Applied Mechanics and Materials Vols. 448-453

Abstract: The biodegradable microcapsules based ethyl cellulose (EC) for a controlled delivery of Argy Wormwood solution (AWS) were prepared by emulsionsolvent evaporation method using ethyl acetate as solvent. This study examined the effect of the ratios of core to shell on the size of microcapsules. SEM images of microcapsules showed uniform spherical structures with smooth surfaces with a particle size distribution of 100nm2μm. Core-shell, hetero-structures were confirmed using optical micrograph. The chemical structure of the microcapsules was determined by FTIR.

Abstract: This study is concerning the influences of nitrogen content and aging precipitates on pitting corrosion resistance properties of high nitrogen austenitic stainless steel (HNS) through potentiodynamic polarization method. The microstructure of aged HNS is analized by scanning electron microscopy (SEM). The main results obtained are as follow: the formation of intergranular, cellular Cr₂N and intermetallic χ precipitates makes the depletion of Cr and Mo in the matrix and deteriorates the resistance to pitting corrosion in aged specimens. Cr₂N starts to precipitate in the form of lamellar structure to cellular precipitates, the pitting corrosion drops to about 0 V_SCE. HNSs perform the same tendency that the pitting corrosion potential firstly decreases then increases and reduce to the minimum value at nose temperature. All the pitting corrosion potential of HNS-B aged for 2h at different temperature presents more than that of HNS-A. The pitting corrosion resistance is mainly controlled by nitrogen content before great precipitates of cellular Cr₂N and intermetallic χ phase rich in Cr and Mo. It is also mainly controlled by the content and the type of precipitates after great precipitates of cellular Cr₂N.

Abstract: Movie shooting caused large quantities of oil emissions into the surrounding frequently , the water quality could be contanminate. EPDM rubber was chosen as the main matrix to prepare foam oil absorption material by simple melt blending and molded foaming. The impact of DCP and AC on oil-absorbing properties of materials was studied, and the optimal amount of DCP and AC was 1.5Phr and 10Phr; Through foaming process, the oil absorbency was greatly improved, and the maximum oil absorbency was 12.73g/g which was increased by 566.5% compared to the corresponding solid material. This composite is an inexpensive, convenient and high efficiency material for removing oils from movie shooting.

Abstract: This work reports melamine resin was modified with siloxane, Polyvinyl alcohol (PVA) and polyethylene glycol (PEG) to improve its structure and properties, and accomplished a wide research and study on the effect of different reaction conditions, including temperature, PH and solid contents. Using infrared spectroscopy (FTIR), thermogravimetric analysis (TG) and DSC to analyzed the samples and study their composition and performance. The results showed that siloxane, Polyvinyl alcohol and polyethylene glycol (PEG) modifier can make the performance of the melamine better than unmodified ones.

Abstract: A new kind of graphite oxide (GO)-coated glass wool /EVA/EPDM foaming composite was prepared by melt blending.we choose it as absorbent, methylene blue (MB) as target pollutant to study its adsorption behavior. The foaming composite had a certain adsorption capacity of MB in the water. With the increase of proportion of GO-coated glass wool, the MB absorbencies increased.

Abstract: In order to resolve the dye pollutions in media industry, a new kind of glass wool modified by graphite oxide was prepared. This material could easily fill the filtration column and had good performance on the adsorption of methylene blue. Four kinds of samples like the glass wool modified once, twice, three times by graphite oxide and unmodified were used in our study. According to the dynamic adsorption experiments, the effective adsorption time of the glass wool modified three times is 95 min which is almost 4 times the length of the effective adsorption time of unmodified glass wool.

Abstract: Molecular dynamical (MD) simulations were performed to study the structure sensitivity of H₂O adsorption on adsorption different Bi₂WO₆ and grapheme-supported Bi₂WO₆ surfaces. Results show that stronger interaction happens between H₂O and Bi₂WO₆ (001) than the interactions (between H₂O and Bi₂WO₆ (100) and between H₂O and Bi₂WO₆ (010)), and O atom of the surface acts as the active site for H₂O adsorption. The adsorption modes and locations of H₂O on G-Bi₂WO₆ distinct with those on Bi₂WO₆ surfaces. The maximum adsorption amount of H₂O on graphene is under 333K and 373K, with the value of 12.0403×10^-5mol/m² and 12.0538×10^-5mol/m². The maximum adsorption amount of H₂O adsorption on Bi₂WO₆ (100), G-Bi₂WO₆ (100), and G-Bi₂WO₆ (001) is under 303K, 303K, and 333K, with 6.4079×10^-5mol/m², 9.1096×10^-5mol/m², and 11.1917×10^-5mol/m², respectively. Meanwhile, the maximum adsorption amount of H₂O adsorption on G-Bi₂WO₆ (010) is under 353K and 373K, with the value of 10.0452×10^-5mol/m² and 10.5417×10^-5mol/m². Results point out the optimal catalyst and the most appropriate pressure and temperature for H₂O interacting to Bi₂WO₆ and grapheme-supported Bi₂WO₆.

Abstract: In this paper, four models of PVC composites reinforced with glass fabric were designed based on the arrangement of the V-structure, using V-structure discontinuous glass fabric as the sandwich structure and PVC resin as matrix. The acoustic insulation properties of the composites with V-structure discontinuous glass fabric as the sandwich structure were analyzed with a two-channel acoustic analyzer. The results show that the orientation of the V-structure has a strong effect on the acoustic insulation property. In the case where the raw material, thickness and density of the V-PVC composites are almost the same, the composite with the opening of the V-structure toward the source of sound shows better acoustic insulation than that with the opening of the V-structure away from the sound source. This difference is even more pronounced with increasing layers of glass fabric.

Abstract: Chitosan/Poly (vinyl alcohol) (CS/PVA) composite nanofibrous membranes with diameter between 150-350 nm have been fabricated by electrospinning. The effect of contact time, temperature, pH and concentration of triclosan on the adsorption capacity of the membranes were investigated. The equilibrium adsorption capacity of triclosan on CS/PVA nanofibrous membranes was 61.61 mg/g. The favorable pH for triclosan adsorption was pH 6. After five regeneration cycles, the removal rate of triclosan maintained above 67%. The adsorption of triclosan on the membranes fitted both Freundlich and Langmuir isotherm model. Its adsorption kinetics followed a pseudo-second-order model.

Abstract: Structures of Dibenzo-18-crown-6(DB18C6), Di-methyl-dibenzo-18-crown-6(DMB18C6), Di-tert-butyl-dibenzo-18-crown-6(DTBB18C6), Di-tert-amyl-dibenzo-18-crown-6(DTAB1C6) and their complexes with strontium ion were optimized based upon DFT at B3LYP using 3-21G basis. The binding energy of crown ethers with Sr²⁺ was calculated according to the energy of optimal structures. The complex strength increased gradually from DB18C6 to DTAB18C6, which could be related to the changes of cavity size of crown ethers and electron density on the crown rings. Addition and extension of alkyl groups on DB18C6 could enhance the combination between crown and Sr²⁺.