Advanced Materials Research Vol. 842

Abstract: Vitamin E (VE) was encapsulated in glassy carbohydrates by extrusion. Four typical formulations were prepared in order to have 5% and 8% VE added to each 20% and 30% modified starch containing feed material, all four formulations contained soya lecithin at 1% level as an emulsifier. The physico-chemical properties of glassy extruded products were investigated. The results showed that the VE retention rates were above 93%, meanwhile the VE oil was dispersed uniformly throughout the carbohydrate mass after extrusion. There was a slight loss for VE during the storage. The glass transition temperature (Tg) of the extrudates were above 30°C and Tg could be a good predictor of caking properties at elevated temperatures.

Abstract: This paper expounds the applications of WPC in the design of multimedia speaker box, and analyzes the advantages of WPC as the material of multimedia speaker box from three aspects: excellent acoustic performance, easily processing and environmentally friendly. It puts forth effective theoretical support for the applications of WPC in the design of multimedia speaker box.

Abstract: The galvanic and potential distributions of carbon steel immersed in seawater were studied by wire beam electrode (WBE) technique. Results indicated that the corrosion of carbon steel in seawater tended to local corrosion. With immersion time increasing, local corrosion was more and more serious. During the initial immersion period, the top of the coupon near the water surface was main cathode. With the corrosion extended, corrosion products gradually gathered on the surface of the carbon steel. Potential differences between cathode and anode gradually became small. Cathode and anode redistributed on the surface of carbon steel. At last, the top and the bottom were cathode while the middle was anode. The areas of anode first increased and then decreased. The areas of cathode were in contrast.

Abstract: To protect resource and environment, recently, the effective recycling of waste natural resources has been paid increased attention by many countries. In this study, the waste onion was used as the matrix material, and the Antheraea pernyi (A. pernyi) silk was used as the reinforcement fiber. The silk/onion composite paper with different fiber content was developed by papermaking technology. The morphological observation and tensile property tests were done. The consequence indicated that the onion had definite matrix property. Onion cell is also looked as a natural nanocomposite reinforced with cellulose microfibrils. The produced onion paper had a tensile strenght of 29.31 MPa and elongation of 1.14%. The A. pernyi silk fiber originated from waste silk quilt had the good reinforcing property for onion matrix, and the tensile property of onion-based composite with different silk fiber content was investigated. The tensile strength of this green-composite were improved remarkably to 46.2 MPa with increasing 31.75 wt% fiber content. The tensile property of this composite can be futher improved by changing the length of silk fiber and coating additives on the composite surface.

Abstract: A series of Ti-48Al-2Cr-2Nb/62%BaF2-38%CaF2 (CB) self-lubricating composites with addition of different weight percentage of solid lubricant were prepared by vacuum hot pressing sintering. Sliding wear tests against 45#steel were performed on the specimen in dry conditions, worn morphology was observed by the scanning electron microscope (SEM). The test results show that when addition of solid lubricant weight percentage is 10%, the worn surface of the composites is most smooth.The main wear mechanisms of Ti-48Al-2Cr-2Nb/62%BaF2-38%CaF2 composite are abrasive wear and adherent wear.

Abstract: During dry-wet spinning, diffusion is very important for the formation and mechanical property of fibers. In this paper, the diffusion dynamics of acetic acid (HAc) and water (H₂O) during coagulation process of cellulose acetate filament were investigated in detail. The diffusion coefficients of HAc and H₂O were calculated based on the Ficks first law of diffusion according to the experimental data. Several factors which affect the coagulation process including concentration and temperature of coagulation bath were discussed respectively. The result showed that the diffusion coefficients of HAc and H₂O increased with the increasing coagulation temperature and decreased with the increasing coagulation bath concentration.

Abstract: The semi-solid microstructure evolution of hypereutectic Al-20Si-3Fe-1Mn-4Cu-1Mg alloy was studied by unidirectional compression deformation experiment, at a range of deformation temperature of 833K~873K and a range of strain rate of 0.1s^-1~0.001s^-1. The results showed that the microstructure of the reheating alloy was more spherical and fine than the microstructure of as-cast, the alloy was a positive strain rate sensitive material that the flow stress was decreased with increasing in deformation temperature and it was increased with increasing in strain rate. The mechanical properties of the alloy were hardly improved when the deformation temperature was too high to fracture the thick phase of the alloy.The lower strain rate was not only reducing the productivity but also reducing the plastic deformation. The microstructure of the alloy which the thick phase was broken fundamentally and the grain became further refinement can be obtained at 833K~853K, and at 0.1s^-1~0.01s^-1.It can be done that reducing the plastic deformation resistance and strengthening the fabrication procedure of the alloy.

Abstract: The effect of tourmaline on growth activity of marine bacterium and the diatom Navicula perminuta was investigated by testing number of bacteria in fresh nature seawater and chlorophyll a of the diatom suspension. The concentrations of magnesium, iron and lithia tourmaline powders were controlled from 1 g/L to 15 g/L. The results showed that bacterial cells in seawater and chlorophyll a of diatom solution were reduced with increase of tourmaline powder. Tourmaline could inhibit obviously the growth activity of marine bacteria and diatom. The inhibiting effect of lithia tourmaline is strongest, that of magnesium stronger, and that of iron weakest. Whatever the tourmaline type, the higher the negative ion release rate is, the stronger is the inhibiting effect of tourmaline on growth activity of marine bacteria and diatom. Tourmaline mineral materials are expected to use as an additive to antifouling coatings from this work.

Abstract: Under the COMPASS (condensed-phase optimized molecular potentials for atomistic simulation studies) force field, the MD (molecular dynamics) simulation was applied to Polyaniline/ Graphite Composites. In this paper, we briefly introduced the constructive process of the composite system by means of MD simulation. The stability and mechanism of five intercalation composites were studied with microcosmic figure and variational energy under the invariable NVT ensemble. The results indicate that the area of graphite sheets is particularly important in the intercalation bonding process. It is the key to control the final product. The area selection is based on the molecular weight and volume of the intercalated organic polymer.

Abstract: This paper investigates imparting antibacterial properties to wood pulp cellulose via introducing quaternary phosphonium salt groups in/onto the cellulose structure to get biocidal material. The 4-carboxybutyltriphenylphosphonium bromide was grafted to cellulose in an esterification at 70°C with mechanical stirring 5h.The grafted cellulose were evaluated with FTIR and ¹H NMR. The product shows good antibacterial property against E. coli.