Advanced Materials Research Vols. 912-914

Abstract: The paper briefly introduces main characteristics of chitin fibre, primary issues of wool knitted materials application in next-to-skin apparel and design of applying chitin to different wool fibre fabric. It focuses on design processes of knitted fabric, including principle of materials proportion and specification, and technique of fabric texture design. Notices regarding needles arrangement, knitting notation, and cam-setting etc. during fabric knitting, as well as production basis are also presented hereon.

Abstract: Due to the low transparency and poor gloss, the applications of ordinary opaque polypropylene are limited largely in the field of food, medicine, medical instrument and packaging. One of the ways to solve the defects mentioned above is to develop transparent polypropylene which is industrialized via polymerization and processing. The article introduces the progress of high transparent polypropylene (HTPP) all over the world.

Abstract: Gardenia yellow was applied to dye silk by mordant and direct dyeing methods. The post-mordanting dyeing exhibited the highest color depth. The effects of the categories and dosages of mordant, and the temperature, pH and time of mordanting on the color depth of the dyed silk were discussed in the post-mordanting process. Results showed that the satisfactory color depth was achieved when zinc sulfate was used as a mordant. Additionally, a low dosage of mordant, low mordanting temperature and a weakly acid medium were found to give good dyeing effects.

Abstract: In this work, the dyeing properties of three warm-dyeing reactive dyes (C.I. Reactive Orange 16, Red 198 and Blue 222) for functional viscose/chitin blend fiber containing partially deacetylated chitin were investigated. Under all the dyeing conditions, reactive dyes exhibited higher exhaustion and fixation on viscose/chitin fiber than on conventional viscose fiber. The difference of dye exhaustion and fixation between viscose/chitin and viscose fibers became greater in the following cases: low to moderate dye concentration, low dyeing temperature, no alkali, the use of the dyes with low molecular weight, etc. The dependence of the exhaustion and fixation of reactive dyes on temperature on viscose/chitin fiber was less than that on viscose fiber. The reactive dyeing of viscose/chitin fiber required only a low dosage of sodium carbonate.

Abstract: The influence of austenitization temperature on the incubation period and bainitic transformation behaviours of the high-carbon silicon steel has been investigated. It was found that the nose temperature of bainite transformation and incubation period decreases with increasing austenitization temperature. The microstructure characteristics of the bainitic transformation products have been also observed. After isothermal heat treatment at 230°C for 20 mins, all samples austenitized at different temperatures produced a bainitic structure, which consists of packets of parallel ferrite laths. The major difference lies in the edge boundary morphology. Bainitic laths formed in low-temperature austenitization conditions has sharp saw-tooth edge boundaries, whereas bainite transformed from high-temperature austenitization conditions, have smooth wedge boundaries. Key Words: austenitization temperature; low-temperature bainite; incubation period;edge boundary

Abstract: Palladium composite membranes have been prepared using an electroless plating technique with rare earth element of Ce was added into the plating solution. The effects of the rare earth element on the Pd deposition rate, plating temperature and H₂ permeation flux were studied. The experimental results show that the additions of mixed rare earth element of Ce into the plating solution can increase Pd deposition rates by 15%. The resistance to sulfidation was examined and the membrane sulfur resistance was confirmed by exposure to a combined gas of H₂ and H₂S. Keywords: hydrogen utilized; electroless plating; inorganic membrance; Cerium

Abstract: The influence of chemical composition, hardness and microstructure on resistance to abrasive wear of four kinds surfacing materials was studied. According to the results, coarse and massive carbides are not benefit for abrasion resistance, by decreasing continuity of matrix. Tiny and fine dispersed carbides combined with high toughness matrix, despite the relatively low hardness, ensure excellent abrasion resistance. Besides, material with single phase of martensite shows low hardness and low abrasion resistance.

Abstract: In order to achieve the effect of porosity on the mechanical property and acoustic emission (AE) signals of composite materials with mode I delamination, unidirectional tensile tests and real-time AE monitoring of high property and low property composites were conducted. The results show that the porosity of composite materials made a detrimental effect on the mechanical properties. As the load increases to an inflection point, the slope of the curve becomes smaller. And the slope of the high porosity specimen is lower than that of the other one. With the increase of the porosity of composite material, the failure load and tensile strength decrease. AE monitoring data show that different porosity materials lead to different evolution process of the delamination. And the corresponding AE amplitude distribution, relative energy signals are also different. Different from high porosity composites, low porosity composites generated unstable expansion at the inflection point of the load curve in the stretching process. And the highest amplitude and relative energy were obtained at the inflection point.

Abstract: Hydroxyapatite (Ca₁₀ (PO₄)₆ (OH)₂, HA) powders have been synthesized successfully by precipitation method, in which calcium hydroxide and phosphoric acid were used as precursors. The effect of reaction temperature on the HA powder formation was investigated thoroughly. The as-synthesized powders were characterized by X-ray diffraction, transmission electronic microscopy and infrared spectra spectrometer. The results show that the HA powder was prepared when the reaction temperature was 25 oC and 0 oC, but the β-tricalcium phosphate powder was synthesized at-10 oC and-20 oC. The current work suggests that the reaction temperature is the main factor which influence the synthesizing process of HA powder.

Abstract: Radiation effects on polyimide (PI) membranes were studied with different irradiation doses by ⁶⁰Co. The PI membrane were synthesized from 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (Bis-AP-AF) with 3,3',4,4'-Benzophenone tetracarboxylic dianhydride (BTDA). The single gas permeability of He, H₂, CO₂, O₂, N₂ and CH₄ were measured and compared in order to determine the effect of the the irradiation doses on the gas separation properties. The results showed that the ideal selectivity of He/CH₄, H₂/CH₄, CO₂/CH₄ and H₂/N₂ of the irradiation PI membrane can be significantly improved by irradiation of ⁶⁰Co source. The optimum irradiation doses were 50 kGy. The highest ideal selectivity of He/CH₄, H₂/CH₄, CO₂/CH₄ and H₂/N₂ is 3635.86, 2287.57, 282.00 and 205.29, respectively. In other word, the ideal selectivity of He/CH₄, H₂/CH₄, CO₂/CH₄ and H₂/N₂ of the irradiation PI membrane with 50 kGy irradiation doses is 2.27, 2.11, 1.89 and 1.08 times higher than that of the PI membranes without irradiation.