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The stability of SiC and SiO2 in helium with little water vapor is studied in this paper in order to confirm whether they can service as anti-oxidation layers on the surface of fuel elements of high temperature gas-cooled reactor (HTR) under water-ingress accident. Through thermodynamic analysis, it is found that the influence factor controlling the critical temperature of passive oxidation for SiC in He-H2O is the partial pressure of H2O; the critical temperature of passive oxidation for SiC increases with the partial pressure of H2O. The influence factors controlling the critical temperature of decomposition for SiO2 are the partial pressure of H2O and the amount of H2O in gas for 1 mol SiO2, the critical temperature of decomposition for SiO2 increases with the partial pressure of H2O while it decreases with the amount of H2O in gas for 1 mol SiO2. SiO2/SiC composite coating is more suitable than SiC coating in He-H2O with little H2O.

The weight loss rate, FTIR characteristic, static mechanical properties and dynamic mechanical properties of neat epoxy resin and glass fiber/ epoxy resin laminates (GF/EP) after thermal-cold cycling were studied in this paper. The rule of static tensile and flexural strength of neat epoxy resin and GF/EP after ageing was investigated through the static mechanical properties analysis. The ageing mechanism of GF/EP was studied by analyzing the storage modulus (E′), loss modulus (E"), loss factor of GF/EP and FITR of epoxy resin. The results show that the weight loss rate increases with the ageing time，which is up to 9% after 400 times ageing cycle. The strength and flexural strength of GF/EP decreased by 6% and 21% after ageing, while the tensile strength of neat epoxy resin increases by 8% and its flexural strength increases slightly after ageing. The mechanism analysis reveals that internal defects of GF/EP would be induced by thermal-cold cycling stress, which results in the interface bonding strength dropping and the performance reducing.

Two kinds of hypercrosslinked resin ZH-01 and ZH-03 were prepared in this study. Experimental investigations were conducted to study the adsorption characteristics of 4-chlorophenol on the hypercrosslinked resins by method of static adsorption. The equilibrium adsorption data was fitted to Freundlich adsorption isotherm model to evaluate the related parameters. The results showed that the changes of enthalpy, free energy, entropy indicate an exothermic, spontaneous and disorder decreasing process happened in the adsorption. It was also shown that, respecting to the adsorption capacity, the adsorbents prepared here are better than the Amberlite XAD-4 for removing the 4-chlorophenol in aqueous solutions.

In order to overcvome the shortage of current dust control technology in coal mine, especially the traditional water spray method, a two-phase foam materials preparation experimental system was established based on the simulation of water and air conditions in underground coal mine. And a new technique which can prepare high-performance foam was proposed, and the main technical parameters and application conditions to implement foam dedusting were determined through plenty of experimental. Then, the new technique had been applied in two large underground coal mine. The results show that its dedusting efficiency to total dust and respirable dust reached 90.5% and 85.4% in the fully-mechanized excavated face, as 1.97 times and 1.88 times higher than water spray respectively. However, its water consumption is only as 10% to 20% as conventional water spray. It is proved that this new technique for preparation of foam can reduce mine dust concentration remarkably and improved the working environment obviously, and has a broad application prospect and promotion value to control dust in underground coal mines and other related industry.

Benvitimod (3,5-dihydroxy-4-i-propylstilbene) is a novel drug developed for common skin disorders such as atopic dermatitis by Welichem Biotech Inc. in Canada and Celestial Pharmaceuticals (Shenzhen) Co. Ltd. in China. But the ideal synthesis method is not reported so far. Herein an efficient synthesis method which is operated under the mild conditions is reported. According this route, the total yield will reach 40.3 - 48.1% and the benefits of the improved method are easily operating and environment friendly.

Carbon-doped LiFePO4/C cathode materials for lithium power batteries were prepared by liquid-state precipitation reaction. Their properties were studied by using XRD, SEM, elemental analysis, FTIR and A.C. impedance tests. The results showed that the samples with olivine structure and 3.4V discharge platform. The tapped density of LiFePO4/C sample could reach 1.42g/cm3, and it had an initiate capacity of 144.6mAh/g at 0.2C, and 93.2% of which remained after 20 cycles. The first discharge specific capacity is 133.5mAh/g at 10C and the capacity decreased 8.76% after 20 cycles.

We reported here a novel procedure for preparing 2.5% beta cypermethrin/polyacrylate nanocapsules using miniemulsion polymerization method, in which formulation the stearic acid (SD) as assistant stabilizer and fatty alcohol-polyoxyethylene ether (n=9) sodium sulfate (AES) as emulsifier. The nanocapsules were characterized by IR, UV, transmission electron microscopy (TEM), laser particle size analyzer and TGA. It proves that beta cypermethrin nanocapsules have uniform size and core-shell structure, and the mean size is 49.1 nm. The encapsulation efficiency of nanocapsules is 84.6% and the loading capacity of nanocapsules is 13.4%. The analysis of FTIR and UV show there are no toxic organic solvent and benzene adjuvant existing in the formulation, therefore, the nanocapsule is eco-friendly. TGA analysis indicates the nanocapsule possesses release-controlled performance and could extend the duration.

Using the computer program SAFIR, the behaviors of restrained reinforced concrete (RC) beams with slab exposed to ISO834 standard fire are analyzed. The influences of three parameters (i.e., width of slab, axial restraint stiffness ratio, and rotational restraint stiffness ratio) on the beams’ behaviors in fire are investigated. Simulation results show that: (a) the axial force in the slab is much larger than that in the beam on the whole; (b) after 0.5 hour of heating the axial force in the slab decreases gradually with an increasing of the slab width ranging from 1.0 m to 2.5 m, but the influence of the slab width ranging from 1.0 m to 2.5 m on the axial force in the beam is limited; and (c) the effect of the rotational restraint stiffness ratio on the axial force in the beam/slab is very limited, but the beam’s peak hogging moment increases gradually with an increasing of the rotational restraint stiffness ratio.

Electronic structure and optical properties of non-metals (N, S, F, P, Cl) -doped cubic NaTaO3 were investigated systematically by density functional theory (DFT). The results showed that the substitution of (N, S, P, Cl) for O in NaTaO3 was effective in narrowing the band-gap relative to the F-doped NaTaO3. The larger red shift of the absorption edge and the higher visible light absorption at about 520 nm were found for the (N and P)-doped NaTaO3. The excitation from the impurity states to the conduction band may account for the red shift of the absorption edge in an electron-deficiency non-metal doped NaTaO3. The obvious absorption in the visible light region for (N and P)-doped NaTaO3 provides an important guidance for the design and preparation of the visible light photoactive materials.