Advanced Materials Research Vols. 233-235

Abstract: Graft copolymerization of acrylamide (AM) and methyl acrylacyl oxyethyl trimethyl ammonium chloride (DMC) onto gelatin under microwave radiation was studied. The resultant ternary graft copolymer was used as wood pulp dry-strengthening agent. The application results showed that the optimum synthesis conditions was that microwave radiation power was 500W, microwave radiation time was 120S, the concentration of CAN(initiator) was 3mmol/L, m(CS): m(AM): m(DMC) =1:6:2. The breaking length and broken index of hand sheet made of wood pulp was respectively increased by 24.5% and 22.3% when the dosage of the graft copolymer was 0.8% of dry fiber weight.

Abstract: Graft copolymerization of acrylamide (AM) and diallyl dimethyl ammonium chloride (DMDAAC) onto chitosan in inverse emulsion was studied. The effect on Zeta potential and average granularity of synthetic inverse latex of the main reaction conditions such as the proportion of cationic monomer in total monomers, concentration of potassium persulfate (KPS) used as initiating agent were investigated in detail. It was shown that when the weight ratio of chitosan, AM and DMDAAC was 1:6:2, KPS concentration was 4.0mmol/L, NaHSO₃ concentration was 2.0mmol/L, stable inverse latex which had optimal performance could be gained. Good retention effect was obtained when a novel organic microparticle retention system composed of the above-mentioned chitosan-AM-DMDAAC inverse latex and anicnic polyacryamide (APAM) was applied to the deink pulp. First Pass Retention retention percentage of deink pulp was improved from 83.2% to 95.0% with the organic microparticle retention system when the dosage of inverse latex was from 0 to 0.4% of absolute dry pulp.

Abstract: The biodegradable composite films were prepared from corn stalk microcrystalline cellulose as filler and polylactic acid (PLA) as polymeric matrix. The crystallinity, the tensile properties and the thermal properties of the composites were tested. The results show that the tensile properties and thermal properties were improved with the addition of corn stalk microcrystalline cellulose. When corn stalk microcrystalline cellulose account for 10% of the PLA quality, the initial decomposition temperature was raised by 34.38, tensile strength increased by 58.3% and elongation at break increased by 31.1% compared to those of pure PLA.

Abstract: TS-1 monolithic catalysts were prepared on cordierites honeycomb ceramics supports by dip-coating method in TS-1/H₂O suspension. The cordierites honeycomb ceramics supports were treated with different methods, such as coated with a thin layer of sodium silicate, immersed in 0.5N hydrochloric acid. The monolithic catalysts were characterized by Scanning Electron Microscopy. The distribution of TS-1 Catalysts onto supported was observed. The immobilized stability of TS-1 monolithic catalysts was evaluated by ultrasonic cleaning and washing out experiment. TS-1 catalysts were uniformly deposited onto inner smoothed surface of cordierites honeycomb ceramics supports, which ware coated sodium silicate film. And experiment data proved that TS-1 catalysts may be firmly immobilized onto supports coated sodium silicate.

Abstract: Large-bulk TiB₂-TiC composite ceramics were prepared by combustion synthesis under high gravity. XRD, SEM and EDS results showed TiB₂-TiC composites were mainly composed of the fine-grained microstructures of TiC matrix in which a large number of the fine TiB₂ platelet grains were dispersed uniformly, whereas there discontinuously dispersed the ε-carbides with the enrichment of Ti atoms, and a few of isolated, irregular α-Al₂O₃ grains and Al₂O₃-ZrO₂ colonies were also observed at the boundaries of the eutectic microstructures. The results of properties indicate that with increasing mass fraction of B₄C+Ti+C in combustion systems, the relative density and fracture toughness of TiB₂-TiC composites are all among 97%~99% and 6.5~7.1 MPa·m^1/2, respectively, and the Vickers hardness and flexural strength are increased gradually to the maximum values of 28.6GPa and 615MPa, respectively. The achievement of full-density TiB₂-TiC composites benefited from the design of full-liquid SHS products and the introduction of high-gravity field, and high hardness of the composite ceramics resulted from the absence of intermediate borides and the achievement of stoichiometric TiC phases due to rapid solidification, whereas high flexural strength of the composite ceramics benefited from the homogenization and refinement of the microstructures due to the rapid separation of the liquid oxides and the rapid coupled growth of TiB₂-TiC.

Abstract: In this paper, the wear performance of a ultra-high molecular weight polyethylene composites filled with carbon fiber (CF/UHMWPE) were studied using a pin-on-disc method. The effects of surface treatment of CF and sliding load and on the friction and wear of the CF/UHMWPE composite are reported. It was observed that the sliding load is an important controlling factors; its effect is diminished when the CF is modified.

Abstract: The deterioration process of the epoxy phenolic coated tinplate in functional beverage was studied by electrochemical impedance spectroscope (EIS). The surface morphology was characterized SPM and SEM. The results showed that corrosion pits were observed on the surface after exposing the coating system to functional beverage for 364 days. The breakages of the organic coating lead to the corrosion of substrate metal. A new parameter p extracting directly from the Bode plot was presented to characterize the deterioration degree of the coating system. Using p value as the discrimination indicator of the deterioration degree of organic coating was presented in this paper.

Abstract: The article reported the reduction of methylene blue (abbreviated as MB) by ascorbic acid (abbreviated as AA) in aqueous solution. The kinetics study revealed that the reduction proceeds of MB by AA was the pseudo first order reaction. In addition, the electrochemical property of reductant AA was investigated by cyclic voltammetry (CV). The CV result indicated that the electrochemical oxide of AA was diffusion controlling at glass carbon electrode (GCE).

Abstract: Raw materials, such as SBS modified asphalt, graphite powder and crumb rubber were selected to blend with aggregate mixture to product electrically conductive asphalt concrete. Experimental results demonstrated the stress or strain had a great influence on the resistance of conductive asphalt concrete, which exhibited sensitive piezoresistivity. In fact, the piezoresistivity reflects the change in microstructure. The reason for piezoresistivity may involve proximity effect, microcrack and the dislocation of conductive paths due to shear strength of aggregates. With further study on the variation of the resistance, it is hopeful to explore the microstructure change of asphalt concrete under dynamic compressive stress. Therefore this new-style asphalt concrete has extensively practical foreground in fatigue damage testing, highway traffic intelligent monitoring and so on.

Abstract: Autoclaved characteristics of pyrite tailing are studied mixed different materials by different curing condition. The results show that compressive strength of pyrite tailing autoclaved sample is 0. Pyrite tailing autoclaved sample acquires a higher compressive strength mixed with lime. But effect of gypsum is few on compressive strength of pyrite tailing lime autoclaved system. Mixed pyrite tailing is disadvantage for compressive strength of steel slag autoclaved samples. But a higher compressive strength of steel slag pyrite tailing autoclaved sample is acquired mixed gypsum, and compressive strength of steel slag lime autoclaved sample increases mixed pyrite tailing.