Synthesis of V5+‐doped Ag/AgCl photocatalysts with enhanced visible light photocatalytic activity

V⁵⁺‐doped Ag/AgCl photocatalysts were prepared via the ion exchange method. The catalysts were characterized using X‐ray diffractometry, transmission electron microscopy, and energy‐dispersive X‐ray, X‐ray photoelectron, Fourier transform infrared and ultraviolet–visible spectroscopies. The V⁵⁺‐doped Ag/AgCl photocatalysts show much higher photocatalytic activities than Ag/AgCl under visible light irradiation for methyl orange (MO) decomposition. Especially, the 2.0 wt% V⁵⁺‐doped Ag/AgCl photocatalyst shows the highest photocatalytic activity and also high stability after five cycles. The MO degradation rate during each cycle is almost maintained at 97%. Electron spin resonance spectroscopy and radical trapping experiments reveal that holes play an important role in the photocatalytic process.     

熔盐堆空气换热器结构完整性分析

熔盐堆作为第四代核反应堆备选堆型之一,运行温度高,对材料高温性能要求严格;熔盐堆空气换热器作为实验堆关键设备,工作温度高,启停机次数多,长期运行后,材料许用应力松弛下降,应力、应变可能超出允许限值,或发生蠕变疲劳失效。使用Workbench软件,对熔盐堆空气换热器进行力学分析,并对A级使用载荷要求进行结构完整性评定,结果表明:熔盐堆空气换热器满足力学性能要求,其中疲劳损伤占比重较大,高温蠕变损伤也较为显著。     

Split least‐squares finite element methods for non‐Fickian flow in porous media

In this article, we introduce two least‐squares finite element procedures for parabolic integro‐differential equations arising in the modeling of non‐Fickian flow in porous media. By selecting the least‐squares functional properly the presented procedure can be split into two independent subprocedures, one subprocedure is for the primitive unknown and the other is for the flux. The optimal order convergence analysis is established. Numerical examples are given to show the efficiency of the introduced schemes. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013     

Polymer and azo-dye composite: a photo-alignment layer for liquid crystals

In this article, we disclose a method to fabricate polymer-stabilised azo-dye photo alignment layers for liquid crystal. The idea includes the introduction of polymer network in the alignment layer, in optimal concentration, followed by two-step irradiation. The stabilised photo-alignment layer has been explored for different aspects of the display-related parameters, viz. anchoring energy, stability for various display-related environments as a function of concentration of monomer and irradiation, residual DC and voltage holding ratio. The composite photo-alignment layer offers well-suited parameters for the liquid crystal alignment and therefore could find application in a variety of modern photonic and display devices.     

Preparation of Fluorine-Containing Polyacrylate Emulsion by a UV-initiated Polymerization

A fluorine-containing polyacrylate emulsion was synthesized by a UV-initiated emulsion polymerization from methyl methacrylate (MMA) and hexafluorobutly methacrylate (HFMA) in the presence of 2-hydroxy-4-(2-hydroxyethoxy)-2-methyl-propiophenone (Irgacure 2959) as a hydrophilic photoinitiator at room temperature. The latex and films were characterized by Fourier transformed infrared (FT-IR) spectrometry, nuclear magnetic resonance (¹H-NMR, ¹⁹F-NMR) spectrometry, transmission electron microscopy (TEM), recycling gel permeation chromatography (GPC), dynamic light scattering (DLS), and contact angle (CA) analysis, respectively. The effects of photoinitiator and emulsifier concentration on the polymerization were discussed. Compared to the corresponding thermal polymerization, UV-initiated polymerization of the MMA/HFMA emulsion could be accomplished at a much higher speed. The polymerization conversion in UV-initiated polymerization reached 95% within 10 min at an emulsifier concentration of 0.6 wt%, photoinitiator concentration of 0.4 wt%, and monomer concentration of 10 wt%.     

四川省人口文化素质空间分布特征分析

本文以第五次、六次人口普查数据为基础,将人均受教育年限作为切入点,在GIS软件支持下,采用标准差、变异系数、空间自相关分析法等,从地理学视角系统地分析了四川省人口文化素质的空间分布特征,得出3点结论,最后,有针对性地提出了相关建议。     

Zero singularities in a ring network with two delays

In this paper, we consider a neural network model consisting of three neurons with delayed self- and nearest-neighbor connections. We provide multiple bifurcations of the zero solution of the system near zero eigenvalue singularity. Taking the coupling coefficients as the bifurcation parameters, four kinds of zero singularities are demonstrated through center manifold reduction and normal form calculation.     

A new method for preparing TiO2 catalyst honeycombs without sintering

Composite catalyst honeycombs without sintering were prepared via kneading, mulling, extrusion molding, and solidifying at room temperature with the magnesite oxychloride gels modified by nano-rice husk ash (RHA) as a solidifying agent. The effects of nano-RHA and composite water-resistant agents on the water resistance of magnesite materials were studied. The solidification of the modified magnesite gels on TiO₂ catalyst honeycombs was analyzed. The experiments show that the proportional addition of nano-RHA markedly increases the water resistance of magnesite materials without reducing the bending strength, and the softening coefficient increases from 0.29 to 0.78. With further addiition of the complex water-resistant agents, the softening coefficient increases from 0.78 to 0.97. The optimal mass ratio of MgO in the solidifying agent to TiO₂ is 4:1, and the bending strength of unsintered catalyst honeycombs is 11.46 MPa. The desulfurization rate and denitration rate of this composite catalyst honeycomb on simulation smoke was 97 and 65 %, respectively, in 3 h.