Advanced Materials Research Vol. 898

Abstract: Through the scanning electron microscope and energy spectrum analysis of vanadium slag after calcination at different temperatures of Panzhihua Iron and steel in industrial production, analyzed the change of morphology and composition of the various main phase, Focuses on the change process of two main vanadium containing phase which are vanadium spinels and calcium vanadate. The vanadium spinels into calcium vanadate optimal temperature range is 800 ~ 900 °C, and provides a theoretical basis for the extraction process of vanadium, which can further improve the industrial production of vanadium.

Abstract: Novel dendronized polymers bearing azobenzene moieties in the side chain, poly (2, 5-bis {[3, 4, 5-tri (4-methoxy-4-oxyhexyloxy azobenzene) benzy oxycarbonyl} styrene), has been successfully synthesized. These polymers were characterized by 1H NMR, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), polarized light microscopy (PLM), and one-dimensional wide-angle X-ray diffraction (1D XRD). The effects of molecular weight on liquid-crystalline behavior of these dendronized polymers were also investigated. The results show that the low molecular weight polymer P1 exhibits smecitc A (SmA)-like structure at lower temperature and nematic phase at higher temperature. Further heating P1 above the highest phase transition temperature, the sample becomes isotropic state. With the increasing of molecular weight, the high molecular weight polymer P2 exhibits more versatile intriguing liquid crystalline properties. The sequence of phase transitions of P2 follows: 2D centered rectangular columnar phase (ΦR) scaffold of main-chain and SmB-like structure of side-chain 2D centered rectangular columnar phase (ΦR) scaffold of main-chain and SmA-like structure of side-chain 2D centered rectangular (ΦR) scaffold of main-chain and isotropic side-chain 2D long-range-ordered hexagonal columnar phase (ΦH) of main-chain and isotropic side-chain. The 2D long-range-ordered hexagonal columnar phase (ΦH) of P2 still remains before the sample is completely decomposed.

Abstract: A LiNH₂/MgH₂ (1:1) complex was prepared by mechanical alloying and the effects of Ti and TiF₃ on the characteristics of hydrogen storage were investigated. It was found that LiMgN and Li₂NH phases exist as the main phases in the LiNH₂/MgH₂ (1:1) complex and that Mg (NH₂)₂ and NH₄HF₂ phases appear when TiF₃ is added. The onset temperature of hydrogen desorption was reduced with increasing mill time, and the hydrogen saturation absorption temperature for the LiNH₂/MgH₂ complex decreased about 30°C with the addition of Ti and TiF₃. Ti and TiF₃ as catalysts are favorable for reducing the dehydrogenation temperature. The addition of TiF₃ can also facilitate the increase of hydrogen desorption for the LiNH₂/MgH₂ (1:1) complex.

Abstract: The Chinese herb residue (CHR) fiber obtained by blasting through a continuous steam explosion device, and recycled acrylonitrile-butadiene-styrene (ABS) were blended to prepare reABS/CHR fiber composites by a vane extruder. Three kinds of thermoplastic elastomers: POE, SEBS and TPU were used to toughen composites. The results of toughening effects, mechanical properties and thermal stability properties show that: there were significant effects of these agents on impact strength; the compatibility not only affects toughening result, but also other properties; the best toughening agent for reABS/CHR fiber composites is TPU.

Abstract: The thermal oxidation kinetics of natural rubber containing hydrazine dihydrochloride or hydrazine sulfate used as tackifier were studied, and the effective storage time of natural rubber containing tackifier was predicted with a method of heat accelerated storage aging. The results show that the thermal oxidation activation energy of natural rubber containing hydrazine dihydrochloride is 105.6kJ/ mol, being a little higher than that (104.7 kJ/ mol) of the control. The thermal oxidation activation energy of natural rubber containing hydrazine sulfate is 103.1kJ/ mol, being a little lower than that of the control. The effective storage time of natural rubber containing hydrazine dihydrochloride is 13.4 years at 30°C,27.0years at 25°C, and 55.9years at 20°C. The effective storage time of natural rubber containing hydrazine sulfate is 11.6years at 30°C,23.0 at 25°C, and 46.8years at 20°C.The effective storage times of natural rubber containing two tackifiers hydrazine dihydrochloride or hydrazine sulfate are higher than that of the control at the same condition.

Abstract: Microcellular foaming behavior of polypropylene/polystyrene (PP/PS) composites with or without the addition of nanoclay was compared in an extrusion foaming process by using supercritical CO₂ as the foaming agent. The influence of CO₂ content on foaming of the composites was investigated in the study. Our experiment results demonstrated that the introduction of nanoclay dramatically improved the foaming of the PP/PS blends with increased cell-population density and decreased cell size. With the increase of CO₂ injected in the foaming process, cell-population density of the foam samples further increased.

Abstract: In present study, artificial neural network (ANN) was used to predict the tensile moduli of carbon nanofibers (CNF)/epoxy composites. The tensile properties of CNF/epoxy composites made by different dispersion technique were measured by tensile test. It was found that the tensile properties are seriously affected by the CNF fraction, ultrasonication time and mechanical stirring time. According to the test results, ANN was trained and used to predict the tensile moduli of CNF/epoxy composites. By compared the predicted values with the experimental data, it was demonstrated that the back propagation ANN model is a promising tool for prediction of properties of composites.

Abstract: With the purpose of development of zinc flow cells/batteries, a fundamental study on the cell plate stress distribution, power generation performance and the changes of the internal material before and after the test was carried out in a single zinc flow cell system. The results show that locations between the main channels and the reaction zone area are prone to leakage, the cell power performance is mainly influenced by ohmic losses, the total generating capacity depends on the zinc quantity in the cells and the quantity of electrolyte in the circulatory system, the zinc granule surface becomes more microporous when it comes to the power stage, and the catalytic layer repeated wetting and drying may be the important reason to influence the cycle life. This research is basis for development of higher power and larger capacity zinc flow cell systems.

Abstract: The anodic current-potential behaviors of PS fabrication by doubled-cell electrochemical etching method have been studied. There are three reaction regions: porous silicon formation region, a transition region and electropolishing region in I-V curves. Polishing current and the HF acid concentration has a directly proportional relationship, the electropolishing current of silicon increased with the increase of the concentration of HF, in a certain concentration range. The electropolishing current of silicon increased with increasing the sweep rate on the condition of the same HF concentration.

Abstract: La_0.9Sr_0.1Ga_0.8Mg_0.2O_2.85 (LSGM) electrolyte films were successfully prepared by slurry spin coating method on porous La_0.7Sr_0.3Cr_0.5Mn_0.5O_2.75 (LSCM) anode substrates. Ethyl celluloses content, coating cycles for slurry spin coating on the fabrication LSGM electrolyte films were investigated. The compatibility between LSGM and LSCM powders, microstructures and electricity conductivity of fabricated LSGM films were examined using XRD, SEM and electrochemical workstation. The film with good apparent morphology and electrical conductivity were obtained when the operating parameters were setted as the content of ethyl cellulose 10wt%, and the coating cycles 5.