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In this study, we report morphological transition of ABC triblock copolymer dissolved in special solvents that were good for the A block, poor for the B block, and marginal for the C block. The aggregate structure changes from rod to vesicle, and then to spherical superaggregates by changing the hydrophobicity of block B. Chain packing in different micelles is investigated.

For preparing 4’,4’’(5’’) di-tert-butyl-dicyclohexyl-18-crown-6 with high yield under low H2 pressure, the support, active component, promoter, reduction time and reduction temperature were studied. The catalyst structure and composition were characterized by XRD, TEM and EDS. The experimental results showed that MgO was the most suitable catalyst support because of its weaker acidity than other supports. The higher hydrogenation activity and selectivity were observed when Rh was used as the active component and Fe was used as promoter owing to the cooperative interaction. The optimum reduction temperature and the reduction time were 500 oC and 3h, respectively. The specific surface area of Rh-Fe/MgO was 133m2/g, and the Rh-Fe was well dispersed on MgO with the particle size about 20 nm. Under a low H2 pressure (4 MPa), the 4’,4’’(5’’) di-tert-butyldibenzo 18-crown-6 conversion was 78% and 4’,4’’(5’’) di-tert-butyl-dicyclohexyl-18-crown-6 yield was 53% catalyzed by Rh-Fe/MgO, which were higher than that catalyzed by single metal catalyst.

In this study, we study morphological transitions of diblock copolymer subjected to an applied external electric field by means of external potential dynamics simulation. With this method, the lamellar and the cylindrical phase aligned along the electric field directions are presented, and the kinetic pathways of lamellae are investigated.

Graduation course graduation Design is comprehensive teaching step for training undergraduates to analyze and resolve practical problem with the help of theoretical knowledge and practical skills. In this paper, superiority and current situation of petroleum geology class true topic of undergraduate course graduation design are thought and analyzed,according to improving the quality of the graduation design, put forward some reformation methods and measures. Make an attempt to explore the path of sustainable development for fitting quality education of petroleum geology undergraduates under the multiple pressures of the college expansion plan, university student employment, and industry development and so on.

Because of the relatively small number of the subtropical region building energy research, resulting in the construction of energy-saving measures in the area of building energy method is mainly imitate other regions. The building energy efficiency should be appropriate. And the crucial of the building energy efficiency in subtropical region is heat insulation processing. This paper presents the idea of a subtropical region suitable for natural ventilation insulated exterior wall structure. A new kind of suitable natural ventilation and heat insulation building structure for exterior wall in hot summer and warm winter area is proposed in this paper, which thermal properties is calculated by Maple software. And this paper demonstrates that this kind of structure is the feasibility of the structure. The result of the comparison of thermal properties of different insulating structure by using the finite difference method for unsteady heat conduction calculation presents that the insulation performance of the buildings which have the natural ventilation and heat insulation structure is better than the ones without this ventilation. In the end of paper, the authors descript the hope that this kind of structure will be further research and analysis.

The different ratios (PVA and SA) of PVA/SA blend films with cross-linking structure are successfully prepared by coagulating the mixture of sodium alginate (SA) and polyvinyl alcohol (PVA) in aqueous solution, then by treating with crosslinking agent CaCl2solution. The Surface morphology and flexibility of PVA/SA blend films were studied. The results indicate there is some strong interaction and good compatibility between sodium alginate and polyvinyl alcohol molecular. The physical and chemical properties of the PSA-80(PVA:SA=4:1) blend films are obviously improved owing to a molecular force and hydrogen bond interaction. The effects of parameters of the blend film was investigated in relation to its adsorption capability for low concentration ions Cr (VI) including such as SA content of the PVA/SA film, contact time, solution pH and temperature of solution. The results indicate that the maximum adsorption rate is 95.86% at the temperature 50°C under optimized pH 4 for 60min by PSA-80 films.

