Advanced Materials Research Vols. 295-297

Abstract: The chemical composition of various parts of banana stem and leaf were analysed. The soda cooking and kraft cooking process of banana stem were optimized. The bleaching performance of the banana stem pulp was discussed. The results showed that the banana stem and leaf kraft pulp were good fiber material for pulping and papermaking. The brightness of banana stem bleached pulp can reach above 80%ISO through ClO₂ bleaching.

Abstract: To prolong blast furnace campaign life, a great deal of research work has been carried out on the structure of stave cooler in the past decades, which, in turn, produced favorable results. However, due to the different thermal expanding property of the metal stave from that of the brick lining, the latter is subjected to crack, slide and damage. To solve the problem, a new stave cooler has been developed in this paper. Thus, a certain amount of anchors were welded on the traditional stave cooler, the unshaped gunning material can be fixed by anchors and the whole-lining be formed by gunning. The results of thermal simulating indicates: the bonding strength between the surface of stave cooler with anchors and the gunning lining is much higher than that between the surface of traditional stave cooler and the brick lining. Consequently, the service life of blast furnace will be extended. The optimizing design of the anchor was also described in the paper.

Abstract: Mechanical properties of Ni-Ti-Nb alloys taken by the different heat treatment processes and constraint reply conditions at low temperature had been tested respectively to analyzing the variation law. The results show that the mechanical properties of alloys under vacuum heat treatment is much better than that of alloys under cold-drawn and the general heat treatment. Additionally, there is not clear the yield plateau on the stress curve of constraint reply samples whoseσ0.2 is far greater than σs of unconstraint reply specimens, and the tensile strength is higher than the latter also.

Abstract: This work studied the effect of basic composting parameters (C/N ratio, turning frequency and moisture), initial pH, nitrogen source and fermenting agent on nitrogen loss (N-loss) during co-composting of banana stems with chicken manure in order to determine the best composting conditions. The experimental results suggested that co-compost with minimum N-loss entails operating at turning frequency with once two days, initial moisture content of 65% and C/N ratio of 25. NH₃ volatilization and N-loss were weakened under neutral conditions. Moreover, the effect of additive organic wastes and fermenting agents on N-loss during the banana stems-chicken manure co-composting was significantly different: adding bagasse or fermenting agent M-1 could effectively reduce the release of nitrogen, promotes the nitrogen accumulation, and lead to the increase of total nitrogen (TN) by 6.1 % and 6.5 %, respectively; while N-loss was enhanced with addition of paddy straw and fermenting agent M-2, with TN decreasing rate of 11.5 % and 10.9 %.

Abstract: In this paper we have investigated the substrate-induced deep level defects in bulk GaN layers grown on p-silicon by molecular beam epitaxy. Representative deep level transient spectroscopy (DLTS) performed on Au-GaN/Si/Al devices displayed only one electron trap E₁ at 0.23 eV below the conduction band. Owing to out-diffusion mechanism; silicon diffuses into GaN layer from Si substrate maintained at 1050°C, E₁ level is therefore, attributed to the silicon-related defect. This argument is supported by growth of SiC on Si substrate maintained at 1050°C in MBE chamber using fullerene as a single evaporation source.

Abstract: Aimed at the effect problem of deformation of links on position error of parallel robot, the 3-TPT parallel robot is taken as a study object. The deformation error of links of parallel robot was built by error independent principle based on kinematics; the simulation analysis also is carried out by virtual prototype technique, and the effect law of deformation of links to error of parallel robot is given. The results showed that when the deformation length of links is given, the position error can be affected by deformation of each link and the coordinate position of origin in reference frame; In the beginning of parallel robot moving, the deformation of links are small, and with the time increasing, the deformation of links obviously affect the final position error of parallel robot. The two method proposed in this paper can be used for pre-estimating the error and reducing harmful effects.

Abstract: The orthogonal method was used for analyzing the machining performance of high volume fraction SiCp/Al metal matrix composites (SiCp/Al MMCs) during high speed milling and ultrasonic high speed milling in this paper. The influence of cutting speed, feed rate and cutting depth on 3-directional forces were investigated. The results show that the cutting forces are decreased due to the cutting mechanism of SiCp/Al MMCs is changed from brittle cutting to ductile cutting during ultrasonic high speed milling. In addition, the chips exist in forms of C-type chips because of increasing rake angles. Ultrasonic high-speed milling is a more highly effective hard cutting way compared with high speed milling.

Abstract: A new series of radical-cationic UV dual curable polyurethane-modified epoxy monoacrylates (PMEMA) was prepared. Radical-cationic UV dual curable were prepared with photosensitive resin (epoxy monoacrylates (EMA) or PMEMA), reactive diluents, radical and cationic photoinitiators. UV dual cured films of those liquid compositions were obtained by using a high pressure mercury UV lamp. FTIR spectra identified the change of C=C and epoxy groups absorption peaks during the UV-curing process. The effect of different modified oligomers on the gel content, water absorption, mechanical and thermal properties of radical-cationic UV dual cured films was investigated. The characteristic C=C (1635cm^-1, 810cm^-1) and epoxide (910cm^-1, 772cm^-1) absorption speaks were no longer detectable after UV dual cured. The gel contents of all samples using PMEMA as oligomers were beyond 97.0% and their water absorption values were about 0.80%. With the length of flexible polyurethane chain segments increased, the Young’s modulus and breaking strength of UV dual cured films decreased gradually, except for the relative elongation. The volume shrinkage test indicated that the UV dual cured films exhibited lower internal stress and higher cohesive force than single radical UV cured films. The results of thermogravimetric analysis (TGA) for the UV dual cured films indicated good thermal stability with no appreciable weight loss until well above 250°C.

Abstract: The scales is a kind of precious resource with high nutritional value. The collagen protein from scales have a widely usage prospection in the areas of health food, cosmetics and so on, and they are worthy of further studied. In this paper, the method of extracting collagen protein from the scales of Tilapia was studied by pepsin hydrolysis. First, the calcium was demineralized from the scales with using of 0.5 mol/L EDTA solution, then, the scales hydrolyzed by pepsin was made to extract the collagen, and the content of L – hydroxyproline was taken as an index to measure the extraction percentage. On this basis, the collagen extract conditions was discussed from the Tilapia scales by the pepsin. It was showed that the pepsin hydrolysis conditions were the enzyme dosage 3%, citric acid 12g/L, hydrolysis time 20h, so the rate of collagen extraction is higher.

Abstract: A new automotive varying gear ratio system(VGRS)is introduced in this paper. Based on the analysis of foreign advanced theory in this field, a relationship among road wheel angle, steering wheel angle and vehicle speed is derived in order to achieve the optimum steering control for cornering and emergency maneuvers, whilst retaining the high-speed stability.