tobacco-specific nitrosamines (TSNAs)

Doping Zn²⁺ in CuS Nanoflowers into Chemically Homogeneous Zn_0.49Cu_0.50S_1.01 Superlattice Crystal Structure as High-Efficiency <i>n</i>‑Type Photoelectric Semiconductors

Doping Zn²⁺ in CuS nanoflower into chemically homogeneous superlattice crystal structure is proposed to convert <i>p</i>-type CuS semiconductor to an <i>n</i>-type CuS semiconductor for significantly enhanced photoelectric response performance. In this study, the chemically homogeneous Zn-doped CuS nanoflowers (Zn_0.06Cu_0.94S, Zn_0.26Cu_0.73S_1.01, Zn_0.36Cu_0.62S_1.02, Zn_0.49Cu_0.50S_1.01, Zn_0.58Cu_0.40S_1.02) are synthesized by reacting appropriate amounts of CuCl and Zn­(Ac)₂·2H₂O with sulfur powders in ethanol solvothermal process. By tuning the Zn/Cu atomic ratios to ∼1:1, the chemically homogeneous Zn-doped CuS nanoflowers could be converted to the perfect Zn_0.49Cu_0.50S_1.01 superlattice structure, corresponding to the periodic Cu–S–Zn atom arrangements in the entire crystal lattice, which can induce an effective built-in electric field with <i>n</i>-type semiconductor characteristics to significantly improve the photoelectric response performance, such as the lifetime of photogenerated charge carriers up to 6 × 10^–8–6 × 10^–4 s with the transient photovoltage (TPV) response intensity to ∼44 mV. This study reveals that the Zn²⁺ doping in CuS nanoflowers is a key factor in determining the superlattice structure, semiconductor type, and the dynamic behaviors of charge carriers