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F doping BiFeO3-xFx (x=0, 0.02, 0.04, 0.06, 0.08) thin films were successfully fabricated on ITO/glass substrates by sol-gel method. X-ray diffraction analysis indicated that the un-doped BiFeO3 and F doping BiFeO3 thin films presented rhombohedral structure with the space group R3c. F-doping is found to significantly enhance the dielectric constant and decrease the leakage current density for x=0.08 compared with x=0. This study provides direct evidence that the multiferroic characteristics of BiFeO3 are sensitive to the anion doping, such as F, providing a convenient alternative to manipulate the electric polarization in multiferroic oxides.

The roadbed base of railway in Qarhan Salt Lake area entirely consists of brine saturated rock salt formations. However, low salinity brine would cause corrosion for roadbed and the stability of rock salt roadbed would be directly affected. In this paper, physical and mechanical properties of brine-dissolved rock salt have been tudied, as well as Computer Tomography was used to scan and analyze the meso-structural changes in rock salt before and after corrosion. The results show that density of rock salt would be changed obviously in the process of corrosion.The deriving or closing of meso-fissures in rock salt could been found with rock salt immigrating and corrosion damage.

We developed a SMEDDS to enhance the oral delivery of resveratrol by using high performance liquid chromatography, a pseudo ternary phase diagram and a central composite design (CCD). We found that the optimal formulation of 12.69% greoil gtcc, 62.29% Cremophor EL, and 25.02% Labrasol. We characterized the particle size and zeta potential of the final SMEDDS.

For considering the magnetic fields produced by the UHVDC transmission in our country which may have influence on human and communication equipment. This paper use ANSYS finite element software to modeling to analysis the regularity of distribution and order of magnitude of the magnetic fields produced by the UHVDC transmission. By comparing with the limitation of the correspond criteria. We can infer that the electromagnetic fields produced by the UHVDC transmission whether have influence on our environment and harmful to human.

S, Sr-codoped TiO2 were prepared by sol-gel mothod, using titanium (IV) n-butoxide, strontium nitrate and thiourea as precursors. And the samples were characterized by X-ray diffraction (XRD), Fourier infrared spectroscopy (FTIR), scanning electron microscopy (SEM). The results showed that the S, Sr-codoped TiO2 were single-phase anatase structure, and the particle growth and crystal phase transformation can be restrained by doping. The photocatalytic activity and reusability of the catalysts under UV light (365nm) was investigated with methyl orange as the model compound. The results showed that S, Sr-codoped TiO2 had the highest photocatalytic activity among all as-prepared samples. The kinetic study showed that this photocatalytic process coincided with the Langmuir-Hinshelwood (L-H) pseudo first order reaction model.

The microstructure, hardness and corrosion resistance of AZ91D alloy were investigated under different solution treatments and artificial aging conditions.When ascast AZ91D alloy was heat treated at 415°C by solution treatmentfor 12 h and artificially aged at 200°C, the volume fraction of precipitates increased with the aging time up to 10 h.When ascast AZ91D alloy was treated at 430°C by solution treatment for 12 h and artificially aged at 200°C for 10h, the volume fraction of precipitates reached a peak value.The results of the corrosion test showed that a high corrosion resisting of the second phase precipitates was beneficial to improving the strength and hardness. Solution treatment at 445°C temperature for 12 h destroied the consecutiveness of β-Mg17Al12 phases.

The current paper deals with the fractal effective thermal conductivity model for fibrous porous media containing unsaturated water moisture. The model is based on the thermal-electrical analogy and statistical self-similarity of porous media. The fractal effective thermal conductivity model can be expressed as a function of the pore structure (fractal dimension) and architectural parameters of porous media. It is expected that the model will be helpful in the evaluation of thermal comfort for textiles in the whole range of porosity.

The paper consider heat and moisture transport within cotton fabric exposed to fire as drying process. A mathematical model of simultaneous heat and moisture transfer is proposed for the prediction of temperature distributions during high heat flux condition based on the theory of drying. Shrinkage occurring in the drying zone was incorporated into the present numerical model. Using the model, we will can understand the drying mechanism and process of flame retardant cotton fabric used for thermal protective clothing. The discrete calculation and experiments will be presented in the further study.

With the background of global warming and energy crisis, the low carbon economy and low carbon city gradually call people’s attention. The core of low-carbon city and economy is to reduce carbon emissions and energy consumption. A low-carbon city relies on its low-carbon city planning. This article analyzes the connotation of low-carbon city and puts forward the notion of using low-carbon ideas in planning industrial structure, road transport planning and layout of the city to construct a better city.

The main factors of impacting Cone-Beam Computed Tomography (CBCT) image quality and their causes were studied, and an integrated method of enhancing CBCT image quality was proposed according to the Digital Radiography (DR) imaging model. First, the original polychromatic X-ray was filtered into quasi-monochromatic X-ray by the filter plate of copper-tungsten alloy, in order to improve the quality of the original projection images. Then, the integrated artifact corrections for projection images were processed on the order of dark field correction, gain non-uniformity correction, scatter correction and beam hardening correction, to avoid the one-sidedness of only correcting a certain kind of artifact. Experimental results show that the method can almost eliminate the main artifacts of CBCT system and improve image clarity and signal to noise ratio.