Advanced Materials Research Vols. 562-564

Abstract: VC-co-VAc-OH material was used to prepare flat-sheet membranes on the non-woven fabrics via phase inversion method. And the membrane preparation conditions（polymer content, the content of additive, environmental temperature, relative humidity, evaporation time, coagulation temperature, coagulation time, immersing time of non-woven fabrics in solvent, and exposure time of non-woven fabrics in air）were discussed systemically by orthogonal method. Finally, the membrane prepared under the optimum condition showe higher pure water flux (287.9 ml•cm^-2•h^-1) and good retention of Bovine serum albumin (BSA) (87.4 %).

Abstract: The tungsten oxideWO₃ thin film was prepared by sol-gel process through peroxotungstic acid (PTA). The crystal phase and surface morphological features change at different annealing temperatures. The WO3 thin film is amorphous at 300 °C. When the annealing temperature is increased to 400 °C, it becomes monoclinic phase. The phase begins to become triclinic at 550 °C. The phase then changes to orthorhombic phase at 750 °C. With the increasing of the annealing temperature, the continuum of the WO3 thin film is broke and the gabs among grains become larger. The WO3 thin film is almost disappear after annealed at 850 °C.

Abstract: NiZnO films were grown on sapphire substrates by metal-organic chemical vapor deposition (MOCVD). Then the films were annealed in vacuum at different temperatures for 1h. The UV emission peak was blue shifted in the photoluminescence (PL) spectra and a dramatic shift of (002) diffraction peak to higher angle was observed in X-ray diffraction (XRD) pattern with the increasing anneal temperature. It showed the band gap and the lattice parameter of NiZnO had been affected by anneal in vacuum. From the X-ray photoelectron spectroscopy (XPS) of the NiZnO film, we can find that the anneal temperature had an important effect on the content of each element in NiZnO quantificationally. In addition, the value of x in NiZnO varied slightly with the anneal temperature increasing. The above phenomena indicated that anneal in vacuum could slightly adjust the percentage of Ni indirectly in NiZnO film and offer a good idea in NiZnO devices facture.

Abstract: Ni-3.3wt.%B alloy solidified at different undercooling by glass fluxing has been studied. The as-solidified structure is mainly controlled by the undercooling for eutectic solidification, ΔT₂, instead of ΔT₁, the undercooling for primary solidification. For ∆T₂2 ≥145±5K, three recalescence peaks appear in cooling curves. If ∆T₂2≥145±5 K, two kinds of dot phases occur. Further analysis declares that, the regularly distributed dot phases with larger size come from the transformation L→Ni₂₃B₆+Ni, whereas, the irregularly distributed ones with smaller size come from Ni₂₃B₆→Ni₃B+Ni. Both of them have a contribution to strengthen the mechanical property.

Abstract: Blending PPO and POE-g-MAH assisted by SCCO2 has been investigated. The in-line rheological behavior of PPO and POE-g-MAH containing SCCO2 were studied with the slit die and self made in line rheological testing system. The effect of SCCO2 on the reduction of shear viscosity of PPO is more obvious than that of POE-g-MAH. The shear viscosity of PPO reduced 36.7% with addition 4wt% CO2. Morphology of blends was inspected by SEM. The sizes of POE-g-MAH disperse phase decreased with the contents of CO2 increasing. As a result, the impact strength of blend is improved from 43.5KJ/m2 to 100.9KJ/m2 due to introduce 4wt% SCCO2 for PPO/POE-g-MAH (85/15) blends.

Abstract: This paper mainly researches the compatibilization effect of γ-radiation on PP/TMPTA/TPU blends. With trimethylolpropane triacrylate (TMPTA) as compatibilizer, different ratio PP/TMPTA/TPU blends are prepared via melt mixing by using a twin-screw extruder, and then the blends are irradiated(radiation dose≤25kGy) by ⁶⁰Co-γ radiation source in different atmospheres. The effect of γ-radiation on the mechanical properties, dynamic mechanical properties and morphology of the blends is investigated. The results show that the compatibility of PP/TMPTA/TPU is improved by moderate dose γ-radiation (especially when radiation dose is 25kGy in air and 10kGy in vacuum), and γ-radiation functions similarly in the improvement of mechanical properties of the blends in the two atmospheres.

Abstract: The Si¬₂ON₂-SiC ceramic was fabricated by pressureless sintering method. In this paper we researched the effect of SiC content (50%, 70% and 90%) on the performance of silicon oxynitride bonded silicon carbide ceramics. Through testing and analyzing the SEM, XRD, density and porosity of the final silicon oxynitride bonded silicon carbide ceramic samples, the results show that: changes in SiC content not only affect the bulk density of the composites but also affect the phase composition and the microstructure of fracture surface. The most compactness experimental product is sintered at1500°C containing 50wt% SiC.

Abstract: By welding thermo-simulation and actual welding practices, the microstructure and properties of low carbon bridge steels has been studied with the aid of optical microscope, scanning electron microscope. The experimental results show that by the oxide introducing melting technology there are many complex inclusions composed of oxide containing Ti and MnS. These inclusions are spherical and they are distributed homogeneously. During the welding thermo-simulation these oxide inclusions will promote the nucleation of acicular ferrite and make the microstructure in HAZ finer. Therefore the toughness in HAZ is good whether in welding thermo-simulation even if the heat input reaches to 200kJ/cm. In actual welding the heat input is 88kJ/cm and the low temperature impact energy still can reach 110J.

Abstract: TheY2O3 partially stabilized in ZrO₂ and the MgO partially stabilized in ZrO₂ ceramic coating were sprayed by APS on 45 steel substrate, and the tribological properties of coatings were tested on the MMW-1 vertical universal friction and wear tester at room temperature and dry sliding conditions. With FA2004 electronic balance, the amount of the loss of coating is measured. The wear of the coating surface morphology is observed by scanning electron microscopy. The test results show that wear resistance of Y-PSZ coating is better than Mg-PSZ coating. There are some cracks, voids and peeling pits in two kinds of coating. A material transfer is occurred during the friction and wear.