Advanced Materials Research Vols. 239-242

Abstract: Yttrium Aluminum Garnet (Nd:YAG) transparent ceramic doped with Nd have predominantly chemical stability, excellent optical quality and high temperature stability, it is becomeing a substitute for single crystal, had already become new generation laser material, have important strategic sense in the laser and the superelevation powders laser system. Al(NO₃)₃·9H₂O, Y₂O₃, Nd₂O₃,(NH₄)₂SO₄ and NH₄HCO₃ are raw material, TEOS is additive and ethylene glycol(EG). Nd:YAG precursor powders witch is Homogeneously dispersed, little agglomerated, pure YAG phase, different Nd³⁺ doped density were prepared by the co-precipitation method. The Nd:YAG ceramic powders were characterized by TG-DTA, XRD, FT-IR.

Abstract: Crack will occurs when concrete structure under external load, temperature change, the crack may reduce the service life of concrete structure, to the macrocrack, there are many mature repair method, but microcrack is difficult to detect and repair. Self-healing techniques provide reliable and effective choice to microcrack repair. The paper reviewed the development of self-healing techniques, and analyzed the prospect of this field.

Abstract: Novel iron (II) complex C₂ has been prepared by treatment of the ligand C₁ with FeCl₂ in THF solution. The complex C₁ was characterized by MS and ¹H-NMR and complex C₂ was characterized by MS and element analyze. Activated by MAO, complex 2 exhibites very high activity and produces high molecular weight polyethylene. The molecular weight distribution measured by gel permeation reached 2.1 to 2.4. the GPC profile of PE obtained and High melting points measured by DSC indicates indicates that the polyethylene produced by complex C₂ is high linearity and high crystallinity.

Abstract: Photocatalytic is a developed technology in recent years for the wastewater treatment which is a new advanced oxidation technology. Stable, durable and highly active Nano-TiO₂ is photocatalytic technology to be practical needs to solve, and also there are the important research hotspot.This paper adopts titanium sulfate and ammonia as raw material with nut shell activated carbon as a carrier was highly active load type, and activated TiO₂ liquor X-3B simulation wastewater as the object of the degradation factors.

Abstract: The material pulse flow structure within the fluidized dense phase pneumatic conveying of flyash powder was studied using the Electrical Capacitance Tomography (ECT). Decomposition of the bulk density levels within the pipe cross-sectional area were obtained and statistical analysis of bulk density waves were performed. The results suggest that the pulse amplitude and duration obeyed the Weibull and lognormal distributions. In addition, bulk density factor was found to have a linear relationship with pulse amplitude; however, it is independent of pulse duration.

Abstract: The wool was pretreated with Fenton reagent in this paper, on this basis, 4-hydroxy benzaldehyde and concentrated nitric acid were used to discuss the dye-free coloration deeply. It was analyzed comparatively through a series of experiments on the wool before and after Fenton reagent pretreatment, and the effects of concentrations, temperature and time on the coloration were further discussed. The experiment indicated that, compared with untreated wool, the color of wool with Fenton reagent pretreatment was deeper and the coloration rate was quicker. It realized good coloration at lower temperatures, which achieved the goal of saving energy and emission reduction. The optimal conditions were that concentrations of 4-hydroxy benzaldehyde and concentrated nitric acid were 2.5% and 3% respectively, reacting time was 90min, and reacting temperature was 70°C.

Abstract: Arrays of ordered carbon nanotubes (OCNT) was synthesized successfully using aluminated mesoporous silica as hard template. XRD tests and TEM observations showed that OCNT was composed of carbon nanotube arrays in p6mm symmetry. N₂ sorption analyses demonstrated that OCNT possesses typical mesoporous structure and centralized mesopore distribution. OCNT are superior to Maxsorb, an active carbon with super high surface area, in capacitive behavior and power output due to their ordered pore-structure, which favors the fast diffusion of hydrated ions. As evidenced by cyclic voltammetry measurements, OCNT show good capacitive behaviors (exhibiting a high capacitance of 180 F/g even at very high sweep rate of 50 mV/s, as compared with much reduced capacitance of 73 F/g for Maxsorb at the same sweep rate). OCNT can provide very high power density while still maintaining good energy density, thus having potential uses in electrochemical double layer capacitor (EDLC), particularly where both high power output and energy density are required.

Abstract: An amphiphilic graft copolymer with poly(acrylamide-methacrylate) as a main chain and octylphenyl polyoxyethylene as side chains (P(AM-MA)-g-C8PhEO10) was successfully synthesized via free radical copolymerization. The structure and the composition of the graft copolymer were characterized by FTIR, 1H-NMR and elemental analysis (EA) in detail. The absolute molecular weight of the copolymer is 1.304×106, as determined by static light scattering (SLS). The molar ratio of acrylamide monomer to the macromonomer is 33:1 in the copolymer and 53 C8PhEO10 branch chains attach to a P(AM-MA) backbone. The micellar behavior of P(AM-MA)-g-C8PhEO10 was preliminarily studied by means of surface tension measurements, transmission electron microscope (TEM) in aqueous solution. It was found that the stable spherical micelles with core-shell structure are formed and polymolecular micelles are larger and more compact than monomolecular micelles. In addition, the graft copolymer has favorable thermal stability.

Abstract: In this study, the nonwoven composites were made of high strength nylon 6 staples and low-melting-point polyester staples using needle-punching and thermal-bonding. By tensile strength test and constant-rate stab resistance test, the optimum parameters of the composites were obtained for developing and designing the stab-resistant nonwoven composites. The optimum experimental conditions for the nonwoven composites were as follows: the temperature for thermal-bonding was 150 °C; and the wheel speed of thermal compression was 0.5 m/min.

Abstract: This paper studies the modification of petroleum asphalt with enzymatic hydrolysis lignin (EHL) epoxy resin. EHL epoxy resin was successfully synthesized by EHL, a novel eco-material with high chemical reactivity. Different amounts of EHL epoxy resin were compounded into AH-70 paving asphalt. The effect of EHL epoxy resin on modified asphalt was examined by penetration, soften point, thin film oven test (TFOT), ductilily tests. The results showed that EHL epoxy resin had marked effect on the high-temperatrue property of increasing softening point at the content of 2-9wt% and it had significantly effect on the low-temperature properties and aging resistance with EHL epoxy resin content of 2-9wt% in modified asphalts. TG analysis indicated that EHL epoxy resin had the high mass loss temperature than pure asphalt. Anti-aging property of asphalt was improved by compounding EHL epoxy resin with asphalt.