The copper-doped ZnS particles were immobilized on the surface of Hexafluorobutyl acrylate-co-methacrylic acid (poly (HFBA-co-MAA)) which synthesized by bulk polymerization electrospun nanofibers. The fluoropolymer fibers, which have around 200 nm in average diameter, of poly (HFBA-co-MAA) and are obtained by electrospinning. Zinc and copper ions are introduced onto the fiber surface by coordinating with carboxyls of MAA. After that, sulfide ions are incorporated to react with zinc and copper ions by a hydrothermal synthesis. Thus, copper-doped ZnS particles of around 100 nm in average size, are obtained and well loaded on the fiber surface. The absorption of copper-doped ZnS/HFBA-co-MAA fiber composites is at 262 nm and 326 within the ultraviolet light region. It was found that the average rate of H2 evolution of copper-doped ZnS powders slightly decreased, while the average rate of H2 evolution of copper-doped ZnS/HFBA-co-MAA fiber composites increased from the first to the third run. The average rate of H2 evolution using the copper-doped ZnS/HFBA-co-MAA fiber composites as the catalyst achieved 49.04 mL/h in the third run.

This is the brand-new century, which is a new information technology, international and comprehensive era. The pressure of looking for work is very big, thus the competition is very intense. At the same time, many high comprehensive quality talents are needed. While our strong specialized colleges and universities need more students, whose professional knowledge and knowledge of foreign language are excellent. They can stand out in job markets where there are few opportunities for employment. There are some problems in specialized foreign language development of colleges and universities, and puts forward some relevant countermeasures based on analyzing these problems.

Magnetic Fe3O4/cellulose microspheres with mean diameter of 100 μm were prepared by sol-gel transition method using ionic liquids (AmimCl) as solvent for cellulose dissolution and regeneration. Their structure , properties and morphology were analysed using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and vibrating-sample magnetometer. The results indicated that the synthesized microspheres were good sphere with a mean diameter of about 100 μm. It also showed that cellulose had been successfully covered onto the surface of Fe3O4 after the preparation. Therefore, we have provided a simple and biocompatible support for applications in the biomaterials field.

The polymer stabilized liquid crystals (PSLC) films was prepared subsequently based on the mesogenic diacrylate monomer 4,4’-bis[6-(acryloyloxy)-hexyloxy]biphenyl (BAB6). The effects of BAB6 on the morphology of polymer network as well as the electro-optical properties of the PSLC films were investigated. The helical structure of liquid crystals was observed in the morphology of polymer network by SEM. Further, a single switching process was observed at lower monomer concentration in this study compared with the former publication. When BAB6 concentration reached 7 %, the response time and contrast ratio of PSLC film were 7 ms and 16.8, respectively.

Infrared thermal wave detection technology has been found to be a new type of wide attention non-destructive testing (NDT) method due to its non-contact, non-destructive, rapidity, wide imaging field and advantages of direct observation. Key technologies and the latest research progress of the infrared thermal wave technology in parts defects are reviewed in this paper. The key technologies include the heat stimulator, infrared thermal image processing, heat transfer analysis and etc. The existing problems of the technology are also pointed out.

Ultrafine α-Fe2O3nanoparticles have been synthesized by a facile hydrothermal method. The products were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM). The diameter of the as-obtained α-Fe2O3nanoparticles is about 6.8 nm on average. The solvent have great effect on the morphology of the final products. Furthermore, the effect of ultrafine α-Fe2O3nanoparticles on the thermal decomposition of ammonium perchlorate (AP) was investigated by thermal gravimetric analyzer (TG) and differential thermal analysis (DTA). The thermal decomposition temperature of AP in the presence of α-Fe2O3nanoparticles was reduced by 99 °C.

Yarns were seen as having a concave-convex structure consisting of a main frame and a twisting according to their morphological structure and property. Simulation model of yarns was built by adopting the virtual reality technique and frame modeling method and texture mapping was used to enhance its trueness. With the surface algorithm NURBS and based on the twisting feature of yarns, the appearance model of yarns can be established by moving and rotating the section of yarns and fitting the control vertex obtained. The experiment shows that both the two methods realize the appearance simulation of yarns and meet the expected effect.

TiO2 doped with C was obtained by way of immersion and calcinations method by using citric acid (CA) as dopant material.，and characterized by using XPS、XRD, UV-Vis, FT-IR and SPS. The results of analysis and characterization showed that C substituted partial Ti atoms in the lattice of TiO2 and formed Ti-O-C structure. The photocatalytic properties of C-TiO2 photocatalysts had been evidently improved as a result of a noticeable shift to visible region and the enhancement of the charge separation efficiency. The doped carbon lowers the band gap and expends the absorption of visible light region. CO2 was photocatalytically reduced to form HCOOH by the best C-TiO2-3/1-600 nanoparticles under the irradiation of the simulated daylight lamp. Methanoic acid yield may achieve 2633.98μmol/g-Cat when irradiation time is six hours.