Advanced Materials Research Vols. 912-914

Abstract: The purpose of this study is to have a better understanding of the mechanical characteristics of high performance concrete which is produced by mixing reinforcing fiber controlled by high temperatures with fly ash. After heating up the concrete, its appearance, demolition mode, residual compressive strength, weight reduction ratio and other mechanical characteristics were measured. To improve the mechanical characteristics of concrete, it was mixed with nylon, polypropylene, steel fiber and fly ash. The specimen was exposed to 100 ~ 800°C and its crack control, spalling prevention and other mechanical characteristics were reviewed. When the high performance concrete was exposed to 600°C or higher, its residual compressive strength dropped but its weight reduction ratio was significantly higher than it was heated before.

Abstract: The compositions, electrical properties and microstructures of zinc oxide ceramics with various 46.6ZnO-20Na₂O-33.4P₂O₅ glass oxide additions prepared by solid-state method have been investigated. The structure of the materials is studied using X-Ray diffraction, and the microstructure is analyzed using scanning electron microscopy. The results indicated that the electrical properties were associated with the amount of 46.6ZnO-20Na₂O-33.4P₂O₅ glass oxide additions and the sintering temperatures. The correlation between the microstructures, oxide additions and the sintering temperature was also discussed. From the results of electrical properties measurements, zinc oxide ceramics with various 46.6ZnO-20Na₂O-33.4P₂O₅ glass oxide additions exhibits a good electrical behavior, which can be a suitable candidate material for electronic device applications.

Abstract: The characterization of microstructure and basic properties of domestic butyl rubber 1751 ( IIR 1751) was performed with different testing , such as 1H-NMR spectrum, gel permeation chromatography, dynamic mechanical analysis, thermal gravimetric analysis and differential scanning calorimeter. And the comparison with Butyl 268 and Butyl 301 was made. The results showed that IIR1751 had a narrower molecular mass distribution, lower number-average molecular mass and lower weight-average molecular mass. The unsaturation degree of IIR1751 was close to Butyl 268 and Butyl 301. Its thermal stability was higher than the other and its ash content and volatile matter content was lower. Its glass transition temperature was same to Butyl 268’s, which was slightly higher than the Butyl 301. Dispersion of carbon black in IIR1751 vulcanizates was poor, but IIR1751 vulcanizates had good processing property, had a longer scorch safety period and fast curing rate. Its fatigue performance was good and its mechanical properties can achieve a better balance.

Abstract: Gypsum waste from building constructions is a material which can contaminate the soil and groundwater if is disposed directly in the soil or landfill without any control. In Brazil, these wastes are considered a recycle and/or recovery material, but the research of gypsum plaster recycling are very few at this moment. In this way, this work presents the microstructural characterization of two types of recycled plaster. The recycled plaster was produced by a grinding and calcination the building construction waste. Microstructural characteristics were evaluated by SEM observations. The results show similarities between crystals of recycled and commercial plasters.

Abstract: Schizolobium amazonicum is being much used in Brazil for several purposes because, besides being a native Brazilian wood specie, has important features such as low density and small incidence of natural defects. At this point, researches with the purpose of obtaining further knowledge of their properties are being conducted to better targeting their use. The aim of this research is to evaluate the modulus of elasticity of structural size pieces of Schizolobium amazonicum wood using the technique of transverse vibration. Tests were carried out using 30 pieces (standard moisture content 12%) with sizes of 3 cm x 15 cm x 2.5 m. The average value of elastic modulus determined for lumber of Schizolobium amazonicum was interesting to its low specific gravity.

Abstract: Novel ionic polymer-metal composites (IPMC) based on sulfonated polyimide (SPI) was firstly developed by employing a more convenient, time-saving and effective electroless plating method. Their overall structure and the distribution of metal particles in the membranes were examined by scanning electron microscopy (SEM) attached with energy dispersive X-ray spectrometer (EDS). The actuation of the prepared IPMC was evaluated. The analytical results confirmed that platinum are successfully deposited on the membrane. Under DC voltage excitation, the IPMC undergo larger displacement compared with Nafion-based actuators. The larger displacement of the IPMC was considered to be the result of the higher concentration of sulfonyl groups, larger ion exchange capacity, and consequent larger volume of water moving.

Abstract: Due to the natural condition of the sudden temperature drop when the cold wave strikes the north part of China in winter, especially XinJiang province, the asphalt pavement structures need to be compared. Based on the pavement structures of the test road sections andthe domestic major pavement structures in other provinces, seven pavement structures were chosen. The numerical simulation of these seven pavement structures was performed and the force situations were analyzed respectively under the condition of extreme climate environment, which is the condition of cooling 40 °C from 0 °C in winter. The analysis of the temperature-load coupling of these pavement structures from seven different base forms were conducted. The comprehensive comparison was also made, such as stresses and strains at the bottom layer of asphalt, the stresses of the base, the shear stresses of the asphalt layer, and the compressive strains of the top of base, etc., in order to choose the preferred and most adapted asphalt pavement structure form.

Abstract: Aim:Doxorubicin-induced cardiotoxicity limited its clinical utilization in oncology. In this study, Dox was entrapped into PEG-PLGA Nanoparticles, cardiotoxicity of Dox or PEG-PLGA-Dox was investigated in rats. Materials and methods :PEG-PLGA-Dox was prepared via modified single emulsion method. Its characterization including size, Drug loading capacity (DLC), entrapment efficiency (EE) were estimated. The cardiotoxicity of PEG-PLGA-Dox was assessed on SD rats via echocardiography and biochemical indicators compare to free Dox and physical sodium. Results:The average diameter of PEG-PLGA-Dox is around 200 nm, with DLC about 10%.After administered PEG-PLGA-Dox, the ratio of heart weight to body weight decreased not as significant as Dox group, level of serum parameters and echocardiography parameter also decreased little compared to the Dox group. Conclusions:After entrapped into PEG-PLGA nanoparticle, Dox-induced cardiotoxicity was reduced significantly.

Abstract: To improve the performance of sulfonated polyimide (SPI) membrane, especially to heighten water stability, γ-rays irradiation-induced crosslinking is used to modify the SPI membrane. The effects of radiation crosslinking on SPI membrane are investigated. Their physical properties, membrane morphology, proton conductivity, membrane stability and mechanical property are measured and reported. In this study, 24 hours radiation treatment endow the SPI membrane (SPI-24h) with the optimum performance, remarkably improved the water stability with only slight sacrifice in proton conductivity.

Abstract: The hierarchical and ordered porous nanostructured carbons (HOPNCs) have a very wide application in catalysis, adsorption separation, energy storage and other fields. In this paper, the HOPNCs was prepared through a dual-template method and the resole resin as the carbon precursor,followed by the ethanol solvent evaporation induced self-assembly process. The morphology and microstructure of the as-made products were characterized by SEM, XRD, TEM,and physical adsorption instrument. The results showed that the orderliness of mesoporous carbon materials are significantly enhanced while the ratio of P123/F127 was 1/3,a proper low concentration of template and alcohol solution was helpful to the solvent induced selfassembly formed ordered mesoporous structure of nanocarbons.The as-made HOPNCs have large pores of 200 nm or so, mesopores of 8 and 3 nm or so, the pore volume of 0.2527 cm³/g , the BET surface area of 510m²/g.