Advanced Materials Research Vols. 152-153

Abstract: Prepared rare-earth La modified amorphous ribbon by doping Rare-earth La in Fe78Si9B13 amorphous alloy. Investigated rare-earth content and temperature, as well as their influence on the magnetic induction effect and it’s amplitude. The results show that, when magnetic field is less than 1356 A / m, with the increase of Rare-earth content ,the magnetic induction effect first increased and then decreased, when the magnetic field strength greater than 1356 A / m, the Rare-earth content influence little on magnetic induction effect , changing amplitude of magnetic induction effect shows first increased and then decreased with increasing Rare-earth content; temperature influence little on the magnitude of magnetic induction effect.

Abstract: A FEA model, based on the crystal plasticity theory, was established to study the mechanical behavior of titanium, and the microstructure evolution during deformation. Simulation on the dynamic tension of a commercially pure polycrystalline titanium at different strain rates and temperatures showed that the model can well describe the stress-strain behavior of titanium, the simulated results also revealed the contribution of different slip systems to the deformation of titanium, and the grain reorientation evolution caused by the crystallographic slipping.

Abstract: In this paper, gold nanoparticles with branches were prepared in aqueous solutions using seed-mediated growth method. The mean diameter of the seeds chosen for these studies is 6~8nm. The influence of reducing agent used in synthesis gold sphere as seeds was investigated. A reaction mechanism of fabrication gold nanostar particles was systematically described. The nanoparticles synthesized were characterized by transmission electron microscopy (TEM) and UV-vis spectroscopy. In order to investigate their optical property, Surface Enhanced Raman Scattering (SERS) spectrums were tested, which showed quite good Raman enhencement.

Abstract: For the complexity of convective term, the interior heat transfer is important for the engineering testing of heat conduction of fibrous porous materials. In this paper the heat transfer through the body of fibrous porous materials was simulated with finite volume method. By the simulation, it is found that the total heat flux through the body of fibrous porous materials is a linear function of the thermal conductivity when it is measured by the guarded plate, and some constants in the linear function are related with the thickness and permeability coefficient of the sample. The simulated data are employed to fitting the variation curves of the total heat flux with thermal conductivity, thickness and permeability coefficient, respectively. The improved calculating formula of thermal conductivity for fibrous porous materials is established based on the fitting estimation. Through the experimental, it is demonstrated that the improved calculating formula is more accurate than the original one, which is based on the assumptions of single component continuum material and one dimensional heat transfer.

Abstract: The feasibility and operation characteristics of anaerobic fermentation biohydrogen production in a continuous stirred tank reactor (CSTR) were investigated for treating molasses wastewater. The research indicates that the reactor has the capacity of continuously producing hydrogen in an initial biomass (as volatile suspension solids) of 17.74 g/L, temperature of (35±1) °C, hydraulic retention time (HRT) of 6 h, and the reactor can start up the ethanol-type fermentation in 12 days and realize stable hydrogen production. Furthermore, the CSTR reactor enjoys a favorable stability even with an organic shock loading. When the organic loading rate (OLR) increased from 8 kg/(m3•d) to 24 kg/(m3•d), the CSTR system reached a new steady state within 9 d. The hydrogen yield and COD removal increased from 3 L and 8% to 12 L and 20% respectively with the hydrogen content of 47 %.

Abstract: In this article, for a better understanding of the viscosity changes in LPMC (low pressure sheet molding compounds), the thickening mechanism of crystalline polyesters was studied. And by means of varying the content of crystalline polyester resin, the thickening effect on resin paste was investigated, too. Results gained during experiments showed that there existed three kinds of functions acting in the process of thickening: swelling, hydrogen bonds and induction crystallization. The thickening effect was excellent when the amount of crystalline polyester resin was 3%. This research supports the producing process for LPMC with theory basement.

Abstract: Dynamic tensility experiment has been done to research Galvanneal coating fracture of Galvannealed steel sheet with in-situ SEM observation and Galvanneal coating Fracture has been analysed. It is been thongt that desquamation takes place at the interface of substrate /Γ phase. The Fracture of Γ phase is serrated and its thickness is hundreds of nano-metres. The Fracture shape of Γ phase is different from other phases of of the galvanneal coating.

Abstract: Effects of SiC particle and holding time on microstructure evolution of SiCP/AZ61 composites during semi-solid isothermal heat treatment method were studied, and evolution mechanism of semi-solid microstructure of composites was discussed. The results indicated that the process of microstructure evolution of SiCP/AZ61 composites by the isothermal holding at the temperatures of 595°C for different times (0min~90min) experienced in succession the rapid merging of the secondary dendritic arms →large massive structure→melting and separating of the local grain boundary →spheroidization of the gains →slowing growth of globular microstructure. Synthetically, after isothermal holding at 595°C for 30min to 60min the favorable semi-solid microstructure can be obtained; Compared with the monolithic AZ61alloy, microstructure of SiCP/AZ61 composites during semi-solid isothermal heat-treatment was finer as a result of entering of Sic particle, and with the increasing of SiC particle volume fraction, globular gain size was smaller.

Abstract: A dilute copper alloy of Cu-0.45wt%Al -0.066wt %Y was selected to fabricate nanometer size Al2O3 particles dispersion-hardened composite layer by using aluminizing-internal oxidation technique. The structure and size of the precipitate, interface structure, lattice parameter mismatch and morphology were investigated by means of high resolution transmission electron microscope, analytical transmission electron microscope and image processing by VEC software. Results show that two different size and structure nano-alumina precipitate were identified as α-Al2O3 and γ-Al2O3 respectively during different processing. The precipitates possess semi-coherence or coherence interface structure to matrix with typical loop-loop contrast. The cubic γ-Al2O3 precipitate in certain crystal plane and direction parallel to the matrix。

Abstract: The sulfonated-polyethersulfone (SPES)/nano-TiO2 composite ultrafiltration (UF) membranes were prepared by phase inversion method with nano-TiO2 as additive. The TiO2 self-assembly on the SPES membrane was confirmed by FT-IR and the isoelectric point’s analysis (IEPs). The electrokinetic phenomena of composite membrane in the different single electrolyte solution were investigated by the streaming potential method. The results showed that the IEP of the SPES-UF membrane modified by nano-TiO2 shifts from 3.5 to 2.9, and the composite membrane shows a stronger electronegativity, which indicates the antifouling performance improvement of the SPES-UF membrane modified by nano-TiO2. The valences of the cations and anions have an important influence on the streaming potential of the composite UF membrane.